Mega Prosthetic Knee Replacement For Treatment of Resistant Distal Femoral Non Union

The incidence of non-union in distal femoral fractures has been reported from 0 to 13%. Treatment of these fractures has always been challenging and there is still no established consensus on ideal treatment of nonunion of such fractures. Preservation of knee function and early weight bearing should be the objectives of management to have best clinical outcome. We report treatment of three cases of distal femoral fractures which had failed to unite despite prior internal fixation with a distal femoral tumor endoprosthesis (megaprosthesis) originally developed for use in musculoskeletal tumor surgery as a treatment option as an alternative to internal fixation. The Knee Society Score increased form 35 to 78 & Knee Society Function Score increased form 5 to 80 in these patients. Our patients had good range of motion (70-90 degree flexion) at 8 months of follow up and were walking pain free without the need of any ambulatory support. We thus conclude that cemented Megaprosthesis appears to be a viable one time treatment solution for failed internal fixation of distal femoral fractures, associated with distal femoral bone loss and secondary knee arthritis with or without ligamentous instability in elderly patients.