Can Lateral Offset Be Used as a Predictive Marker for Proximal Femur Disorders?

Purpose: When the lateral offset (LO) changes, the forces acting on the head and neck of the femur change. Increase or decrease in LO can cause instability and possible dislocation of the implant. In addition, when the offset is reduced, more force is needed to balance the pelvis by the abductor muscles, and the force that occurs along the hip joint increases and causes wear and tear. In this study we aimed to investigate whether there is a correlation between LO and proximal femur morphology, and according to the results we aimed to investigate whether the LO can be used as a predictive marker for the risk of femoral neck fractures, osteoarthritis or femoroacetabular impingement.
Methods: Femur length, femur neck length, femoral neck-shaft angle (NSA), anteroposterior (a-p) and superoinferior (s-i) diameters of femoral head and neck, and LO were measured on 82 dry adult femora of unknown age and gender from Turkish population.
Results: There was no statistically significant correlation between the LO and a-p and s-i diameters of femoral head or neck. However, there was found statistically significant correlation between LO and femoral NSA (p < 0.01), femoral neck length (p < 0.05) and femur length (p < 0.01).
Conclusion: High LO values can be used as an indicator for neck fractures, a negative marker for OA, but LO does not appear to be used as an indicator for FAI. © Indian Orthopaedics Association 2021.