Midcarpal Joint (Left)

Description

The intercarpal joints consist of:

—the carpal joints between the proximal row of carpal bones

—the carpal joints between the distal row of carpal bones

—the articulations between the proximal and distal carpal bones which is termed the midcarpal joint.

The midcarpal joint is a compound articulation formed between the proximal and distal rows of carpal bones. The proximal row is composed of the scaphoid, lunate, and triquetrum, while the distal row is formed by the trapezium, trapezoid, capitate, and hamate. The articulation may be divided into medial and lateral compartments. The head of the capitate and hamate form a convex articulation for the concave scaphoid, lunate, and triquetrum, except most medially, where the curvatures are reversed to form a compound sellar joint. In the lateral compartment, the trapezium and trapezoid articulate with the scaphoid, thus also forming a compound articulation. The midcarpal joint is also a synovial joint.

Numerous midcarpal ligaments help to stabilize the midcarpal joint and may be referred to as intrinsic ligaments of the wrist. Generally, they are stronger and shorter than the extrinsic ligaments, but often form a complex with one another by interdigitating fibers. The midcarpal ligaments include the dorsal, palmar, and interosseous intercarpal ligaments.

Extension and abduction of the hand occur primarily at the midcarpal joint, while flexion and extension of the hand are imitated at the midcarpal joint.