The shoulder provides mobility to the upper limb and is thus necessary for lots of activities. Consequently injuries in the shoulder joint affect the patient in his daily life. The study of shoulder pathologies is however difficult : each patient has his individual anatomy and his own lifestyle which have an impact on his shoulder biomechanical pattern. This is why patient specific shoulder models are necessary to explore precise and specific features of the patient’s shoulder joint. The goal of this project was to analyse the impact of individual anatomy on the shoulder muscle coordination. To do this, we built two patient specific musculoskeletal models. The first one was based on MRI scans of a male volunteer, the second one on MRI scans of a female volunteer. We observed both models to predict similar muscle force patterns and joint reaction forces. However, the models predicted variations in muscle force intensity, that were related to the anatomic changes.