Upper Limb B Flashcards
Question 182 of 328 The cephalic vein pierces the clavipectoral fascia to terminate in which of the veins listed below? A. External jugular B. Axillary C. Internal jugular D. Azygos E. Brachial
Axillary
Question 187 of 328 Damage to the posterior cord of the brachial plexus will not result in any of the following except: A. Klumpkes palsy B. Anaesthesia overlying the lateral aspect of the forearm C. A warm sweaty hand on the affected side
Anaesthesia overlying the posterior surface of the armThe radial nerve gives cutaneous branches which supply the forearm posteriorly and the arm laterally. Division of the posterior cord will impair the upper level of cutaneous sensation. However, the lateral cutaneous nerve of the forearm arises from the musculocutaneous nerve and would be unaffected. Loss of sympathetic function, from the posterior cord alone, would not result in a sweaty hand. Klumpkes palsy occurs when the lower roots are C8-T1 are damaged.
Question 189 of 328 A woman develops winging of the scapula following a Patey mastectomy. What is the most likely cause? A. Division of pectoralis minor to access level 3 axillary nodes B. Damage to the brachial plexus during axillary di
Damage to the long thoracic nerve during axillary dissection
Question 192 of 328 Which of the following is not closely related to the capitate bone? A. Lunate bone B. Scaphoid bone C. Ulnar nerve D. Hamate bone E. 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 202 of 328 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 pre
Loss of sensation on the dorsal aspect of the thenar eminenceThe median nerve may be injured proximal to the flexor retinaculum. This will result in loss of 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 206 of 328 Which of the following relationship descriptions regarding the scalene muscles is incorrect? A. The brachial plexus passes anterior to the middle scalene muscle B. The phrenic nerve lies anterior to the anterior scalene mu
The subclavian artery passes anterior to the middle scalene.
Question 208 of 328 A 23 year old man falls and injures his hand. There are concerns 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
Extensor pollicis longusTheme from 2009 ExamTheme from September 2012 ExamIts boundaries are extensor pollicis longus, medially (posterior border) and laterally (anterior border) by the tendons of abductor pollicis longus and extensor pollicis brevis.
Question 218 of 328 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? A. Palmaris brevis B. Second and third inter
Abductor pollicis brevisPalmaris brevis - Ulnar nervePalmar interossei- Ulnar nerveAdductor pollicis - Ulnar nerveAbductor pollicis longus - Posterior interosseous nerveAbductor pollicis brevis - Median nerveThe 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 228 of 328 Which of the following is not a branch of the posterior cord of the brachial plexus? A. Thoracodorsal nerve B. Axillary nerve C. Radial nerve D. Lower subscapular nerve E. Musculocutaneous nerve
Musculocutaneous nerveMnemonic branches off the posterior cordS ubscapular (upper and lower)T horacodorsalA xillaryR adialThe musculocutaneous nerve is a branch off the lateral cord.
Question 233 of 328 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
Posterior cord of brachial plexusThe posterior cord gives rise to: Radial nerve ((innervates the triceps, brachioradialis, wrist extensors, and finger extensors) Axillary nerve (innervates deltoid and teres minor) Upper subscapular nerve (innervates subscapularis) Lower subscapular nerve (innervates teres major and subscapularis) Thoracodorsal nerve (innervates latissimus dorsi) Theme from September 2012 examThis is a description of a posterior cord lesion. Remember that the posterior cord gives rise to the axillary and radial nerve.
Question 241 of 328 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 lik
. C5, C6 root lesionErbs Palsy C5, C6 lesionThe features include: Waiter’s tip position Loss of shoulder abduction (deltoid and supraspinatus paralysis) Loss of external rotation of the shoulder (paralysis of infraspinatus and teres major) 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 248 of 328 A 23 year old man has a cannula inserted into his cephalic vein. Through which structure does the cephalic vein pass? A. Interosseous membrane B. Triceps C. Pectoralis major D. Clavipectoral fascia E. Tendon o
Clavipectoral fasciaThe cephalic vein is a favored vessel for arteriovenous fistula formation and should be preserved in patients with end stage renal failureThe cephalic vein penetrates the calvipectoral fascia (but not the pectoralis major) prior to terminating in the axillary vein.
Question 250 of 328 Which of the following is not a carpal bone? A. Trapezium B. Triquetrum C. Trapezoid D. Trapezius E. Lunate
TrapeziusMnemonic for the Carpal BonesSally Likes To Play The Tiny Chrome HarmonicaShe Looks Too Pretty Try To Catch HerScared Lovers Try Positions That They Can’t Handle
Question 268 of 328 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? A. Initiating abduction of the shoulder B. Abduction o
Initiating abduction of the shoulderInferior trunk of brachial plexus. C8 and T1 roots Contributes to ulnar nerve and part of median nerveTheme from September 2012 ExamThe 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 posterior division and therefore some impairment of grip is almost inevitable.
Question 278 of 328 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? A. A
Radial nerveTheme from April 2012 ExamThe 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.