Four different fixation strategies for ipsilateral femoral neck and shaft fractures: a finite element analysis.

BACKGROUND

Ipsilateral femoral neck and shaft fractures are complex injuries that result from high-energy trauma. Despite the availability of multiple fixation strategies, optimal surgical management remains a subject of ongoing debate and comparative biomechanical data are lacking. This study evaluated the stability of four commonly used constructs for internal fixation using patient-specific finite element analysis (FEA) to provide a robust biomechanical rationale for surgical decision-making.

METHODS

Patient-specific FEA models were reconstructed using computed tomography imaging data of eight patients to simulate a complex injury pattern involving an ipsilateral Pauwels type III femoral neck fracture combined with a comminuted femoral shaft fracture. Four distinct internal fixation strategies were evaluated: proximal femoral nail antirotation, compression plate with cannulated screws, antegrade intramedullary nail with cannulated screws (AN-CS), and long proximal femoral locking plate. Stability parameters were quantified under simulated axial and torsional loading conditions to assess the mechanical performance of each construct.

RESULTS

Under both loading conditions, the AN-CS group consistently maintained low levels of femoral and implant displacement while demonstrating a more uniform stress distribution and minimum interfragmentary motion at the femoral neck fracture site.

CONCLUSION

Of the four fixation methods evaluated in this simulation study, the AN-CS construct exhibited the best biomechanical performance overall. The AN-CS fixation effectively balanced interfragmentary stability with a uniform stress distribution, thereby providing a biomechanical basis to guide subsequent clinical decision-making.