SHPI ASIS Virtual Fill, IC, and commercial software virtual fill pelvic tracking mean RMSEs with error bars representing the respective first standard deviation for frontal and sagittal plane hip angles. RMSEs for SHPI ASIS Virtual Fill, IC, and commercial software virtual fill pelvic tracking sagittal plane hip angles were 2.3±0.9°, 6.9±1.8°, and 4.4±1.5°, respectively. For frontal plane hip angles, RMSE values were 0.8±0.2°, 0.9±0.3°, and 0.7±0.2°.