It is one of eight bones that form the carpus in the hand. The triquetrum is between the lunate and pisiform bones which are two other carpal bones located right above the end of the ulna, a major bone in the arm.

It is partly covered by the pisiform bone. Its functional ability is not dependent on the ulna. It acts together with the ulnar collateral ligament and the pisiform carpal bone. It also articulates with the hamate bone. It has five different sections designated on the three distinctly recognizable sides of the bone. It is also called the triquetral bone.