Patient specific instrumentation for corrective osteotomy in case of posttraumatic cubitus varus in children.

Malunion in cubitus varus results most often from inadequate supracondylar fracture reduction or from secondary displacement. Treatment of cubitus varus needs an accurate preoperative planning to obtain a good functional and esthetical outcome. Planning based on conventional radiology is source of inaccuracy and clinical results are variable. Developments of computer-assisted orthopaedic surgery (CAOS) and of patient specific instruments (PSI) have made accurate three dimensional (3D) preoperative simulation possible. This original technique based on 3D-osteotomy planning and using PSI was developed to correct cubitus varus deformity in the three dimensions. Results: At the latest follow-up, the correction of cubitus varus obtained was satisfying in the five cases of our series and all the patients had pain free elbow mobility. Ulnar nerve palsy complicated the evolution by one patient, which fully recovered within 6 months. Conclusions: Advantages of this technique include a decreased operating time and a smaller surgical incision. Moreover, results showed increased correction accuracy without the need of fluoroscopy during the osteotomy procedure. These benefits are counterbalanced by the need of a preoperative CT-scan of the distal humerus and the additional cost for the PSI.