50 consecutive patients, who were undergoing reverse shoulder arthroplasty due to the diagnosis of cuff tear arthroplasty, were randomly assigned to either receive a concentric or an eccentic glenosphere. This study aimed to investigate whether the inferior positioning of the center of rotation with eccentric glenosphere designs decreases the adduction deficit before impingement occurs and improves clinical outcome. No difference was found in the notching rates and clinical outcomes between either group following the reverse shoulder arthroplasty procedure. Inferior glenosphere overhang greater than 3.5mm was shown to prevent scapular notching.