Palmar interossei action?

Palmar interossei action?

• A. Abduct digits 2,3,4
• B. Adduct digits 2,4,5
• C. Flex digits 2,3
• D. Extend IP joints

Answer: (B)

Palmar interossei mainly bring the digits toward the middle finger, i.e., they adduct digits 2, 4, and 5 toward digit 3. They lie between the metacarpals on the palmar side and insert into the bases of the proximal phalanges and the extensor expansions of those same digits. In addition to adduction, they help flex the metacarpophalangeal joints and, via the extensor expansions, assist in extending the interphalangeal joints. Abduction of the fingers is done by the dorsal interossei, not the palmar ones. So the best description of their action is adduction of digits 2, 4, and 5 toward the middle finger.

Palmar interossei mainly bring the digits toward the middle finger, i.e., they adduct digits 2, 4, and 5 toward digit 3. They lie between the metacarpals on the palmar side and insert into the bases of the proximal phalanges and the extensor expansions of those same digits. In addition to adduction, they help flex the metacarpophalangeal joints and, via the extensor expansions, assist in extending the interphalangeal joints. Abduction of the fingers is done by the dorsal interossei, not the palmar ones. So the best description of their action is adduction of digits 2, 4, and 5 toward the middle finger.