Definition

1. Noun:
   • Anatomy: The metacarpophalangeal joint is the knuckle joint of the hand, located between the metacarpal bones of the palm and the proximal phalanges of the fingers. It is a condyloid joint that allows for flexion, extension, abduction, and adduction.

Usage

• The metacarpophalangeal joint is crucial for gripping and fine motor control of the hand.
• Arthritis commonly affects the metacarpophalangeal joint, causing pain and stiffness in the knuckles.
• A boxer's fracture typically involves the neck of the metacarpal bone just behind the metacarpophalangeal joint.

Advanced Usage

• Clinical/Medical Context: The term is primarily used in technical, anatomical, and medical descriptions. It is often abbreviated as MCP joint in clinical notes and discussions.
  • The patient has reduced range of motion in the second and third metacarpophalangeal joints.
• Plural Form: The plural is metacarpophalangeal joints.

Variants and Related Words

• MCP joint (n.): The standard abbreviation for metacarpophalangeal joint.
• Knuckle (n.): The common, non-technical term for the metacarpophalangeal joint, especially when the fist is clenched.
• Interphalangeal joint (n.): The finger joint located to (beyond) the metacarpophalangeal joint, between the phalangeal bones.

Synonyms

• Knuckle (in common, non-technical usage)
• MCP joint (abbreviation)

Notes on Meaning

• The reference context "a joint of a finger when the fist is closed" accurately describes the visible and functional aspect of the metacarpophalangeal joint. When making a fist, these joints form the prominent knuckles.

Noun

1. a joint of a finger when the fist is closed