capitate

Capitate refers primarily to the capitate bone, or os capitatum, the largest of the eight carpal bones in the human wrist. It sits at the center of the carpal bones in the distal row, between the trapezoid bone laterally and the hamate bone medially. Its proximal surface articulates with the scaphoid and lunate, while its distal end forms the base of the third metacarpal. The capitate has a rounded head that contributes to the wrist’s central column and helps anchor the carpal arc.

Anatomy and function: The capitate is the keystone of the carpal architecture. Its central position allows it to transmit axial loads from the hand into the forearm, particularly through the third metacarpal. By articulating with multiple neighboring bones, it helps coordinate a range of wrist movements, including flexion, extension, and some rotational components.

Clinical significance: Capitate fractures are uncommon but clinically important due to potential complications such as avascular necrosis from its retrograde blood supply, nonunion, or post-traumatic arthritis. Fractures can result from falls on an outstretched hand or high-energy trauma. Diagnosis relies on radiographs, sometimes with additional imaging (CT or MRI). Treatment ranges from immobilization for stable fractures to surgical fixation for displaced or unstable injuries, aiming to preserve carpal alignment and function.

Etymology and other uses: The term capitate derives from Latin caput, meaning head. In broader use, capitate can function as an adjective meaning head-shaped, and as a rare verb meaning to decapitate, though this usage is obsolete in modern medical or scientific writing.

In summary, the capitate is the wrist’s largest central carpal bone, essential for load transmission and wrist mobility, with specific clinical attention given to its fractures due to potential vascular and functional consequences.