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Question 1
Incorrect
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What type of visual field defect are you most likely to see in a lesion of the parietal optic radiation:
Your Answer: Homonymous hemianopia with macular sparing
Correct Answer: Contralateral homonymous inferior quadrantanopia
Explanation:A lesion of the parietal optic radiation will result in a contralateral homonymous inferior quadrantanopia.
A lesion of the temporal optic radiation will result in a contralateral homonymous superior quadrantanopia. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 2
Correct
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The following statements are not true of the extensor carpi radialis brevis muscle, except?
Your Answer: It receives its blood supply from the radial artery
Explanation:Extensor carpi radialis brevis is a fusiform muscle found in the lateral part of the posterior forearm. Together with anconaeus, brachioradialis, extensor carpi radialis longus, extensor digitorum, extensor digiti minimi and extensor carpi ulnaris, it belongs to the superficial forearm extensor group. Extensor carpi radialis brevis originates from the lateral epicondyle of humerus via the common extensor tendon. This is a common origin that it shares with the extensor digitorum, extensor digiti minimi and extensor carpi ulnaris muscles. Some fibres also originate from the lateral intermuscular septum, a thick aponeurosis that covers the muscle itself, and from the radial collateral ligament.
The muscle courses inferiorly, giving off a long tendon in the middle of the forearm which descends towards the dorsal hand. The tendon passes through a groove on the posterior surface of radius, deep to the extensor retinaculum. After traversing the extensor retinaculum space, the tendon inserts into the posterior aspect of the base of the third metacarpal bone.
Extensor carpi radialis brevis is innervated directly by the radial nerve (C5- C8), or sometimes from its deep branch/posterior interosseous nerve. The radial nerve stems from the posterior cord of the brachial plexus.
The muscle is vascularized by the radial recurrent artery, radial artery and deep brachial artery (via its radial collateral branch).
Extensor carpi radialis brevis works together with extensor carpi ulnaris and extensor carpi radialis longus to extend the hand at the wrist joint. This action is vital in a sequence of muscle contractions needed for clenching a fist or making a grip. When performing these functions, wrist extension blocks the flexor muscles from on acting upon the hand. Instead, flexors act only on the digits, thereby flexing them and producing an effective hand grip, such as that seen in a tennis backhand. When the extensor carpi radialis brevis muscle contracts together with extensor carpi radialis longus and flexor carpi radialis, it contributes to producing hand abduction (radial deviation).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 3
Correct
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A 24-year-old waiter cuts his hand on a dropped plate that smashed and damages the nerve that innervates opponens digiti minimi.
The opponens digiti minimi muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: The deep branch of the ulnar nerve
Explanation:Opponens digiti minimi is a triangular-shaped muscle in the hand that forms part of the hypothenar eminence. It originates from the hook of the hamate bone and the flexor retinaculum and inserts into the medial border of the 5thmetacarpal.
Opponens digiti minimi is innervated by the deep branch of the ulnar nerve and receives its blood supply from the ulnar artery.
Opponens digiti minimi draws the fifth metacarpal bone anteriorly and rotates it, bringing the fifth digiti into opposition with the thumb. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 4
Correct
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A 32 year old man is brought to ED having been thrown off his motorbike. Following initial resuscitation and ruling out life-threatening injuries, you establish the patient has weakness of hip flexion. Which of the following nerves has most likely been injured:
Your Answer: Femoral nerve
Explanation:Flexion of the hip is produced by the iliacus, the psoas major, the sartorius, rectus femoris and the pectineus muscles. The femoral nerve innervates the iliacus, pectineus, sartorius and quadriceps femoris muscles, and supplies skin on the anterior thigh, anteromedial knee and medial leg.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 5
Correct
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A patient is sent in by her GP with suspected ectopic pregnancy. Tubal ectopic pregnancies occur most commonly in which part of the uterine tube:
Your Answer: Ampulla
Explanation:Ectopic pregnancy most commonly occurs in the ampulla (70% of cases).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 6
Correct
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A 54 year old patient presents with vertigo, ipsilateral hemiataxia, dysarthria, ptosis and miosis.
Which of these blood vessels has most likely been occluded?
Your Answer: Posterior inferior cerebellar artery
Explanation:Posterior inferior cerebellar artery (PICA) occlusion is characterised by vertigo, ipsilateral hemiataxia, dysarthria, ptosis and miosis. PICA occlusion causes infarction of the posterior inferior cerebellum, inferior cerebellar vermis and lateral medulla.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 7
Correct
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You proceed to administer lorazepam intravenously to a 21-year-old patient with status epilepticus. Which of the following best describes lorazepam's action?
Your Answer: Potentiates effect of GABA
Explanation:Lorazepam is a type of benzodiazepine.
Benzodiazepines are gamma-aminobutyric acid (GABA) receptor agonists with sedative, hypnotic, anxiolytic, anticonvulsant, and muscle relaxant characteristics that promote inhibitory synaptic transmission across the central nervous system.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 8
Correct
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A 35-year-old lady has suffered a serious brain injury. Her uvula has deviated to the right, according to inspection. Which of the following nerves is likely to be affected?
Your Answer: Left vagus nerve
Explanation:When the vagus nerve is damaged, the soft palate is paralyzed and the uvula is shifted away from the affected side. The vagus nerve innervates the uvulae muscle, which forms the uvula’s core. If only one side is innervated, contraction of the active muscle will draw the uvula towards it.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 9
Correct
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A 25-year-old man suffers from a shoulder injury that damaged the nerve that innervates the infraspinatus muscle.
Which of the following nerves may most likely be affected?Your Answer: The suprascapular nerve
Explanation:The suprascapular nerve (C5-C6) innervates the infraspinatus. It originates at the superior trunk of the brachial plexus. It runs laterally across the lateral cervical region to supply the infraspinatus and also the supraspinatus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 10
Incorrect
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After what time period should intravenous phenytoin be used as second-line treatment of status epilepticus?
Your Answer: 15 minutes
Correct Answer: 25 minutes
Explanation:If seizures recur or fail to respond after initial treatment with benzodiazepines within 25 minutes of onset, phenytoin sodium, fosphenytoin sodium, or phenobarbital sodium should be used.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 11
Correct
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A 30 year old man stabbed in the upper arm presents to the Emergency Department and you perform a vascular examination.
The brachial pulse can be best palpated at ?Your Answer: In the antecubital fossa, medial to the tendon of the biceps brachii
Explanation:The brachial artery can be palpated in the antecubital fossa, medial to the tendon of the biceps brachii muscle.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 12
Incorrect
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A 22 year old professional athlete sustains an inversion injury to her left ankle during the 800m. Which of the following ligaments is most likely injured:
Your Answer: Deltoid ligament
Correct Answer: Anterior talofibular ligament
Explanation:Inversion injuries at the ankle in plantarflexion (such as when wearing high heels) are common, and typically result in damage to the lateral collateral ligament of the ankle, made up of the anterior talofibular, the calcaneofibular and the posterior talofibular ligaments. The anterior talofibular and the calcaneofibular ligaments are most commonly injured, and the posterior talofibular ligament rarely. The spring ligament supports the head of the talus, the deltoid ligament supports the medial aspect of the ankle joint, and the long and short plantar ligaments are involved in maintaining the lateral longitudinal arch of the foot.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 13
Correct
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Which of the following nerves innervates the adductor brevis?
Your Answer: Obturator nerve
Explanation:Like the majority of the thigh adductors, adductor brevis is innervated by the obturator nerve. Obturator nerve is derived from the lumbar plexus (anterior branches of spinal nerves L2-L4).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 14
Correct
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Which of the following is NOT a typical feature of a lesion to the vestibulocochlear nerve:
Your Answer: Hyperacusis
Explanation:Hyperacusis is increased acuity of hearing with hypersensitivity to low tones resulting from paralysis of the stapedius muscle, innervated by the facial nerve. General sensation to the face and to the anterior two-thirds of the tongue is carried by the divisions of the trigeminal nerve (although taste to the anterior two-thirds of the tongue is supplied by the facial nerve). Eye movements are mediated by the oculomotor, trochlear and abducens nerve. Ptosis results from paralysis of the levator palpebrae superioris, innervated by the oculomotor nerve, or the superior tarsal muscle, innervated by the sympathetic chain.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 15
Correct
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What kind of function loss do you anticipate in a 22-year-old guy who had a laceration to his arm, resulting in nerve damage in the antecubital fossa?
Your Answer: Opposition of thumb
Explanation:The symptoms of median nerve injury include tingling or numbness in the forearm, thumb, and three adjacent fingers, as well as gripping weakness and the inability to move the thumb across the palm.
Because the thenar muscles and the flexor pollicis longus are paralyzed, flexion, abduction, and opposition of the thumb at the MCPJ and IPJ are gone.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 16
Incorrect
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A 70-year-old woman presents with right-sided loss of pain and temperature sense on the body as well as left-sided loss of pain and temperature sense on the face. She also has complaints of vertigo, nausea, and tinnitus. Further examination of her cranial nerves suggest the presence of Horner's Syndrome. An MRI and CT scan was ordered and results showed that she is suffering from a left-sided stroke.
Branches of which of the following arteries are most likely implicated in the case?Your Answer: Basilar artery
Correct Answer: Posterior inferior cerebellar artery
Explanation:Wallenberg syndrome is also known as lateral medullary syndrome and posterior inferior cerebellar artery syndrome. It is the most common posterior circulation ischemic stroke syndrome. The primary pathology of Wallenberg syndrome is occlusion of the posterior inferior cerebellar artery (PICA) or one of its branches.
It is characterized by vertigo with nystagmus, nausea and vomiting, and sometimes hiccups, dysphonia, dysarthria, and dysphagia often present with ipsilateral loss of gag reflex, ipsilateral ataxia with a tendency to fall to the ipsilateral side, pain and numbness with impaired facial sensation on the face, impaired taste sensation, and impaired pain and temperature sensation in the arms and legs.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 17
Incorrect
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Regarding antiemetics, which of the following statements is INCORRECT:
Your Answer: Cyclizine acts by inhibiting histamine pathways involved in transmission from the vestibular apparatus to the vomiting centre.
Correct Answer: Of the antiemetics, cyclizine is most commonly associated with acute dystonic reactions.
Explanation:Cyclizine acts by inhibiting histamine pathways and cholinergic pathways involved in transmission from the vestibular apparatus to the vomiting centre. Metoclopramide is a dopamine-receptor antagonist which acts both peripherally in the GI tract and centrally within the chemoreceptor trigger zone. Prochlorperazine is a dopamine-D2 receptor antagonist and acts centrally by blocking the chemoreceptor trigger zone. Metoclopramide and prochlorperazine are both commonly associated with extrapyramidal effects, such as acute dystonic reaction. Cyclizine may rarely cause extrapyramidal effects.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 18
Correct
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You are reviewing a patient following a fall from a horse. You suspect they may have an Erb's palsy as a result of a brachial plexus injury. Regarding Erb's palsy, which one of the following statements is CORRECT:
Your Answer: Erb's palsy may result in loss of sensation of the regimental badge area.
Explanation:Erb’s palsy is caused by damage to the C5 and C6 nerve roots and thus primarily involves the musculocutaneous, suprascapular and axillary nerves. It commonly result from an excessive increase in the angle between the neck and the shoulder e.g. a person thrown from a motorbike or horseback or during a difficult birth. There is loss or weakness of abduction, lateral rotation and flexion of the arm and flexion and supination of the forearm and loss of sensation on the lateral arm. A characteristic ‘Waiter’s tip’ deformity may be present where the limb hangs limply by the side, medially rotated by the unopposed action of pectoralis major with the forearm pronated due to paralysis of the biceps brachii.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 19
Correct
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A 25-year-old footballer develops pain and stiffness in his thigh. A diagnosis of iliopsoas syndrome is made.
Iliacus is innervated by which of the following nerves? Select ONE answer only.Your Answer: Femoral nerve
Explanation:Iliacus is innervated by the femoral nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 20
Correct
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Regarding the abductor pollicis longus, which of the following statements is true?
Your Answer: It extends the thumb at the carpometacarpal joint
Explanation:Abductor pollicis longus is a muscle found in the posterior compartment of the forearm. It is one of the five deep extensors in the forearm, along with the supinator, extensor pollicis brevis, extensor pollicis longus and extensor indicis.
Abductor pollicis longus is innervated by the posterior interosseous nerve (C7, C8), which is a continuation of the deep branch of the radial nerve. The radial nerve is a branch of the posterior cord of the brachial plexus.
Blood supply to the abductor pollicis longus muscle comes from the interosseous branches of the ulnar artery.
Acting alone or with abductor pollicis brevis, abductor pollicis longus pulls the thumb away from the palm. More specifically, it produces (mid-) extension and abduction of the thumb at the first metacarpophalangeal joint. This action is seen in activities such as bowling and shovelling.
Working together with the long and short extensors of the thumb, the muscle also helps to fully extend the thumb at the metacarpophalangeal joint. This action is important for loosening the hand grip, for example, when letting go of objects previously being held. Abductor pollicis longus also helps to abduct the hand (radial deviation) at the radiocarpal joint.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 21
Correct
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Which of the following statements concerning the facial nerve is INCORRECT?
Your Answer: Forehead sparing in facial nerve palsy is indicative of a lower motor neuron lesion.
Explanation:In facial nerve palsy, LMN damage will involve the forehead and there will be an inability to close the eyes due to paralysis of the orbicularis oculi or raise the eyebrows due to paralysis of the occipitofrontalis muscle.
UMN damage causes sparing of the forehead as the occipitofrontalis and orbicularis oculi muscles have bilateral cortical representation. -
This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 22
Incorrect
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Elevation of the mandible is produced primarily by which of the following muscles:
Your Answer: Temporalis, geniohyoid and mylohyoid
Correct Answer: Temporalis, masseter and medial pterygoid
Explanation:Elevation of the mandible is generated by the temporalis, masseter and medial pterygoid muscles.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 23
Incorrect
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Which of the following is true regarding respiration?
Your Answer: The ‘bucket handle’ action of the ribs is their downward and lateral movement
Correct Answer: The diaphragm is responsible for abdominal breathing
Explanation:The following are the mechanisms of breathing during inspiration and expiration, whether normal or forced.
Normal inspiration is an active process, with the diaphragm as the main muscle. The diaphragm descends, ribs move upward and outward, and the lungs become wider and taller.
In forced inspiration, which commonly occurs during exercise, the external intercostals and accessory muscles, such as the sternocleidomastoid, anterior serrati, scalenes, alae nasi, genioglossus and arytenoid are involved. The ribs move upward and outward, and the abdominal contents move downward.
Normal expiration is a passive process, while in forced expiration, the internal intercostals and abdominal muscles, such as the rectus abdominis, internal and external obliques and transversus abdominis are involved. The ribs move downward and inward, and the abdominal contents move upward.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 24
Incorrect
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A 20-year-old patient had sustained a supracondylar fracture due to falling from a skateboard. The frequency of acute nerve injuries accompanying supracondylar humeral fractures ranges from 10 to 20%. The most common complication is injury to which nerve?
Your Answer: Radial nerve
Correct Answer: Median nerve
Explanation:According to various studies, the frequency of acute nerve damage associated with supracondylar humeral fractures in children ranges from 10% to 20%.
Median nerve injury and anterior interosseous nerve injury are the most common consequences.
Damage to this nerve indicated weakening or abnormal extension of the index finger’s distal interphalangeal joint and the thumb’s interphalangeal joint. The absence of sensibility is a distinguishing attribute.
A surgical neck humerus fracture may cause injury to the axillary nerve. A midshaft humerus fracture might cause injury to the radial nerve. A medial epicondylar fracture might cause injury to the ulnar nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 25
Incorrect
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A 27-year-old man has been diagnosed with testicular cancer and has spread to the regional lymph nodes.
The lymph from the testes will drain to which of the following nodes?Your Answer: Deep inguinal lymph nodes
Correct Answer: Para-aortic lymph nodes
Explanation:Testes are retroperitoneal organs and its lymphatic drainage is to the lumbar and para-aortic nodes along the lumbar vertebrae.
The scrotum is the one which drains into the nearby superficial inguinal nodes.
The glans penis and clitoris drains into the deep inguinal lymph nodes.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 26
Correct
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A patient suffers an injury to the nerve that innervates gluteus medius.
The gluteus medius muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: Superior gluteal nerve
Explanation:Gluteus minimus is innervated by the superior gluteal nerve.
Gluteus medius is innervated by the superior gluteal nerve.
Gluteus maximus is innervated by the inferior gluteal nerve. -
This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 27
Correct
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A 18 year old student presents to ED with a headache, fever and photophobia. You suspect meningitis and agree to observe your junior performing a lumbar puncture. What is the highest safest vertebral level to perform lumbar puncture in adults:
Your Answer: L3/L4
Explanation:In adults, the spinal cord typically ends between L1/L2 whereas the subarachnoid space extends to approximately the lower border of vertebra S2. Lumbar puncture is performed in the intervertebral space L4/L5 or L3/L4.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 28
Incorrect
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A 35-year-old man suffers an open fracture of his forearm. The nerve that innervates the pronator quadratus muscle is damaged as a consequence of this injury.
Which of the following nerves has been damaged in this case? Select ONE answer only.Your Answer: The median nerve
Correct Answer: The anterior interosseous nerve
Explanation:Pronator quadratus is a small, square-shaped muscle that lies in the anterior compartment of the forearm. It arises from the distal fourth of the anterior surface of the ulna and inserts into the distal fourth of the anterior surface of the radius.
