Another type of shoulder replacement is called reverse total shoulder replacement. In a reverse total shoulder replacement, the socket and ball shoulder implants are switched or “reversed." The ball is fixed to the socket, and the socket is fixed to the upper end of the humerus, which will rely on different muscles to function than an anatomic total shoulder. Reverse shoulder replacements are used for people with completely torn rotator cuffs and severe arm weakness, those with effects of severe arthritis from chronic rotator cuff tears called cuff tear arthropathy, cases of failed previous shoulder replacements, and complex humeral head fractures with or without underlying arthritis.