The proximal phalanx of the thumb is immediately distal to the first metacarpal. In other words, the bone of the lower thumb connects to the first metcarpal.

The capitate bone.

The third metacarpal bone of a horse is called the cannon bone or shin bone. The canon bone is the major support bone of body weight.

Metacarpal bones

A common fracture of the fifth metacarpal bone of the hand is often referred to as the "Boxer's Fracture." The fifth metacarpal is the bone in the hand that attaches to the pinky finger.