Pronator quadratus is innervated by the anterior interosseous nerve. It receives its blood supply from the anterior interosseous artery, which is a branch of the common interosseous artery, which in turn is a branch of the ulnar artery.
The main action of pronator quadratus is to assist pronator teres with pronation of the forearm. The deep fibres bind the radius and ulna together.
The pronator quadratus muscle highlighted in blue (adapted from Gray’s Anatomy) -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 29
Correct
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Which of the following is a well recognised adverse effect of prochlorperazine:
Your Answer: Acute dystonic reaction
Explanation:Adverse actions include anticholinergic effects such as drowsiness, dry mouth, and blurred vision, extrapyramidal effects, and postural hypotension. Phenothiazines can all induce acute dystonic reactions such as facial and skeletal muscle spasms and oculogyric crises; children (especially girls, young women, and those under 10 kg) are particularly susceptible.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 30
Correct
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Where on the body is the radial artery pulsation best palpated?
Your Answer: At the wrist just lateral to the flexor carpi radialis tendon
Explanation:The radial artery lies lateral to the large tendon of the flexor carpi radialis muscle and anterior to the pronator quadratus at the distal end of the radius. The flexor carpi radialis muscle is used as a landmark in locating the pulse.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 31
Incorrect
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A 60-year-old man with trauma to his cervical spine suffers from damage to the ansa cervicalis, resulting to paresis of his infrahyoid muscles.
All of the following are considered infrahyoid muscles, except:Your Answer: Sternothyroid
Correct Answer: Mylohyoid
Explanation:Infrahyoid muscles are also known as “strap muscles” which connect the hyoid, sternum, clavicle and scapula. They are located below the hyoid bone on the anterolateral surface of the thyroid gland and are involved in movements of the hyoid bone and thyroid cartilage during vocalization, swallowing and mastication. They are composed of four paired muscles, organized into two layers.
Superficial layer consists of the sternohyoid and omohyoid
Deep layer consists of the sternothyroid and thyrohyoid. -
This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 32
Correct
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During quiet respiration, position of the right oblique fissure can be marked by a line drawn on the thoracic wall that:
Your Answer: Begins at the spinous process of T4, crosses the fifth intercostal space laterally and follows the contour of rib 6 anteriorly.
Explanation:During quiet respiration, the approximate position of the right oblique fissure can be marked by a line on the thoracic wall that begins at the spinous process of vertebra T4, crosses the fifth intercostal space laterally and then follows the contour of rib 6 anteriorly.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 33
Correct
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All of the muscles of the tongue (other than the palatoglossus) are innervated by which of the following nerves:
Your Answer: Hypoglossal nerve
Explanation:All of the muscles of the tongue are innervated by the hypoglossal nerve, except for the palatoglossus, which is innervated by the vagus nerve.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 34
Correct
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Aside from the inability to extend the leg above the knee, which of the following clinical symptoms should you anticipate seeing in a patient who had a pelvic and right leg injury as well as femoral nerve damage?
Your Answer: Loss of sensation over the anterior thigh
Explanation:The femoral nerve runs down the front of the leg from the pelvis. It gives the front of the thigh and a portion of the lower leg sensation.
Extension of the leg at the knee joint, flexion of the thigh at the hip are produced by muscles that is primarily innervated by the femoral nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 35
Correct
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Superficial fibular nerve palsy results in which of the following clinical features:
Your Answer: Loss of eversion of the foot
Explanation:Damage to the superficial fibular nerve results in loss of eversion of the foot and loss of sensation over the lower anterolateral leg and the dorsum of the foot.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 36
Correct
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You are examining the lower limbs of a 54 year old man who presented after falling from a ladder at home. During your neurological assessment you note a weakness of hip flexion. Which of the following nerves is the most important for flexion of the thigh at the hip joint:
Your Answer: Femoral nerve
Explanation:Flexion of the thigh at the hip joint is produced by the sartorius, psoas major, iliacus and pectineus muscles, assisted by the rectus femoris muscle, all innervated by the femoral nerve (except for the psoas major, innervated by the anterior rami of L1 – 3).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 37
Correct
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What is the main mechanism of action of metoclopramide:
Your Answer: Dopamine antagonist
Explanation:Metoclopramide is a dopamine-receptor antagonist. Blockade of inhibitory dopamine receptors in the GI tract may allow stimulatory actions of ACh at muscarinic synapses to predominate. Metoclopramide also blocks dopamine D2-receptors within the chemoreceptor trigger zone (CTZ). At high doses, it is also thought to have some 5-HT3antagonist activity.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 38
Correct
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Carbamazepine is indicated for all of the following EXCEPT for:
Your Answer: Myoclonic seizures
Explanation:Carbamazepine is a drug of choice for simple and complex focal seizures and is a first-line treatment option for generalised tonic-clonic seizures. It is also used in trigeminal neuralgia and diabetic neuropathy. Carbamazepine may exacerbate tonic, atonic, myoclonic and absence seizures and is therefore not recommended if these seizures are present.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 39
Correct
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A 30-year-old man suffers from an open femoral shaft fracture after being involved in a road traffic accident. As a consequence of his injury, the nerve that was damaged innervates the popliteus muscle.
In which of the following nerves is the popliteus muscle innervated by?Your Answer: Tibial nerve
Explanation:The popliteus muscle is innervated by the tibial nerve (L4, 5 and S1).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 40
Correct
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Contraction of the diaphragm results in which of the following effects:
Your Answer: Increased vertical dimension of the thorax
Explanation:Contraction of the diaphragm (as in inspiration) results in flattening (depression) of the diaphragm with an increase in vertical dimension of the thorax. This results in decreased intrathoracic pressure and increased intra-abdominal pressure.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 41
Correct
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Elevation of the eyeball is primarily produced by which of the following muscles:
Your Answer: Superior rectus and inferior oblique
Explanation:Elevation of the eyeball is produced by the superior rectus and the inferior oblique muscles.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 42
Correct
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Which anatomical structure is divided following an emergency department anterolateral thoracotomy?
Your Answer: Latissimus dorsi
Explanation:Thoracotomy describes an incision made in the chest wall to access the contents of the thoracic cavity. Thoracotomies typically can be divided into two categories; anterolateral thoracotomies and posterolateral thoracotomies. These can be further subdivided into supra-mammary and infra-mammary and, of course, further divided into the right or left chest. Each type of incision has its utility given certain circumstances.
A scalpel is used to sharply divide the skin along the inframammary crease overlying the fifth rib. Electrocautery is then used to divide the pectoralis major muscle and serratus anterior muscle. Visualization of the proper operative field can be achieved with the division and retraction of the latissimus dorsi. Either the fourth or fifth intercostal space is then entered after the division of intercostal muscles above the rib to ensure the preservation of the neurovascular bundle. Once the patient is properly secured to the operating table, the ipsilateral arm is raised and positioned anteriorly and cephalad to rest above the head. The incision is started along the inframammary crease and extended posterolaterally below the tip of the scapula. It is then extended superiorly between the spine and the edge of the scapula, a short distance. The trapezius muscle and the subcutaneous tissues are divided with electrocautery. The serratus anterior and latissimus dorsi muscles are identified and can be retracted. The intercostal muscles are then divided along the superior border of the ribs, and the thoracic cavity is accessed.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 43
Incorrect
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An X-ray of a 24-year-old female hockey player who arrives at the hospital with a left foot injury reveals an avulsion fracture of the fifth metatarsal tuberosity. Which of the following muscles is most likely responsible for the movement of the fractured fragment?
Your Answer: Fibularis longus
Correct Answer: Fibularis brevis
Explanation:An avulsion fracture of the base of the fifth metatarsal happens when the ankle is twisted inwards.
When the ankle is twisted inwards a muscle called the fibularis brevis contracts to stop the movement and protect the ligaments of the ankle.
The base of the fifth metatarsal is where this muscle is attached. The group of lateral leg muscles that function to plantarflex the foot includes the fibularis brevis and the fibularis longus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 44
Correct
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Regarding the flexor digitorum profundus muscle, which of the following is true?
Your Answer: The medial aspect of the muscle is innervated by the ulnar nerve
Explanation:Flexor digitorum profundus is a fusiform muscle located deep within the anterior (flexor) compartment of the forearm. Along with the flexor pollicis longus and pronator quadratus muscles, it comprises the deep flexor compartment of the forearm.
Flexor digitorum profundus has a dual innervation:
(1) The medial part of the muscle, that inserts to the fourth and fifth digits, is innervated by the ulnar nerve (C8-T1);
(2) The lateral part, that inserts to the second and third digits, is innervated by the median nerve, via anterior interosseous branch (C8-T1).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 45
Incorrect
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A patient presents with a laceration on his hand and wrist that has cut the nerve that innervates opponens pollicis.
The opponens pollicis muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer: The anterior interosseous nerve
Correct Answer: The recurrent branch of the median nerve
Explanation:Opponens pollicis is a small, triangular muscle that forms part of the thenar eminence. It originates from the flexor retinaculum and the tubercle of trapezium bone and inserts into the whole length of the first metacarpal bone on its radial side.
Opponens pollicis is innervated by the recurrent branch of the median nerve and receives its blood supply from the superficial palmar arch.
The main action of opponens pollicis is to flex the first metacarpal bone at the carpometacarpal joint, which opposes the thumb towards the centre of the palm. It also medially rotates the first metacarpal bone at the carpometacarpal joint. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 46
Correct
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Regarding the tongue, which of the following statements is CORRECT:
Your Answer: The lymphatic supply of the tongue drains to the jugulo-omohyoid node of the deep cervical chain.
Explanation:All lymphatics from the tongue ultimately drain into the deep cervical chain of nodes along the internal jugular vein, particularly the jugulo-omohyoid lymph node.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 47
Correct
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An injury to the brachial plexus can cause Erb's palsy. The following is expected to happen to a patient suffering from this condition, except for which one:
Your Answer: Weakness of medial rotation of the arm
Explanation:Erb’s palsy can be caused by a traumatic force downward on the upper arm and shoulder that damages the upper root of the brachial plexus.
The patient will lose shoulder abduction (deltoid, supraspinatus), shoulder external rotation (infraspinatus), and elbow flexion as a result of this condition (biceps, brachialis).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 48
Correct
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Which of the following statement is correct with regards to the female urethra?
Your Answer: The urethra opens in the vestibule that lies between the labia minora.
Explanation:The urethra in women is short (about 4 cm long), and begins at the base of the bladder. Its course runs inferiorly through the urogenital diaphragm, then into the perineum. It then opens in the vestibule which lies between the labia minora. The inferior aspect of the urethra is bound to the anterior surface of the vagina. The urethral opening is anterior to the vaginal opening in the vestibule. As the urethra passes through the pelvic floor, it is surrounded by the external urethral sphincter.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 49
Incorrect
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A 77 year old lady presents to ED with her left leg shortened and externally rotated following slipping and falling on a wet bathroom floor. There is an intracapsular fracture of the neck of femur seen on imaging studies. She is at risk of avascular necrosis of the head of femur.
This is caused by lack of blood supply from which of these arteries?
Your Answer: Lateral circumflex artery
Correct Answer: Medial circumflex artery
Explanation:The primary blood supply to the head of the femur is from branches of the medial femoral circumflex artery.
The superior and inferior gluteal arteries supply the hip joint but not the head of femur.
The lateral circumflex artery anastomoses with the medial femoral circumflex artery and assists in supplying the head of femur.
The obturator artery is an important source of blood supply in children up to about 8 years. It gives rise to the artery of the head of femur which runs in the ligamentum teres and is insufficient to supply the head of femur in adults.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 50
Incorrect
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A 25 year old man presents to the emergency room with abdominal pain, vomiting and constipation. A CT scan is done which is suggestive of Meckel's diverticulum. Where does the blood supply of the Meckel's diverticulum originate?
Your Answer: Inferior mesenteric artery
Correct Answer: Superior mesenteric artery
Explanation:Meckel’s diverticulum has certain classic characteristics.
1. It lies on the antimesenteric border of the middle-to-distal ileum
2. It is approximately 2 feet proximal to the ileocaecal junction
3. It appears as a blind-ended tubular outpouching of bowel
4. It is about 2 inches long,
5. It occurs in about 2% of the population,
6. It may contain two types of ectopic tissue (gastric and pancreatic).
7. The diverticulum is supplied by the superior mesenteric artery.
8. Proximal to the major duodenal papilla the duodenum is supplied by the gastroduodenal artery (branch of the coeliac trunk)
9. Distal to the major duodenal papilla it is supplied by the inferior pancreaticoduodenal artery (branch of superior mesenteric artery).
10. The arterial supply to the jejunoileum is from the superior mesenteric artery. -
This question is part of the following fields:
- Abdomen
- Anatomy
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Question 51
Incorrect
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Which of the following muscles inserts into the patella?
Your Answer: The hamstring muscles
Correct Answer: The quadriceps femoris complex
Explanation:The quadriceps femoris muscle translates to “four-headed muscle” from Latin. It bears this name because it consists of four individual muscles; rectus femoris, vastus medialis, vastus lateralis, and vastus intermedius. Out of all four muscles, only the rectus femoris crosses both the hip and knee joints. The others cross only the knee joint. These muscles differ in their origin, but share a common quadriceps femoris tendon which inserts into the patella. The function of the quadriceps femoris muscle is to extend the leg at the knee joint and to flex the thigh at the hip joint.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 52
Correct
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A 70-year old male is taken to the Emergency Room after suffering a traumatic fall while showering. Upon physical examination, the attending physician noted a hyperextended neck, 1/5 muscle strength in both upper extremities, 4/5 muscle strength in both lower extremities, and variable loss in sensation. The patient is placed in the wards for monitoring. For the next 24 hours, anuria is noted.
Which of the following spinal cord injuries is the most likely diagnosis?Your Answer: Central cord syndrome
Explanation:Central cord syndrome is the most common type of incomplete cord injury and almost always occurs due to a traumatic injury. It results in motor deficits that are worse in the upper extremities as compared to the lower extremities. It may also cause bladder dysfunction (retention) and variable sensory deficits below the level of injury.
The majority of these patients will be older and present with symptoms after a fall with hyperextension of their neck. On examination, patients will have more significant strength impairments in the upper extremities (especially the hands) compared to the lower extremities. Patients often complain of sensory deficits below the level of injury, but this is variable. Pain and temperature sensations are typically affected, but the sensation of light touch can also be impaired. The most common sensory deficits are in a cape-like distribution across their upper back and down their posterior upper extremities. They will often have neck pain at the site of spinal cord impingement.
Bladder dysfunction (most commonly urinary retention) and priapism can also be signs of upper motor neuron dysfunction. The sacral sensation is usually preserved, but the clinician should assess the rectal tone to evaluate the severity of the compression.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 53
Correct
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A patient suffers a stab wound to the neck. The entry point of the blade is situated within the posterior triangle of the neck.
Which of the following muscles is most likely to be involved? Select ONE answer only.Your Answer: Anterior scalene
Explanation:The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:
Muscles: thyrohyoid, sternothyroid, sternohyoid muscles
Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland
Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries
Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins
Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerveThe posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.
Contents:
Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes
Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus
Of the muscles listed in the options, only the anterior scalene is situated within the posterior triangle of the neck. -
This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 54
Correct
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The muscles of the soft palate (other than the tensor veli palatini) are innervated by which of the following nerves:
Your Answer: Vagus nerve
Explanation:All of the muscles of the soft palate are innervated by the vagus nerve (from the pharyngeal plexus), except for the tensor veli palatini, which is innervated by a branch of the mandibular nerve.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 55
Correct
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The sensory innervation of the oropharynx is provided by which of the following nerves:
Your Answer: Glossopharyngeal nerve
Explanation:Each subdivision of the pharynx has a different sensory innervation:the nasopharynx is innervated by the maxillary nervethe oropharynx is innervated by the glossopharyngeal nervethe laryngopharynx is innervated by the vagus nerve.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 56
Incorrect
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Which of the following statements is true regarding the extensor pollicis longus?
Your Answer: Its tendons form the lateral border of the anatomical snuffbox
Correct Answer: It is innervated by the posterior interosseous nerve
Explanation:Extensor pollicis longus is part of the deep extensors of the forearm together with extensor pollicis brevis, abductor pollicis longus, extensor indicis and supinator muscles. It is located on the posterior aspect of forearm, extending from the middle third of the ulna, and adjacent interosseous membrane, to the distal phalanx of the thumb.
Extensor digitorum is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).
Extensor pollicis brevis receives its blood supply from the posterior interosseous artery and perforating branches of the anterior interosseous artery.
The main action of extensor pollicis longus is extension of the thumb at the metacarpophalangeal and interphalangeal joints. Extension at the metacarpophalangeal joint occurs in synergy with extensor pollicis brevis muscle. When the thumb reaches the full extension or abduction, extensor pollicis longus can also assist in adduction of the thumb.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 57
Correct
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A lesion to which part of the optic radiation will result in contralateral homonymous inferior quadrantanopia?
Your Answer: Right parietal lobe
Explanation:A visual loss in the lower left quadrant in both visual fields is an indication of an inferior homonymous. This is due to a lesion of the superior fibres of the optic radiation in the parietal lobe on the contralateral side of the visual pathway.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 58
Incorrect
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A 36-year-old man who works in a farm presents with a deep laceration over the palm of his hand. A median nerve block was performed at his wrist to facilitate wound exploration and closure.
