1- Upper limb MSQs Only

Question 1

(1-601) A 10 year old boy is admitted to the emergency department following a fall. On examination, there is deformity and swelling of the forearm. The ability to flex the fingers of the affected limb is impaired. However, there is no sensory impairment. Imaging confirms a displaced forearm fracture. Which of the nerves listed below is likely to have been affected?

Answer 1

Anterior interosseous nerve

Forearm fractures may be complicated by neurovascular compromise. The anterior interosseous nerve may be affected. It has no sensory supply so the defect is motor alone.

Question 2

(2 - 601)
Which of the following nerves supplies the skin on the palmar aspect of the thumb?

Answer 2

Median

The median nerve supplies cutaneous sensation to this region.

Question 3

( 7 of 601)

A 63 year old lady is undergoing an axillary sentinel lymph node biopsy as part of her breast cancer treatment. Which of the structures listed below is most likely to be encountered?

Answer 3

Intercostobrachial nerve

A particularly careless surgeon could encounter all of these. However, during a routine level 1 axillary exploration which is where the majority of sentinel nodes will be located, the nerves most commonly encountered are the Intercostobrachial nerves.

Question 4

(10 of 601)
A 35 year old farm labourer injures the posterior aspect of his hand with a mechanical scythe. He severs some of his extensor tendons in this injury. How many tunnels lie in the extensor retinaculum that transmit the tendons of the extensor muscles?

Answer 4

Six

There are six tunnels, each lined by its own synovial sheath.

Question 5

(Question 12 of 601)

Which of the muscles listed below is not innervated by the median nerve?

Answer 5

Adductor pollicis

Adductor pollicis is innervated by the ulnar nerve.
Medial two lumbricals innervated by the ulnar nerve

Question 6

( 14 of 601 )
A 23 year old man is involved in a fight outside a nightclub and sustains a laceration to his right arm. On examination, he has lost extension of the fingers in his right hand. Which of the nerves listed below is most likely to have been divided?

Answer 6

Radial

The radial nerve supplies the extensor muscle group

Question 7

( 17 of 601 )
An injured axillary artery is ligated between the thyrocervical trunk of the subclavian and subscapular artery. Subsequent collateral circulation is likely to result in reversal of blood flow in which of the vessels listed below?

Answer 7

Transverse cervical artery

It is asking about the branches of the axillary artery and knowledge of the fact that there is an extensive collateral network around the shoulder joint

Question 8

(23 of 601)
A 43 year old typist presents with pain at the dorsal aspect of the upper part of her forearm. She also complains of weakness when extending her fingers. On examination triceps and supinator are both functioning normally. There is weakness of most of the extensor muscles. However, there is no sensory deficit. Which of the following nerves has been affected?

Answer 8

Posterior interosseous

Question 9

(29 of 601)
A 23 year old man falls and slips at a nightclub. A shard of glass penetrates the skin at the level of the medial epicondyle, which of the following sequelae is least likely to occur?

Answer 9

Claw like appearance of the hand

Question 10

(31 of 601)
A 43 year old man is stabbed outside a nightclub. He suffers a transection of his median nerve just as it leaves the brachial plexus. Which of the following features is least likely to ensue?

Answer 10

Complete loss of wrist flexion

Question 11

(33 of 601)
Which of the structures listed below articulates with the head of the radius superiorly?

Answer 11

Capitulum

The head of the radius articulates with the capitulum of the humerus.

Question 12

39 of 601
At the level of the wrist joint, which of the statements below best describes the relationship of the ulnar artery to the ulnar nerve?

Answer 12

It lies on its radial side

Question 13

40 of 601
Which of the following anatomical structures lies within the spiral groove of the humerus?

Answer 13

Radial nerve

The radial nerve lies in this groove and may be compromised by fractures involving the shaft.

Question 14

41 of 601
A 24 year old man falls and sustains a fracture through his scaphoid bone. From which of the following areas does the scaphold derive the majority of its blood supply?

Answer 14

From the distal end

The blood supply to the scaphoid enters from a small non articular surface near its distal end. Transverse fractures through the scaphoid therefore carry a risk of non union

Question 15

43 of 601
A patient sustains damage to the median nerve during a carpal tunnel release. Which of the following muscles will be affected?

Answer 15

Abductor pollicis brevis

Of the muscles listed, only the abductor pollicis brevis is innervated by the median. In questions like this one, ensure you don’t become confused between adductor and abductor.

Question 16

52 of 601
Which of the nerves listed below is directly responsible for the innervation of the lateral aspect of flexor digitorum profundus?

Answer 16

Anterior interosseous nerve

The anterior interosseous nerve is a branch of the median nerve and is responsible for innervation of the lateral aspect of the flexor digitorum profundus.

Question 17

55 of 601

Which of the structures listed below are most closely related to the axillary nerve within the quadrangular space?

Answer 17

Posterior circumflex humeral vessels

The posterior circumflex humeral vessels which are branches of the axillary artery are related to the axillary nerve within the quadrangular space

Question 18

62 of 601
Which muscle initiates abduction of the shoulder?

Answer 18

Supraspinatus

The intermediate portion of the deltoid muscle is the chief abductor of the humerus. it can only do this after the movement has been initiated by supraspinatus. Damage to the te supraspinatus is a common form of rotator cuff disease.

Question 19

69 of 601
The first root of the brachial plexus commonly arises at which of the following levels?

Answer 19

C5

It begins at C5 and has 5 roots. It ends with a total of 15 nerves of these 5 are the main nerves to the upper limb (axillary, radial, ulnar, musculocutaneous and median)

Question 20

72 of 601
When the brachial plexus is injured in the axilla as a result of a crutch palsy, which of the nerves listed is most commonly affected?

Answer 20

Radial nerve

The radial nerve is most commonly injured and results in a wrist drop. The ulnar nerve arises from the medial cord and is rarely affected as a result of this injury mechanism.

Question 21

81 of 601

A 56 year old man requires long term parenteral nutrition and the decision is made to insert a PICC line for long term venous access. This is inserted into the basilic vein at the region of the elbow. As the catheter is advanced, into which venous structure is the tip of the catheter most likely to pass from the basilic vein?

