Metacarpophalangeal joints

These joints connect the bones of the hand to the fingers, allowing for a wide range of motion.

Metacarpophalangeal joints, commonly known as MCP joints, are the hinge-like connections between each metacarpal bone in the hand and the proximal phalanges of the fingers. These joints are classified as synovial joints, allowing for both flexion and extension, as well as some degree of abduction and adduction of the fingers. Each joint is surrounded by a capsule, which contains synovial fluid that lubricates the joint and reduces friction during movement.

Terminologia Anatomica

articulatio metacarpophalangea

System

Skeletal system

Function

The primary function of the metacarpophalangeal joints is to facilitate the movement of the fingers, enabling actions such as grasping, typing, and gesturing. Flexion and extension at these joints allow the fingers to curl inward or stretch outward, while the ability to abduct and adduct means that the fingers can move apart or together. This versatility is essential for performing precise tasks as well as strong grips. The alignment and distribution of the metacarpophalangeal joints contribute significantly to the overall dexterity and functionality of the hand.

Location

Located at the base of each finger, the metacarpophalangeal joints sit between the five metacarpal bones of the palm and the proximal phalanges of the fingers. They are typically situated in a slightly elevated position relative to the palm, making them easily palpable. The first metacarpophalangeal joint, associated with the thumb, is located laterally compared to the other joints and exhibits a slightly different range of motion, crucial for thumb opposition. As a result, the MCP joints are strategically positioned to allow maximum movement while maintaining stability during gripping and manipulation.

Did You Know?

The thumb has a greater range of motion at its metacarpophalangeal joint compared to the other fingers, enabling the thumb's unique ability to oppose the other digits.
In total, there are ten metacarpophalangeal joints in each hand, as each of the five fingers has its own joint.
The health of the metacarpophalangeal joints is critical for maintaining hand function, with conditions like arthritis potentially leading to significant impairment.