During upper-extremity wound assessment, which nerve is evaluated when the digits are adducted and abducted?

During upper-extremity wound assessment, which nerve is evaluated when the digits are adducted and abducted?

• A. Radial
• B. Median
• C. Axillary
• D. Ulnar

Answer: (D)

Adduction and abduction of the digits are controlled by the intrinsic hand muscles called the interossei. The dorsal interossei abduct fingers (move away from the middle finger) and the palmar interossei adduct fingers (move toward the middle finger). Both groups are innervated by the ulnar nerve. So testing whether you can spread or bring the fingers together directly evaluates ulnar nerve function. The radial nerve mainly handles wrist and finger extension; the median nerve controls the lateral lumbricals and thenar muscles; the axillary nerve supplies the deltoid. Thus, the ability to adduct and abduct the digits points to the ulnar nerve.

Adduction and abduction of the digits are controlled by the intrinsic hand muscles called the interossei. The dorsal interossei abduct fingers (move away from the middle finger) and the palmar interossei adduct fingers (move toward the middle finger). Both groups are innervated by the ulnar nerve. So testing whether you can spread or bring the fingers together directly evaluates ulnar nerve function. The radial nerve mainly handles wrist and finger extension; the median nerve controls the lateral lumbricals and thenar muscles; the axillary nerve supplies the deltoid. Thus, the ability to adduct and abduct the digits points to the ulnar nerve.