Acromioclavicular joint osteoarthritis, prevalent among middle-aged and older adults, leads to shoulder pain and functional limitations. Addressing inconsistencies in physical diagnosis, this study evaluated muscle forces during cross body adduction (CBA) and hand behind the back (HBB) tests using OpenSim and AnyBody Modeling System™. The study revealed both agreements and significant discrepancies in muscle force predictions between the two software by redefining joint kinematics and performing inverse dynamics analysis with generic upper extremity models. The findings highlight the need for integrating multiple modeling approaches and comprehensive validation with experimental data to improve accuracy and reliability in shoulder biomechanics assessments.
Note: 1st Image - CBA Test & 2nd Image - HBB Test. || Left - AnyBody & Top - HBB