A metacarpal bone may fracture at the base, shaft or neck as a result of a direct blow, a fall upon the hand, or from the longitudinal force transmitted when punching with a closed fist. The fifth metacarpal is most commonly affected, often in isolation, as in the classical fifth metacarpal neck fracture seen in boxer's.
The main concern is with residual rotational deformity as this may make closure of the hand into a fist impossible without the affected finger overlapping one of it's neighbours. Subsequent osteotomy may then be required.
Angular deformity is often minor and even if it persists, rarely impairs function.
The first metacarpal may be broken into the carpometacarpal joint to produce a Bennett's fracture subluxation.
Last reviewed 01/2018