Answer 21

Axillary vein

The basilic vein drains into the axillary vein and although PICC lines may end up in a variety of fascinating locations the axillary vein is usually the commonest site following from the basilic. The posterior circumflex humeral vein is encountered prios to the axillary vein. However, a PICC line is unlikely to enter this structure because of its angle of entry into the basilic vein

Question 22

83 of 601
An 8 year old boy falls onto an outstretched hand and sustains a supracondylar fracture. In addition to a weak radial pulse the child is noted to have loss of pronation of the affected hand. Which nerve is compromised?

Answer 22

Median

This is a common injury in children. In this case the angulation and displacement have resulted in median nerve injury

Question 23

84 of 601
A 40 year old lady trips and falls through a glass door and sustains a severe laceration to her left arm. Amongst her injuries it is noticed that she has lost the ability to adduct the fingers of her left hand. Injury to which of the following nerves is most likely to account for her examination findings?

Answer 23

Ulnar

The interossei are supplied by the ulnar nerve

Question 24

98 of 601
A 28 year old rugby player injures his right humerus and on examination is noted to have a minor sensory deficit overlying the point of deltoid insertion into the humerus. Which of the nerves listed below is most likely to have been affected?

Answer 24

Axillary

Question 25

104 of 601 A 21 year old man is stabbed in the antecubital fossa. A decision is made to surgically explore the wound. At operation the surgeon dissects down onto the brachial artery. A nerve is identified medially, which nerve is it likely to be?

Answer 25

Median

Question 26

Question 109 of 601 Which of the following muscles does not attach to the radius?

Answer 26

Brachialis The brachialis muscle inserts into the ulna. The other muscles are all inserted onto the radius.

Question 27

110 of 601 A 25 year old man is stabbed in the upper arm. The brachial artery is lacerated at the level of the proximal humerus, and is being repaired. A nerve lying immediately lateral to the brachial artery is also lacerated. Which of the following is the nerve most likely to be?

Answer 27

Median nerve The brachial artery begins at the lower border of teres major and terminates in the cubital fossa by branching into the radial and ulnar arteries in the upper arm the median gerve lies closest to it in the lateral position. In the cubital fossa it lies medial to it

Question 28

111 of 601 What is the course of the median nerve relative to the brachial artery in the upper arm?

Answer 28

Lateral to anterior to medial Relations of median nerve to the brachial artery Lateral >Anterior > Medial. The median nerve descends lateral to the brachial artery, it usually passes anterior to the artery to lie on its medial side it passes deep to the bicipital aponeurosis and the median cubital vein at the elbow. It enters the forearm between the two heads of the pronator teres muscle.

Question 29

124 of 601 The following statements relating to the musculocutaneous nerve are true except?

Answer 29

If damaged, then extension of the elbow joint will be impaired It supplies biceps, brachialis and coracobrachialis. if damaged then elbow flexion will be impaired

Question 30

136 of 601 Which of the muscles listed below is attached to the anterior aspect of the fibrous capsule that encases the elbow joint?

Answer 30

Brachialis The brachialis inserts some of its fibres into the fibrous joint of the elbow capsule and when contracts, it helps to flex the joint

Question 31

137 of 601 A 32 year old rugby player is hit hard on the shoulder during a rough tackle. Clinically, his arm is hanging loose on the side. It is pronated and medially rotated. What structure is most likely to have been compromised?

Answer 31

Brachial trunks C5-6 The patient has an Erb's palsy involving brachial trunks C5-6

Question 31

139 of 601 A 73 year old man undergoes an excision biopsy of a lymph node that is closely applied to sternocleidomastoid. This muscle is mobilized and a nerve that is present is damaged. Which muscle below is most likely to be affected?

Answer 31

Trapezius The accessory nerve has a number of lymph nodes applied to it near the sternocleidomastoid muscle. It is particularly at risk if SCM is mobilized. Injured, the trapezius muscle and SCM will be paralysed.

Question 32

140 of 601 A 35 year tennis player attends reporting tingling down his arm. He says that his 'funny bone' was hit very hard by a tennis ball. There is weakness of abduction and adduction of his extended fingers. Which nerve has been affected?

Answer 32

Ulnar The ulnar nerve arises from the medial cord of the brachial plexus (C8, T1 and contribution from C7). The nerve descends between the axillary artery and vein, posterior to the cutaneous nerve of the forearm and then lies anterior to triceps on the medial side of the brachial artery. In the distal half of the arm it passes through the medial intermuscular septum, and continues between this structure and the medial head of triceps to enter the forearm between the medial epicondyle of the humerus and the olecranon. It may be injured at this site in this scenario

Question 33

154 of 601 A 22 year old falls over and lands on a shard of glass. It penetrates the palmar aspect of his hand, immediately lateral to the pisiform bone. Which of the following structures is most likely to be injured?

Answer 33

Ulnar artery The ulnar nerve and artery are at most immediate risk in this injury

Question 34

159 of 601 A motorcyclist is involved in a road traffic accident. He suffers a complex humeral shaft fracture which is plated. Post operatively he complains of an inability to extend his fingers. Which of the following structures is most likely to have been injured?

Answer 34

Radial nerve The racial nerve is responsible for innervation of the extensor compartment of the forarm

Question 35

161 of 601 A 48 year old lady is undergoing an axillary node clearance for breast cancer. Which of the structures listed below are most likely to be encountered during the axillary dissection?

Answer 35

Thoracodorsal trunk Beware of damaging the thoracodorsal trunk if a latissimus dorsi flap reconstruction is planned. The thoracodorsal trunk runs through the nodes in the axilla. If injured it may compromise the function and blood supply to latissimus dorsi, which is significant if it is to be used as a flap for a reconstructive procedure

Question 36

162 of 601 A 53 year old lady is recovering following a difficult mastectomy and axillary nodal clearance for carcinoma of the breast. She complains of shoulder pain and on examination has obvious winging of the scapula. Loss of innervation to which of the following is the most likely underlying cause?

