Metacarpophalangeal joint

Metacarpophalangeal joint
Metacarpophalangeal articulation and articulations of digit. Volar aspect.
Metacarpophalangeal articulation and articulations of digit. Ulnar aspect.
Latin	articulationes metacarpophalangeae
Gray's	subject #90 332
MeSH	Metacarpophalangeal+Joint

The metacarpophalangeal joints (MCP) are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the first phalanges, with the exception of that of the thumb, which presents more of the characters of a ginglymoid joint^[1]. Arthritis of the MCP is a distinguishing feature of Rheumatoid Arthritis, as opposed to the distal interphalangeal joint in osteoarthritis.

Ligaments

Each joint has:

• palmar ligaments of metacarpophalangeal articulations
• collateral ligaments of metacarpophalangeal articulations

Dorsal surfaces

The dorsal surfaces of these joints are covered by the expansions of the Extensor tendons, together with some loose areolar tissue which connects the deep surfaces of the tendons to the bones.

Movements

The movements which occur in these joints are flexion, extension, adduction, abduction, and circumduction; the movements of abduction and adduction are very limited, and cannot be performed while the fingers form a fist. ^[1]

The muscles of flexion and extension are as follows:

Location	Flexion	Extension
fingers	Flexor digitorum superficialis and profundus, lumbricales, and interossei, assisted in the case of the little finger by the flexor digiti minimi brevis	extensor digitorum communis, extensor indicis proprius, and extensor digiti minimi muscle
thumb	flexores pollicis longus and brevis	extensores pollicis longus and brevis

References

1. ^ ^{a b} Gray's Anatomy (1918), see infobox

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.

External links

• Hand kinesiology at UK bone/mpartic.html
• EatonHand joi-047
• Metacarpophalangeal+joint at eMedicine Dictionary