In the wrist, structure F corresponds to which carpal bone?

In the wrist, structure F corresponds to which carpal bone?

• A. Hamate
• B. Trapezium
• C. Trapezoid
• D. Capitate

Answer: (C)

In the wrist, the distal row of carpal bones runs from the thumb side to the little-finger side as: trapezium, trapezoid, capitate, hamate. The bone that sits between the trapezium and the capitate is the trapezoid, and it typically articulates with the base of the second metacarpal. On a radiograph or diagram, if structure F is the bone between the trapezium and the capitate and aligned with the second metacarpal, that identifies it as the trapezoid. The other bones have distinctive features: the trapezium almost always associates with the first metacarpal (the thumb) and has a saddle-shaped surface; the capitate is the largest distal bone near the center; the hamate has a hooked projection (hook of the hamate) on its palmar side. The trapezoid’s position and its articulation with the second metacarpal make it the best match for structure F.

In the wrist, the distal row of carpal bones runs from the thumb side to the little-finger side as: trapezium, trapezoid, capitate, hamate. The bone that sits between the trapezium and the capitate is the trapezoid, and it typically articulates with the base of the second metacarpal. On a radiograph or diagram, if structure F is the bone between the trapezium and the capitate and aligned with the second metacarpal, that identifies it as the trapezoid. The other bones have distinctive features: the trapezium almost always associates with the first metacarpal (the thumb) and has a saddle-shaped surface; the capitate is the largest distal bone near the center; the hamate has a hooked projection (hook of the hamate) on its palmar side. The trapezoid’s position and its articulation with the second metacarpal make it the best match for structure F.