Introduction:Reverse total shoulder arthroplasty (rTSA) has become a popular option for the surgical management of rotator cuff arthropathy and complex fractures of the proximal humerus. However, there is a paucity of studies evaluating outcomes, especially between patients of different age groups. The purpose of this study was to compare functional outcomes and survivorship between patients older than 65 years (o65) and those 65 years and younger (y65).Methods:A retrospective review was conducted at a single academic medical center identifying a consecutive cohort of patients undergoing rTSA between 2018 and 2020. The minimum follow-up time was 2 years. Patients were stratified into two groups for comparative analyses (y65 and o65). Patient demographics, perioperative and postoperative data, and functional outcomes were collected. A Kaplan-Meier survival analysis was conducted to determine survivorship, defined as revision surgery or implant failure.Results:Forty-eight patients were included for final analysis. Nineteen patients comprised the y65 group while 29 patients comprised the o65 group. No difference was observed in Quick Disabilities of the Arm, Shoulder, and Hand scores at baseline nor at the latest follow-up between the two groups. Patients in the y65 group had significantly greater internal and external rotation (IR/ER) from 3 months to 2 years compared with patients in the o65 group (P≤ 0.05). Finally, there were no differences in revision surgery rates between the y65 group and the o65 group (11% vs. 14%,P= 1.0). A KM survival analysis revealed no difference in implant failure, necessitating revision surgery between the two groups at the latest follow-up (P= 0.69).Discussion:Despite a notable difference in the number of baseline comorbidities, there were no notable differences in functional outcomes, survivorship, and revision surgery rates between each cohort. Although both groups had a similar function initially, by 3 months postoperatively, the y65 group had markedly greater range of motion in IR and ER. Longer term survivorship is needed; however, rTSA may offer a reliable option for shoulder reconstruction even in the y65 patient group.