In vivo measurement of distal radioulnar translation following distal radius fracture.

The incidence of distal radioulnar joint instability following a distal radius fracture is estimated around one in three based upon clinical examination. Using a validated rig, we objectively measured distal radioulnar joint translation in vivo following distal radius fracture. Dorsopalmar translation of the distal radioulnar joint was measured in 50 adults with previous distal radius fractures. Measurements were compared with the uninjured wrist and against a database of previous measurements within healthy and clinically lax populations. Translation at the distal radioulnar joint was greater in injured wrists at 12.2 mm (range 10-15, SD 1.2) than the uninjured wrists at 6.4 (range 4-9, SD 0.8) (p < 0.001) and was always outside the established normal range. There was no statistically significant link between translation and the severity of the injury. Instability appears almost inevitable following a distal radius (wrist) fracture, albeit subclinical in the vast majority.