Development of an intraoperative 3D C-arm technique for torsion control of femur fractures: a cadaver study

Aim This study aims to test the accuracy and feasibility of a measurement of femoral torsion of a 3D C-arm system (Linea aspera method) in a cadaver setting. Materials and methods A total of 11 intact femora were used. Schanz screws were inserted in the femoral bone in a parallel manner with the help of a fixed drill sleeve. Femur bones were then fractured in a controlled manner and three different internal and external torsion angles were fixed with the help of a Goniometer. After that, a 3D scan was performed. The 3D data set was analyzed using a radiologic software (Visage 7, Visage Imaging Inc, USA). Measurements were then compared in the two methods with a dependent t test. Results Specific measurements for different angles did not show any differences between those two utilities. Conclusion Intraoperative estimation of femoral antetorsion using a 3D C-Arm system and the Linea aspera method seems to be an accurate and feasible method. Nevertheless, more studies with higher patient numbers, comparison to CT seems to be the next step and can be recommended.