Answer 36

Serratus anterior Winging of the scapula is most commonly the result of long thoracic nerve injury or dysfunction latrogenic damage during the course of the difficult axillary dissection is the most likely cause in this scenario. Damage to the rhomboids may produce winging of the scapula but would be rare in the scenario given.

Question 36

163 of 601 How many phalanges are there in the hand?

Answer 36

14 Each digit has 3 phalanges, the thumb has two the total is therefore 14

Question 36

183 of 601 A 23 year old climber falls and fractures his humerus. The surgeons decide upon a posterior approach to the middle third of the bone. Which of the following nerves is at greatest risk in this approach?

Answer 36

Radial The radial nerve wraps around the humerus and may be injured during a posterior approach. An IM nail may be preferred as it avoids the complex dissection needed for direct bone exposure.

Question 37

187 of 601 What is the largest branch of the brachial artery?

Answer 37

Profunda brachii artery The profunda brachii artery is the largest branch and then continues in the radial groove of the humerus.

Question 38

194 of 601 Which of the following nerves is responsible for innervation of the triceps muscle?

Answer 38

Radial To remember nerve roots and their reflexes 1-2 Ankle (S1-S2) 3-4 Knee (L3-L4) 5-6 Biceps (C5-C6) 7-8 Triceps (C7-C8) The radial nerve innervates all three heads of triceps, with a separate branch to each head.

Question 39

203 of 601 A patient presents to the clinic following a surgical procedure. She complains that she is unable to shrug her shoulder. What is the most likely underlying nerve injury?

Answer 39

accessory nerve The accessory nerve may be injured in operations in the posterior triangle. Injury will affect trapezius.

Question 40

205 of 601 The cords of the brachial plexus are most closely related to which of the following vessels?

Answer 40

Axillary artery The trunks are related to the subclavian artery superiorly. The cords of the plexus surround the axillary artery, they are named according to their positions relative to this structure

Question 41

213 of 601 A 23 year old rugby player sustains a Smiths Fracture. On examination, opposition of the thumb is markedly weakened. Which of the following nerves is least likely to be working normally?

Answer 41

Median This high velocity injury can often produce significant angulation and displacement. Both of these may impair the function of the median nerve with loss of function of the muscles of the thenar eminence.

Question 41

223 of 601 A 73 year old lady suffers a fracture at the surgical neck of the humerus. The decision is made to operate. There are difficulties in reducing the fracture and a vessel lying posterior to the surgical neck is injured. Which of the following is this vessel most likely to be?

Answer 41

Posterior circumflex humeral artery The circumflex humeral arteries lie at the surgical neck and is this scenario the posterior circumflex is likely to be injured. The thoracoacromial and transverse scapular arteries lie more superomedially. The posterior circumflex humeral artery is a branch of the axillary artery

Question 41

212 of 601 Which structure separates the cephalic vein and the brachial artery in the antecubital fossa?

Answer 41

Biceps muscle

Question 42

218 of 601 Which of the following muscles inserts onto the lesser tuberostiy of the the humerus?

Answer 42

Supscapularis With the exception of subscapularis which inserts into the lesser tuberosity, the muscles of the rotator cuff insert into the greater tuberosity

Question 43

233 of 601 Which of the following upper limb muscles is not innervated by the radial nerve?

Answer 43

Abductor digiti minimi Mnemonic for radial nerve muscles: BEST Brachioradialis Extensors Supinator Triceps Abductor digiti minimi is innervated by the ulnar nerve

Question 44

237 of 601 Which nerve supplies the skin at the medial aspect of the palm?

Answer 44

Ulnar

Question 45

238 of 601 Which muscle is responsible for causing flexion of the distal interphalangeal joint of the ring finger?

Answer 45

Flexor digitorum profundus Flexor digitorum superficialis and flexor digitorum profundus are responsible for causing flexion. The superficialis tendons insert on the bases of the middle phalanges; the profundus tendons insert on the bases of the distal phalanges. Both tendons fiex the wrist, MCP and PIP joints; however, only the profundus tendons flex the DIP joints

Question 46

240 of 601 A 32 year old lady complains of carpal tunnel syndrome. The carpal tunnel is explored surgically. Which of the following structures will lie in closest proximity to the hamate bone within the carpal tunnel?

Answer 46

The tendons of flexor digitorum profundus The carpal tunnel contains nine flexor tendons: Flexor digitorum profundus Flexor digitorum superficialis Flexor pollicis longus. The tendon of flexor digitorum profundus lies deepest in the tunnel and will thus lie nearest to the hamate bone

Question 47

242 of 601 Which nerve supplies the interossei of the fourth finger?

Answer 47

Deep Ulnar Mnemonic PAD and DAB Palmer interossei ADduct Dorsal interossei ABduct

Question 48

251 of 601 A 45 year man presents with hand weakness. He is given a piece of paper to hold between his thumb and index finger. When the paper is pulled, the patient has difficulty maintaining a grip. Grip pressure is maintained by flexing the thumb at the interphalangeal joint. What is the most likely nerve lesion?

Answer 48

Deep branch of ulnar nerve This is a description of Froment's sign, which tests for ulnar nerve palsy. It mainly tests for the function of adductor pollicis. This is supplied by the deep branch of the ulnar nerve. Remember the anterior interosseous branch (of the median nerve), which innervates the flexor pollicis longus (hence causing flexion of the thumb IP joint), branches off more proximally to the wrist.

Question 49

253 of 601 A 22 year old man is involved in a fight and sustains a stab wound in his upper forearm. On examination there is a small, but deep laceration. There is an obvious loss of pincer movement involving the thumb and index finger with minimal loss of sensation. The most likely nerve injury is to the:

Answer 49

Anterior interosseous nerve The anterior interosseous nerve is a motor branch of the median nerve just below the elbow. When damaged it classically causes: - Pain in the forearm - Loss of pincer movement of the thumb and index finger (innervates the long flexor muscles of flexor pollicis longus & flexor digitorum profundus of the index and middle finger) - Minimal loss of sensation due to lack of a cutaneous branch

Question 50

259 of 601 A 32 year old attends neurology clinic complaining of tingling in his hand. He has radial deviation of his wrist and there is mild clawing of his fingers, with the 4th and 5th digits being relatively spared. What is the most likely lesion?

