Pressure mapping of the radioulnar carpal joint: Effect of ulnar lengthening and wrist position

The purpose of this study was to investigate the effects of ulnar lengthening and wrist position on force transmission through the radioulnar carpal joint in a forced dorsiflexed wrist position, Eight cadaveric arms were subjected to a 30 kg compressive load directed down the forearm towards the wrist, A pressure sensor recorded forces across the wrist joint with the triangular fibrocartilage complex intact and excised. The biomechanics of the distal radioulnar joint were altered bg changes in ulnar length and wrist position. Pressures at the ulnolunate articulation increased as the ulna was lengthened and were significantly lower when the triangular fibrocartilage complex,vas excised, An inverse relationship between triangular fibrocartilage complex thickness and ulnar variance was shown. Greater increases in ulnolunate pressure were observed in more positive ulnar variant wrists.