Sixty-two patients aged 80 years or older with a 3- or 4-part displaced proximal humerus fracture were randomized to receive a reverse shoulder arthroplasty or conservative treatment with a sling. The primary outcome of interest was the Constant score at 12 months post-operation. Secondary outcomes of interest included the Disability of the Arm, Shoulder and Hand (DASH) score, the Short-Form 12 (SF-12) mental and physical component scores and pain on a Visual Analog Scale (VAS). Follow up was performed up to 12 months post-treatment. Results revealed no significant differences in all outcomes at all time-points, with the exception of VAS pain scores at 12 months which were significantly lower in the surgical group compared to the conservative group.