Treatment of distal femur aseptic nonunion after lateral locking plate fixation: Results of medial custom made plating and free fibula flap transfer using CAD-CAM technology

Background: Aim of the present paper is to report the preliminary results of CAD-CAM (Computer-Aided Design - Computer-Aided Manufacturing) technology application to distal femur nonunion treatment with free fibula flap, custom made medial plating and maintenance of a stable lateral locking plate. Methods: Two cases of distal femur nonunion that occurred after lateral locking plating were treated and prospectively followed-up. Surgical planning followed the same preoperative protocol adopted for mandibular CAD-CAM reconstruction. Wide cutting sections were planned to obtain radical debridement. The tailored custom-made plate, a 3D rendering of bone defect and the cutting guides were produced and sterilized. Surgical intervention was conducted by steps (medial approach, bone resection, recipient vessels isolation, fibula harvesting and cutting, plate-fibula construct assembly, microvascular anastomosis, final fixation). Results: The mean follow-up was 13 (12–15) months. Bone union was achieved in both cases at mean 3.1 months. Full weight bearing without referred pain or discomfort was reached in both cases at mean 8,5 months (range 7–10). No complications occurred. Conclusions: CAD-CAM technology proved to be useful and reliable in custom made medial plating combined with free fibula transfer for the treatment of distal femur nonunion after lateral locking plating. Trial registration: none.