Endosteal substitution with medial plate in the treatment of acute distal femur fracture (AO/OTA type A): surgical technique and case-series

Introduction Distal Femur fractures account for 4– 6% of all femur fractures and can be challenging to treat. The aims of this study are: (1) to describe a surgical technique using a medial distal femur endosteal plate to augment the stability of standard lateral plate fixation; (2) to report the results of a case-series of acute distal femur fractures (AO/OTA Type A/ Vancouver periprosthetic fractures Type C) treated using this technique. Methods This study describes the surgical steps for placement of a medial endosteal plate in combination with lateral locking plate in a cadaver model using fluoroscopy guidance. In addition, a retrospective database chart review for all patients with acute distal femur fractures treated with this technique over the last five years was performed. Exclusion criteria were involvement of type B and C distal femur intraarticular fractures, treatment with other endosteal substitutions (i.e., intramedullary nail fixation and fibula allograft), and treatment for non-union or pathological fractures. Results Twelve patients were identified with mean age of 75 years. All patients were female and all of them were allowed full weight bearing and full range of motion exercises immediately post-operatively. The complete follow up for one patient was not available; however, the mean fracture union was confirmed at 3.8 months in 10 of 12 patients. One patient had a failed construct at three months in the context of a periprosthetic fracture with a loose implant that was initially thought to be stable. One acute superficial surgical site infection was reported and healed uneventfully following debridement, primary closure, and antibiotic treatment. Conclusion We believe that the placement of a medial endosteal plate can be a useful augment for standard lateral plate fixation in acute distal femur fractures, particularly in the context of severe comminution or poor bone quality. Uneventful healing was confirmed in 10 of 12 cases and no patients were restricted with regard to motion or weight bearing immediately post-operatively. Further studies with larger sample size would be required to fully assess this technique. Level of evidence IV. Therapeutic Study (Surgical technique and Cases-series).