Answer 50

Ulnar nerve damage at the elbow The ulnar paradox- the higher the lesion, the less the clawing of the fingers seen clinically. At the elbow the ulnar nerve lesion affects the flexor carpi ulnaris and flexor digitorum profundus.

Question 51

273 of 601 A man has an incision sited that runs 8cm from the deltopectoral groove to the midline. Which of the following is not at risk of injury?

Answer 51

‏Cephalic vein ‏Axillary artery ‏ Pectoralis major ‏ Trunk of the brachial plexus الصح Shoulder joint capsule This region will typically lie medial to the joint capsule. The diagram below illustrates the plane that this would transect and as it can be appreciated the other structures are all at risk of injury

Question 51

269 of 601 A 22 year old man is involved in a fight. He sustains a laceration to the posterior aspect of his wrist. In the emergency department the wound is explored and the laceration is found to be transversely orientated and overlies the region of the extensor retinaculum, which is intact. Which of the following structures is least likely to be injured in this scenario?

Answer 51

Tendon of extensor indicis The extensor retinaculum attaches to the radius proximal to the styloid, thereafter it runs obliquely and distally to wind around the ulnar styloid (but does not attach to it). The extensor tendons lie deep to the extensor retinaculum and would therefore be less susceptible to injury than the superficial structures

Question 52

279 of 601 Which of the following nerves does not contribute to the innervation of the elbow joint?

Answer 52

Posterior interosseous The posterior interosseous nerve does not innervate the elbow joint.

Question 53

281 of 601 A 23 year old man is injured during a game of rugby. He suffers a fracture of the distal third of his clavicle, it is a compound fracture and there is evidence of arterial haemorrhage. Which of the following vessels is most likely to be encountered first during subsequent surgical exploration?

Answer 53

Thoracoacromial artery The thoracoacromial artery arises from the second part of the axillary artery. It is a short, wide trunk, which pierces the clavipectoral fascia, and ends, deep to pectoralis major by dividing into four branches

Question 54

287 of 601 A 38 year old man falls onto an outstretched hand. Following the accident he is examined in the emergency department. On palpating his anatomical snuffbox there is tenderness noted in the base. What is the most likely injury in this scenario?

Answer 54

Scaphoid fracture A fall onto an outstretched hand is a common mechanism of injury for a scaphoid fracture. This should be suspected clinically if there is tenderness in the base of the anatomical snuffbox. A tendan rupture would not result in bony tenderness.

Question 54

289 of 601 Which of the following structures passes through the quadrangular space near the humeral head?

Answer 54

Axillary nerve The quadrangular space is bordered by the humerus laterally, subscapularis superiorly, teres major inferiorly and the long head of triceps medially. It lies lateral to the triangular space. It transmits the axillary nerve and posterior circumflex humeral artery.

Question 55

292 of 601 What is the first branch of the axillary artery?

Answer 55

Superior thoracic artery The superior thoracic artery is the first branch of the axillary artery arises from the first part Two branches arise from the second part, thoraco acromial and lateral thoracic Three branches from the third part, subscapular artery, anterior and postenor circumfiex humeral arteries

Question 56

294 of 601 Which of the following structures separates the ulnar artery from the median nerve?

Answer 56

Pronator teres It lies deep to pronator teres and this separates it from the median nerve.

Question 57

296 of 601 A 32 year old motorcyclist is involved in a road traffic accident. His humerus is fractured and severely displaced. At the time of surgical repair the surgeon notes that the radial nerve has been injured. Which of the following muscles is least likely to be affected by an injury at this site?

Answer 57

Extensor carpi radialis brevis Brachioradialis Abductor pollicis longus Extensor pollicis brevis None of the above الصح Muscles supplied by the radial nerve BEST - Brachioradialis - Extensors - Supinator - Triceps The radial nerve supplies the extensor muscles, abductor pollicis longus and extensor pollicis brevis (the latter two being innervated by the posterior intesseous branch of the radial nerve)

Question 58

298 of 601 Which muscle is responsible for causing flexion of the interphalangeal joint of the thumb?

Answer 58

Flexor pollicis longus There are 8 muscles 1. Two flexors (flexor pollicis brevis and flexor pollicis longus) 2. Two extensors (extensor pollicis brevis and longus) 3. Two abductors (abductor pollicis brevis and longus) 4. One adductor (adductor pollicis) 5. One muscle that opposes the thumb by rotating the CMC joint (opponens pollicis). Flexor and extensor longus insert on the distal phalanx moving both the MCP and IP joints

Question 59

304 of 601 An 18 year old man is stabbed in the axilla during a fight. His axillary artery is lacerated and repaired. However, the surgeon neglects to repair an associated injury to the upper trunk of the brachial plexus. Which of the following muscles is least likely to demonstrate impaired function as a result?

Answer 59

Palmar interossei The palmar interossel are supplied by the ulnar nerve. Which lies inferiorly and is therefore less likely to be injured

Question 60

305 of 601 A 23 year old man is involved in a fight, during the dispute he sustains a laceration to the posterior aspect of his right arm, approximately 2cm proximal to the olecranon process. On assessment in the emergency department he is unable to extend his elbow joint. Which of the following tendons is most likely to have been cut?

Answer 60

Triceps The triceps muscle extends the elbow joint. The other muscles listed all produce flexion of the elbow joint.

Question 61

311 of 601 Which of the following is not an intrinsic muscle of the hand?

Answer 61

Palmaris longus Mnemonic for intrinsic hand muscles 'A OF A OF A A bductor pollicis brevis O pponens pollicis Flexor pollicis brevis A dductor pollicis (thenar muscles) O pponens digiti minimi Flexor digiti minimi brevis A bductor digiti minimi (hypothenar muscles) Palmaris longus originates in the forearm

Question 62

314 of 601 A 28 year old man lacerates the posterolateral aspect of his wrist with a knife in an attempted suicide. On arrival in the emergency department the wound is inspected and found to be located over the lateral aspect of the extensor retinaculum (which is intact). Which of the following structures is at greatest risk of injury?

