Comparison of corticocancellous bone graft from the anterolateral metaphysis of the distal radius versus iliac crest for the treatment of unstable scaphoid nonunion with humpback deformity

Abstract

Background: Corticocancellous bone grafting from the iliac crest is acceptable treatment for unstable scaphoid nonunion with a viable proximal pole. However, harvesting graft from the iliac crest is associated with donor site morbidity and the requirement of general anesthesia. Thus, bone grafting from the anterolateral metaphysis of the distal radius (DR) can be a treatment option. However, no study has compared the clinical effect between the two grafting techniques.

Methods: From 2014 to 2019, patients with unstable scaphoid nonunion with humpback deformity underwent corticocancellous bone grafting from the anterolateral metaphysis of the DR (group DR) or iliac crest (group IC). Humpback deformity was determined by evaluating the scapholunate angle (SLA) ≥ 60°, intrascaphoid angle (ISA) ≥ 45°, and radiolunate angle (RLA) ≥ 15° from preoperative radiographs and computed tomography scans. The SLA, ISA, and RLA served to gauge carpal alignment. The operative time, grip strength, active range of motion (ROM), the Modified Mayo Wrist score (MMWS), and Disabilities of Arm, Shoulder, and Hand (DASH) score were assessed postoperatively.

Results: Thirty-eight patients qualified for the study (group DR, 15; group IC, 23). Union rates did not differ by patient subset (group DR, 100%; group IC, 95.7%; P = .827), and grip strength, ROM, MWS, and DASH score were similar between groups at the last follow-up. The operative time (minutes) was significantly shorter in group DR (median, 98; quartiles, 80, 114) than in group IC (median, 125; quartiles, 105, 150, P < .001). The ISA, RLA, and SLA improved postoperatively in both groups (P < 0.001). The degree of restoring carpal alignment, as evaluated by SLA, showed superior correction capability in group DR (median, 25.3% quartiles, 21.1, 35.3, P < 0.05). Donor site complications were not significantly different between the groups.

Conclusions: Corticocancellous bone graft from the anterolateral metaphysis of the DR for unstable scaphoid nonunion is associated with a shorter operation time and comparable results with that from the iliac crest in regard to union, restoration of carpal alignment, and wrist function.

Level of evidence: Level III.