Pisiform bone joint, articulating with the triquetral bone. It is on a plane anterior to the other carpal bones and is spheroidal in form. The pisiform bone has four surfaces: Unlike the other carpal bones, the pisiform is not involved in movement of the wrist. The etymology derives from the Latin "pīsum" which means "pea". All other tetrapods have pisiform, being the most common sesamoid. As compared with apes, which have an elongated Pisiform, humans have a shorter pisiform bone. This is due to the loss of the single growth plate typically found in other mammalian pisiforms. This may be because of
Hamate bone of the hand. The ossification of the hamate starts between 1 and 12 months. The hamate does not fully ossify until about the 15th year of life. The bone is also found in many other mammals, and is homologous with the "fourth distal carpal" of reptiles and amphibians. The carpal bones function as a unit to provide a bony superstructure for the hand. The hamate bone is the bone most commonly fractured when a golfer hits the ground hard with a golf club on the downswing or a hockey player hits the ice with a slap shot. The fracture is