Answer 62

Superficial branch of the radial nerve The superficial branch of the radial nerve passes superior to the extensor retinaculum in the position of this laceration and is at greatest risk of injury. The dorsal branch of the ulnar nerve and artery also pass superior to the extensor retinaculum n but are located medially.

Question 63

317 of 601 Transection of the radial nerve at the level of the axilla will result in all of the following except:

Answer 63

elbow extension. Loss of extension of the interphalangeal joints. الصح Loss of metacarpophalangeal extension. Loss of triceps reflex. Loss of sensation overlying the first dorsal interosseous. ‏These may still extend by virtue of retained lumbrical muscle function

Question 64

324 of 601 Which of the following muscles does not adduct the shoulder?

Answer 64

Teres major Pectoralis major Coracobrachialis Supraspinatus الصح Latissimus dorsi Supraspinatus is an abductor of the shoulder

Question 65

332 of 601 Which of the following structures is not closely related to the brachial artery?

Answer 65

Ulnar nerve Median nerve Cephalic vein الصح Long head of triceps Median cubital vein The cephalic vein lies superficially and on the contralateral side of the arm to the brachial artery.

Question 66

333 of 601 Which ligament keeps the head of the radius connected to the radial notch of the ulna?

Answer 66

Annular (orbicular) ligament The annular ligament connects the radial head to the radial notch of the ulna.

Question 67

334 of 601 A 38 year old man presents to the clinic with shoulder weakness. On examination he has an inability to initiate shoulder abduction. Which of the nerves listed below is least likely to be functioning normally?

Answer 67

Suprascapular nerve

Question 68

338 of 601 Which of the following vessels provides the greatest contribution to the arterial supply of the breast?

Answer 68

Internal mammary artery 60% of the arterial supply to the breast is derived from the internal mammary arteryز The external mammary and lateral thoracic arteries also make a significant (but lesser) contribution. This is of importance clinically in performing reduction mammoplasty procedures

Question 69

345 of 601 A baby is found to have a Klumpke's palsy post delivery. Which of the following is most likely to be present?

Answer 69

Loss of flexors of the wrist Features of Klumpkes Paralysis : - Claw band (MCP Joints extended and IP joints flexed) - Loss of sensation over medial aspect of forearm and hand - Horner's syndrome - Loss of flexors of the wrist A C8 T1 root lesion is called Klumpke's paralysis an is caused by delivery with the arm extended.

Question 70

353 of 601 Through which of the structures listed below does the axillary nerve pass?

Answer 70

Quadrangular space الصح Triangular space Subclavicular space Sub pectoral space Intercostal space Axillary nerve passes through the quadrangular

Question 71

Question 354 of 601 With respect to the basilic vein, which statement is false?

Answer 71

- Its deep anatomical location makes it unsuitable for use as an arteriovenous access site in fistula surgery الصح - It originates from the dorsal venous network on the hand - It travels up the medial aspect of the forearm - Halfway between the shoulder and the elbow it lies deep to muscle - It is joined by the brachial vein to form the axillary vein It is used in arteriovenous fistula surgery during a procedure known as a basilic vein transposition.

Question 72

359 of 601 Which of the following is a branch of the third part of the axillary artery?

Answer 72

Posterior circumflex humeral The other branches include: : Subscapular Anterior circumflex humeral The dorsal scapular artery arises from the third part of the subclavian artery in most cases

Question 73

371 of 601 The anterior interosseous nerve is a branch of which of the following?

Answer 73

Median nerve

Question 74

379 of 601 In Froment's test which muscle function is tested?

Answer 74

Adductor pollicis

Question 75

396 of 601 A 36 year old male is admitted for elective surgery for a lymph node biopsy in the supraclavicular region. Post operatively the patient has difficulty shrugging his left shoulder. What is the most likely reason?

Answer 75

Accessory nerve lesion The accessory nerve lies in the posterior triangle and may be injured in this region. Apart from problems with shrugging the shoulder, he may also have difficulty lifting his arm above his head.

Question 75

395 of 601 A 42 year old lady has had an axillary node clearance for breast malignancy. Post operatively she reports weakness of the shoulder. She is unable to push herself forwards from a wall with the right arm and the scapula is pushed out medially from the chest wall. What is the most likely nerve injury?

Answer 75

Long thoracic nerve The patient has a winged scapula caused by damage to the long thoracic nerve (C5,6,7) during surgery. The long thoracic nerve innervates serratus anterior. Serratus anterior causes pushing out of the scapula during a punch. NB winging of the scapular laterally may indicate trapezius muscle weakness. Innervated by the spinal accessory nerve.

Question 76

404 of 601 A 17 year old male presents to the clinic. He complains of difficulty using his left hand. It has been a persistent problem since he sustained a distal humerus fracture as a child. On examination, there is diminished sensation overlying the hypothenar eminence and medial one and half fingers. What is the most likely nerve lesion?

Answer 76

Ulnar nerve This sensory deficit pattern is most consistent with ulnar nerve injury

Question 77

398 of 601 Which of the following muscles is supplied by the musculocutaneous nerve?

Answer 77

Brachialis Mnemonic : Muscles innervated by the musculocutaneous nerve BBC: - Biceps brachii - Brachialis - Coracobrachialis

Question 78

411 of 601 A 72 year old male with end stage critical ischaemia is undergoing an axillo-femoral bypass. What structure is not closely related to the axillary artery?

Answer 78

Scalenus anterior muscle The axillary artery is the continuation of the subclavian artery. It is surrounded by the cords of the brachial plexus (from which they are named). The axillary vein runs alongside the axillary artery throughout its length.

Question 79

419 of 601 Which of the following carpal bones is a sesamoid bone in the tendon of flexor carpi ulnaris?

