Corrective osteotomy of malunited distal radius fractures using carbonated hydroxyapatite as an alternative to autogenous bone grafting.

PURPOSE: The purpose of the present study was to report on the author's experience using carbonated hydroxyapatite as a bony substitute in distal radius corrective osteotomies.

METHODS: Six patients had a corrective osteotomy for a malunited distal radius fracture using carbonated hydroxyapatite as an alternative to an autogenous bone graft. Internal fixation of the osteotomy was achieved by using 2 or 3 K-wires.

RESULTS: At an average follow-up evaluation of 33 months (range, 22-45 mo) all the osteotomies united. Wrist flexion-extension motion improved from 75 degrees to 110 degrees , forearm rotation increased from 116 degrees to 157 degrees , and grip strength had an average increase of 140% at the time of the final follow-up evaluation. All patients were satisfied and there were no reports of persistent pain. Radiographic evaluation showed an average volar tilt improvement from a preoperative dorsal angulation shifting into a neutral position in the sagittal plane; radial lengthening improved from an average of 4 mm (range, 2-6 mm) before surgery to 7 mm (range, 5-9 mm) after surgery, ulnar plus deformity improved by 5 mm. Radiographically the carbonated hydroxyapatite material was integrated completely into the bone tissue with evidence of progressive re-absorption and bony calcification over time. The Mayo wrist score system, according to Cooney and Krimmer modifications, improved by an average of 88 and 98 points (0-100 points), respectively.

CONCLUSIONS: On the basis of this preliminary experience it is reasonable to consider carbonated hydroxyapatite as a viable alternative to bone grafting in conjunction with surgical correction of a distal radius malunion. It must be augmented, however, with internal fixation.