Pisiform

A small, pea-shaped bone located in the wrist, contributing to its complex structure.

The pisiform is one of the eight carpal bones in the wrist, classified as a sesamoid bone due to its rounded shape. It is situated in the proximal row of the carpal bones and plays a crucial role in wrist function and movement.

Terminologia Anatomica

os pisiforme

System

Skeletal system

Function

The pisiform serves several essential functions within the wrist. It acts as an anchor point for various ligaments and tendons, particularly the flexor carpi ulnaris tendon, which helps facilitate wrist flexion and ulnar deviation. Its location enhances the mechanical advantage of associated muscles, allowing for improved range of motion and strength during wrist movements. In addition to its role in muscle attachment, the pisiform aids in forming the wrist joint, contributing to the overall stability of the carpal structure. This stability is crucial for the functioning of the hand, as the wrist supports a wide range of movements essential for daily activities.

Location

The pisiform bone is located on the palm side of the wrist, specifically at the proximal end of the ulnar side. It sits atop the triquetrum bone and is easily palpable beneath the skin, often felt in the wrist when pressure is applied to the area. The pisiform's unique position allows it to interact with other carpal bones, while also being a key landmark for identifying other anatomical structures in the wrist region.

Did You Know?

The pisiform is the only carpal bone that is not part of the wrist joint but instead functions as a site for muscle attachment.
In some individuals, the pisiform can be larger or smaller than average, which may affect wrist function.
Due to its shape, the pisiform can help cushion the impact and stress placed on the wrist during various activities.