Distal capitate shortening with capitometacarpal fusion for management of the early stages of Kienbock's disease with neutral ulnar variance: case series

Background: The aim of surgical management of Kienbock's disease has been proposed to slow the progressive osteonecrosis and secondary carpal damage. The aim of this case series was to evaluate the results of a new technique, combining distal capitate shortening with capitometacarpal fusion for the treatment of Kienbock's disease (Lichtman stage II or stage IIIA) in neutral ulnar variance patients. Methods: From 2009 to 2012, 12 patients (mean age: 25 +/- 7.6 years) were enrolled in this series. Radiological and clinical evaluations using the modified Mayo wrist scoring system were performed both pre-operatively and 12 months post-operatively. In addition, values of the scapho-capitate angle were evaluated both pre-operatively and 12 months post-operatively. The mean follow-up was 20.7 +/- 11.2 months. Statistical analysis was performed for comparisons between pre-operative and post-operative findings with the use of paired sample T test, Pearson's correlation, independent sample T test, and Spearman's rho correlation. Statistical significance was determined to be present at p < 0.05. Results: All patients achieved bony union at the fusion site within a mean period of 11.5 +/- 2.4 weeks. Regarding wrist pain, grip strength, total wrist arc of motion, practicing daily activities in a normal pattern, and the total modified Mayo wrist score, there were statistically significant differences between the pre-operative and post-operative results. For the differential arc of motion, the only non-significant results were at the ulnar/radial deviation range (p = 0.262). The mean pre-operative scapho-capitate angle was 29.75 +/- 3.44 while the mean post-operative value was 33.67 +/- 4.77 (p < 0.001). Both pre-operative and post-operative scapho-capitate angle values were positively correlated to post-operative pain, ulnar/radial deviation, and final score (p = 0.001, 0.027, 0.021 and p = 0.001, 0.004, 0.002, respectively). Other parameters had no correlation to this angle. Post-operative MRI (at 12 months follow-up) demonstrated better lunate revascularization in four patients; one of them was diagnosed as having Lichtman stage IIIA Kienbock's disease. There were no patient-reported complications at the end of follow-up. Conclusions: Distal capitate shortening combined with capitometacarpal fusion represents a new reliable method in the treatment of early stages of Kienbock's disease with neutral ulnar variance.