RecruitingPhase 4Biological interventionPRP for Glenohumeral OsteoarthritisThe glenohumeral joint is the third most common large joint to be affected by OA. Conservative treatments include physical activity, corticosteroid injections, and medications. PRP is an emerging treatment that has shown efficacy in different musculoskeletal conditions. The use of PRP for glenohumeral OA has been described sparingly in the literature but has shown efficacy in a couple studies and case reports. However, all of the previous studies investigating PRP for glenohumeral OA have focused on low-dose PRP preparations (\~3X), and none have compared PRP treatment to saline treatment. This study aims to compare outcomes following single injections of low-dose PRP, high-dose PRP, or saline in patients with glenohumeral osteoarthritis.