Z-Corrective Osteotomy in Malunited Extra-Articular Fractures of Distal Radius

Abstract

We sought to assess clinical, radiological, and functional outcomes following treatment of extra-articular malunions of the distal radius using a multiplanar z-corrective osteotomy. Fifteen patients with extra-articular distal radius malunions (13 dorsal and 2 volar) underwent z-corrective osteotomy and volar plate fixation without bone grafting. Correction and maintenance of each deformity was evaluated in terms of various radiographic indices (radial height; volar and radial tilt); osteotomy union; pain (visual analog scale); grip strength; range of motion; Disabilities of the Arm, Shoulder, and Hand scores; and Mayo wrist scores. The mean follow-up was 16.4 months. The mean radial height was corrected from -1.3 mm to 4.9 mm. The mean ulnar variance improved from 4.3 mm to -0.4 mm. The sagittal radial tilt and radial inclination were restored from a mean of -17.9° (dorsal) to 3.3° (volar) and from 12.0° to 17.2°, respectively. The Disabilities of the Arm, Shoulder, and Hand and Mayo wrist scores improved from means of 36 and 56 preoperatively to 24.8 and 73.3, respectively, at 6 months and further to 20.6 and 77.6, respectively, at the last follow-up. There were no nonunions or tendon-related problems. The mean pain score decreased from 4.1 preoperatively to 1.0 at 6 months and 0.8 at the last follow-up. The mean grip strength improved from 5.6 kg preoperatively to 15.6 kg at 6 months and 19.7 kg at the last follow-up. There was a statistically significant improvement in range of motion at the wrist. The z-osteotomy provides correction of deformity in all 3 planes, along with restoration of radial height. It also maintains a broad area of bone contact between the 2 osteotomized bone fragments, facilitating bony union and eliminating the need for bone grafting. Therapeutic IV.