Dislocated 4th and 5th carpometacarpal joints


These dislocations may be associated with small intra-articular fractures of the metacarpal heads or adjacent carpals which may be occult on x-ray, and therefore CT is often performed after relocation.

On the AP view only, the dislocations may be missed and in the viva exam setting the examiner may withhold the lateral until the candidate comments on the shortening of the 4th metacarpal and malalignment of the 4th and 5th carpometacarpal joints on the AP view.