Novel method for intra-operative computation of the femoral neck anteversion angle

摘要

Introduction: The clinical function of femoral neck anteversion affects in- or out-toeing, dislocation, range of motion, soft tissue strain, bone mineral density and bone shape, femoral stress, contact force, and osteolysis [1]. However, no method has been established as a gold standard to measure the femoral neck anteversion for the pre-planning of total hip replacement (THR) surgery in order to optimize planning and surgical correction through stem implantation. The use of a modular femoral neck and head system is one method of achieving predetermined anteversion and of adjusting offset and abductor lever arm [2]. To this end, we propose a robust and repeatable measurement method of femoral neck anteversion in terms of defining the femoral neck axis (FNA) and the posterior femoral plane (PFP) including the posterior condylar axis (PCA). The method allows intra-operative definition of the femoral reference system and of the femoral anatomical angles based on the acquired surface points.