Which of the following statements regarding median nerve blocks at the wrist is considered correct?Your Answer: Palmaris longus can always be used to locate the median nerve
Correct Answer: The needle should be inserted approximately 2.5 cm proximal to flexor retinaculum
Explanation:A median nerve block is a simple, safe, and effective method of obtaining anaesthesia to the palmar aspect of the thumb, index finger, middle finger, radial portion of the palm and ring finger. The median nerve lies deep to the flexor retinaculum and about one centimetre under the skin of the volar wrist.
The palmaris longus tendon lies superficial to the retinaculum and is absent in up to 20% of patients.
The median nerve is located slightly lateral (radial) to the palmaris longus tendon and medial (ulnar) to the flexor carpi radialis tendon.The procedure is as follows:
– Check sensation and motor function of the median nerve. Wear gloves and use appropriate barrier precautions.
– Locate the flexor carpi radialis and palmaris longus tendons, which become prominent when the patient flexes the wrist against resistance. The palmaris longus tendon is usually the more prominent of the two tendons.
– Needle-entry site: The needle will be inserted adjacent to the radial (lateral) border of the palmaris longus tendon just proximal to the proximal wrist crease. If the palmaris longus tendon is absent, the needle-entry site is about 1 cm ulnar to the flexor carpi radialis tendon.
– Cleanse the site with antiseptic solution. Place a skin wheal of anaesthetic, if one is being used, at the needle-entry site.
– Insert the needle perpendicularly through the skin and advance it slowly until a slight pop is felt as the needle penetrates the flexor retinaculum. When paraesthesia in the distribution of the median nerve confirms proper needle placement, withdraw the needle 1 to 2 mm.
– Aspirate to exclude intravascular placement and then slowly (i.e., over 30 to 60 seconds) inject about 3 mL of anaesthetic. If the patient does not feel paraesthesia, redirect the needle in an ulnar direction, under the palmaris longus tendon. If paraesthesia is still not felt, slowly inject 3 to 5 mL of anaesthetic in the proximity of the nerve 1 cm deep to the tendon.
– Allow about 5 to 10 minutes for the anaesthetic to take effect. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 59
Correct
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Compression of this nerve can cause weakness in the left leg while walking and thigh adduction weakness at the hip joint.
Your Answer: Obturator nerve
Explanation:The obturator nerve is a sensory and motor nerve that emerges from the lumbar plexus and innervates the thigh.
This nerve supplies motor innervation to the medial compartment of the thigh, making it necessary for thigh adduction.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 60
Incorrect
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A foot drop is a sign of damage to which of the following nerves?
Your Answer: Tibial nerve
Correct Answer: Deep fibular nerve
Explanation:The deep fibular nerve was previously referred to as the anterior tibial nerve.
It starts at the common fibular nerve bifurcation, between the fibula and the proximal part of the fibularis longus. Damage to this nerve can cause foot drop or loss of dorsiflexion since this nerve controls the anterior leg muscles.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 61
Incorrect
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Which of the following ligaments supports the head of the talus?
Your Answer: Long plantar ligament
Correct Answer: Spring ligament
Explanation:The spring-ligament complex is a significant medial arch stabilizer.
The two important functions of this ligament include promoting the stability of the talonavicular joint by acting as a support for the talus head and by acting as a static support to maintain the medial longitudinal arch.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 62
Incorrect
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All of the following typically occurs as part of normal inspiration except:
Your Answer: Upwards and forward movements of the sternum
Correct Answer: Contraction of the internal intercostal muscles
Explanation:Passive inspiration is a result of contraction of the diaphragm (depressing the diaphragm) and the external intercostal muscles (elevating the ribs).
In inspiration, several movements occur. These are:
1. elevation of the sternal ends of the ribs (‘pump handle’ movement),
2. elevation of the lateral shafts of the ribs (‘bucket handle’ movement)
3. depression of the diaphragm.
These result in expansion of the thorax in an anteroposterior, transverse and vertical direction respectively. There is an increased intrathoracic volume and decreased intrathoracic pressure and air is drawn into the lungs. -
This question is part of the following fields:
- Anatomy
- Thorax
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Question 63
Incorrect
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The most common complication of paracetamol overdose is:
Your Answer: Arrhythmias
Correct Answer: Hepatic failure
Explanation:The maximum daily dose of paracetamol in an adult is 4 grams. Doses greater than this can lead to hepatotoxicity and, less frequently, acute kidney injury. Early symptoms of paracetamol toxicity include nausea, vomiting, and abdominal pain, and usually settle within 24 hours. Symptoms of liver damage include right subcostal pain and tenderness, and this peaks 3 to 4 days after paracetamol ingestion. Other signs of hepatic toxicity include encephalopathy, bleeding, hypoglycaemia, and cerebral oedema.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 64
Incorrect
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After a work-related accident, a 33-year old male is taken to the emergency room with difficulty in adduction and flexion of his left arm at the glenohumeral joint. The attending physician is suspects involvement of the coracobrachialis muscle.
The nerve injured in the case above is?Your Answer: The dorsal scapular nerve
Correct Answer: The musculocutaneous nerve
Explanation:The coracobrachialis muscle is innervated by the musculocutaneous nerve (C5-C7) a branch of the lateral cord of the brachial plexus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 65
Incorrect
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In a patient with an ongoing seizure, after what time period should treatment be commenced?
Your Answer: 10 minutes
Correct Answer: 5 minutes
Explanation:Immediate emergency care and treatment should be given to children, young people and adults who have prolonged or repeated convulsive seizures.
Prolonged seizures last 5 minutes or more.
Repeated seizures refer to 3 or more seizures in an hour. -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 66
Incorrect
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A patient complains of headache and visual loss. CT scan demonstrates a lesion of the temporal lobe. What type of visual field defect would you most expect to see in this patient:
Your Answer: Homonymous hemianopia with macular sparing
Correct Answer: Contralateral homonymous superior quadrantanopia
Explanation:Axons from the lateral geniculate nucleus (LGN) carry visual information, via the upper and lower optic radiations, to the visual cortex in the occipital lobe:
The upper optic radiation carries fibres from the superior retinal quadrants (corresponding to the inferior visual field quadrants) and travels through the parietal lobe to reach the visual cortex.
The lower optic radiation carries fibres from the inferior retinal quadrants (corresponding to the superior visual field quadrants) and travels through the temporal lobe to reach the visual cortex of the occipital lobe. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 67
Incorrect
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If a lesion is observed in Broca's area, which function is expected to become affected?
Your Answer: Recognition and integration of visual stimuli
Correct Answer: Formation of words
Explanation:The primary functions of the Broca area are both language production and comprehension. While the exact role in the production is still unclear, many believe that it directly impacts the motor movements to allow for speech. Although originally thought to only aid in speech production, lesions in the area can rarely be related to impairments in the comprehension of language. Different regions of the Broca area specialize in various aspects of comprehension. The anterior portion helps with semantics, or word meaning, while the posterior is associated with phonology, or how words sound. The Broca area is also necessary for language repetition, gesture production, sentence grammar and fluidity, and the interpretation of others’ actions.
Broca’s aphasia is a non-fluent aphasia in which the output of spontaneous speech is markedly diminished and there is a loss of normal grammatical structure. Specifically, small linking words, conjunctions, such as and, or, and but, and the use of prepositions are lost. Patients may exhibit interjectional speech where there is a long latency, and the words that are expressed are produced as if under pressure. The ability to repeat phrases is also impaired in patients with Broca’s aphasia. Despite these impairments, the words that are produced are often intelligible and contextually correct. In pure Broca’s aphasia, comprehension is intact.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 68
Incorrect
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At rest, the left dome of the diaphragm normally reaches as high as which of the following:
Your Answer: Sixth intercostal space
Correct Answer: Fifth intercostal space
Explanation:At rest the right dome of the diaphragm lies slightly higher than the left; this is thought to be due to the position of the liver. In normal expiration, the normal upper limits of the superior margins are the fifth rib for the right dome, the fifth intercostal space for the left dome and the xiphoid process for the central tendon.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 69
Incorrect
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A 23-year-old student presents with a fever and sore throat. Upon physical examination, it was observed that he had bilaterally enlarged tonsils that are covered in large amounts of exudate. A diagnosis of tonsillitis was made.
The lymph from the tonsils will drain to which of the following nodes?Your Answer: Superficial cervical lymph nodes
Correct Answer: Deep cervical lymph nodes
Explanation:The tonsils are collections of lymphatic tissue located within the pharynx. They collectively form a ringed arrangement, known as Waldeyer’s ring: pharyngeal tonsil, 2 tubal tonsils, 2 palatine tonsils, and the lingual tonsil.
Lymphatic fluid from the lingual tonsil drains into the jugulodigastric and deep cervical lymph nodes.
Lymphatic fluid from the pharyngeal tonsil drains into the retropharyngeal nodes (which empty into the deep cervical chain), and directly into deep cervical nodes within the parapharyngeal space.
The retropharyngeal and the deep cervical lymph nodes drain the tubal tonsils.
The palatine tonsils drain to the jugulodigastric node, a node of the deep cervical lymph nodes, located inferior to the angle of the mandible.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 70
Incorrect
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A patient is referred to the Medicine Department for complaints of unilateral hearing loss, tinnitus and facial numbness. Upon further investigation, an acoustic neuroma is given as the final diagnosis.
Which of the following nerves is least likely to be affected in acoustic neuroma?Your Answer: Vestibulocochlear nerve
Correct Answer: Trochlear nerve
Explanation:Acoustic neuroma is also called vestibular schwannoma (VS), acoustic neuroma, vestibular neuroma or acoustic neurofibroma. These are tumours that evolve from the Schwann cell sheath and can be either intracranial or extra-axial. They usually occur adjacent to the cochlear and vestibular nerves and most often arise from the inferior division of the latter. Anatomically, acoustic neuroma tends to occupy the cerebellopontine angle. About 5-10% of cerebellopontine angle (CPA) tumours are meningiomas and may occur elsewhere in the brain. Bilateral acoustic neuromas tend to be exclusively found in individuals with type 2 neurofibromatosis.
The following nerves may be affected due to nerve compression:
Facial nerve: usually minimal with late presentation except for very large tumours. Depending on the degree of engagement of the nerve, the symptoms may include twitching, increased lacrimation and facial weakness.
Trigeminal Nerve: paraesthesia in the trigeminal distribution, tingling of the tongue, impairment of the corneal reflex, and less commonly pain which may mimic typical trigeminal neuralgia.
Glossopharyngeal and Vagus nerves: palatal paresis, hoarseness of voice and dysphagia
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 71
Incorrect
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A patient presents with an adducted eye at rest which cannot abduct past the midline, which of the following cranial nerves is most likely to be affected:
Your Answer: Oculomotor nerve
Correct Answer: Abducens nerve
Explanation:Abducens nerve palsies result in a convergent squint at rest (eye turned inwards) with inability to abduct the eye because of unopposed action of the rectus medialis. The patient complains of horizontal diplopia when looking towards the affected side. With complete paralysis, the eye cannot abduct past the midline.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 72
Incorrect
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Following a road traffic collision, a patient sustains damage to the long thoracic nerve. Which of the following clinical findings would you most expect to see on examination:
Your Answer: Complete loss of abduction of the arm
Correct Answer: Winged scapula deformity
Explanation:Damage to the long thoracic nerve results in weakness/paralysis of the serratus anterior muscle. Loss of function of this muscle causes the medial border, and particularly the inferior angle, of the scapula to elevate away from the thoracic wall, resulting in the characteristic ‘winging’ of the scapula. This deformity becomes more pronounced if the patient presses the upper limb against a wall. Furthermore, normal elevation of the arm is no longer possible.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 73
Incorrect
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Needle thoracentesis in a patient with a tension pneumothorax is performed at which anatomical landmark?
Your Answer: 3rd intercostal space mid-clavicular line
Correct Answer: 4th or 5th intercostal space mid-axillary line
Explanation:Tension pneumothorax is a fatal disease causing acute and severe compromise of patients’ ventilation and circulation, in which case immediate decompression is necessary for better prognosis [6]. A previous study has shown that the incidence of tension pneumothorax varies from 0.2% to 1.7% in patients with prehospital trauma. Several trauma guidelines recommend needle thoracostomy as a life-saving intervention, with placement in the second intercostal space at the midclavicular line (second ICS-MCL), the fourth intercostal space at the anterior axillary line (fourth ICS-AAL), or the fifth intercostal space at the midaxillary line (fifth ICS-MAL) for tension pneumothorax in a prehospital environment.
In 2018, according to newly issued the Advanced Trauma Life Support (ATLS) guidelines, the fifth ICS-MAL was suggested as the preferred place, and an 8 cm needle rather than the common 5 cm needle was proved to increase success rate of adults’ decompression.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 74
Incorrect
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What type of visual field defect are you likely to see in a lesion of the visual cortex:
Your Answer: Contralateral homonymous inferior quadrantanopia
Correct Answer: Contralateral homonymous hemianopia with macular sparing
Explanation:A lesion of the visual cortex will result in a contralateral homonymous hemianopia with macular sparing.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 75
Incorrect
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A 4-year old boy is taken to the emergency room after a sudden onset of coughing and wheezing. Further investigation reveals that he was drawing quietly in his room, when suddenly, he became anxious and started coughing. The parents also noted that the eraser on top of the pencil was missing.
A plain radiographic chest imaging is conducted, and confirmed foreign body aspiration.
Which of the following areas in the tracheobronchial tree is the most probable location of the aspirated eraser?Your Answer: Bifurcation of the trachea
Correct Answer: Right main bronchus
Explanation:In foreign body aspiration, the foreign body is more likely to enter the right main bronchus because it is shorter, wider and more vertical than the left main bronchus. In a patient who is standing or sitting, the foreign body tends to become lodged in the posterobasal segment of the inferior lobe of the right lung.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 76
Incorrect
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A 44 year old woman sustains an injury to the median nerve at the elbow after falling awkwardly. Which of the following clinical features are you LEAST likely to see on examination:
Your Answer: Weakness of pronation
Correct Answer: Loss of flexion of the medial two digits
Explanation:Flexion of the index and middle fingers at the IPJs is lost due to paralysis of the flexor digitorum superficialis and the lateral half of the flexor digitorum profundus. Flexion of the MCPJs of the index and middle fingers are lost due to paralysis of the lateral two lumbrical muscles. Flexion of the ring and little fingers are preserved as these are supported by the medial half of the flexor digitorum profundus and the medial two lumbrical muscles, innervated by the ulnar nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 77
Correct
-
Regarding the trachea, which of the following statements is INCORRECT:
Your Answer: A cricothyrotomy involves making an opening in the neck inferior to the cricoid cartilage.
Explanation:A cricothyrotomy involves making an opening in the median cricothyroid ligament (the medial part of the cricothyroid membrane), between the cricoid cartilage below and the thyroid cartilage above.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 78
Incorrect
-
A 16-year old boy is brought to the emergency room after suffering a traffic accident. Upon examination, there is noted ipsilateral loss of proprioception and vibration, ipsilateral motor loss, and contralateral loss of pain and temperature sensation. A spinal cord injury is given as a diagnosis.
Which of the following is the most probable cause of this manifestation?Your Answer: Anterior cord syndrome
Correct Answer: Brown-Séquard syndrome
Explanation:Brown-Sequard Hemicord Syndrome consists of ipsilateral weakness (corticospinal tract) and loss of joint position and vibratory sense (posterior column), with contralateral loss of pain and temperature sense (spinothalamic tract) one or two levels below the lesion. Segmental signs, such as radicular pain, muscle atrophy, or loss of a deep tendon reflex, are unilateral. Partial forms are more common than the fully developed syndrome.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 79
Incorrect
-
A 64-year-old lady attends the emergency department with a known brain tumour. Her left eye is directed outwards and downwards, she can't open it, and her pupil is fixed and dilated. The tumour is most likely compressing which of the following structures:
Your Answer: Superior cervical ganglion
Correct Answer: Oculomotor nerve
Explanation:The oculomotor nerve is the third cranial nerve. It is the main source of innervation to the extraocular muscles and also contains parasympathetic fibres which relay in the ciliary ganglion. Damage to the third cranial nerve may cause diplopia, pupil mydriasis, and/or upper eyelid ptosis. The clinical manifestations of third cranial nerve dysfunction reflect its constituent parts.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 80
Correct
-
Which of the following clinical features is most suggestive of a lesion of the temporal lobe:
Your Answer: Receptive dysphasia
Explanation:Damage to the Wernicke’s speech area in the temporal lobe can result in a receptive dysphasia. Hemispatial neglect is most likely to occur in a lesion of the parietal lobe. Homonymous hemianopia is most likely to occur in a lesion of the occipital lobe. Expressive dysphasia is most likely to occur in a lesion of the Broca speech area in the frontal lobe. Conjugate eye deviation towards the side of the lesion is most likely to occur in a lesion of the frontal lobe.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 81
Incorrect
-
Which of the following would you NOT expect from a deep fibular nerve palsy:
Your Answer: High-steppage gait
Correct Answer: Loss of sensation over heel
Explanation:Damage to the deep fibular nerve results in loss of dorsiflexion of the ankle, with resultant foot drop with high-stepping gait, loss of toe extension, weakness of foot inversion and loss of sensation over the webspace between the 1st and 2nd toes.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 82
Correct
-
When inserting a Seldinger chest drain for management of pneumothorax, the 'safe triangle' should be identified. Which of the following forms the inferior border of the 'safe triangle'?
