The Full Body Model (https://simtk.org/projects/full_body) of Rajagopal et al. (2016) compatible with OpenSim v4.1 was adjusted to contain all 22 hip spanning muscles. Six hip spanning muscles (obturator internus, obturator externus, quadratus femoris, gemellus inferior, and gemellus superior, pectineus) were added and two muscle paths (posterior gluteus medius and piriformis) were adjusted. As per Rajagopals study (Rajagopal et al., 2016), muscle volumes of the added muscles were calculated for a 75kg, 170cm tall male via Hansfields equations (Handsfield et al., 2014) using a specific muscle tension of 60N/cm2.

For more details regarding the model adjustments, see: https://doi.org/10.1109/tbme.2021.3114717