Base of Proximal Phalanx of Index Finger

Description

The base is the expanded proximal end of the proximal phalanx of the index finger. It is the proximal continuation of its body and contains a proximal articular facet, which articulates with the distal articular facet of the second metacarpal bone, forming the second metacarpophalangeal joint.

The base of the proximal phalanx of the index finger provides insertion sites for the:

—first palmar interosseous muscle of hand;

—first dorsal interosseous muscle of hand.

It also provides attachment sites for the collateral and palmar ligaments of the second metacarpophalangeal joint.