Your Answer: 5 th intercostal space
Explanation:Care and management of the thoracostomy tubes (chest tubes) are subject to the direction and practice pattern of the responsible physician. Therefore, it is difficult to make a “one size fits all” set of instructions about the specific management recommendations for all chest tubes. It is recommended to discuss specific expectations for management with the patient’s attending physician. Facility specific Clinical Practice Guidelines (CPGs) may provide further guidance for one’s practice.
Placement of the appropriately sized chest tube is performed on the affected side. The typical landmark for placement is the 4th or 5th intercostal space (nipple line for males, inframammary fold for females) at the anterior axillary line. The space above the 5th intercostal space and below the base of the axilla that is bordered posteriorly by the trapezius and anteriorly by the pectoralis muscle has recently been described as the safe triangle. Tubes are positioned anteriorly for pneumothoraces and posteriorly for fluid processes.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 83
Incorrect
-
Which coronary artery is mostly likely affected if an ECG shows ST segment elevation in leads II, III and aVF, and ST segment depression in V1-V3?
Your Answer: Left marginal artery
Correct Answer: Right coronary artery
Explanation:A posterior wall MI occurs when posterior myocardial tissue (now termed inferobasilar), usually supplied by the posterior descending artery — a branch of the right coronary artery in 80% of individuals — acutely loses blood supply due to intracoronary thrombosis in that vessel. This frequently coincides with an inferior wall MI due to the shared blood supply.
The ECG findings of an acute posterior wall MI include the following:
1. ST segment depression (not elevation) in the septal and anterior precordial leads (V1-V4). This occurs because these ECG leads will see the MI backwards; the leads are placed anteriorly, but the myocardial injury is posterior.
2. A R/S wave ratio greater than 1 in leads V1 or V2.
3. ST elevation in the posterior leads of a posterior ECG (leads V7-V9). Suspicion for a posterior MI must remain high, especially if inferior ST segment elevation is also present.
4. ST segment elevation in the inferior leads (II, III and aVF) if an inferior MI is also present.The following ECG leads determine the location and vessels involved in myocardial infarction:
ECG Leads Location Vessel involved
V1-V2 Septal wall Left anterior descending
V3-V4 Anterior wall Left anterior descending
V5-V6 Lateral wall Left circumflex artery
II, III, aVF Inferior wall Right coronary artery (80%) or Left circumflex artery (20%)
I, aVL High lateral wall Left circumflex artery
V1, V4R Right ventricle Right coronary artery
V7-V9 Posterior wall Right coronary artery -
This question is part of the following fields:
- Anatomy
- Thorax
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Question 84
Incorrect
-
In inserting a nasogastric tube, which area is least likely to be a site of resistance when the tube goes from the nose to the stomach?
Your Answer: In the superior mediastinum where the oesophagus is crossed by the arch of the aorta
Correct Answer: In the posterior mediastinum where the oesophagus is crossed by the pulmonary trunk
Explanation:In the posterior mediastinum where the oesophagus is crossed by the pulmonary trunk offers the least resistance when nasogastric tube is inserted from the nose to the stomach.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 85
Correct
-
All of the following typically occurs as part of normal passive expiration except:
Your Answer: Contraction of the internal intercostal muscles
Explanation:Passive expiration is produced primarily by relaxation of the inspiratory muscles (diaphragm and external intercostal muscles) in addition to the elastic recoil of the lungs.
In expiration, several movements occur. There are:
1. depression of the sternal ends of the ribs (‘pump handle’ movement),
2. depression of the lateral shafts of the ribs (‘bucket handle’ movement) and
3. elevation of the diaphragm.
These result in a reduction of the thorax in an anteroposterior, transverse and vertical direction respectively. There is then a decreased intrathoracic volume and increased intrathoracic pressure and air is forced out of the lungs. -
This question is part of the following fields:
- Anatomy
- Thorax
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Question 86
Incorrect
-
Which of the following nerves supplies innervation to the extensor hallucis longus?
Your Answer: Common peroneal nerve
Correct Answer: Deep peroneal nerve
Explanation:Extensor hallucis longus is innervated by the deep fibular nerve (root value L5 and S1).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 87
Correct
-
Which of the following is where the rectovesical fascia is located:
Your Answer: Between the fundus of the bladder and the ampulla of the rectum
Explanation:In a triangular area between the vasa deferentia, the bladder and rectum are separated only by rectovesical fascia, commonly known as Denonvillier’s fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 88
Incorrect
-
A patient presents with pain in the wrist and a tingling in the hand. On examination Tinel's test is positive and you diagnose carpal tunnel syndrome. Regarding the carpal tunnel, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: The tendons of the flexor digitorum profundus, flexor digitorum superficialis and flexor pollicis longus lie within a single synovial sheath.
Explanation:Free movement of the tendons in the carpal tunnel is facilitated by synovial sheaths, which surround the tendons. All of the tendons of the flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) are contained within a single synovial sheath with a separate sheath enclosing the tendon of the flexor pollicis longus (FPL).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 89
Incorrect
-
A 26-year old female comes to the Emergency Room with complaints of bloody stools. She reports that prior to the passage of bloody stools, she experienced a sharp pain during defecation. Medical history reveals that she has been experiencing constipation for the past 2 weeks. After completing her medical history and physical examination, the attending physician gives an initial diagnosis of an anal fissure.
Which of the following nerves transmit painful sensation from the anus, resulting in the pain associated with anal fissure?Your Answer:
Correct Answer: Inferior rectal nerve
Explanation:A fissure in ano is a tear in the anoderm distal to the dentate line. The pathophysiology of anal fissure is thought to be related to trauma from either the passage of hard stool or prolonged diarrhoea. A tear in the anoderm causes spasm of the internal anal sphincter, which results in pain, increased tearing, and decreased blood supply to the anoderm. The site of the anal fissure in the sensitive lower half of the anal canal, which is innervated by the inferior rectal nerve, results in reflex spasm of the external anal sphincter, aggravating the condition. Because of the intense pain, anal fissures may have to be examined under local anaesthesia.
The inferior rectal nerve is a branch of the pudendal nerve. This nerve runs medially across the ischiorectal fossa and supplies the external anal sphincter, the mucous membrane of the lower half of the anal canal, and the perianal skin.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 90
Incorrect
-
Which of the following nerves supplies the abductor pollicis brevis?
Your Answer:
Correct Answer: The recurrent branch of the median nerve
Explanation:Abductor pollicis brevis is innervated by the recurrent (thenar) branch of median nerve (root value C8 and T1).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 91
Incorrect
-
A 42-year-old man presented to the emergency room after an incident of slipping and falling onto his back and left hip. Upon physical examination, it was noted that he has pain on hip adduction, but normal hip flexion.
Which of the following muscles was most likely injured in this case?Your Answer:
Correct Answer: Pectineus
Explanation:The hip adductors are a group of five muscles located in the medial compartment of the thigh. These muscles are the adductor longus, adductor brevis, adductor magnus, gracilis, and pectineus.
The hip flexors consist of 5 key muscles that contribute to hip flexion: iliacus, psoas, pectineus, rectus femoris, and sartorius.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 92
Incorrect
-
A 22-year-old student presents with severe headache accompanied with nausea and vomiting. Upon observation and examination, it was noted that he is febrile and Kernig's sign is positive. A diagnosis of meningitis was suspected and a lumbar puncture was to be performed.
Which of the following statements regarding meningitis is true?Your Answer:
Correct Answer: The dura mater is the outermost layer
Explanation:Meningitis is defined as the inflammation of the meninges due to an infection caused by a bacteria or a virus. Symptoms usually include stiffness of the neck, headache, and fever.
There are 3 meningeal layers that surround the spinal cord and they are the dura mater, arachnoid matter, and pia mater.The dura mater is the outermost and thickest layer out of all the 3 layers.
The arachnoid atter is the middle layer, and is very thin.
The third and deepest meningeal layer is the pia mater that is bound tightly to the surface of the spinal cord. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 93
Incorrect
-
A 25-year-old guy who has had a knee-high plaster cast on his left leg for the past 5 weeks arrives at the emergency department complaining of numbness on the dorsum of his left foot and an inability to dorsiflex or evert his foot. You know that his symptoms are due to fibular nerve compression. Where is the fibular nerve located?
Your Answer:
Correct Answer: Neck of fibula
Explanation:Dorsiflexion and eversion of the foot are innervated by the deep fibular nerve and the superficial fibular nerve, respectively.
The common fibular nerve runs obliquely downward along the lateral border of the popliteal fossa (medial to the biceps femoris) before branching at the neck of the fibula.
Thus, it is prone to being affected during an impact injury or fracture to the bone or leg. Casts that are placed too high can also compress the fibular nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 94
Incorrect
-
A 55-year-old woman was complaining of headaches. On examination, the patient is found to have weakness on the left side of her body and her eyes are deviated towards the right hand side. These are signs of damage to which of the following areas?
Your Answer:
Correct Answer: Frontal lobe
Explanation:Some potential symptoms of frontal lobe damage can include loss of movement, either partial or complete, on the opposite side of the body.
In the patient’s case, it is a result of motor cortex damage on the right side since her left side of the body is affected. The conjugate eye deviation symptom towards the side of the lesion is a result of damage to the frontal eye field.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 95
Incorrect
-
A 43-year old male is taken to the Emergency Room for a lacerated wound on the abdomen, situated above the umbilicus. A short segment of the small bowel has herniated through the wound.
Which of these anatomic structures is the deepest structure injured in the case above?Your Answer:
Correct Answer: Transversalis fascia
Explanation:The following structures are the layers of the anterior abdominal wall from the most superficial to the deepest layer:
Skin
Fatty layer of the superficial fascia (Camper’s fascia)
Membranous layer of the superficial fascia (Scarpa’s fascia)
Aponeurosis of the external and internal oblique muscles
Rectus abdominis muscle
Aponeurosis of the internal oblique and transversus abdominis
Fascia transversalis
Extraperitoneal fat
Parietal peritoneum -
This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 96
Incorrect
-
The most common site of ectopic pregnancy is?
Your Answer:
Correct Answer: Ampulla of Fallopian tube
Explanation:Nearly 95% of ectopic pregnancies are implanted in the various segments of the fallopian tube and give rise to fimbrial, ampullary, isthmic, or interstitial tubal pregnancies. The ampulla is the most frequent site, followed by the isthmus. The remaining 5% of non tubal ectopic pregnancies implant in the ovary, peritoneal cavity, cervix, or prior caesarean scar.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 97
Incorrect
-
You are reviewing a patient complaining of loss of vision. Previous images shows a lesion at the optic chiasm. What type of visual field defect are you most likely to see in a lesion at the optic chiasm:
Your Answer:
Correct Answer: Bitemporal hemianopia
Explanation:A lesion at the optic chiasm will result in a bitemporal hemianopia.
A lesion of the optic nerve will result in ipsilateral monocular visual loss.
A lesion of the optic tract will result in a contralateral homonymous hemianopia. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 98
Incorrect
-
In which part of the gastrointestinal tract is Meckel's diverticulum commonly located?
Your Answer:
Correct Answer: Ileum
Explanation:Meckel’s diverticulum is the most prevalent congenital anomaly of the gastrointestinal tract, affecting approximately 2% of the general population. Meckel’s diverticulum are designated true diverticula because their walls contain all the layers found in normal small intestine. Their location varies among individual patients, but they are usually found in the ileum within 100 cm of the ileocecal valve.
Approximately 60% of Meckel’s diverticulum contain heterotopic mucosa, of which over 60% consist of gastric mucosa. Pancreatic acini are the next most common; others include Brunner’s glands, pancreatic islets, colonic mucosa, endometriosis, and hepatobiliary tissues.
A useful, although crude, mnemonic describing Meckel’s diverticulum is the “rule of twos”: 2% prevalence, 2:1 male predominance, location 2 feet proximal to the ileocecal valve in adults, and half of those who are symptomatic are under 2 years of age.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 99
Incorrect
-
Regarding codeine, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: There is a reduced risk of toxicity in patients who are ultra-rapid metabolisers of codeine.
Explanation:Codeine phosphate is a weak opioid and can be used for the relief of mild to moderate pain where other painkillers such as paracetamol or ibuprofen have proved ineffective.Codeine is metabolised to morphine which is responsible for its therapeutic effects. Codeine 240 mg is approximately equivalent to 30 mg of morphine. The capacity to metabolise codeine can vary considerably between individuals; there is a marked increase in morphine toxicity in people who are ultra rapid metabolisers, and reduced therapeutic effect in poor codeine metabolisers. Codeine is contraindicated in patients of any age who are known to be ultra-rapid metabolisers of codeine (CYP2D6 ultra-rapid metabolisers).Codeine is also contraindicated in children under 12, and in children of any age who undergo the removal of tonsils or adenoids for the treatment of obstructive sleep apnoea due to reports of morphine toxicity.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 100
Incorrect
-
Gallstones are commonly found lodged in which of the following parts of the gallbladder?
Your Answer:
Correct Answer: Neck
Explanation:There is a significant association between the presence of Hartmann’s pouch and gallbladder stones. It is the most common location for gallstones to become lodged and cause cholestasis.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 101
Incorrect
-
Which of the following is NOT a side effect of phenytoin:
Your Answer:
Correct Answer: Ototoxicity
Explanation:Adverse effects of phenytoin include:
Nausea and vomiting
Drowsiness, lethargy, and loss of concentration
Headache, dizziness, tremor, nystagmus and ataxia
Gum enlargement or overgrowth
Coarsening of facial features, acne and hirsutism
Skin rashes
Blood disorders -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 102
Incorrect
-
A 29 year old woman is unable to invert her foot after sustaining an injury to her leg playing water-polo. Which of the following nerves are most likely damaged:
Your Answer:
Correct Answer: Tibial and deep fibular nerve
Explanation:Inversion of the foot is primarily produced by the tibialis anterior and the tibialis posterior muscles, innervated by the deep fibular nerve and the tibial nerve respectively.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 103
Incorrect
-
Thyroid cancer has spread to the regional lymph nodes of a patient as seen in a staging CT scan.
The lymph from the thyroid gland will drain directly to which of the following nodes?Your Answer:
Correct Answer: Deep lateral cervical lymph nodes
Explanation:Lymphatic drainage of the thyroid gland involves the lower deep cervical, prelaryngeal, pretracheal, and paratracheal nodes. The paratracheal and lower deep cervical nodes, specifically, receive lymphatic drainage from the isthmus and the inferior lateral lobes. The superior portions of the thyroid gland drain into the superior pretracheal and cervical nodes.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 104
Incorrect
-
You note that the prostate of a 60-year-old patient is enlarged during the examination. You suspect BPH. Anatomically, the prostate has four main lobes. Which of the lobes is affected by benign prostatic hypertrophy?
Your Answer:
Correct Answer: Median lobe
Explanation:Benign prostatic hyperplasia (BPH), also known as benign prostatic hypertrophy, is characterized by an enlarged prostate gland.
The prostate is divided into four major lobes. The median lobe is the most commonly affected by benign prostatic enlargement, resulting in urethral obstruction and urine symptoms.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 105
Incorrect
-
A tumour compresses the jugular foramen of a 50-year-old patient. Compression of several nerves in the jugular foramen will result in which of the following complications?
Your Answer:
Correct Answer: Loss of gag reflex
Explanation:The glossopharyngeal nerve, which is responsible for the afferent pathway of the gag reflex, the vagus nerve, which is responsible for the efferent pathway of the gag reflex, and the spinal accessory nerve all exit the skull through the jugular foramen. These nerves are most frequently affected if the jugular foramen is compressed. As a result, the patient’s gag reflex is impaired.
The vestibulocochlear nerve is primarily responsible for hearing. The trigeminal nerve provides sensation in the face. The facial nerve innervates the muscles of face expression (including those responsible for closing the eye). Tongue motions are controlled mostly by the hypoglossal nerve.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 106
Incorrect
-
A 33-year-old woman demonstrates right-sided superior homonymous quadrantanopia upon visual field testing. A diagnosis of a brain tumour has been established.
Which of the following anatomical points in the visual pathway has the lesion occurred?Your Answer:
Correct Answer: Lower optic radiation
Explanation:Homonymous quadrantanopia is not a disease; it is a clinical finding that points towards a lesion of the optic radiations coursing through the temporal lobe.
Homonymous superior quadrantanopia is caused by damage to the contralateral inferior parts of the posterior visual pathway: the inferior optic radiation (temporal Meyer loop), or the inferior part of the occipital visual cortex below the calcarine fissure. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 107
Incorrect
-
This anatomic part lies at the heart of the tooth.
Your Answer:
Correct Answer: The pulp cavity
Explanation:Within the central portion of the tooth lies the dental pulp. The pulp chamber provides mechanical support and functions as a barrier from external stimuli and the oral microbiome. The dental pulp is a unique tissue that is richly innervated and has an extensive microvascular network. Maintaining its vitality increases both the mechanical resistance of the tooth and the long-term survival. The junctional epithelium forms a band around the tooth at the base of the gingival sulcus, sealing off the periodontal tissues from the oral cavity.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 108
Incorrect
-
When the breast cancer of a 60-year old patient metastasizes and compresses the intervertebral foramina between the fourth and fifth cervical vertebrae, as well as the fourth and fifth thoracic vertebrae, this causes back pain. Which pair of nerves is most likely affected?
Your Answer:
Correct Answer: Fifth cervical and fourth thoracic nerves
Explanation:The fifth cervical nerve passes between the fourth and fifth cervical vertebrae, and the fourth thoracic nerve passes between the fourth and fifth thoracic vertebrae. Therefore, when the cancer metastasizes in this area, they are most likely affected.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 109
Incorrect
-
Which of the following is most likely affected in De Quervain's tenosynovitis?
