Assessment of a greater trochanter-based method of locating the hip joint center.

An alternative, yet unverified, predictive method that places the hip joint center (HJC) at one-quarter of the distance from the ipsolateral to the contralateral greater trochanter (GT method) is currently widely used in the biomechanics community. Therefore, the objective of this study was to confirm that this method is a viable option for estimating HJC coordinates. To accomplish this, HJC coordinates in the pelvic anatomical coordinate system were estimated via the GT method, a functional method, and the regression equations proposed by Bell et al. (1990). The HJC coordinated estimated by the functional method served as a baseline measurement. The results of this study demonstrate that all three methods evaluated offer repeatable estimates of HJC location. In comparison to the functional method, the GT method yielded a HJC estimate that was 7.6mm medial, 12.2mm posterior, and 4.8mm proximal. On the other hand, the Bell regression equations estimated the HJC to be 2.6mm medial, 7.2mm posterior, and 21.7mm proximal relative to the functional method. Additionally, the total 3D difference between the GT and functional methods was 23.5mm compared to the 30.8mm difference between the Bell and functional methods. These results suggest that the GT method is a viable option for estimating HJC coordinates.