- The metacarpophalangeal (MCP) joints of the hand are located between the metacarpals and the proximal phalanges of the fingers (including the thumb).
- There are five metacarpophalangeal joints named #1-5, from the lateral thumb side to the medial little-finger side.
- The metacarpophalangeal joints are synovial, diarthrotic, biaxial, condyloid joints.
- They allow:
- flexion/extension of the fingers in the sagittal plane.
- abduction/adduction of the fingers in the frontal plane.
NOTES:
- Abduction/Adduction of the fingers at the MCP joints are movement relative to an imaginary line through the middle of the middle finger when the middle finger is in anatomic position.
- The middle finger abducts in the frontal plane in both directions that it moves: radial abduction and ulnar abduction. The middle finger cannot adduct.
- Rheumatoid arthritis often manifests at the MCP joints with a characteristic ulnar deviation deformity.
Anterior view of the metacarpophalangeal joints on the right side of the body (as well as other joints of the wrist and hand).
Posterior view of the metacarpophalangeal joints on the right side of the body (as well as other joints of the wrist and hand).
Bones of the wrist and hand in the posture of a fist on the right side.
