CARPAL INSTABILITY IN THE WEIGHT-BEARING UPPER EXTREMITY

The prevalence of carpal instability in a paraplegic population was in vestigated to establish an association between chronic repetitive stre ss on the wrist and the development of such instability. Nine of 162 p araplegic patients had static carpal instability and no history of an acute injury of the wrist. The predominant pattern of instability, fou nd in eleven wrists (six patients), was non-dissociative volar interca lated segmental instability. The prevalence of carpal instability incr eased with the duration of weight-bearing on the upper extremity. Eigh teen per cent of the patients in whom the spinal cord injury had occur red more than twenty years before the study had carpal instability. Ca rpal instability in these weight-bearing upper extremities and the inc rease in its prevalence with the duration of the forces across the wri st demonstrate an association between chronic repetitive stress on the wrist and carpal instability.