Your Answer:
Correct Answer: Extensor pollicis brevis
Explanation:De Quervain tenosynovitis is named after the Swiss surgeon, Fritz de Quervain, who first described it in 1895. It is a condition which involves tendon entrapment affecting the first dorsal compartment of the wrist. With this condition thickening of the tendon sheaths around the abductor pollicis longus and extensor pollicis brevis develops where the tendons pass in through the fibro-osseous tunnel located along the radial styloid at the distal wrist. Pain is exacerbated by thumb movement and radial and ulnar deviation of the wrist.
The estimated prevalence of de Quervain tenosynovitis is about 0.5% in men and 1.3% in women with peak prevalence among those in their forties and fifties. It may be seen more commonly in individuals with a history of medial or lateral epicondylitis. Bilateral involvement is often reported in new mothers or child care providers in whom spontaneous resolution typically occurs once lifting of the child is less frequent.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 110
Incorrect
-
A 70-year-old man has a resting tremor, rigidity, bradykinesia, and a shuffling gait. Parkinson's disease is caused by one of the following mechanisms:
Your Answer:
Correct Answer: Loss of dopaminergic neurons in the substantia nigra
Explanation:Parkinson’s disease (PD) is one of the most common neurologic disorders, affecting approximately 1% of individuals older than 60 years and causing progressive disability that can be slowed but not halted, by treatment. The 2 major neuropathologic findings in Parkinson’s disease are loss of pigmented dopaminergic neurons of the substantia nigra pars compacta and the presence of Lewy bodies and Lewy neurites. See the images below.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 111
Incorrect
-
The pelvic bone is formed by which of the following:
Your Answer:
Correct Answer: Ilium, ischium and pubis
Explanation:Each pelvic bone is formed by three elements: the ilium (superiorly), the pubis (anteroinferiorly) and the ischium (posteroinferiorly).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 112
Incorrect
-
Which of the following nerves provides sensory innervation to the anteromedial and anterosuperior aspects of the external ear?
Your Answer:
Correct Answer: Auriculotemporal nerve
Explanation:Sensory innervation to the external ear is supplied by both cranial and spinal nerves. Branches of the trigeminal, facial, and vagus nerves (CN V, VII, X) are the cranial nerve components, while the lesser occipital (C2, C3) and greater auricular (C2, C3) nerves are the spinal nerve components involved. The lateral surface of the tympanic membrane, the external auditory canal, and the external acoustic meatus are all innervated by nervus intermedius (a branch of CN VII), the auriculotemporal nerve (CN V3), and the auricular branch of the vagus nerve. The concha receives split innervation from nervus intermedius, the auricular branch of the vagus nerve, and the greater auricular (spinal) nerve. Beyond the concha, the anteromedial and anterosuperior parts of the pinna are innervated by the auriculotemporal nerve, and a portion of the lateral helix by the lesser occipital nerve. The greater auricular nerve provides innervation to the area of the pinna inferolateral to the lobule.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 113
Incorrect
-
A 25-year-old athlete suffers an injury to the nerve that innervates the gluteus minimus muscle.
Which of the following nerves innervates the gluteus minimus muscle?Your Answer:
Correct Answer: Superior gluteal nerve
Explanation:Gluteus minimus is the smallest muscle of the glutei. It is located just beneath the gluteus medius muscle. Gluteus minimus predominantly acts as a hip stabilizer and abductor of the hip.
The superior gluteal nerve innervates the gluteus minimus. -
This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 114
Incorrect
-
A 68-year-old man with BPH presents to the emergency department in significant pain secondary to urinary retention. What is the location of the neuronal cell bodies that are responsible for urinary bladder discomfort sensation?
Your Answer:
Correct Answer: Dorsal root ganglia of spinal cord levels S2, S3 and S4
Explanation:The activation of stretch receptors with visceral afferents relayed through the pelvic nerve plexus and into the pelvic splanchnic nerves causes bladder pain. The sensory fibres of spinal nerves S2 – S4 enter the dorsal root ganglia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 115
Incorrect
-
A 30-year old male is taken to the emergency room after suffering a blunt trauma to the abdomen. He is complaining of severe abdominal pain, however all his other vital signs remain stable. A FAST scan is performed to assess for hemoperitoneum.
If hemoperitoneum is present, it is most likely to be observed in which of the following areas?Your Answer:
Correct Answer: Liver
Explanation:The Focused Assessment with Sonography in Trauma (FAST) is an ultrasound protocol developed to assess for hemoperitoneum and hemopericardium. Numerous studies have demonstrated sensitivities between 85% to 96% and specificities exceeding 98%.
The FAST exam evaluates four regions for pathologic fluid: (1) the right upper quadrant, (2) the subxiphoid (or subcostal) view, (3) the left upper quadrant, and (4) the suprapubic region.
The right upper quadrant (RUQ) visualizes the hepatorenal recess, also known as Morrison’s pouch, the right paracolic gutter, the hepato-diaphragmatic area, and the caudal edge of the left liver lobe. The probe is positioned in the sagittal orientation along the patient’s flank at the level of the 8 to 11 rib spaces. The hand is placed against the bed to ensure visualization of the retroperitoneal kidney. The RUQ view is the most likely to detect free fluid with an overall sensitivity of 66%. Recent retrospective evidence suggests the area along the caudal edge of the left lobe of the liver has the highest sensitivity, exceeding 93%.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 116
Incorrect
-
A patient suffers an injury to the nerve that innervates piriformis.
The piriformis muscle is innervated by which of the following nerves? Select ONE answer only.Your Answer:
Correct Answer: Nerve to piriformis
Explanation:Piriformis is innervated by the nerve to piriformis, which is a direct branch from the sacral plexus (S1 and S2).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 117
Incorrect
-
Which segment of the colon is most likely to be affected in diverticulitis?
Your Answer:
Correct Answer: Sigmoid colon
Explanation:Diverticulitis refers to inflammation and infection associated with a diverticulum and is estimated to occur in 10% to 25% of people with diverticulosis. Peridiverticular and pericolic infection results from a perforation (either macroscopic or microscopic) of a diverticulum, which leads to contamination, inflammation, and infection. The spectrum of disease ranges from mild, uncomplicated diverticulitis that can be treated in the outpatient setting, to free perforation and diffuse peritonitis that requires emergency laparotomy. Most patients present with left sided abdominal pain, with or without fever, and leucocytosis. The most common location for diverticulitis is the sigmoid colon.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 118
Incorrect
-
A 47-year old male comes to the out-patient department for a painful, right-sided groin mass. Medical history reveals a previous appendectomy 10 years prior. On physical examination, the mass can be reduced superiorly. Also, the mass extends to the scrotum. The initial diagnosis is a hernia.
Among the types of hernia, which is the most likely diagnosis of the case above?Your Answer:
Correct Answer: Indirect inguinal hernia
Explanation:Inguinal hernias can present with an array of different symptoms. Most patients present with a bulge in the groin area, or pain in the groin. Some will describe the pain or bulge that gets worse with physical activity or coughing. Symptoms may include a burning or pinching sensation in the groin. These sensations can radiate into the scrotum or down the leg. It is important to perform a thorough physical and history to rule out other causes of groin pain. At times an inguinal hernia can present with severe pain or obstructive symptoms caused by incarceration or strangulation of the hernia sac contents. A proper physical exam is essential in the diagnosis of an inguinal hernia. Physical examination is the best way to diagnose a hernia. The exam is best performed with the patient standing. Visual inspection of the inguinal area is conducted first to rule out obvious bulges or asymmetry in groin or scrotum. Next, the examiner palpates over the groin and scrotum to detect the presence of a hernia. The palpation of the inguinal canal is completed last. The examiner palpates through the scrotum and towards the external inguinal ring. The patient is then instructed to cough or perform a Valsalva manoeuvre. If a hernia is present, the examiner will be able to palpate a bulge that moves in and out as the patient increases intra abdominal pressure through coughing or Valsalva.
Groin hernias are categorized into 2 main categories: inguinal and femoral.
Inguinal hernias are further subdivided into direct and indirect. An indirect hernia occurs when abdominal contents protrude through the internal inguinal ring and into the inguinal canal. This occurs lateral to the inferior epigastric vessels. The hernia contents may extend into the scrotum, and can be reduced superiorly then superolaterally. A direct inguinal hernia is protrusion of abdominal contents through the transversalis fascia within Hesselbach’s triangle. The borders of Hesselbach’s triangle are the inferior epigastric vessels superolaterally, the rectus sheath medially, and inguinal ligament inferiorly.
A femoral hernia is a protrusion into the femoral ring. The borders of the femoral ring are the femoral vein laterally, Cooper’s ligament posteriorly, the iliopubic tract/inguinal ligament anteriorly and lacunar ligament medially.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 119
Incorrect
-
A 29-year-old man has been complaining about his recent headaches. Detailed history was taken and a neurological examination was performed.
Which of the following cranial nerves is correctly paired with its lesion?Your Answer:
Correct Answer: The oculomotor nerve: the eye appears to look ‘down and out’
Explanation:The following are the lesions of the cranial nerves:
1. Olfactory nerve (I)
Reduced taste and smell, but not to ammonia which stimulates the pain fibres carried in the trigeminal nerve2. Optic nerve (II)
Manifested by visual field defects, pupillary abnormalities, optic neuritis, optic atrophy, papilledema3. Oculomotor nerve (III)
A fixed, dilated pupil which doesn’t accommodate, ptosis, complete internal ophthalmoplegia (masked by ptosis), unopposed lateral rectus causes outward deviation of the eye. If the ocular sympathetic fibres are also affected behind the orbit, the pupil will be fixed but not dilated.4. Trochlear nerve (IV)
Diplopia due to weakness of downward and inward eye movement. The most common cause of a pure vertical diplopia. The patient tends to compensate by tilting the head away from the affected side.5. Trigeminal nerve (V)
Reduced sensation or dysesthesia over the affected area. Weakness of jaw clenching and side-to-side movement. If there is a lower motor neuron (LMN) lesion, the jaw deviates to the weak side when the mouth is opened. There may be fasciculation of temporalis and masseter.6. Abducens nerve (VI)
Inability to look laterally. The eye is deviated medially because of unopposed action of the medial rectus muscle.7. Facial nerve (VII)
Facial weakness. In an LMN lesion the forehead is paralysed – the final common pathway to the muscles is destroyed; whereas the upper facial muscles are partially spared in an upper motor neurone (UMN) lesion because of alternative pathways in the brainstem. There appear to be different pathways for voluntary and emotional movement. CVAs usually weaken voluntary movement, often sparing involuntary movements (e.g., spontaneous smiling). The much rarer selective loss of emotional movement is called mimic paralysis and is usually due to a frontal or thalamic lesion.8. Vestibulocochlear nerve (VIII)
Unilateral sensorineural deafness, tinnitus. Slow-growing lesions seldom present with vestibular symptoms as compensation has time to occur.9. Glossopharyngeal nerve (IX)
Unilateral lesions do not cause any deficit because of bilateral corticobulbar connections. Bilateral lesions result in pseudobulbar palsy. These nerves are closely interlinked.10. Vagus nerve (X)
Palatal weakness can cause ‘nasal speech’ and nasal regurgitation of food. The palate moves asymmetrically when the patient says ‘ahh’. Recurrent nerve palsy results in hoarseness, loss of volume and ‘bovine cough’.11. Accessory nerve (XI)
Weakness and wasting of sternocleidomastoid and trapezius muscles12.Hypoglossal nerve (XII)
An LMN lesion produces wasting of the ipsilateral side of the tongue, with fasciculation; and on attempted protrusion the tongue deviates towards the affected side, but the tongue deviates away from the side of a central lesion. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 120
Incorrect
-
A 43-year-old woman presented to the emergency room after an incident of slipping and falling onto her back and left hip. Upon physical examination, it was noted that she has pain on hip abduction, but normal hip extension.
Which of the following muscles was most likely injured in this case?Your Answer:
Correct Answer: Gluteus medius
Explanation:The primary hip extensors are the gluteus maximus and the hamstrings such as the long head of the biceps femoris, the semitendinosus, and the semimembranosus. The extensor head of the adductor magnus is also considered a primary hip extensor.
The hip abductor muscle group is located on the lateral thigh. The primary hip abductor muscles include the gluteus medius, gluteus minimus, and tensor fasciae latae.
The secondary hip abductors include the piriformis, sartorius, and superior fibres of the gluteus maximus. -
This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 121
Incorrect
-
Carbamazepine is contraindicated in which of the following:
Your Answer:
Correct Answer: Atrioventricular block
Explanation:Carbamazepine is contraindicated in:
– People with known hypersensitivity to carbamazepine or structurally related drugs
– People with atrioventricular block (may suppress AV conduction and ventricular automaticity)
– People with a history of bone marrow depression (risk of agranulocytosis and aplastic anaemia)
– People with a history of acute porphyrias
– People taking a monoamine oxidase inhibitor (risk of serotonin syndrome) -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 122
Incorrect
-
The common bile duct drains into the duodenum in which of the following regions:
Your Answer:
Correct Answer: Second part of the duodenum
Explanation:As the common bile duct descends, it passes posterior to the first part of the duodenum before joining with the pancreatic duct from the pancreas, forming the hepatopancreatic ampulla (ampulla of Vater) at the major duodenal papilla, located in the second part of the duodenum. Surrounding the ampulla is the sphincter of Oddi, a collection of smooth muscle which can open to allow bile and pancreatic fluid to empty into the duodenum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 123
Incorrect
-
CSF is reabsorbed from subarachnoid space via which of the following structures:
Your Answer:
Correct Answer: Arachnoid granulations
Explanation:From the subarachnoid cisterns in the subarachnoid space, CSF is reabsorbed via arachnoid granulations which protrude into the dura mater, into the dural venous sinuses and from here back into the circulation.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 124
Incorrect
-
A 32-year-old woman suffers a deep wound to her thigh while she was climbing over a barbed wire fence. As a consequence of her injury, the nerve that was severed innervates the gracilis muscle.
In which of the following nerves is the gracilis muscle innervated by?Your Answer:
Correct Answer: Anterior branch of the obturator nerve
Explanation:The gracilis muscles is innervated by the anterior branch of the obturator nerve (L2-L4).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 125
Incorrect
-
An 82 year old man has fever, left sided abdominal and back pain and presents to the emergency room. Imaging reveals a large perinephric abscess. Which of the following most likely describes the fluid location:
Your Answer:
Correct Answer: Between the renal capsule and the renal fascia
Explanation:The perinephric fat is immediately external to the renal capsule and completely surrounds the kidney. The renal fascia surrounds the perinephric fat and the paranephric fat is external to the renal fascia. The location of a perinephric abscess is in the perinephric fat between the renal capsule and the renal fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 126
Incorrect
-
Which of the following occurs primarily to produce passive expiration:
Your Answer:
Correct Answer: Relaxation of diaphragm and external intercostal muscles
Explanation:Passive expiration is produced primarily by relaxation of the inspiratory muscles (diaphragm and external intercostal muscles) and the elastic recoil of the lungs. In expiration, depression of the sternal ends of the ribs (‘pump handle’ movement), depression of the lateral shafts of the ribs (‘bucket handle’ movement) and elevation of the diaphragm result in a reduction of the thorax in an anteroposterior, transverse and vertical direction respectively. This results in a decreased intrathoracic volume and increased intrathoracic pressure and thus air is forced out of the lungs.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 127
Incorrect
-
Which of the following clinical features would you least expect to see in a lesion of the frontal lobe:
Your Answer:
Correct Answer: Contralateral homonymous hemianopia with macular sparing
Explanation:Contralateral homonymous hemianopia with macular sparing results from damage to the primary visual cortex of the occipital lobe. Incontinence may occur due to damage of the cortical micturition centre in the prefrontal cortex. Primitive reflexes and inability to problem solve may occur due to damage to the prefrontal cortex. Motor weakness of the contralateral limb with UMN signs may occur due to damage of the primary motor cortex.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 128
Incorrect
-
Which of the following muscles is NOT involved in depression of the mandible:
Your Answer:
Correct Answer: Masseter
Explanation:Depression of the mandible is generated by the digastric, geniohyoid, mylohyoid and lateral pterygoid muscles on both side, assisted by gravity. The lateral pterygoid muscles are also involved as this movement also involves protraction of the mandible. The masseter muscle is a powerful elevator of the mandible.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 129
Incorrect
-
Which of the following classes of drugs may predispose to lithium toxicity:
Your Answer:
Correct Answer: Thiazide diuretics
Explanation:Excretion of lithium may be reduced by thiazide diuretics, NSAIDs, and ACE inhibitors thus predisposing to lithium toxicity. Loop diuretics also cause lithium retention but are less likely to result in lithium toxicity.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 130
Incorrect
-
Which of the following muscles is least likely to be involved in forceful expiration:
Your Answer:
Correct Answer: External intercostal muscles
Explanation:Forceful expiration is primarily produced by the deeper thoracic muscles (internal and innermost intercostal muscles, subcostals and transversus thoracis) aided by contraction of the abdominal wall muscles which increase intra-abdominal pressure thus further reducing the volume of the thorax.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 131
Incorrect
-
A 26 year old horse rider has a bad fall and sustains a neck injury which displays the following signs:
- ability to extend the wrist against gravity
- paralysis of the hands, trunk, and legs
- absent sensation in the fingers and medial upper arms
- normal sensation over the thumbs
- absent sensation in chest, abdomen, and legs
What is the neurological level of the injury?Your Answer:
Correct Answer: C6
Explanation:C1 – C4 INJURY
Most severe of the spinal cord injury levels; paralysis in arms, hands, trunk and legs; patient may not be able to breathe on his or her own, cough, or control bowel or bladder movements; ability to speak is sometimes impaired or reducedC5 INJURY
Person can raise his or her arms and bend elbows; likely to have some or total paralysis of wrists, hands, trunk and legs; can speak and use diaphragm, but breathing will be weakenedC6 INJURY
Nerves affect wrist extension; paralysis in hands, trunk and legs, typically; should be able to bend wrists back; can speak and use diaphragm, but breathing will be weakenedC7 INJURY
Nerves control elbow extension and some finger extension; most can straighten their arm and have normal movement of their shouldersC8 INJURY
Nerves control some hand movement; should be able to grasp and release objectsC5 – Elbow flexors (biceps, brachialis)
C6 – Wrist extensors (extensor carpi radialis longus and brevis)
C7 – Elbow extensors (triceps)
C8 – Finger flexors (flexor digitorum profundus) to the middle fingerC5 – Elbow flexed at 90 degrees, arm at the patient’s side and forearm supinated
C6 – Wrist in full extension
C7 – Shoulder is neutral rotation, adducted and in 90 degrees of flexion with elbow in 45 degrees of flexion
C8 –Full flexed position of the distal phalanx with the proximal finger joints stabilized in a extended position -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 132
Incorrect
-
A 38-year-old woman presented to the emergency room after an incident of slipping and falling onto her back and left hip. Upon physical examination, it was noted that she has pain on hip flexion, but normal hip adduction. Which of the following muscles was most likely injured in this case?
