3-Dimensional prebent plate fixation in corrective osteotomy of malunited upper extremity fractures using a real-sized plastic bone model prepared by preoperative computer simulation.

Abstract

To assess the clinical outcome and accuracy of prebent plate fixation in corrective osteotomy for malunited upper extremity fractures using a plastic bone model manufactured by preoperative computer simulation. Nine consecutive patients underwent computed tomography (CT)-based 3-dimensional corrective osteotomy for malunited upper extremity fractures. There were 4 cubitus varus deformities, 1 cubitus valgus deformity, and 4 forearm diaphyseal malunions. We constructed a computer model of the affected bones using the CT data and simulated the 3-dimensional deformity correction on a computer. A real-sized plastic model of the corrected bone was manufactured by rapid prototyping. We used a metal plate, prebent to fit the plastic bone model, in the actual surgery. Patients were evaluated after an average follow-up of 22 months (range, 14-36 mo). We retrospectively collected radiographic and clinical data at the most recent follow-up and compared them with preoperative data. We also performed CT after surgery and evaluated the error in corrective osteotomy as the difference between preoperative simulation and postoperative bone model. The range of forearm rotation and grip strength in patients with forearm malunions improved after corrective osteotomies of the radius and ulna. Wrist pain, which 2 patients with forearm malunion had experienced before surgery, disappeared or decreased substantially after surgery. Radiographic examination indicated that preoperative angular deformities were nearly nonexistent after all corrective osteotomies. Three-dimensional errors in the corrective osteotomy using a prebent plate, as evaluated by CT data, were less than 3 mm and 2°. Prebent plate fixation in corrective osteotomy for malunited upper extremity fractures using a 3-dimensionally corrected, real-sized plastic bone model prepared by preoperative computer simulation is a precise and relatively easily performed technique that results in satisfactory clinical outcome. Therapeutic IV.