Reverse Total Shoulder Arthroplasty (rTSA) is becoming a popular surgery to alleviate pain caused by massive rotator cuff damage and shoulder arthritis. However, due to the reversed anatomy, the loads on the muscles within the shoulder are not well known. The Musculoskeletal Institute at UConn Health is currently researching rTSA using a cadaveric shoulder simulator, but the deltoid muscle is not simulated in a way that is accurate to the human anatomy. To shed light on this new anatomy, our team is designing a device that is capable of being installed on the shoulder simulator that will replicate the contraction of the deltoid muscle in the simulator, pulling on both the origin of the deltoid on the acromion, and the insertion of the deltoid on the humerus. The team is involved in the actual trials and testing process which will include data from both native and rTSA implanted shoulders. AnyBody software is also used to model the forces of the deltoid muscle fibers to ensure correct physical modeling.