Imaging Case of the Week 512 Answer

The frontal wrist x-ray shows loss of normal 1-2 mm distance between the the carpal bones and there is crowding of carpal space at the base of 4th & 5th metacarpal bases.

The lateral wrist x-ray shows a chip of bone dorsal to the distal carpal row and this indicates presence of hamate fracture. There is also posterior displacement of the bases of 4th & 5th metacarpals.

Carpometacarpal dislocations can be difficult to spot and high index of suspicion is needed. All such cases should be referred to hand surgeon from the ED.