Your Answer:
Correct Answer: Sartorius
Explanation:The hip adductors are a group of five muscles located in the medial compartment of the thigh. These muscles are the adductor longus, adductor brevis, adductor magnus, gracilis, and pectineus.
The hip flexors consist of 5 key muscles that contribute to hip flexion: iliacus, psoas, pectineus, rectus femoris, and sartorius.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 133
Incorrect
-
Which of the following body location is the appropriate site to apply pressure when performing a carotid sinus massage?
Your Answer:
Correct Answer: Thyroid cartilage
Explanation:The common carotid artery runs through the neck and divides into internal and external carotid arteries on both sides near the upper thyroid cartilage. In emergency situations, carotid sinus massage is also used to diagnose or treat paroxysmal supraventricular tachycardia.
During the procedure, to maximize access to the carotid artery, the patient is put in a supine position with the neck extended (i.e. elevating the chin away from the chest). The carotid sinus is normally positioned inferior to the angle of the jaw, near the arterial impulse, at the level of the thyroid cartilage. For 5 to 10 seconds, pressure is administered to one carotid sinus.
Although pulsatile pressure applied in a vigorous circular motion may be more effective, continuous pressure is preferred since it is more reproducible. If the predicted reaction is not obtained, the operation is repeated on the opposite side after a one- to two-minute wait.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 134
Incorrect
-
Which of the following statements accurately describes the extensor indicis muscle?
Your Answer:
Correct Answer: It lacks the juncturae tendinum
Explanation:Extensor indicis is a narrow, elongated muscle found in the posterior compartment of the forearm. It belongs to the deep extensors of the forearm, together with supinator, abductor pollicis longus, extensor pollicis longus, and extensor pollicis brevis muscles. It lacks the juncturae tendinum, which connects the extensor digitorum on the dorsal aspect of the hand.
Extensor indicis can be palpated by applying deep pressure over the lower part of the ulna while the index finger is extended. The main function of extensor indicis involves the extension of the index finger at the metacarpophalangeal and interphalangeal joints. As the index finger is one of the few fingers that have their own separate extensor muscle, it is able to extend independently from other fingers. Additionally, extensor indicis muscle produces a weak extension of the wrist.
Extensor indicis receives its nervous supply from posterior interosseous nerve, a branch of the radial nerve derived from spinal roots C7 and C8. The skin overlying the muscle is supplied by the same nerve, with fibres that stem from the spinal roots C6 and C7.
The superficial surface of the extensor indicis receives arterial blood supply from posterior interosseous branch of the ulnar artery, whereas its deep surface receives blood from perforating branches of the anterior interosseous artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 135
Incorrect
-
You are taking care of a 55-year-old male patient with a direct inguinal hernia. In explaining his hernia, which of the following layers was compromised and had resulted in his condition?
Your Answer:
Correct Answer: Transversalis fascia
Explanation:Direct inguinal hernias are most often caused by a weakness in the muscles of the abdominal wall that develops over time, or are due to straining or heavy lifting.
A direct inguinal hernia protrudes through the Transversalis fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 136
Incorrect
-
A 30 year old man presents to ED after a road traffic accident. Free intraperitoneal fluid is found on FAST (Focussed assessment for sonography in trauma) done in the supine position.
Which of these is most likely to be affected?
Your Answer:
Correct Answer: Hepatorenal recess
Explanation:Fluid accumulates most often in the hepatorenal pouch (of Morrison) in a supine patient. The hepatorenal pouch is located behind the liver and anterior to the right kidney and is the lowest space in the peritoneal cavity in the supine position.
Although the vesicouterine and rectouterine spaces are also potential spaces for fluid accumulation, fluid accumulation in them occur in the erect position.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 137
Incorrect
-
Which of the following muscles are primarily involved in passive inspiration:
Your Answer:
Correct Answer: Diaphragm and external intercostal muscles
Explanation:Passive inspiration is produced by contraction of the diaphragm (depressing the diaphragm) and the external intercostal muscles (elevating the ribs). In inspiration, elevation of the sternal ends of the ribs (‘pump handle’ movement), elevation of the lateral shafts of the ribs (‘bucket handle’ movement) and depression of the diaphragm result in expansion of the thorax in an anteroposterior, transverse and vertical direction respectively. This results in an increased intrathoracic volume and decreased intrathoracic pressure and thus air is drawn into the lungs.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 138
Incorrect
-
Regarding the brachioradialis muscle, which of the following statements is true?
Your Answer:
Correct Answer: It assists with supination of the forearm at the radioulnar joints
Explanation:Brachioradialis is a fusiform muscle located in the lateral part of the posterior forearm. Along with extensor carpi radialis brevis and extensor carpi radialis longus, it comprises the radial group of forearm muscles, which belong to the superficial layer of posterior forearm muscles. Although anatomically part of the posterior forearm muscles, which are known to be forearm extensors, brachioradialis’ fibre orientation enables it to rather flex the forearm, and aids in supination of the forearm at the radioulnar joint.
The brachioradialis muscle originates from the upper two-thirds of the lateral supracondylar ridge of humerus and the anterior surface of the lateral intermuscular septum of the arm. It slides over the lateral surface of the elbow joint, entering the anterolateral cubital area. The muscle fibres course inferiorly down the radial part of the anterior forearm, forming a thick tendon in approximately the middle of the forearm. This tendon then traverses the remainder of the forearm, inserting near the wrist, just proximal to the styloid process of radius.
Brachioradialis is innervated by the radial nerve (from the root values C5-C6) that stems from the posterior cord of the brachial plexus. Blood supply to the brachioradialis muscle comes from branches of the radial artery, radial recurrent artery and the radial collateral branch of the deep brachial artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 139
Incorrect
-
A patient with a stab wound to the axilla arrives to the emergency department. You notice weakness in elbow flexion and forearm supination during your assessment. Which of these nerves has been affected:
Your Answer:
Correct Answer: Musculocutaneous nerve
Explanation:The musculocutaneous nerve is relatively protected in the axilla, hence injury to it is uncommon. A stab wound in the axilla is the most prevalent source of damage. Because of the activities of the pectoralis major and deltoid, the brachioradialis, and the supinator muscles, arm flexion and forearm flexion and supination are diminished but not completely lost. Over the lateral part of the forearm, there is a lack of sensation.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 140
Incorrect
-
Which of the following tracts must be affected if a patient presents with decreased pain and temperature sensation in both lower extremities?
Your Answer:
Correct Answer: The lateral spinothalamic tract
Explanation:The main function of the spinothalamic tract is to carry pain and temperature via the lateral part of the pathway and crude touch via the anterior part. The spinothalamic tract pathway is an imperative sensory pathway in human survival because it enables one to move away from noxious stimuli by carrying pain and temperature information from the skin to the thalamus where it is processed and transmitted to the primary sensory cortex. The primary sensory cortex communicates with the primary motor cortex, which lies close to it, to generate rapid movement in response to potentially harmful stimuli. Furthermore, the spinothalamic tract has a role in responding to pruritogens, causing us to itch. Interestingly, itching suppresses the spinothalamic tract neuron response to the histamine effect.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 141
Incorrect
-
You are giving a teaching session to a group of final year medical students regarding lower limb neurology. Which of the following clinical features would be expected in an obturator nerve palsy:
Your Answer:
Correct Answer: Weakness of hip adduction
Explanation:Damage to the obturator nerve results in weak adduction of the hip with lateral swinging of the limb during walking due to unopposed abduction.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 142
Incorrect
-
Which of the following statements is correct about the extensor digitorum muscle?
Your Answer:
Correct Answer: It extends the medial four digits at the metacarpophalangeal joints
Explanation:Extensor digitorum is a long muscle located in the posterior compartment of the forearm. Together with the extensor carpi ulnaris and extensor digiti minimi, extensor carpi radialis longus and brevis as well as the brachioradialis, it belongs to the group of superficial extensors of the forearm. These muscles can be easily palpated in the lateral aspect of the posterior forearm, especially during the extension of hand when they are contracted.
Extensor digitorum runs from the lateral epicondyle of humerus to the medial four phalanges of the hand. In this way, it generates the pull for the extension of the four medial fingers in their metacarpophalangeal and both interphalangeal joints. Extensor digitorum also participates in the extension of the wrist.
Extensor digitorum is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).
Extensor digitorum is vascularized by the branches of three different arteries: (1) posterior interosseous artery, (2) radial recurrent artery, and (3) anterior interosseous artery. Anterior and posterior interosseous arteries are the branches of the common interosseous artery that arises from the ulnar artery. The radial recurrent artery is a branch of the radial artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 143
Incorrect
-
Which of the following anatomic structures will gallstones most likely lodge into, and cause cholestasis?
Your Answer:
Correct Answer: Hartmann’s pouch
Explanation:Hartmann’s pouch is a diverticulum that can occur at the neck of the gallbladder. It is one of the rarest congenital anomalies of the gallbladder. Hartmann’s gallbladder pouch is a frequent but inconsistent feature of normal and pathologic human gallbladders. It is caused by adhesions between the cystic duct and the neck of the gallbladder. As a result, it is classified as a morphologic rather than an anatomic entity.
There is a significant association between the presence of Hartmann’s pouch and gallbladder stones. It is the most common location for gallstones to become lodged and cause cholestasis.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 144
Incorrect
-
A 34-year-old man presented to the emergency room after being involved in a road traffic accident. Upon observation and examination, it was noted that he was hypotensive and has muffled heart sounds. It was suspected that he has pericardial effusion, so an emergency pericardiocentesis was to be performed.
In performing pericardiocentesis for suspected pericardial effusion, which of the following anatomical sites are at risk of being punctured?Your Answer:
Correct Answer: 1 cm below the left xiphocostal angle
Explanation:Pericardiocentesis is a procedure done to remove fluid build-up in the sac around the heart known as the pericardium. The pericardium can be tapped from almost any reasonable location on the chest wall. However, for the usual blind pericardiocentesis, the subxiphoid approach is preferred. Ideally, 2-D echocardiography is used to guide needle insertion and the subsequent path of the needle/catheter.
In the subxiphoid approach, the needle is inserted 1 cm inferior to the left xiphocostal angle with an angle of 30 degrees from the patient’s chest with a direction towards the left mid-clavicle.
The fingers may sense a distinct give when the needle penetrates the parietal pericardium. Successful removal of fluid confirms the needle’s position.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 145
Incorrect
-
Which of the following is NOT a typical side effect of opioid analgesics:
Your Answer:
Correct Answer: Diarrhoea
Explanation:All opioids have the potential to cause:
Gastrointestinal effects – Nausea, vomiting, constipation, difficulty with micturition (urinary retention), biliary spasm
Central nervous system effects – Sedation, euphoria, respiratory depression, miosis
Cardiovascular effects – Peripheral vasodilation, postural hypotension
Dependence and tolerance -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 146
Incorrect
-
An injury to which nerve affects innervation to the adductor portion of the adductor magnus?
Your Answer:
Correct Answer: Posterior branch of the obturator nerve
Explanation:The nerves that supply the adductor magnus muscle have an embryologic origin from the anterior divisions of the lumbosacral plexus and include the obturator nerve, posterior division (L2-4), and the tibial portion of the sciatic nerve (L4). It is innervated by the posterior division of the obturator nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 147
Incorrect
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The fracture of the medial epicondyle will cause damage to the ulnar nerve. Which of the following motions would be impaired by this type of injury?
Your Answer:
Correct Answer: Adduction of the thumb
Explanation:Fracture of the medial epicondyle is most likely to result in damage to the ulnar nerve.
The three hypothenar muscles, two medial lumbricals, seven interossei, the adductor pollicis, and the deep head of the flexor pollicis brevis are all innervated by the deep branch of the ulnar nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 148
Incorrect
-
Regarding paracetamol, which of the following statements is CORRECT:
Your Answer:
Correct Answer: It has anti-pyretic action.
Explanation:Paracetamol is a non-opioid analgesic, similar in efficacy to aspirin, with antipyretic properties but no anti-inflammatory properties. It is well absorbed orally and does not cause gastric irritation. Paracetamol is a suitable first-line choice for most people with mild-to-moderate pain, and for combination therapy.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 149
Incorrect
-
A suspicious growth on the posterior tongue of a 40-year-old man was discovered by his dentist and was immediately referred for possible oral cancer.
The lymph from the posterior tongue will drain to which of the following nodes?Your Answer:
Correct Answer: Deep cervical nodes
Explanation:Lymph from the medial anterior two thirds of the tongue travels to the deep cervical lymph nodes.
Lymph from the lateral anterior tongue goes to the submandibular nodes. -
This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 150
Incorrect
-
An 80-year-old woman with history of hypertension, diabetes, and ischemic stroke, presents with left-sided hemiplegia of the face, tongue, and limbs and right-sided deficits in motor eye activity. A CT scan was ordered and showed a right-sided stroke.
Branches of which of the following arteries are most likely implicated in the case?Your Answer:
Correct Answer: Basilar artery
Explanation:Weber syndrome is a midbrain stroke characterized by crossed hemiplegia along with oculomotor nerve deficits and it occurs with the occlusion of the median and/or paramedian perforating branches of the basilar artery.
Typical clinical findings include ipsilateral CN III palsy, ptosis, and mydriasis (such as damage to parasympathetic fibres of CN III) with contralateral hemiplegia.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 151
Incorrect
-
A patient suffers an injury to his thigh that damages the nerve that innervates pectineus.
Which of the following nerves has been damaged in this case? Select ONE answer only.Your Answer:
Correct Answer: Femoral nerve
Explanation:Pectineus is innervated by the femoral nerve. It may also receive a branch from the obturator nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 152
Incorrect
-
You are about to perform an emergency pericardiocentesis on a 26-year-old male who was involved in a car accident and is suspected of having cardiac tamponade due to signs of hypotension, muffled heart sounds, and distended neck veins. Where should you insert the needle to relieve tamponade?
Your Answer:
Correct Answer: Inferior and to the left of the xiphochondral junction
Explanation:Pericardiocentesis is a procedure that removes excess fluid from the pericardium. As a result, it’s used in cases of cardiac tamponade, which occurs when there’s too much fluid in the space around the heart.
During the procedure, a needle and a small catheter are inserted 1 to 2 cm inferior and to the left of the xiphochondral junction into the pericardial cavity.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 153
Incorrect
-
Regarding the lumbar plexus, which of the following is a direct muscular branch?
Your Answer:
Correct Answer: Nerve to quadratus lumborum
Explanation:The lumbar plexus gives rise to several branches which supply various muscles and regions of the posterior abdominal wall and lower limb. These branches include the Iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, femoral and obturator nerves.
In addition, the lumbar plexus gives off muscular branches from its roots, a branch to the lumbosacral trunk and occasionally an accessory obturator nerve.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 154
Incorrect
-
A patient sustains an injury to the proximal median nerve after falling through a glass door. Which of the following muscles would you not expect to be affected:
Your Answer:
Correct Answer: Flexor carpi ulnaris
Explanation:All of the muscles in the anterior forearm are innervated by the median nerve, except for the flexor carpi ulnaris and the medial half of the flexor digitorum profundus which are innervated by the ulnar nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 155
Incorrect
-
A 39-year-old guy comes to the emergency room with a persistent nasal bleed. You suspect the bleeding is coming from Little's area based on your examination. Which of the blood vessels listed below is most likely to be involved:
Your Answer:
Correct Answer: Sphenopalatine and superior labial arteries
Explanation:The Kiesselbach plexus is a vascular network formed by five arteries that supply oxygenated blood to the nasal septum, which refers to the wall separating the right and left sides of the nose. The five arteries that form the Kiesselbach plexus: the sphenopalatine artery, which branches from the maxillary artery originating behind the jawbone; the anterior ethmoidal artery, which branches from the ophthalmic artery behind the eye; the posterior ethmoidal artery, which also branches from the ophthalmic artery; the septal branch of the superior labial artery, which is a branch of the facial artery supplying blood to all of the superficial features of the face; and finally, the greater palatine artery, which is a terminal branch of the maxillary artery.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 156
Incorrect
-
Which of the following nerves is most important for eversion of the foot:
Your Answer:
Correct Answer: Superficial fibular nerve
Explanation:Eversion of the foot is primarily produced by the fibularis longus and fibularis brevis, both innervated by the superficial fibular nerve. The fibularis tertius, innervated by the deep fibular nerve, also assists in this action.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 157
Incorrect
-
An elderly man presents with bilateral lower facial swelling around the mandible and upper neck. A CT scan of his neck was performed and the results were conclusive with Ludwig's angina.
