Carpal tunnel syndrome of the thumb, and the hamate hook that can be palpated along the axis of the ring finger. From the anatomical position, the carpal tunnel is bordered on the anterior surface by the transverse carpal ligament, also known as the flexor retinaculum. The flexor retinaculum is a strong, fibrous band that attaches to the pisiform and the hamulus of the hamate. The proximal boundary is the distal wrist skin crease, and the distal boundary is approximated by a line known as Kaplan's cardinal line. This line uses surface landmarks, and is drawn between the apex of the skin fold between
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