The treatment of rotator cuff arthropathy is still a matter of debate. Up to now a hemiarthroplasty was usually used. We report the results obtained with a reversed shoulder prosthesis (Delta prosthesis, De Puy) in seven patients with severe rotator cuff arthropathy. The mean Constant score increased from 17.9/100 preoperatively to 56.7/100 postoperatively. The mean follow-up was 16 months. Loosening was not observed on follow-up x-rays.