Which of the following spaces is most likely affected based on the case presented?Your Answer:
Correct Answer: Submandibular space
Explanation:Ludwig’s angina is life-threatening cellulitis of the soft tissue involving the floor of the mouth and neck. It involves three compartments of the floor of the mouth: the sublingual, submental, and submandibular.
Ludwig’s angina usually originates as a dental infection of the second or third mandibular molars. The infection begins in the subgingival pocket and spreads to the musculature of the floor of the mouth. It progresses below the mylohyoid line, indicating that it has moved to the sublingual space. As the roots of the second and third mandibular molars lie below this line, infection of these teeth will predispose to Ludwig’s angina. The infection spreads lingually rather than buccally because the lingual aspect of the tooth socket is thinner. It initially spreads to the sublingual space and progresses to the submandibular space.
The disease is usually polymicrobial, involving oral flora, both aerobes, and anaerobes. The most common organisms are Staphylococcus, Streptococcus, Peptostreptococcus, Fusobacterium, Bacteroides, and Actinomyces.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 158
Incorrect
-
Which lobe of the prostate gland is most commonly affected in benign prostatic hypertrophy?
Your Answer:
Correct Answer: Median
Explanation:Benign enlargement of the prostate is common in men older than 50 years. The cause is possibly an imbalance in the hormonal control of the gland. The median lobe of the gland enlarges upward and encroaches within the sphincter vesicae, located at the neck of the bladder. The leakage of urine into the prostatic urethra causes an intense reflex desire to micturate. The enlargement of the median and lateral lobes of the gland produces elongation and lateral compression and distortion of the urethra so that the patient experiences difficulty in passing urine and the stream is weak. Back-pressure effects on the ureters and both kidneys are a common complication. The enlargement of the uvula vesicae (owing to the enlarged median lobe) results in the formation of a pouch of stagnant urine behind the urethral orifice within the bladder. The stagnant urine frequently becomes infected, and the inflamed bladder (cystitis) adds to the patient’s symptoms.
In all operations on the prostate, the surgeon regards the prostatic venous plexus with respect. The veins have thin walls, are valveless, and are drained by several large trunks directly into the internal iliac veins. Damage to these veins can result in a severe haemorrhage.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 159
Incorrect
-
A 40-year-old woman presents with retrosternal central chest pain that she has been complaining about for the past two days. Upon deep inspiration and while lying flat, the pain worsens but relieved by sitting forwards. The pain radiates to both of her shoulders. The result of her ECG shows widespread concave ST-elevation and PR depression. A diagnosis of pericarditis is suspected.
Which of the following nerves is responsible for the pattern of her pain?Your Answer:
Correct Answer: Phrenic nerve
Explanation:Pericarditis is inflammation of the pericardial sac and is the most common pathologic process involving the pericardium. Frequently, pericardial inflammation can be accompanied by increased fluid accumulation within the pericardial sac forming a pericardial effusion, which may be serous, hemorrhagic or purulent depending on aetiology.
The classic presentation is with chest pain that is central, severe, pleuritic (worse on deep inspiration) and positional (improved by sitting up and leaning forward). The pain may also be radiating and may involve the ridges of the trapezius muscle if the phrenic nerve is inflamed as it traverses the pericardium.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 160
Incorrect
-
Which nerve innervates the brachioradialis muscle?
Your Answer:
Correct Answer: The radial nerve
Explanation:Brachioradialis is innervated by the radial nerve (from the root values C5-C6) that stems from the posterior cord of the brachial plexus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 161
Incorrect
-
A 30-year-old man suffers from an open fracture of his forearm. As a consequence of his injury, the nerve that innervates the pronator quadratus muscle was severed.
Which of the following statements regarding the pronator quadratus muscle is considered correct?Your Answer:
Correct Answer: Its deep fibres bind the radius and ulna together
Explanation:Pronator quadratus is a deep-seated, short, flat, and quadrilateral muscle with fibres running in a parallel direction.
It arises from the oblique ridge on the anterior surface of the distal fourth of the Ulna. It is inserted in lateral border and anterior surface of the distal fourth of the radius. It is innervated by the anterior interosseous nerve, a branch of the median nerve (C8-T1). It is vascularized by the anterior interosseous artery.
The action of the pronator quadratus muscle along with the pronator teres result in the pronation of the radioulnar joint. Contraction of this muscle pulls the distal end of the radius over the ulna, resulting in the pronation of the radioulnar joint
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 162
Incorrect
-
If a patient dislocated his right shoulder and has been referred to the orthopaedic outpatient department for a follow-up after a successful reduction, which of the following is the most important position for him to avoid holding his arm in until he is seen in the clinic?
Your Answer:
Correct Answer: Arm at 90 degrees to side with palm up
Explanation:The arm should be placed in a poly-sling that should be worn for about two weeks. A physiotherapist may give gentle movements for the arm to help in reducing stiffness and in relieving the pain. It is important that the patient must avoid positions that could cause re-dislocation.
The most important position to avoid is the arm being held out at 90 degrees to the side with the palm facing upwards, especially if a force is being applied. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 163
Incorrect
-
Which of the following is NOT a typical cerebellar sign:
Your Answer:
Correct Answer: Resting tremor
Explanation:An intention tremor is characteristic of cerebellar dysfunction. Resting tremor may be seen in Parkinsonism.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 164
Incorrect
-
Which of the following nerves is most likely associated with an anterior shoulder dislocation?
Your Answer:
Correct Answer: Axillary nerve
Explanation:In an anterior dislocation, the arm is an abducted and externally rotated position. In the externally rotated position, the posterosuperior aspect of the humeral head abuts and drives through the anteroinferior aspect of the glenoid rim. This can damage the humeral head, glenoid labrum, or both. An associated humeral head compression fracture is described as a Hill Sach’s lesion. If large enough, it can lead to locked dislocations that may require open reduction. The glenoid labrum is a fibrocartilaginous structure that rings the circumference of the glenoid fossa. Bankart lesions are injuries to the anteroinferior glenoid labrum complex and the most common capsulolabral injury. A bony Bankart lesion refers to an associated fracture of the glenoid rim. These capsulolabral lesions are risk factors for recurrent dislocation.
Axillary nerve injury is identified in about 42% of acute anterior shoulder dislocations. Nerve transection is rare, and traction injuries are more common. Arterial injury has also been described. The subclavian artery becomes the axillary artery after passing the first rib. The distal portion of the axillary artery is anatomically fixed and, therefore, susceptible to injury in anterior dislocations. Ischemic injury, including pseudoaneurysm and arterial laceration, is rare but carries marked morbidity if not quickly identified.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 165
Incorrect
-
A tumour is discovered behind the pectinate line during an examination of a 72-year-old patient with rectal bleeding. Which of the following is the lymphatic drainage of the pectinate line?
Your Answer:
Correct Answer: Superficial inguinal nodes
Explanation:The pectinate line is known as the watershed line because it divides the anal canal into two sections. Below the pectinate line, lymphatic drainage drains to the superficial inguinal lymph nodes.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 166
Incorrect
-
Which of the following nerves innervates the gastrocnemius muscle?
Your Answer:
Correct Answer: Tibial nerve
Explanation:The gastrocnemius is innervated by the anterior rami of S1 and S2 spinal nerves, carried by the tibial nerve into the posterior compartment of the leg.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 167
Incorrect
-
A patient with diplopia is found to have eye deviation downwards and outwards. The likely nerves that are affected are:
Your Answer:
Correct Answer: Oculomotor nerve
Explanation:The results of an oculomotor (CN III) nerve palsy are a depressed and abducted (down and out) eye, ptosis, diplopia, and a fixed and dilated pupil.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 168
Incorrect
-
Which coronary artery is mostly likely affected if an ECG shows a tombstone pattern in leads V2, V3 and V4?
Your Answer:
Correct Answer: Left anterior descending artery
Explanation:Tombstoning ST elevation myocardial infarction can be described as a STEMI characterized by tombstoning ST-segment elevation. This myocardial infarction is associated with extensive myocardial damage, reduced left ventricle function, serious hospital complications and poor prognosis. Tombstoning ECG pattern is a notion beyond morphological difference and is associated with more serious clinical results.
Studies have shown that tombstoning is more commonly found in anterior than non-anterior STEMI, thus, higher rates of left anterior descending artery disease are observed in patients with tombstoning pattern.
The following ECG leads determine the location and vessels involved in myocardial infarction:
ECG Leads Location Vessel involved
V1-V2 Septal wall Left anterior descending
V3-V4 Anterior wall Left anterior descending
V5-V6 Lateral wall Left circumflex artery
II, III, aVF Inferior wall Right coronary artery (80%) or Left circumflex artery (20%)
I, aVL High lateral wall Left circumflex artery
V1, V4R Right ventricle Right coronary artery
V7-V9 Posterior wall Right coronary artery -
This question is part of the following fields:
- Anatomy
- Thorax
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Question 169
Incorrect
-
A man presents to the emergency department with a hand laceration that has damaged the opponens digiti minimi muscle.
All of the following statements regarding the opponens digiti minimi muscle is considered correct, except:Your Answer:
Correct Answer: It is innervated by the superficial branch of the ulnar nerve
Explanation:Opponens digiti minimi (ODM) is an intrinsic muscle of the hand. It’s a triangular muscle that extends between the hamate bone (carpal bone) and the 5th metacarpal bone. It forms the hypothenar muscle group together with the abductor digiti minimi and flexor digiti minimi brevis, based on the medial side of the palm (hypothenar eminence). These muscles act together in moving the little finger. The opponens digiti minimi is responsible for flexion, lateral rotation and opposition of the little finger.
Its origin is the hook of hamate and flexor retinaculum. It inserts into the medial border of 5th metacarpal bone. It is innervated by the deep branch of the ulnar nerve, which stems from the brachial plexus (C8, T1 spinal nerves).
Its blood supply is by the deep palmar branch of ulnar artery and deep palmar arch, which is the terminal branch of the radial artery. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 170
Incorrect
-
During bedside rounds, an 82-year old female in the Medicine Ward complains of pain and tingling of all fingers of the right hand. The attending physician is considering carpal tunnel syndrome.
Which of the following is expected to undergo atrophy in carpal tunnel syndrome?
Your Answer:
Correct Answer: The thenar eminence
Explanation:Carpal tunnel syndrome (CTS) is an entrapment neuropathy caused by compression of the median nerve as it travels through the wrist’s carpal tunnel. It is the most common nerve entrapment neuropathy, accounting for 90% of all neuropathies. Early symptoms of carpal tunnel syndrome include pain, numbness, and paraesthesia’s. These symptoms typically present, with some variability, in the thumb, index finger, middle finger, and the radial half (thumb side) of the ring finger. Pain also can radiate up the affected arm. With further progression, hand weakness, decreased fine motor coordination, clumsiness, and thenar atrophy can occur.
The muscles innervated by the median nerve can be remembered using the mnemonic ‘LOAF’:
L– lateral two lumbricals
O– Opponens pollicis
A– Abductor pollicis
F– Flexor pollicis brevisIn the early presentation of the disease, symptoms most often present at night when lying down and are relieved during the day. With further progression of the disease, symptoms will also be present during the day, especially with certain repetitive activities, such as when drawing, typing, or playing video games. In more advanced disease, symptoms can be constant.
Typical occupations of patients with carpal tunnel syndrome include those who use computers for extended periods of time, those who use equipment that has vibration such as construction workers, and any other occupation requiring frequent, repetitive movement.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 171
Incorrect
-
In which of the following cases is intravenous phenytoin contraindicated?
Your Answer:
Correct Answer: Second degree heart block
Explanation:Phenytoin Contraindications include:
Hypersensitivity
Sinus bradycardia
Sinoatrial block
Second and third degree A-V block
Adams-Stokes syndrome
Concurrent use with delavirdine
History of prior acute hepatotoxicity attributable to phenytoin -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 172
Incorrect
-
Which of the following statements is false regarding the biceps brachii muscle?
Your Answer:
Correct Answer: It pronates the radioulnar joint in the forearm
Explanation:The biceps brachii muscle is one of the chief muscles of the arm. The origin at the scapula and the insertion into the radius of the biceps brachii means it can act on both the shoulder joint and the elbow joint, which is why this muscle participates in a few movements of the arm. It derives its name from its two heads which merge in one unique distal body, defining the unusual structure of the muscle.
The biceps brachii muscle is supplied by the musculocutaneous nerve (C5-C6), a branch of the brachial plexus.
Arterial supply to the biceps brachii muscle varies considerably, coming from up to eight vessels originating from the brachial artery in the middle third of the arm.
In the shoulder joint both muscle heads partially enforce opposite movements. The long head pulls the arm away from the trunk (abduction) and turns it inwards (inward rotation) whereas the short head pulls the arm back towards the trunk (adduction). When both heads contract simultaneously it leads to an arm bend (flexion). In the elbow joint the muscle bends the forearm (flexion) and rotates it outwards (supination). The supination is most powerful in a flexed elbow. In addition to the movement functions, the biceps has the important task to support the humeral head within the shoulder joint. Its antagonist is the triceps brachii in the posterior compartment of the arm.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 173
Incorrect
-
A 22 year old male has been stabbed and is brought to the ED with a stab wound to his upper limb. On examination, the patient is unable to flex the distal interphalangeal joints of the ring and little finger. However, the proximal interphalangeal joint is intact. The most likely affected nerve is which of the following, and at which level is this occurring?
Your Answer:
Correct Answer: Ulnar nerve at elbow
Explanation:The medial half of the flexor digitorum profundus is innervated by the ulnar nerve. Paralysis of this muscle results in loss of flexion at the distal interphalangeal joint of the ring and little finger.
Flexion at the proximal interphalangeal joint is preserved as this is a function of the flexor digitorum superficialis which is innervated by the median nerve.
The ulnar nerve is not correct as ulnar nerve injury at the wrist would not affect the long flexors, and the injury must have been more proximal. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 174
Incorrect
-
A patient has suffered a nerve injury that has caused weakness of the pectoralis minor muscle.
Pectoralis minor receives its innervation from which of the following nerves? Select ONE answer only.Your Answer:
Correct Answer: Medial pectoral nerve
Explanation:Pectoralis minor is a thin, triangular muscle that is situated in the upper chest. It is thinner and smaller than pectoralis major. It is innervated by the medial pectoral nerve.
The origin of pectoralis minor is the 3rdto the 5thribs, near the costal cartilages. It inserts into the medial border and superior surface of the coracoid process of the scapula.
The main action of pectoralis minor is to draw the scapula inferiorly and anteriorly against the thoracic wall. This serves to stabilise the scapula. -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 175
Incorrect
-
Due to a traffic accident, a male patient was unable to lift his arm, indicating an injury at the glenohumeral joint. Based on the patient’s current condition, which nerve or nerves are may likely damaged?
Your Answer:
Correct Answer: Axillary and suprascapular nerve
Explanation:A suprascapular nerve injury causes numbness in the shoulder, as well as weakness in abduction and external rotation.
Damage to the axillary nerve can result in shoulder or arm muscle weakness, as well as difficulty lifting the arm. This is because the deltoid and supraspinatus muscles, which are innervated by the axillary and suprascapular nerves, are responsible for abduction of the arm at the shoulder joint.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 176
Incorrect
-
Which of the following is a contraindication for aspirin?
Your Answer:
Correct Answer: Children under 16 years
Explanation:Aspirin contraindications include: hypersensitivity to NSAIDs; asthma, rhinitis, and nasal polyps; and usage in children or teens.
There is little evidence of allergic cross-reactivity for salicylates. However, due to similarities in chemical structure and/or pharmacologic activities, the possibility of cross-sensitivity cannot be completely ruled out. -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 177
Incorrect
-
Which of the following nerves has been damaged when a patient presents with a foot drop?
Your Answer:
Correct Answer: Common peroneal nerve
Explanation:The common peroneal nerve often referred to as the common fibular nerve, is a major nerve that innervates the lower extremity. It is one of the two major branches off the sciatic nerve and receives fibres from the posterior divisions of L4 through S2 nerve roots. The common peroneal nerve separates from the sciatic nerve in the distal posterior thigh proximal to the popliteal fossa. After branching off of the sciatic nerve, it continues down the thigh, running posteroinferior to the biceps femoris muscle, and crosses laterally to the head of the lateral gastrocnemius muscle through the posterior intermuscular septum. The nerve then curves around the fibular neck before dividing into two branches, the superficial peroneal nerve (SPN) and the deep peroneal nerve (DPN). The common peroneal nerve does not have any motor innervation before dividing; however, it provides sensory innervation to the lateral leg via the lateral sural nerve.
The superficial peroneal nerve innervates the lateral compartment of the leg, and the deep peroneal nerve innervates the anterior compartment of the leg and the dorsum of the foot. These two nerves are essential in the eversion of the foot and dorsiflexion of the foot, respectively. The superficial and deep peroneal nerves provide both motor and sensory innervation.