Answer 79

Pisiform This small bone has a single articular facet. It projects from the triquetral bone at the ulnar aspect of the wrist where most regard it as a sesamoid bone lying within the tendon of flexor carpi ulnaris

Question 80

420 of 601 A 43 year old woman is due to undergo an axillary node clearance following a positive sentinel node biopsy. Which of the nerves below is at greatest risk?

Answer 80

Thoracodorsal The long thoracic nerve is also at risk. The thoracodorsal nerve traverses the level 2 axillary nodes to supply latissimus dorsi and may be divided or damaged with diathermy.

Question 81

421 of 601 A 70 year old man falls and fractures his scaphoid bone. The fracture is displaced and the decision is made to insert a screw to fix the fracture. Which of the following structures lies directly medial to the scaphoid?

Answer 81

Lunate The lunate lies medially in the anatomical plane. Fractures of the scaphoid that are associated with high velocity injuries may cause associated lunate dislocation

Question 82

Question 423 of 601 Which of the muscles listed below would be affected if the radial nerve were injured in a humeral shaft fracture?

Answer 82

Supinator

Question 83

424 of 601 A 73 year old lady is hit by a car. She suffers a complex fracture of the distal aspect of her humerus with associated injury to the radial nerve. Which of the following movements will be most impaired as a result?

Answer 83

Wrist extension The triceps will not be affected so elbow extension will be preserved. Loss of wrist extension will be the most obvious effect

Question 84

428 of 601 A well toned weight lifter attends clinic reporting weakness of his left arm. There is weakness of flexion and supination of the forearm. Which of the following nerves is likely to have been affected?

Answer 84

Musculocutaneous Musculocutaneous nerve compression due to entrapment of the nerve between biceps and brachialis. Elbow flexion and supination of the arm are affected. This is a rare isolated injury

Question 85

430 of 601 An 18 year old man develops a severe spreading sepsis of the hand. The palm is explored surgically and the flexor digiti minimi brevis muscle is mobilised to facilitate drainage of the infection. Which of the following structures is not closely related to this muscle?

Answer 85

Median nerve The flexor digiti minimi brevis originates from the Hamate, on its under- surface lie the ulnar contribution to the superficial palmar arterial arch and digital nerves derived from the ulnar nerve. The median nerve overlies the flexor tendons

Question 86

432 of 601 A 22 year old man develops an infection in the pulp of his little finger. What is the most proximal site to which this infection may migrate?

Answer 86

Proximal to the flexor retinaculum The 5th tendon sheath extends from the little finger to the proximal aspect of the carpal tunnel. This carries a significant risk of allowing infections to migrate proximally

Question 87

433 of 601 Which of the following muscles is not innervated by the deep branch of the ulnar nerve?

Answer 87

Adductor pollicis Hypothenar muscles All the interosseous muscles Opponens pollicis الصح Third and fourth lumbricals

Question 88

436 of 601 During an arch aortogram the brachiocephalic artery is entered with an angiography catheter. The radiologist continues to advance the catheter. Into which of the following vessels is it likely to enter?

Answer 88

Right subclavian artery The axillary artery is a branch of the subclavian artery and although developmental anomalies may occur they are rare. The catheter may also enter the right carotid. There is no brachiocephalic artery on the left side.

Question 89

437 of 601 Which of the following structures lie between the lateral and medial heads of the triceps muscle?

Answer 89

Radial nerve The radial nerve runs in its groove on between the two heads. The ulnar nerve lies anterior to the medial head. The axillary nerve passes through the quadrangular space. This lies superior to lateral head of the triceps muscle and thus the lateral border of the quadrangular space is the humerus. Therefore the correct answer is the radial nerve.

Question 90

438 of 601 Into which of the following structures does the superior part of the fibrous capsule of the shoulder joint insert?

Answer 90

The anatomical neck of the humerus The shoulder joint is a shallow joint, hence its great mobility. However, this comes at the expense of stability. The fibrous capsule attaches to the anatomical neck superiorly and the surgical neck inferiorly

Question 91

443 of 601 The cephalic vein pierces the clavipectoral fascia to terminate in which of the veins listed below?

Answer 91

Axillary

Question 92

449 of 601 A woman develops winging of the scapula following a Patey mastectomy. What is the most likely cause?

Answer 92

Damage to the long thoracic nerve during axillary dissection The serratus anterior muscle is supplied by the long thoracic nerve which runs along the surface of serratus anterior and is liable to injury during nodal dissection. Although pectoralis minor is divided during a Patey mastectomy (now seldom performed) it is rare for this alone to produce winging of the scapula.

Question 93

453 of 601 Which of the following is not closely related to the capitate bone?

Answer 93

Lunate bone Scaphoid bone Ulnar nerve الصح Hamate bone Trapezoid bone The ulnar nerve and artery lie adjacent to the pisiform bone. The capitate bone articulates with the lunate, scaphoid, hamate and trapezoid bones, which are therefore closely related to it.

Question 93

456 of 601 Which nerve supplies sensation to the nail bed of the index finger?

Answer 93

Median

Question 94

457 of 601 An injury to the spinal accessory nerve will have the greatest affect on which of the following movements?

Answer 94

Upward rotation of the scapula The spinal accessory nerve innervates trapezius. The entire muscle will retract the scapula. However, its upper and lower fibres act together to upwardly rotate it.

Question 95

467 of 601 A 28 year teacher reports difficulty with writing. There is no sensory loss. She is known to have an aberrant Gantzer muscle. Which of the following nerves has been affected?

Answer 95

Anterior interosseous Anterior interosseous lesions occur due to fracture, or rarely due to compression. The Gantzer muscle is an aberrant accessory of the flexor pollicis longus and is a risk factor for anterior interosseous nerve compression. Remember loss of pincer grip and normal sensation indicates an interosseous nerve lesion.

Question 96

469 of 601 A 23 year old man falls over whilst intoxicated and a shard of glass transects his median nerve at the proximal border of the flexor retinaculum. His tendons escape injury. Which of the following features is least likely to be present?

