In human anatomy, the metacarpal bones or metacarpus, form the intermediate part of the skeletal hand located between the phalanges of the fingers and the carpal bones of the wrist which forms the connection to the forearm. The metacarpal bones are analogous to the metatarsal bones in the foot.

The metacarpals form a transverse arch to which the rigid row of distal carpal bones are fixed. The peripheral metacarpals (those of the thumb and little finger) form the sides of the cup of the palmar gutter and as they are brought together they deepen this concavity. The index metacarpal is the most firmly fixed, while the thumb metacarpal articulates with the trapezium and acts independently from the others. The middle metacarpals are tightly united to the carpus by intrinsic interlocking bone elements at their bases. The ring metacarpal is somewhat more mobile while the fifth metacarpal is semi-independent.

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