Relationship between wrist motion and capitolunate reduction in four-corner arthrodesis

The authors retrospectively studied 36 patients with degenerative changes associated with scaphoid nonunion and scapholunate advanced collapse treated with circular plate fixation and bone graft. The goals of the study were to review the incidence of dorsal impingement, nonunion of arthrodesis, loose hardware, broken screws, and limitation in wrist motion associated with correct or incorrect surgical capitolunate reduction. Surgical indications were scapholunate advanced collapse (3 patients), scaphoid nonunion advanced collapse (32 patients), and sequelae of irreducible perilunate dislocation (1 patient). All of the patients were men, with a mean age of 48 years (range, 35-68 years). Average follow-up was 56 months (range, 12-108 months). Functional outcomes evaluated were pain with the visual analog scale, range of motion, grip strength, Disabilities of the Arm, Shoulder and Hand (DASH) score, satisfaction, and time to union. Mean visual analog scale score was 7 (range, 5-9) preoperatively and 1 (range, 0-2) postoperatively. Average wrist range of motion was 42° in extension, 36° in flexion, 15° in ulnar deviation, and 12° in radial deviation. Mean grip strength was 34 kg preoperatively, 50 kg postoperatively, and 56 kg contralaterally. Thirty-five of the 36 patients achieved union at 6 months. Degenerative changes at the radiolunate articulation were present in 1 patient 62 months after surgery, but he was asymptomatic. Mean capitolunate angle was 38 preoperatively and 9 postoperatively. Poor correlation was found between the measured capitate-lunate angle and subsequent flexion and extension (r=0.32 and r=0.17, respectively) using the Pearson correlation coefficient. The authors noted 1 or 2 broken screws in 3 cases (8.3%) and hardware dorsal impingement in the plate in 6 cases (16.6%). Mean DASH score was 24 of 100. Overall patient satisfaction was 70%.