Ulnocarpal translation in perilunate dislocations.

The purpose of this study was to assess ulnar translation in perilunate dislocation injuries. Twenty-five patients with perilunate dislocations were assessed after surgical reduction. Ulnar translation of the carpus and carpal collapse were measured using standard methods. Measurements before and after pin removal were compared. The average Gilula score for ulnar translation was 54%. Eighty percent of patients had ulnocarpal translation (above 50% of lunate uncovering) after reduction. Measurements of lunate uncovering in perilunate dislocations were significantly higher than normal values (P<0.01). Scores for patients in whom the ulnar translocation component was addressed by pinning during initial treatment were significantly improved. Measurements before and after pin removal were not significantly different irrespective of the method of measurement. IRB approval was obtained prior to study preparation.