The purpose of this study is to evaluate the use and efficacy of the Reverse® Shoulder Prosthesis for treatment of rotator cuff deficiency in subjects who are candidates for a total shoulder replacement (primary and revision subjects).

Reverse shoulder arthroplasty for the treatment of rotator cuff deficiency and glenohumeral arthritis have shown favorable outcomes in pain and function over the short and medium term. A prospective, multi-center study on the outcomes of subjects treated with the RSP would be a valuable addition to the literature and give important information regarding an ever-increasing treatment option for subjects with rotator cuff deficiency. The study will take place at multiple sites across the United States and will be managed by the DJO Surgical Clinical Affairs Department. The study will include only subjects who meet the indications for use criteria for the Reverse® Shoulder Prosthesis and who are candidates for total shoulder replacement surgery.

Inclusion Criteria:

• Subject must be a candidate for a total shoulder joint replacement
• Subject must be diagnosed with one or more of the following conditions:

Irreparable rotator cuff tear with gleno-humeral arthritis; Failed rotator cuff surgery with gleno-humeral instability or antero- superior escape; Failed shoulder replacement surgery

• Subject has a functional deltoid muscle
• Subject's joint must be anatomically and functionally suited to receive the selected implant
• Subject is 60 years of age or older (≥ 60 yrs of age) at time of consent
• Subject is likely to be available for all study visits
• Subject is able and willing to sign the informed consent and follow study procedures
• Subject is not pregnant

Exclusion Criteria:

• Subject has a non-functional deltoid muscle
• Subject has a mental condition(s) that may interfere with the subject's ability to give an informed consent or willingness to fulfill the study requirements (i.e., severe mental retardation such that the Subject cannot understand the informed consent process, global dementia, prior strokes that interfere with the Subject's cognitive abilities, senile dementia, and Alzheimer's Disease)
• Subject is a prisoner
• Subject has high levels of physical activity (ex. competitive sports, heavy physical labor)
• Subject is pregnant
• Subject has an active infection or sepsis
• Subject has loss of ligamentous structures
• Subject has a history of alcoholism or other addictions (current or past)
• Subject has muscular, neurological or vascular deficiencies which compromise the affected extremity (i.e., Parkinson's Disease, Syringomyelia and Multiple Sclerosis, Charcot joints)
• Subject has severe glenoid bone loss
• Subject has known materials sensitivity (to metals)
• Subject is younger than 60 years of age (< 60 years of age) at consent

Subjects who are 60 years of age or older at the time of consent and are suffering from a grossly rotator cuff deficient shoulder joints with severe arthropathy or have a previously failed joint replacement with a grossly rotator cuff deficient shoulder joint.