Hamate

The Hamate bone is one of the four bones that comprise the distal row of the carpus or carpal bones that form the wrist. The name arises from the Latin [hamatus], meaning "hooked". The hamate bone has a distinct hook-like bony process in its volar (anterior) surface, known as the hamulus. This bone is also known as the "unciform bone" (from the Latin [uncus], also meaning "hook") or the os hamatum.

The lunate bone has a wedge-like shape and six surfaces (as a die). It articulates with five bones, including the lunate bone, capitate, triquetrum, and the fourth and fifth metacarpal bones.

The hook of the hamate bone is one of the distal boundaries of the carpal tunnel and serves as a pulley for the tendons of the fourth and fifth flexor tendons. It also serves as one of the points of muscular attachment for the following muscles: flexor carpi ulnaris, flexor digit minimi, and opponens digiti minimi. Because of its projection into the palm of the hand, the hamulus is involved in injuries in sports that require the athlete to use an accessory, as in racquetball, tennis, baseball, golf, etc.

The accompanying image shows the anterior (volar) surface of the wrist. Click on the image for a larger picture.

Scaphoid bone - anterior (volar) view of the wrist

Image modified from the original: "3D Human Anatomy: Regional Edition DVD-ROM." Courtesy of Primal Pictures