A 20-year-old male athlete complains of pain and weakness of his right arm. He had a successful surgery on his knee last week. He has been walking with the aid of crutches since then. On examination, he is unable to extend his right arm at the elbow or the hand at the wrist. There is also a sensory deficit over the dorsolateral area of the right hand. Neurological examination is otherwise normal.
Which nerve is most likely related to his symptoms?
A-Axillary nerve
B-Median nerve
C-Radial nerve
D-Suprascapular nerve
E-Ulnar nerve
Answer
This is a typical presentation of radial nerve palsy caused by the compression of the crutches on the radial nerve. It is also called crutch paralysis. Crutch paralysis occurs when the radial nerve becomes under constant pressure by the use of a crutch. It leads to paralysis of the muscles that innervated by the compressed nerve. Generally, crutches which are not adjusted to the correct height causes the radial nerve to be constantly pushed against the humerus. This can cause wrist drop, in which the fingers, hand, or wrist is flexed because the radial nerve cannot innervate the extensor muscles. This condition, like other injuries from compressed nerves, normally improves quickly without any consequences.
The correct answer is C