Assh: Reconstructive Options For Peripheral Nerve Injuries

1. A 43 year old gentleman sustains a through and through gunshot injury to his left distal forearm. Surprisingly, there is no bony or vascular injury but he has weakness in thumb opposition and numbness over the thumb, index, long and radial border of his ring finger. You suspect a complete median nerve injury. His ability to partially oppose the thumb may be due to functioning of:

A. APB

B. ADM

C. FPB

D. Opponens pollicis

The ability of the patient to partially oppose the thumb despite a complete median nerve injury suggests that the flexor pollicis brevis (FPB) muscle is still functioning. The FPB muscle is innervated by the median nerve, so if the patient is able to partially oppose the thumb, it indicates that the motor function of the median nerve is still intact in this muscle. This finding helps confirm the diagnosis of a complete median nerve injury.

Explanation

The ability of the patient to partially oppose the thumb despite a complete median nerve injury suggests that the flexor pollicis brevis (FPB) muscle is still functioning. The FPB muscle is innervated by the median nerve, so if the patient is able to partially oppose the thumb, it indicates that the motor function of the median nerve is still intact in this muscle. This finding helps confirm the diagnosis of a complete median nerve injury.

2. You are called to see an 18 year old gentleman in the ER after he has been stabbed in posterior aspect of the arm. He has an obvious wrist drop. Suspecting an injury to the radial nerve, you decide to take the patient to the operating room where you find a transected radial nerve that is primarily repaired without tension. In discussing the prognosis for recovery with him, the factor that is most closely linked to his recovery is:

A. Mechanism of injuryflaps, tissue expansion, free flap

B. Time to repair

C. His age

D. Level of injury

The factor that is most closely linked to the patient's recovery is his age. Younger patients generally have a better prognosis for nerve recovery compared to older patients. Age can affect the regenerative capacity of nerves and the overall healing process. Therefore, in this case, the patient's age of 18 years suggests a better chance for recovery of the transected radial nerve.

Explanation

The factor that is most closely linked to the patient's recovery is his age. Younger patients generally have a better prognosis for nerve recovery compared to older patients. Age can affect the regenerative capacity of nerves and the overall healing process. Therefore, in this case, the patient's age of 18 years suggests a better chance for recovery of the transected radial nerve.

3. A 65 year old gentleman presents with gradual loss of functioning of his right hand, especially with fine motor skills such as buttoning his shirt. He has wasting of his intrinsic muscles, difficulty adducting his digits and numbness of his small finger. He has minimal clawing. Given these findings, you suspect injury to his ulnar nerve at the:

A. Distal ulnar tunnel

B. Distal forearm

C. Mid forearm

D. Distal arm

Based on the symptoms described, it is likely that the patient has a injury to his ulnar nerve at the distal arm. The wasting of intrinsic muscles, difficulty adducting digits, numbness of the small finger, and minimal clawing are all consistent with ulnar nerve dysfunction. The distal arm is the most likely location of the injury as it is the area where the ulnar nerve travels before branching into the hand. The other options (distal ulnar tunnel, distal forearm, mid forearm) are less likely as they are not consistent with the specific symptoms described.

Explanation

Based on the symptoms described, it is likely that the patient has a injury to his ulnar nerve at the distal arm. The wasting of intrinsic muscles, difficulty adducting digits, numbness of the small finger, and minimal clawing are all consistent with ulnar nerve dysfunction. The distal arm is the most likely location of the injury as it is the area where the ulnar nerve travels before branching into the hand. The other options (distal ulnar tunnel, distal forearm, mid forearm) are less likely as they are not consistent with the specific symptoms described.