Reverse Bennett’s Fracture

The fracture-dislocation at the base of the fifth metacarpal is analogous to Bennett's fracture of the thumb (Fig. 13-1 A). Because of the obliquity of the fracture line, the obliquity of the metacarpal hamate joint, and the pull of the extensor carpi ulnaris, this fracture-dislocation tends to be unstable and to displace, much in the same fashion as the first metacarpal in a Bennett's fracture and with similar functional impairment.