Answer 96

Loss of sensation on the dorsal aspect of the thenar eminence The median nerve may be injured proximal to the flexor retinaculum. This will result in loss of abductor pollicis brevis, flexor pollicis brevis, opponens pollicis and the first and second lumbricals. When the patient is asked to close the hand slowly there is a lag of the index and middle fingers reflecting the impaired lumbrical muscle function. The sensory changes are minor and do not extend to the dorsal aspect of the thenar eminence. Abductor pollicis longus will contribute to thumb abduction (and is innervated by the posterior interosseous nerve) and therefore abduction will be weaker than prior to the injury

Question 96

475 of 601 A 23 year old man falls and injures his hand. There are concems that he may have a scaphoid fracture as there is tenderness in his anatomical snuffbox on clinical examination. Which of the following forms the posterior border of this structure?

Answer 96

Extensor pollicis longus It's boundaries are extensor pollicis longus, medially (posterior border) and laterally (anterior border) by the tendons of abductor pollicis longus and extensor pollicis brevis

Question 96

482 of 601 A 44 year old lady who works as an interior decorator has undergone a mastectomy and axillary node clearance to treat breast cancer. Post operatively, she comments that her arm easily becomes fatigued when she is painting walls. What is the most likely explanation?

Answer 96

Injury to the thoracodorsal nerve. The most likely explanation for this is that the thoracodorsal nerve has been injured. This will result in atrophy of latissimus dorsi and this will become evident with repetitive arm movements where the arm is elevated and moving up and down (such as in painting). Injury to the pectoral nerves may produce a similar picture but this pattern of injury is very rare and the pectoral nerves are seldom injured in breast surgery.

Question 97

485 of 601 A 28 year old man is stabbed outside a nightclub in the upper arm. The median nerve is transected. Which of the following muscles will demonstrate impaired function as a result?

Answer 97

Abductor pollicis brevis Palmaris brevis - Ulnar nerve Palmar interossei- Ulnar nerve Adductor pollicis - Ulnar nerve Abductor pollicis longus - Posterior interosseous nerve Abductor pollicis brevis - Median nerve The median nerve innervates all the short muscles of the thumb except the adductor and the deep head of the short flexor Palmaris and the interossei are innervated by the ulnar nerve

Question 98

490 of 601 In the distal third of the upper arm, where is the musculocutaneous nerve located?

Answer 98

Between the biceps brachii and brachialis muscles The musculocutaneous nerve lies between the biceps and brachialis muscles.

Question 99

496 of 601 Which of the following is not a branch of the posterior cord of the brachial plexus?

Answer 99

Musculocutaneous nerve Mnemonic branches off the posterior cord: Subscapular (upper and lower) Thoracodorsal A xillary Radial The musculocutaneous nerve is a branch off the lateral cord

Question 100

501 of 601 A 56 year old machinist has his arm entrapped in a steel grinder and is brought to the emergency department. On examination, he is unable to extend his metacarpophalangeal joints and abduct his shoulder. He has weakness of his elbow and wrist. What has been injured?

Answer 100

Posterior cord of brachial plexus The posterior cord gives rise to: - Radial nerve ((innervates the triceps, brachioradialis, wrist extensors, and finger extensors) - The posterior cord gives rise to Axillary nerve (innervates deltoid and teres minor) - Upper subscapular nerve (innervates subscapularis) - Lower subscapular nerve (innervates teres major and subscapulans) - Thoracodorsal nerve (innervates latissimus dorsi) This is a description of a posterior cord lesion. Remember that the posterior cord gives rise to the axillary and radial nerve

Question 101

509 of 601 A motor cyclist is involved in a road traffic accident causing severe right shoulder injuries. He is found to have an adducted, medially rotated shoulder. The elbow is fully extended and the forearm pronated. Which is the most likely diagnosis?

Answer 101

C5, C6 root lesion Erbs Palsy C5, C6 lesion The features include: - Waiter's tip position - Loss of shoulder abduction (deltoid and supraspinatus paralysis) - Loss of external rotation of the shoulder (paralysis of infraspinatus) - Loss of elbow flexion (paralysis of biceps, brachialis and brachioradialis) - Loss of forearm supination (paralysis of Biceps) The motorcyclist has had an Erb's palsy (C5, C6 root lesion). This is commonly known to be associated with birth injury when a baby has a shoulder dystocia

Question 102

515 of 601 A man sustains a laceration between the base of the little finger and wrist. Several weeks after the injury there is loss of thumb adduction power. Which nerve is most likely to have been injured?

Answer 102

Deep ulnar nerve

Question 103

517 of 601 A 23 year old man has a cannula inserted into his cephalic vein. Through which structure does the cephalic vein pass?

Answer 103

Clavipectoral fascia The cephalic vein is a favored vessel for arteriovenous fistula formation patients with end stage renal failure and should be preserved in pateint with ESRD The cephalic vein penetrates the clavipectoral fascia (but not the pectoralis major) prior to terminating in the axillary vein.

Question 104

519 of 601 Which of the following is not a carpal bone?

Answer 104

Trapezius Mnemonic for the Carpal Bones: Sally Likes To Play The Tiny Chrome Harmonica She Looks Too Pretty Try To Catch Her Scared Lovers Try Positions That They Can't Handle Trapezius is a muscle of the back.

Question 105

526 of 601 Which of these muscles is not a component of the rotator cuff?

Answer 105

Deltoid Deltoid may abduct the shoulder and is not a rotator cuff muscle

Question 106

535 of 601 A 32 year old man is stabbed in the neck and the inferior trunk of his brachial plexus is injured. Which of the modalities listed below is least likely to be affected?

Answer 106

Initiating abduction of the shoulder Inferior trunk of brachial plexus - C8 and T1 roots - Contributes to ulnar nerve and part of median nerve The inferior trunk of the brachial plexus is rarely injured. Nerve roots C8 and T1 are the main contributors to this trunk. Therefore an injury to this site will most consistently affect the ulnar nerve. The inferior trunk also contributes to the median nerve by way of the medial cord and therefore some impairment of grip is almost inevitable

Question 107

536 of 601 A 42 year old teacher is admitted with a fall. An x-ray confirms a fracture of the surgical neck of the humerus. Which nerve is at risk?

