Which joint is formed between the metacarpal and a proximal phalanx?

Which joint is formed between the metacarpal and a proximal phalanx?

• A. Metacarpophalangeal joint
• B. Interphalangeal joint
• C. Radiocarpal joint
• D. Carpometacarpal joint

Answer: (A)

The joint formed between a metacarpal and a proximal phalanx is the metacarpophalangeal joint. This is the knuckle area at the base of each finger, where the rounded head of the metacarpal meets the base of the proximal phalanx. It’s a condyloid joint, meaning it allows flexion and extension of the finger, and to a lesser extent some sideways movement (abduction/adduction) and circumduction. This differentiates it from other hand joints: interphalangeal joints occur between phalanges themselves (proximal with middle, and middle with distal), radiocarpal joints form the wrist between the radius and the carpal bones, and carpometacarpal joints connect the carpal bones to the metacarpal bases.

The joint formed between a metacarpal and a proximal phalanx is the metacarpophalangeal joint. This is the knuckle area at the base of each finger, where the rounded head of the metacarpal meets the base of the proximal phalanx. It’s a condyloid joint, meaning it allows flexion and extension of the finger, and to a lesser extent some sideways movement (abduction/adduction) and circumduction. This differentiates it from other hand joints: interphalangeal joints occur between phalanges themselves (proximal with middle, and middle with distal), radiocarpal joints form the wrist between the radius and the carpal bones, and carpometacarpal joints connect the carpal bones to the metacarpal bases.