Total shoulder arthroplasty or replacement is one of the most successful joint replacement surgeries done. The main indication for performing a shoulder replacement surgery is arthritis of the shoulder joint due to various degenerative processes. The degeneration causes the joint surface. The worn out surfaces come into contact with each other and this causes pain and restriction of movements of the shoulder. The surgery is mainly intended to relieve pain and restore mobility of the shoulder.
Conventional shoulder replacement involves removal of the rounded head of the humerus bone and replacing it with a prosthetic head which fixes into the humerus bone. The socket or the gleniod of the scapula is replaced by an artificial socket.
Most commonly the head is made of a metal and the socket is made of polyethylene.
Complicated and badly damaged fractures of the head of the humerus may be treated by hemiarthroplasty , where only the ball is replaced.
Most patients will be able to resume normal activities after surgery with the ability to perform overhead shoulder activities.
A recent advance in shoulder replacement is a “reverse shoulder replacement”. The shoulder joint is unique in design as the ball of the shoulder simply rests against the socket rather than being embedded in it. This is the reason for its increased range of movements. But this compromises its stability which is maintained by surrounding muscles and ligaments. In diseases of the shoulder where the joint degenerates along with damage of the surrounding ligaments and muscles, the regular shoulder replacement cannot be successful as even the prosthetic joint relies on the ligaments and muscles for its stability. This is the main reason for performing a reverse shoulder replacement where the ball is placed in the natural socket and the socket is placed in the humerus so that the socket now rests against the ball offering more stability.
The usual hospital stay after a shoulder replacement surgery is about 3-5 days. Shoulder strengthening exercises and rehabilitation exercises are started from post op day 1, and usually by 4-6 weeks patients will be able to go back to work. Sports activities can be resumed in about 4-6 months.