Shoulder replacement surgery is an option for treatment of severe arthritis of the shoulder joint. Arthritis is a condition that affects the cartilage of the joints. As the cartilage lining wears away, the protective lining between the bones is lost--when this happens, painful bone-on-bone arthritis develops. Severe shoulder arthritis is quite painful, and can cause restriction of motion. While this may be tolerated with some medications and lifestyle adjustments, there may come a time when surgical treatment is necessary.

Total shoulder replacement surgery alleviates pain by replacing the damaged bone and cartilage with a metal and plastic implant. The shoulder joint is a ball-and-socket joint, much like the hip joint. The ball is the top of the arm bone (the humerus), and the socket is within the shoulder blade (scapula). This joint allows people an enormous range of motion at the shoulder.

When shoulder replacement surgery is performed, the ball is removed from the top of the humerus and replaced with a metal implant. This is shaped like a half-moon and attached to a stem inserted down the centre of the arm bone. The socket portion of the joint is shaved clean and replaced with a plastic socket that is cemented into the scapula.

Shoulder replacement surgery lasts about two hours. The incision for the surgery is along the front of the shoulder joint and usually about four to six inches long. The surgery is most commonly done under general anaesthesia.

Patients who have tried the usual treatments for shoulder arthritis, but have not been able to find adequate relief, may be a candidate for shoulder replacement surgery. Patients considering the procedure should understand the potential risks of surgery, and understand that the goal of joint replacement is to alleviate pain. Patients generally find improved motion after surgery, but these improvements are not as consistent as the pain relief following shoulder replacement surgery.

Hospital stays vary from one to three days for most patients.

You will be sent home wearing a sling and you should not attempt to use the arm except as specifically instructed by your doctor.

Most physicians will begin some motion immediately following surgery, but this may not be true in every case. Usually within two to three months, patients are able to return to most normal activities and place an emphasis on strengthening the muscles around the shoulder and maintaining range of motion.

As always, risks of surgery include risks of general anaesthesia which tend to be dependent on other medical issues you may have. Some specific risks of shoulder replacement surgery include:

• Infection
  Infection around an implanted joint is a very serious complication and therefore there are significant measures taken to avoid this complication. If an infection develops, the entire implanted joint may need to be removed in order to eradicate the infection.
• Dislocation/Instability
  Because of the ball-and-socket design of the implanted joint, it is important that the surgeon balance the soft-tissues around the shoulder to ensure it is not pulled out of position.
• Loosening of the Implant
  Over time, implanted joints may loosen. Developments are constantly being made to produce longer-lasting implanted joints, but this has not been perfected. If an implant loosens to the point where patients are having significant problems, a revision surgery may need to be performed (a replacement of a joint replacement).
• Damage to Nerves or Blood Vessels
  The shoulder is a tight space, and many important structures pass just next to the shoulder joint. The nerves that send and receive messages to and from your hand and arm, as well as the blood vessels that provide circulation, sit very close to the shoulder joint. One complication of this surgery is damage to a blood vessel or nerve.