Os capitatum

The capitate bone is found in the center of the carpal bone region, colloquially known as the wrist, which is at the distal end of the radius and ulna bones.

It articulates with the third metacarpal bone (the middle finger) and forms the third carpometacarpal joint.

The capitate bone is the largest of the carpal bones in the human hand.

It presents, above, a rounded portion or head, which is received into the concavity formed by the scaphoid and lunate bones; a constricted portion or neck; and below this, the body.

The bone is also found in many other mammals, and is homologous with the "third distal carpal" of reptiles and amphibians.