Abstract
Radiological and clinical evaluations were carried out on 67 rhematoid wrists in 53 patients who were treated by synovectomy of the extensor sheath and the wrist joint combined with Darrach's procedure in the period from 1966 to 1986 in the authors' orthopaedic department. Based on preoperative X-ray findings, 14 wrists in 12 cases were classified into grade I or II according to Larsen's classification, hence into the group of early synovectomy, and the other 53 wrists in 41 cases were classified into grade III or more, hence into the group of late synovectomy. The follow-up period after the surgery was 10.1±6.4 years (mean±S.D.) in the former group, and 8.2 ±5.5 years in the latter. There was no significant difference in results between the two groups.
In the radiological follow-up, the degree of carpal collapse in the operated-on wrists was the same as in the opposite, non-operated-on rheumatoid wrists. However, ulnar shift of the carpus was significantly accelerated in wrists that received on operation combined with Darrach's procedure in which two years or more had elapsed (p≤0.01) . Volar subluxation of the carpus was negligible both in the operated-on and in the non-operated-on rheumatoid wrists.
In the group of early synovectomy, the progress of carpal collapse was slower than in the late synovectomy group. However, that of ulnar shift was more rapid, so that it is thought that either reconstruction of the triangular fibrocartilage complex in sufficient tension or radiolunate limited fusion is necessary, combined with Darrach's procedure, to prevent progress of ulnar shift.
In the late synovectomy group, the progress of ulnar shift was more slow and the postoperative improvement of function was steady, especially in regard to pain relief, suppression of the recurrent synovitis, and the continuous improvement of forearm rotation.
In conclusion, the synovectomy for the rheumatoid wrist, combined with Darrach's procedure, is worthwhile not only in the early stage, but also in the late stage, in combination with preventive measures against progressive ulnar shift of the carpus, except in cases of mutilans type.
