QuestionSBA
QuestionChoice
Klumpke’s palsy, or injury to the C8-T1 nerve root, is often caused by traumatic hyperabduction of the arm. Patients with Klumpke’s palsy have a characteristic ‘claw hand’, with a supinated forearm, extended wrist and flexed fingers (due to paralysis of intrinsic hand muscles, flexor carpi ulnaris and ulnar half of flexor digitorum profundus).
10027005
e
C8-T1 nerve root
QuestionChoice
This is a classical history of radial nerve injury, which often occurs in association with humeral fractures, ‘Saturday night palsy’ or improper use of crutches. Injury to the radial nerve results in loss of extensor function, or ‘wrist drop’, and loss of sensation on the posterior forearm, elbow and dorsum of the hand.
10027001
a
Radial nerve
QuestionChoice
Damage to the C5-6 nerve root is also known as Erb’s palsy, which can occur during traumatic lateral bending of the neck, for example during childbirth or a fall. Flaccid muscle paralysis and atrophy of the supraspinatus, infraspinatus, deltoid, biceps and brachialis muscles are seen, resulting in an adducted, medially rotated arm and extended pronated forearm.
10027004
d
C5-6 nerve root
QuestionChoice
Damage to the median nerve would result in signs such as an inability to pronate the forearm, weak wrist flexion and ulnar deviation of the wrist. It also causes an inability to flex the distal interphalangeal joints of the second and third digits, resulting in the characteristic ‘Pope blessing’ sign when the patient is asked to make a fist.
10027002
b
Median nerve
QuestionChoice
Damage to the ulnar nerve results in a ‘claw hand’ deformity. The ulnar nerve innervates most intrinsic muscles of the hand (apart from the thenar eminence and the lateral two lumbricals), therefore its damage results in metacarpophalangeal joint extension and flexion of the 4th and 5th digit interphalangeal joints. Wasting and paralysis of the hypothenar eminence and other intrinsic hand muscles innervated by the ulnar nerve would also be seen. Sensory loss or changes would be in the ulnar distribution (palmar and dorsal aspects of the medial 1.5 digits).
10027003
c
Ulnar nerve
Concept
Chapter
2693
3950
Radial nerve injuries
Topic
145
Orthopaedics
17798
A 26-year-old man experiences ‘wrist drop’ and loss of sensation to his posterior forearm, elbow and dorsum of his hand following a fracture of his humeral shaft.

Which structure is most likely to have been damaged?
a