This study will evaluate the subscapularis repair versus non-repair during a reverse shoulder arthroplasty (RSA).

The primary objective of this study is to evaluate pain and function in patients undergoing RSA with or without subscapularis repair. This primary outcome will be measured by analysis of Constant scores at two years post-operative.

Secondary objectives are to evaluate pain, function and imaging, between the two groups at each applicable time point.

Inclusion Criteria:

1. Patient is scheduled to undergo a reverse shoulder arthroplasty procedure using the Arthrex ReversTM system.
2. Patient voluntarily consents to participate in the study and has the mental and physical ability to participate in the study, fill out subjective questionnaires, return for follow-up visits, and comply with prescribed post-operative physical therapy.
3. Patient meets FDA cleared indications for reverse shoulder arthroplasty
4. Patient is between 18-100 years old
5. Patient agrees to also be enrolled in the Arthrex Total Shoulder Registry Study
6. Patient has a standard of care pre-operative CT taken within 6 months that has been submitted for Arthrex Virtual Implant Positioning TM (VIP) planning

Exclusion Criteria:

1. Patient has a history of ipsilateral shoulder arthroplasty
2. A history of shoulder septic arthritis
3. A full thickness subscapularis tear
4. An acute or malunited proximal humeral fracture
5. Chronic locked dislocation
6. Rheumatoid arthritis
7. Tumors
8. Axillary nerve damage
9. Non-functioning deltoid muscle
10. Glenoid vault deficiency precluding baseplate fixation
11. Infection and neuropathic joints
12. Known or suspected non-compliance, drug or alcohol abuse
13. Patients incapable of judgement or under tutelage
14. Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, contraindication for imaging etc.
15. The subject is related to investigator as family members, employees, or other dependent persons
16. Any prior open anterior shoulder surgery that included takedown of the subscapularis tendon or violation of the subscapularis tendon (i.e. Latarjet, Bristow)