Die Anatomie des Eintrittspunktes bei retrograder Femurmarknagelung

Background: Aim of the study was to evaluate the degree of damage of the articular cartilage and lesions of the femoral origin of the posterior cruciate ligament caused by the implantation of a retrograde intramedullary femoral nail. Methods: In 30 cadavers preserved according to Thiel's method and aged between 61 and 76 years (mean 64 years), retrograde femoral nailing was performed in both legs (n = 60) through a transligamentous approach using a DFN (distal femoral nail, Mathys-Synthes®). The procedure was radiologically controlled by an image intensifier. Subsequently, the knee joints (n = 60) were dissected and the entry point of the nail was evaluated anatomically and morphometrically. Results: Depending on the size of the joint, 7-15% of the patello-femoral articular surface (Facies articularis patellaris femoris) were destroyed by the implantation of the DFN. In none of the specimens, lesions of the PCL-origin were observed. Conclusion: Retrograde femoral nailing is a safe technique if lesions of the PCL are considered. Destruction of retropatellar articular cartilage due to the nail's diameter is relatively higher in small joints. However, the region of destruction is placed in the distal part of the patello-femoral joint, which is not exposed to extended loading during the gait circle.