The most common presentation with common peroneal nerve injury or palsy is acute foot drop, although symptoms may be progressive and can include sensory loss or pain. Weakness in foot eversion may occur if the superficial peroneal nerve component is involved.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 178
Incorrect
-
Regarding the accessory nerve, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Accessory nerve palsy results in the inability to nod the head
Explanation:Accessory nerve palsy results in inability to shrug the shoulders and to rotate the head to look at the opposite side to the lesion.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 179
Incorrect
-
A 24-year-old man goes to the emergency department with a fever, headache, and swollen parotid glands that are excruciating. You have a suspicion that it is mumps. Which of the following nerves is causing the discomfort the patient is experiencing:
Your Answer:
Correct Answer: Auriculotemporal nerve
Explanation:The auriculotemporal nerve is irritated by mumps, which results in significant discomfort due to inflammation and swelling of the parotid gland, as well as the stretching of its capsule. Compression caused by swallowing or chewing exacerbates pain.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 180
Incorrect
-
Which of the following is true about the extensor carpi radialis longus?
Your Answer:
Correct Answer: It assists with abduction of the hand at the wrist
Explanation:The majority of extensor carpi radialis longus originates from the lateral supracondylar ridge of humerus (distal third) and anterior aspect of the lateral intermuscular septum of the arm. A small portion of its fibres originate from the common extensor tendon attached to the lateral epicondyle of humerus. The fibres unite into a muscle belly which extends approximately to the middle of the forearm. The muscle belly is then replaced by a flat tendon that travels distally along the lateral surface of the radius, together with the tendon of extensor carpi radialis brevis. Both tendons course towards the radial styloid process, deep to the tendons of abductor pollicis longus and extensor pollicis brevis muscles. Proximal to the wrist, the tendons of extensor carpi radialis longus and brevis pass behind the radial styloid process within a common synovial sheath and continue along the radial groove deep to the extensor retinaculum of the wrist. At this level, the tendon of extensor carpi radialis longus is crossed by the tendon of extensor pollicis longus, after which it inserts on the posterior aspect of the base of the second metacarpal bone. Some tendon slips can insert into the first and third metacarpal bones.
Extensor carpi radialis longus receives innervation from the radial nerve, with contributions mainly from spinal nerves C5-C8. The radial nerve is a branch of the brachial plexus.
Extensor carpi radialis longus receives blood supply mainly from the radial artery. It directly supplies the distal part of the muscle, while the rest of the muscle receives blood from one of its radial recurrent branches. The brachial artery also supplies a small portion of the muscle via the radial collateral artery.
Extensor carpi radialis longus primarily acts on the wrist joint to produce two major actions: (1) wrist extension by working synergistically with extensor carpi radialis brevis and extensor carpi ulnaris, and (2) hand abduction (radial deviation), with the help of flexor carpi radialis.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 181
Incorrect
-
You are taking care of a 55-year-old male patient who is a weightlifter. He is suspected of having a direct inguinal hernia. Where would this hernia appear?
Your Answer:
Correct Answer: Medial to the inferior epigastric artery
Explanation:A direct inguinal hernia is a form of groin hernia that occurs when abdominal viscera protrude through a weakness in the posterior wall of the inguinal canal, notably through Hesselbach’s triangle, medial to the inferior epigastric veins.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 182
Incorrect
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A newborn baby girl is delivered vaginally to a 19-year old female, however with complications due to cephalopelvic disproportion. Upon examination by the attending paediatrician, there is a notable 'claw hand' deformity of the left, and sensory loss of the ulnar aspect of the left distal upper extremity.
What is the most probable diagnosis of the case above?Your Answer:
Correct Answer: Klumpke’s palsy
Explanation:Klumpke palsy, named after Augusta Dejerine-Klumpke, is a neuropathy involving the lower brachial plexus. In contrast, the more common Erb–Duchenne palsy involves the more cephalic portion of the brachial plexus C5 to C6. The brachial plexus is a bundle of individual nerves that exit between the anterior and middle scalene muscles in the anterior lateral and basal portion of the neck. Although the most common anatomical presentation of the brachial plexus is between the anterior and middle scalene, there are variations, with the most common being penetration of the anterior scalene. The main mechanism of injury to the lower brachial plexus is hyper-abduction traction, and depending on the intensity, it will lead to signs and symptoms consistent with a neurological insult.
The most common aetiology resulting in Klumpke palsy is a hyper-abduction trauma to the arm that has enough intensity to traction the lower brachial plexus. Trauma during birth can cause brachial plexus injuries, but again hyper-abduction and traction forces to the upper extremity are usually present.
The history presented by the patient usually depicts a long axis hyper-abduction traction injury with high amplitude and velocity. The typical patient presentation is a decrease of sensation along the medial aspect of the distal upper extremity along the C8 and T1 dermatome. The patient might also present myotome findings that can range from decreasing muscular strength to muscular atrophy and positional deformity. For example, if the neurological damage has led to muscular atrophy and tightening, the patient may present with a claw hand. This deformity presents a finger and wrist flexion. The patient may also describe the severe pain that starts at the neck and travels down the medial portion of the arm. One other sign of a lower brachial plexus injury is Horner syndrome; because of its approximation to the T1 nerve root, it may damage the cephalic sympathetic chain. If this happens, the patient will develop ipsilateral ptosis, anhidrosis, and miosis.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 183
Incorrect
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Which of the following is first-line for management of status epilepticus:
Your Answer:
Correct Answer: Intravenous lorazepam
Explanation:First-line treatment is with intravenous lorazepam if available. Intravenous diazepam is effective but it carries a high risk of thrombophlebitis so should only be used if intravenous lorazepam is not immediately available. Absorption of diazepam from intramuscular injection or from suppositories is too slow for treatment of status epilepticus. When facilities for resuscitation are not immediately available or if unable to secure immediate intravenous access, diazepam can be administered as a rectal solution or midazolam oromucosal solution can be given into the buccal cavity.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 184
Incorrect
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A 44 year old woman is brought to ED having fallen down the stairs and injured her right arm. On examination she is unable to abduct her arm normally, and has weakness of lateral rotation. She has sensory loss over the lateral aspect of her upper arm. Which of the following injuries is most likely to produce this pattern of injury:
Your Answer:
Correct Answer: Surgical neck of humerus fracture
Explanation:Damage to the axillary nerve will result in loss of abduction past about 15 degrees and weakness of lateral rotation due to paralysis of the deltoid and teres minor and loss of sensation over the regimental badge area on the upper lateral arm. The axillary nerve is most likely injured in fracture of the surgical neck of the humerus due to its course where it winds around this region together with the posterior humeral circumflex vessels.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 185
Incorrect
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A 26-year-old man is involved in a motorcycle accident that results in an open fracture of his tibia and fibula. The nerve that innervates peroneus tertius is damaged as a consequence of his injuries.
Peroneus tertius receives its innervation from which of the following nerves? Select ONE answer only.Your Answer:
Correct Answer: Deep peroneal nerve
Explanation:Peroneus brevis is innervated by the superficial peroneal nerve.
Peroneus longus is innervated by the superficial peroneal nerve.
Peroneus tertius is innervated by the deep peroneal nerve. -
This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 186
Incorrect
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Injury to which nerve can lead to weakness or paralysis of the brachialis muscle?
Your Answer:
Correct Answer: The musculocutaneous nerve
Explanation:The brachialis muscle is a prime flexor of the forearm at the elbow joint. It is fusiform in shape and located in the anterior (flexor) compartment of the arm, deep to the biceps brachii. The brachialis is a broad muscle, with its broadest part located in the middle rather than at either of its extremities. It is sometimes divided into two parts, and may fuse with the fibres of the biceps brachii, coracobrachialis, or pronator teres muscles. It also functions to form part of the floor of the cubital fossa.
The brachialis is primarily supplied by the musculocutaneous nerve (C5, C6). In addition, a small lateral portion of the muscle is innervated by the radial nerve (C7).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 187
Incorrect
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The lymph drainage of the anal canal above the pectinate line is initially to the:
Your Answer:
Correct Answer: Internal iliac nodes
Explanation:Above the pectinate line, the anal canal drains to the internal iliac lymph nodes which subsequently drain to the lumbar (para-aortic) nodes.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 188
Incorrect
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Which lobe of the prostate gland is most commonly affected in prostatic carcinoma?
Your Answer:
Correct Answer: Posterior
Explanation:The periurethral portion of the prostate gland increases in size during puberty and after the age of 55 years due to the growth of non-malignant cells in the transition zone of the prostate that surrounds the urethra. Most cancers develop in the posterior lobe, and cancers in this location may be palpated during a digital rectal examination (DRE).
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 189
Incorrect
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Through which of the following anatomical structures does an indirect inguinal hernia pass?
Your Answer:
Correct Answer: External oblique
Explanation:Inguinal hernias are subdivided into direct and indirect.
An indirect hernia occurs when abdominal contents protrude through the internal inguinal ring and into the inguinal canal. This occurs lateral to the inferior epigastric vessels. The hernia contents may extend into the scrotum.
A direct inguinal hernia is protrusion of abdominal contents through the transversalis fascia within Hesselbach’s triangle. The borders of Hesselbach’s triangle are the inferior epigastric vessels superolaterally, the rectus sheath medially, and inguinal ligament inferiorly.
The deep (internal) inguinal ring is located above and halfway between the pubic tubercle and the anterior superior iliac spine. This serves as the entrance to the inguinal canal. The superficial (external) inguinal ring lies immediately above and medial to the pubic tubercle. This triangular opening is a defect in the external oblique aponeurosis, and forms the exit of the inguinal canal.
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 190
Incorrect
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Which of the following accurately describes the extensor pollicis brevis muscle?
Your Answer:
Correct Answer: It lies on the medial side of abductor pollicis longus
Explanation:Extensor pollicis brevis is a short and slender muscle located in the posterior compartment of the forearm, extending from the posterior surface of radius to the proximal phalanx of thumb. It is one of the deep extensors of the forearm, together with supinator, abductor pollicis longus, extensor pollicis longus and extensor indicis muscles.
Extensor pollicis brevis is a deep extensor of the thumb that lies deep to extensor digitorum muscle. It sits directly medial to abductor pollicis longus and posterolateral to extensor pollicis longus muscle. Just above the wrist, extensor pollicis brevis obliquely crosses the tendons of extensor carpi radialis brevis and extensor carpi radialis longus muscles.
Extensor pollicis brevis is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).
Extensor pollicis brevis receives its blood supply by posterior interosseous artery and perforating branches from the anterior interosseous artery, which are the branches of common interosseous artery. The common interosseous artery arises immediately below the tuberosity of radius from the ulnar artery.
Together with extensor pollicis longus, extensor pollicis brevis is in charge of extension of the thumb in the first metacarpophalangeal joint. It also extends the thumb in the carpometacarpal joint of the thumb. This movement is important in the anatomy of the grip, as it enables letting go of an object. As it crosses the wrist, extensor pollicis brevis also participates in the extension and abduction of this joint.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 191
Incorrect
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A 70-year-old man presents with right-sided hemiplegia and loss of joint position sense, vibratory sense, and discriminatory touch. Upon further physical examination, it was observed that her tongue deviates to the left-hand side. An MRI and CT scan was ordered and results showed that he was suffering a left-sided stroke.
Branches of which of the following arteries are most likely implicated in the case?Your Answer:
Correct Answer: Anterior spinal artery
Explanation:Medial medullary syndrome is a form of stroke that affects the medial medulla of the brain. It is caused by a lesion in the medial part of the medulla, which is due to an infraction of vertebral arteries and/or paramedian branches of the anterior spinal artery.
It is characterized by contralateral paralysis of the upper and lower limb of the body, a contralateral decrease in proprioception, vibration, and/or fine touch sensation, paresthesias or less commonly dysesthesias in the contralateral trunk and lower limb, and loss of position and vibration sense with proprioceptive dysfunction. Ipsilateral deviation of the tongue due to ipsilateral hypoglossal nerve damage can also be seen.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 192
Incorrect
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A man presents to the emergency department with an injury that has damaged the opponens pollicis muscle.
Which of the following statements regarding the opponens pollicis muscle is considered correct?Your Answer:
Correct Answer: It flexes the first metacarpal bone at the carpometacarpal joint
Explanation:Opponens pollicis is a muscle of thenar eminence, it is triangular in shape and lies deep to flexor pollicis brevis and abductor pollicis brevis. It originates from the flexor retinaculum, tubercles of scaphoid and trapezium, abductor pollicis longus tendon.
Its insertion is in the radial side of the base of proximal phalanx of thumb. It is supplied by the median nerve (C8, T1). It receives blood supply from superficial arch.
It flexes the metacarpal bone medially across the palm, also rotating it medially, causing opposition, the palmar aspect of the terminal segment of thumb contacts the flexor aspects of any other digit.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 193
Incorrect
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Which of the following clinical features is NOT typical of a facial nerve palsy:
Your Answer:
Correct Answer: Inability to raise the eyelid
Explanation:Facial nerve palsy can result in inability to close the eye due to paralysis of the orbicularis oculi muscle. Elevation of the eyelid in eye opening is a function of the levator palpebrae superioris muscle and the superior tarsal muscle, innervated by the oculomotor nerve and the sympathetic chain respectively.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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Question 194
Incorrect
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Your consultant requests that you do a lumbar puncture on a patient who is suspected of having meningitis. This patient, a 15-year-old female, presented to the emergency department with a fever, headache, and neck stiffness. Where should you aspirate a sample of CSF?
Your Answer:
Correct Answer: Subarachnoid space
Explanation:A lumbar puncture, also known as a spinal tap, is a procedure that involves inserting a needle into the lower back’s lumbar region.
A needle is inserted into the space between the arachnoid mater and the pia mater, also known as the subarachnoid space, to remove a sample of cerebrospinal fluid.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 195
Incorrect
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Which of the following statements is correct regarding paracetamol?
Your Answer:
Correct Answer: Liver damage peaks 3 to 4 days after paracetamol ingestion.
Explanation:The maximum daily dose of paracetamol in an adult is 4 grams. Doses greater than this can lead to hepatotoxicity and, less frequently, acute kidney injury. Early symptoms of paracetamol toxicity include nausea, vomiting, and abdominal pain, and usually settle within 24 hours. Symptoms of liver damage include right subcostal pain and tenderness, and this peaks 3 to 4 days after paracetamol ingestion. Other signs of hepatic toxicity include encephalopathy, bleeding, hypoglycaemia, and cerebral oedema.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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Question 196
Incorrect
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The most important nerve for plantar flexion of the foot at the ankle joint is:
Your Answer:
Correct Answer: Tibial nerve
Explanation:Muscles of the posterior compartment of the leg, innervated by the tibial nerve, perform plantar flexion of the foot at the ankle joint. The fibularis longus (innervated by the superficial fibular nerve) assists in plantar flexion but is not the most important.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 197
Incorrect
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A 30-year-old man presents with piriformis syndrome pain, tingling, and numbness in her buttocks. He noted that the pain gets worse upon sitting down. He was seen by a physiotherapist and a diagnosis of piriformis syndrome was made.
Which of the following nerves becomes irritated in piriformis syndrome?Your Answer:
Correct Answer: Sciatic nerve
Explanation:Piriformis syndrome is a clinical condition of sciatic nerve entrapment at the level of the ischial tuberosity. While there are multiple factors potentially contributing to piriformis syndrome, the clinical presentation is fairly consistent, with patients often reporting pain in the gluteal/buttock region that may shoot, burn or ache down the back of the leg (i.e. sciatic-like pain). In addition, numbness in the buttocks and tingling sensations along the distribution of the sciatic nerve is not uncommon.
The sciatic nerve runs just adjacent to the piriformis muscle, which functions as an external rotator of the hip. Hence, whenever the piriformis muscle is irritated or inflamed, it also affects the sciatic nerve, which then results in sciatica-like pain.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 198
Incorrect
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A patient suffers a stab wound to the neck. The entry point of the blade is situated within the anterior triangle of the neck.
Which of the following muscles is most likely to be involved? Select ONE answer only.Your Answer:
Correct Answer: Sternothyroid
Explanation:The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:
Muscles: thyrohyoid, sternothyroid, sternohyoid muscles
Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland
Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries
Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins
Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerveThe posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.
Contents:
Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes
Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus -
This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 199
Incorrect
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A 64-year-old woman had a humerus midshaft fracture due to tripping on a curb and falling on her left arm. She might also have damaged which of the following structures?
Your Answer:
Correct Answer: Radial nerve and deep brachial artery
Explanation:The radial nerve and brachial artery are most likely to be damaged in humerus fractures. They are tethered together to the bone and cannot withstand the forces applied to it as a result of the displacement.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 200
Incorrect
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Which of the following is NOT a contraindication to treatment with aspirin at analgesic doses:
Your Answer:
Correct Answer: Myasthenia gravis
Explanation:Aspirin (at analgesic doses) is contraindicated in:
People with a history of true hypersensitivity to aspirin or salicylates (symptoms of hypersensitivity to aspirin or salicylates include bronchospasm, urticaria, angioedema, and vasomotor rhinitis)
People with active or previous peptic ulceration
People with haemophilia or another bleeding disorder
Children younger than 16 years of age (risk of Reye’s syndrome)
People with severe cardiac failure
People with severe hepatic impairment
People with severe renal impairmentN.B. Owing to an association with Reye’s syndrome, aspirin-containing preparations should not be given to children under 16 years, unless specifically indicated, e.g. for Kawasaki disease.
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This question is part of the following fields:
- Central Nervous System
- Pharmacology
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SESSION STATS - PERFORMANCE PER SPECIALTY
