Capitate Bone

Key Features & Anatomical Relations

The capitate is the largest of the eight carpal bones of the hand. It’s head-shaped and is found in the distal row of carpal bones. It’s classified as a short bone and includes the following bony features:

- parts: head and base;

- surfaces: palmar and dorsal surfaces;

- landmarks: trapezoid, scaphoid, lunate, and hamate articular facets, and the second, third, and fourth metacarpal articular facets.

More information regarding these bony features can be found in the Parts, Surfaces and Landmarks tabs for this bone.

The capitate bone is located:

- proximal to the second, third, and fourth metacarpal bones;

- distal to the lunate bone;

- medial to the scaphoid and trapezoid bones;

- lateral to the hamate bone.

It articulates with the:

- trapezoid bone at the trapeziocapitate joint;

- scaphoid bone at the scaphocapitate joint;

- lunate bone at the lunocapitate joint;

- hamate at the capitohamate joint;

- second, third and fourth metacarpal bones, contributing to the formation of the carpometacarpal joints.

Ossification

Ossification of the capitate bone occurs at one ossification center, which appears within the second month after birth (Standring, 2016). Complete ossification occurs during early adolescence.

Variations

In some individuals:

- carpal fusion, or coalition, between the capitate and hamate bones may be present, forming the capitohamate bone;

- an accessory bone, known the os centrale, may be present between the scaphoid, capitate and trapezoid bones (Tubbs, Shoja and Loukas, 2016).

Surface Anatomy

With regard to surface anatomy, the capitate bone can be palpated on the dorsal aspect of the wrist, proximal to the third metacarpal bone.

List of Clinical Correlates

- Fracture of capitate bone

References

Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.

Tubbs, R. S., Shoja, M. M. and Loukas, M. (2016) Bergman's Comprehensive Encyclopedia of Human Anatomic Variation. Wiley.