The shoulder is a ball-and-socket joint, with the ball on the end of the upper arm bone (humerus) fitting into the socket of the shoulder bone (scapula). In total shoulder replacement surgery, the surgeon typically replaces the damaged ball at the end of the upper arm bone as well as the shoulder bone socket, capping them with artificial surfaces lined with metal and/or plastic, and sometimes held in place with surgical cement. For some patients, only one of the two shoulder elements needs repaired/replaced; this would be called a partial shoulder replacement.
The procedure itself takes a little more than one hour, and most patients go home one day after surgery, unless more extensive rehab is necessary. Recent studies have shown that almost all patients who have had total shoulder replacement surgery have fully functioning shoulders ten years after their procedure. After returning home, patients will have their arm in a soft sling for up to six weeks, and typically begin physical therapy in two weeks.