What joint produces abduction and adduction of the phalanges?

The metacarpophalangeal joints are located between the metacarpal bones of the hand and the proximal phalanges of the fingers. These joints are significant because they allow for a wide range of motion, including flexion, extension, and importantly, abduction and adduction of the phalanges.

Abduction refers to the movement of the fingers away from the midline of the hand, while adduction is the movement toward the midline. The structure of the metacarpophalangeal joints, which are synovial joints with a saddle-like configuration, facilitates these movements effectively. The intrinsic muscles of the hand, such as the dorsal interossei and palmar interossei, play crucial roles in enabling these motions at the metacarpophalangeal level.

The other joints mentioned—distal interphalangeal, proximal interphalangeal, and carpometacarpal—primarily allow for flexion and extension. While the carpometacarpal joints are involved in thumb opposition and some limited movement, they do not significantly contribute to the abduction and adduction of the phalanges like the metacarpophalangeal joints do. Thus, the metac