Reverse shoulder arthroplasty (RSA) is a type of shoulder replacement surgery that is used primarily to treat shoulder arthritis or severe rotator cuff damage, particularly in cases where the rotator cuff is irreparable. In RSA, the anatomy of the shoulder joint is reversed: the ball and socket of the shoulder joint are swapped. Normally, the humeral head (upper arm bone) is the “ball,” and the glenoid (part of the shoulder blade) is the “socket.” In RSA, a metal ball is attached to the glenoid, and a plastic socket is attached to the humerus.

This reversal allows the deltoid muscle to take over the function of the damaged rotator cuff, which would normally help in lifting the arm. RSA is commonly recommended for people with:
– Rotator cuff tear arthropathy (arthritis resulting from a large, irreparable rotator cuff tear)
– Failed prior shoulder surgeries
– Complex fractures of the shoulder joint
– Severe arthritis with a non-functioning rotator cuff

Recovery from RSA typically involves physical therapy and a gradual return to normal activities over several months.