Answer 107

Axillary The Axillary nerve winds around the bone at the neck of the humerus. The axillary nerve is also at risk during shoulder dislocation

Question 108

544 of 601 As it exits the axilla the radial nerve lies under which of the following muscles?

Answer 108

Teres major The radial nerve passes through the triangular interval to leave the axilla. The superior border of this is bounded by the teres major muscle to which the radial nerve is closely related.

Question 108

547 of 601 A 62 year old man presents with arm weakness. On examination, he has a weakness of elbow extension and loss of sensation on the dorsal aspect of the first digit. What is the site of the most likely underlying defect?

Answer 108

Radial nerve The long head of the triceps muscle may be innervated by the axillary nerve and therefore complete loss of triceps muscles function may not be present even with proximally sited nerve lesions

Question 109

548 of 601 From which of the following structures does the long head of the triceps muscle arise?

Answer 109

Infraglenoid tubercle The long head arises from the infraglenoid tubercle. The fleshy lateral and medial heads are attached to the posterior aspect of the humerus between the insertion of the teres minor and the olecranon fossa.

Question 110

556 of 601 A 58 year old lady presents with a mass in the upper outer quadrant of the right breast. Which of the following statements relating to the breast is untrue?

Answer 110

- The internal mammary artery provides the majority of its arterial supply - Nipple retraction may occur as a result of tumour infiltration of the clavipectoral fascia الصح - The internal mammary artery is a branch of the subclavian artery - Up to 70% of lymphatic drainage is to the ipsilateral axillary nodes - None of the above Both skin dimpling and nipple retraction are features of breast malignancy. However, they usually occur as a result of tumour infiltration of the breast ligaments and ducts respectively. The clavipectoral fascia encases the axillary contents. The lymphatic drainage of the breast is to the axilla and also to the internal mammary chain. The breast is well vascularised and the internal mammary artery is a branch of the subclavian artery.

Question 111

562 of 601 A 78 year old man is lifting a heavy object when he feels a pain in his forearm and is unable to continue. He has a swelling over his upper forearm. An MRI scan shows a small cuff of tendon still attached to the radial tuberosity consistent with a recent tear. Which of the following muscles has been injured?

Answer 111

Biceps brachii Biceps inserts into the radial tuberosity. Distal injuries of this muscle are rare but are reported and are clinically more important than more proximal ruptures

Question 112

564 of 601 A 53 year old lady presents with pain and discomfort in her hand. She works as a typist and notices that the pain is worst when she is working. She also suffers symptoms at night. Her little finger is less affected by the pain. Which of the nerves listed below is most likely to be affected?

Answer 112

Median Motor supply: LOAF - Lateral 2 lumbricals - O pponens pollicis - A bductor pollicis brevis. - Flexor pollicis brevis The most likely diagnosis here is carpal tunnel syndrome, the median nerve is compressed in the wrist and symptoms usually affect the fingers and wrist either at night or when the hand is being used (e.g. as a typist).

Question 113

565 of 601 Which of the following muscles lies medial to the long thoracic nerve?

Answer 113

Serratus anterior

Question 114

572 of 601 A 24 year female is admitted to A&E with tingling of her hand after a fall. She is found to have a fracture of the medial epicondyle. What is the most likely nerve lesion?

Answer 114

Ulnar nerve The radial nerve is located near the lateral epicondyle.

Question 115

579 of 601 A 44 year old lady has undergone a mastectomy and axillary node clearance. Post operatively, she notices a patch of anaesthesia of her axillary skin when she applies an underarm deodorant. Which nerve has most likely been affected?

Answer 115

Intercostobrachial The intercostobrachial nerves traverse the axilla and innervate the overlying skin. These can be injured or divided during axillary surgery and the result is anaesthesia of the overlying skin

Question 116

588 of 601 A 43 year old lady is undergoing an axillary node clearance for breast cancer. The nodal disease is bulky. During clearance of the level 3 nodes there is suddenly brisk haemorrhage. The most likely vessel responsible is:

Answer 116

Thoracoacromial artery The thoracoacromial artery pierces the pectoralis major and gives off branches within this space. The level 3 axillary nodes lie between pectoralis major and minor. Although the thoracodorsal trunk may be injured during an axillary dissection it does not lie within the level 3 nodes.

Question 117

589 of 601 A 73 year old lady with long standing atrial fibrillation develops a cold and pulseless white arm, A brachial embolus is suspected and a brachial embolectomy is performed. Which of the following structures is at greatest risk of injury during this procedure?

Answer 117

Median nerve The median nerve lies close to the brachial artery in the antecubital fossa. This is the usual site of surgical access to the brachial artery for an embolectomy procedure. The median nerve may be damaged during clumsy application of vascular clamps to the artery

Question 118

591 of 601 Which of the following fingers is not a point of attachment for the palmar interossei?

Answer 118

Middle finger The middle finger has no attachment of the palmar interosseous.

Question 119

592 of 601 A 33 year old man sustains an injury to his forearm and wrist. When examined in clinic he is unable to adduct his thumb. What is the most likely underlying nerve lesion?

Answer 119

Deep branch of the ulnar nerve Damage to the deep branch of the ulnar nerve may result in an inability to adduct the thumb. This is tested clinically by trying to withdraw a piece of paper from a patients hand grasped between thumb and index finger.

Question 120

593 of 601 A 6 year old sustains a supracondylar fracture of the distal humerus. There are concems that the radial nerve may have been injured. What is the relationship of the radial nerve to the humerus at this point?

Answer 120

Anterolateral The radial nerve lies anterolateral to the humerus in the supracondylar area.

Question 121

595 of 601 The following are true of the ulnar nerve except

Answer 121

- It innervates the palmar interossei - Derived from the medial cord of the brachial plexus - Supplies the muscles of the thenar eminence الصح - Supplies the medial half of flexor digitorum profundus - Passes superficial to the flexor retinaculum The muscles of the thenar eminence are supplied by the median nerve and atrophy of these is a feature of carpal tunnel syndrome