Outcomes of Isolated Radial Osteotomy for Volar Distal Radioulnar Joint Instability Following Radial Malunion in Children.

PURPOSE: The radius bone has a slight dorsoradial bow that allows for full forearm pronosupination around the ulna. However, radial malunion can lead to reversal of the radial bow and subsequent volar instability of the distal radioulnar joint (DRUJ), predominantly in supination. This study assessed the outcomes of corrective radial osteotomy for volar DRUJ instability after radial malunion in children.

METHODS: The charts of 7 children (2 boys and 5 girls) treated with corrective radial osteotomy for volar DRUJ instability after a radius fracture or deformity were reviewed. Demographic, diagnostic, treatment, and complication information was collected for each patient. Radiographs at initial injury, fracture union, diagnosis of DRUJ instability, and final follow-up were reviewed for radiographic measurements of radial deformity and subsequent correction.

RESULTS: Fractures included 4 distal radius, 2 proximal radius, and 1 plastic deformation of the radial shaft. Volar DRUJ instability was diagnosed an average of 2.7 years (range, 1-6 years) after fracture at an average age of 13.6 years (range, 12-17 years). Two of 7 patients had persistent symptoms despite having undergone previous soft tissue surgery for DRUJ instability. Radial osteotomy was performed on all patients (3 dorsal and 4 volar approaches), with an average sagittal plane correction of 23° ± 10° (range, 14° to 40°). Osteotomy site varied (3 proximal third, 1 middle third, and 3 distal third) based on the apex of maximal deformity. Patients were observed an average of 2.3 years (range, 1.0-5.7 years). At final follow-up, all patients had a stable DRUJ and no patient required soft tissue stabilization.

CONCLUSIONS: Apex volar malunion of radial fractures may result in volar instability of the DRUJ. Radial osteotomy restored the normal apex dorsal radial bow and effectively stabilized the DRUJ without the need for soft tissue repair. Osteotomy should be tailored to the specific site of radiographic deformity.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.