The intricate interplay within the musculoskeletal system is crucial in biomechanics and orthopedics, particularly in animal locomotion. Conventional musculoskeletal models often oversimplify muscles as mere connections between skeletal points, disregarding radial variations during muscle contraction or relaxation that impact the surrounding tissues. Furthermore, animal movement is driven not solely by skeletal and muscular elements but also by complex, nonlinear attributes of soft tissues such as superficial fascia. These intricacies pose challenges for conventional models. A freely operable musculoskeletal robot employing Pneumatic Artificial Muscles (PAMs) was developed as a physical simulator, replicating the canine hindlimb structure and unveiling the effect of fascia in movement to address this issue. This robot’s potential applications extend to enhance the treatment of orthopedic disorders.