The purpose of this study is to perform a prospective randomized trial among female patients undergoing reverse shoulder arthroplasty (RSA) to determine if a larger glenosphere allows greater range of motion without an impact on complications.

A current research debate is whether glenosphere size has a significant clinical impact on a patient's range of motion (ROM) following RSA. Some researchers have shown an association between increased glenosphere size and improved ROM, but no study has determined the absolute minimal motion differences that would be recognizable or beneficial by patients. This is mostly attributable to limitations such as small sample sizes as well as the fact that shoulder dynamics are multifactorial in nature. Most studies have shown an increased ROM with larger glenosphere sizes.1 Because smaller patients are often times female and receive smaller implants, female patients may be more susceptible to limited ROM. The purpose of this study is to determine if a larger glenosphere allows for greater ROM in female patients undergoing RSA.

Inclusion Criteria:

• Female sex
• Diagnosis of rotator cuff tear arthropathy or a massive irreparable rotator cuff tear for which the patient has elected to undergo reverse shoulder arthroplasty
• No history of prior shoulder arthroplasty
• Consent to study participation by signing the informed consent and the Protected Health Information (PHI) form (Attachment B and C)
• Ability to speak, read and write English

Exclusion Criteria:

• Male sex
• Any impairment that would prevent answering the surveys
• No children or adolescents under the age of 18 years old
• No prisoners, pregnant women, or mentally disabled persons
• No Workers' Compensation cases