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.