Capsulodesis for the treatment of chronic scapholunate instability.

PURPOSE: Scapholunate (SL) instability is the most common form of carpal instability. The treatment of this disorder is challenging and varying treatment options have been described. The purpose of this study was to examine the intermediate-term results of dorsal capsulodesis for cases of chronic SL dissociation.

METHODS: A retrospective analysis was conducted that examined all dorsal capsulodesis procedures performed for chronic SL dissociation between January of 1990 and February of 2000. Wrist pain had to be present for greater than 3 months. Patients had to have a minimum follow-up period of 2 years for inclusion in the study. Thirty-one patients were identified with isolated chronic SL dissociation. Of the 31 patients 18 had dynamic carpal instability and 13 had static carpal instability. The time from injury to surgery averaged 20 months. The follow-up period averaged 54 months (range, 24-96 mo). All patients had a dorsal capsulodesis procedure using either a Blatt or Mayo technique. Results were reviewed clinically and radiologically. Static and dynamic groups were compared with a Student t test.

RESULTS: There was a 20% decrease in wrist motion after capsulodesis. There was no improvement in grip strength after surgery. Most patients had improvement in pain but only 2 patients were completely pain free. Radiographically the SL gap increased over time from 2.7 mm before surgery to 3.9 mm at the final follow-up evaluation. The SL angle also increased from 56 degrees before surgery to 62 degrees on final follow-up evaluation. There was no statistical difference in overall wrist motion, grip strength, or wrist score between the dynamic and static groups. The time to surgery and age had no significant effect on overall outcome.

CONCLUSIONS: Dorsal capsulodesis provided pain relief for patients with both dynamic and static SL instability. Although pain was improved it was not completely resolved in the majority of cases. From a radiographic perspective dorsal capsulodesis did not provide maintenance of carpal alignment in cases of chronic SL dissociation.