What condition does drop wrist deformity typically indicate?

• A. Palsy of the median nerve
• B. Palsy of the radial nerve
• C. Palsy of the ulnar nerve
• D. Palsy of the axillary nerve

Answer: (B)

Drop wrist deformity is primarily associated with palsy of the radial nerve. This condition occurs when there is a weakness or paralysis of the wrist and finger extensors, which are predominantly innervated by the radial nerve. As a result, the affected individual is unable to extend the wrist, leading to the characteristic appearance of the wrist drooping or falling into a flexed position. This can significantly impair hand function, as the person may struggle to grasp objects or maintain a neutral position of the hand.

In contrast, the other options involve different nerves with distinct functions and patterns of associated symptoms. The median nerve primarily affects the ability to perform thumb opposition and may lead to symptoms such as carpal tunnel syndrome, while the ulnar nerve is more related to the function of the ring and little fingers, causing issues such as claw hand. The axillary nerve, on the other hand, is responsible for shoulder abduction and sensation in the deltoid region, so its impairment is not related to wrist function. Therefore, the presence of a drop wrist deformity strongly signifies damage to the radial nerve.