Shoulder Replacement Surgery
Shoulder replacement surgery (total shoulder arthroplasty) is a surgical solution for shoulder pain that involves replacing arthritic joint surfaces and damaged bone with artificial devices.
The shoulder is comprised of the collarbone (clavicle), the shoulder blade (scapula), and the upper arm bone (humerus). These three bones come together to form the shoulder joint. The range of motion afforded the shoulder comes from the ball and socket joint that is formed by the upper arm bone (humeral head) that fits into the socket of the scapula bone, called the glenoid.
Cartilage allows bones to move smoothly on each other without pain. When this ball-and-socket joint degenerates, often due to arthritis or shoulder fracture, these smooth surfaces become rough and bones rub against each other causing pain.
Severe shoulder arthritis is quite painful, and can cause restriction of motion. Osteoarthritis is not the only type of arthritis that affects the shoulder joint. Systemic diseases, such as rheumatoid arthritis, may affect any joint in the body. Whatever the type or cause of the arthritis, the shoulder may become painful and difficult to use.
While this may be tolerated with some medications and lifestyle adjustments, there may come a time when surgical treatment is necessary. Although there are different types of shoulder replacements, the concept remains that the damaged surfaces of the bone are replaced.
Who is a Candidate for Shoulder Replacement Surgery?
Typically, patients who present the following conditions may be good candidates for shoulder replacement:
- Long-term shoulder pain not alleviated with more conservative treatments
- Pain and stiffness persists with everyday activities
- Shoulder pain and stiffness interferes with sleep
- Suffers severe degenerative arthritis (osteoarthritis)
- Severe fracture or severely damaged tissues involving the shoulder joint
- Suffers avascular necrosis (loss of blood supply to the upper end of the humerus)
- Former shoulder surgery failure
- Tumor in or around the shoulder
- Suffers severe loss of motion or who are experiencing weakness in the shoulder
- Suffers from rheumatoid arthritis where inflammation has destroyed the shoulder cartilage
What Happens During Shoulder Replacement Surgery?
Total shoulder replacement surgery involves the replacement of the damaged bone and cartilage with metal and plastic implants (prostheses), thus alleviating pain and restoring mobility.
The surgery is most often done under general anesthesia so that the patient does not feel the procedure. The surgeon will make an incision in the front of the shoulder to expose the damaged joint. Next, the damaged arthritic head (ball) of the humerus bone is removed and the remaining bone is prepared to accept the artificial implant. This portion of the prosthesis is made of very strong alloy metal and has a stem that fits inside the remaining arm bone. The stem may be cemented into place to provide additional stability if the upper arm bone is soft. The socket of the shoulder is prepared and a plastic liner is cemented in place. Not all patients require this artificial glenoid piece, however, most patients with osteoarthritis and rheumatoid arthritis do benefit from it. The rotator cuff muscles are repaired and the wound is closed.
Shoulder replacement surgery takes about two hours. As with any surgery, there are risks involved, although complications are not frequent. Complications may include:
- Prosthetic loosening
- Glenohumeral instability
- Rotator cuff tears
- Blood Clots
- Neural injury
- Deltoid muscle dysfunction
Advances in surgical techniques and prosthetic innovations have helped to reduce the occurrence of these complications.
Most patients leave the hospital in one to three days. Pain medication is usually required for the first few weeks after surgery. The postoperative pain should decrease each week and most patients are able to stop narcotic pain medication by three weeks. Over-the-counter medications may be recommended for occasional aches and pains.
Total rehabilitation from shoulder replacement surgery usually takes three to six months. Generally, within that time frame, patients are able to return to most normal activities and emphasis is placed on strengthening the muscles around the shoulder and maintaining range of motion.