Pisiform bone evolutionary benefits from having a shorter pisiform bone, including facilitating ulnar deviation of the hand and preventing hyperextension of the wrist, motions that improve the action of clubbing. Pisiform bone The pisiform bone ( or ), also spelled pisiforme (from the Latin "pisifomis", pea-shaped), is a small knobbly, sesamoid bone that is found in the wrist. It forms the ulnar border of the carpal tunnel. The pisiform is a sesamoid bone, with no covering membrane of periosteum. It is the last carpal bone to ossify. The pisiform bone is a small bone found in the proximal row of the wrist
Human skeleton Human skeleton The human skeleton is the internal framework of the body. It is composed of around 270 bones at birth – this total decreases to around 206 bones by adulthood after some bones get fused together. The bone mass in the skeleton reaches maximum density around age 21. The human skeleton can be divided into the axial skeleton and the appendicular skeleton. The axial skeleton is formed by the vertebral column, the rib cage, the skull and other associated bones. The appendicular skeleton, which is attached to the axial skeleton, is formed by the shoulder girdle, the pelvic girdle