The high degree of computational resources required to simulate finite element human body models has prompted the implementation of a method that incorporates detailed components into a simplified model. Previous studies have demonstrated this ability by incorporating the GHBMC M50‐O brain model into the simplified model (GHBMC M50‐OS+B), which allowed for localised analysis of the brain at a substantially reduced computational cost. We expand on this concept through the modular incorporation of detailed thoracoabdominal organs into the simplified model (M50‐OS+O), comparing force‐deflection and organ level response through an array of validation tests. This consisted of a frontal thoracic hub, oblique hub, abdominal bar, and frontal sled simulation. Organ response metrics included 95th percentile strain, internal energy, and organ kinematics and were compared between the M50‐O and the M50‐OS+O. Generally, the M50‐OS+O was able to capture the response of the M50‐O in both force‐deflection and organ level response, but in one‐tenth of the time.