As the old saying goes, "If it's not broke, don't fix it." Joint replacements don't last forever. Just removing the damaged part and replacing it can cause problems. The muscles around the joint must be cut and a certain amount of bone removed.

Many doctors would agree when only half the joint is a problem then a hemiarthroplasty is the way to go. This operation only replaces the part of the joint that is damaged. This is usually the head of the humerus or ball portion that fits into the socket. Any part of the joint that is still in good health should be saved.