- There are eight carpal bones of the wrist, arranged in two rows of four.
- proximal row (radial to ulnar) : scaphoid, lunate, triquetrum, pisiform
- distal row (radial to ulnar) : trapezius, trapezoid, capitate, hamate
- The carpals articulate with:
- the radius primarily, but also with the ulna proximally, forming the wrist joint (radiocarpal, ulnocarpal joints).
- the metacarpals distally, forming the carpometacarpal joints.
- Specifically, the joint between the trapezius and the metacarpal of the thumb is the 1st carpometacarpal joint, aka the famous saddle joint of the thumb.
NOTES:
- The walls of the carpal tunnel are formed by the tubercles of the scaphoid and trapezium laterally and the pisiform and the hook of the hamate medially.
- There is a mnemonic for learning the carpal bones: Some Lovers Try Positions That They Can’t Handle. Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate.
Anterior view of bones of the wrist and hand on the right side.
Posterior view of bones of the wrist and hand on the right side.
Anterior view of the carpals spaced out, on the right side of the body.
Posterior view of the carpals spaced out, on the right side of the body.
Proximal to distal view of the bones of the carpal tunnel on the right side of the body.
Bones of the wrist and hand in the posture of a fist on the right side.
