Capitolunate versus Four-Corner Arthrodesis for Midcarpal Arthrosis.

Midcarpal fusion is a procedure indicated for midcarpal arthrosis or instability, though the merits of fusing the triquetrohamate joint in addition to the capitolunate joint are not known. The purpose of this study was to compare capitolunate fusion with four-corner fusion with a null hypothesis that no differences would exist in outcomes.  A retrospective chart review of patients with midcarpal arthrosis who underwent midcarpal fusion between the years 2013 and 2023 was conducted. Patients were separated into groups according to fusion type. Demographics and methods of fixation were recorded. Outcomes evaluated included subjective outcomes, radiographic alignment, success of fusion, range of motion, strength, and complications.  In total, 51 patients met inclusion criteria. Of these, 20 had capitolunate fusions and 31 had four-corner fusions. Staples were the most common form of fixation. Postoperative strength and range of motion were relatively preserved from preoperative levels in both groups. Both groups also had similar improvements in Disabilities of Arm, Shoulder, and Hand score. Capitolunate angles were not significantly different between groups; however, ulnar translocation was greater in the four-corner fusion group. Revision surgery was required in 10% of capitolunate fusions versus 29% of four-corner fusions, although this difference was not calculated to be significantly different.  Capitolunate fusion and four-corner fusion yielded comparable improvements with respect to clinical and radiographic outcomes. Fusing the triquetrohamate joint does not appear to enhance outcomes.