By Benjamin F. Donohue, MD MBA FAAOS
Shoulder replacement surgery is a safe and effective procedure to relieve pain and improve shoulder function. It allows patients to resume everyday activities and improve their quality of life.
Over 100,000 shoulder replacements are performed each year in the United States, compared to approximately 400,000 hip replacements and 700,000 knee replacements. The number of shoulder replacements is increasing at a faster rate each year than that of the other two procedures due to improved technology and more situations where the surgery is appropriate.
What shoulder joint disorders can be treated with shoulder replacement surgery?
- Osteoarthritis. This condition causes the articular cartilage lining of the “ball” (head of the humerus bone) and “socket” (glenoid) to thin and bone spurs to develop. The most common cause is a genetic predisposition. However, a history of shoulder dislocations or other injuries can also result in osteoarthritis, which causes stiffness and pain in the joint.
- Longstanding rotator cuff tears with osteoarthritis. When rotator tears are large and present for years, the head of the humerus elevates enough that the ball and socket can become poorly aligned. This predisposes the shoulder to the same changes seen with osteoarthritis (e.g. thinning of articular cartilage, bone spurs), although in a different pattern than seen without the rotator cuff tear.
- Massive, irreparable rotator cuff tears. Sometimes rotator cuff tears are so severe and the muscle so atrophied that a rotator cuff repair cannot be performed successfully. Then, a shoulder replacement is a better surgical treatment.
- Severe fractures of the shoulder. Some fractures of the humerus or the glenoid bones in certain patients are better treated with a shoulder replacement than with a plate and screws.
- Avascular necrosis of the humerus. Medications, systemic disease, or trauma can disrupt the blood supply to the head of the humerus which leads to early osteoarthritis of the shoulder.
- Chronic dislocations of the shoulder joint and tumors of the shoulder joint can also be treated with shoulder replacement surgery.
When should shoulder replacement surgery be considered?
Most patients who have shoulder replacement surgery are 50 or older. People who benefit most from surgery have:
- Shoulder pain that interferes with everyday activities, such as reaching up to a cabinet, dressing, or washing.
- Nighttime shoulder pain that interferes with sleeping.
- Loss of motion and/or weakness in the shoulder.
Candidates for surgery have failed to improve with non-operative treatments such as anti-inflammatory medications, physical therapy, and cortisone injections.
What are the types of shoulder replacement surgery?
- “Anatomic” shoulder replacement. In the original design of the shoulder replacement, a plastic socket is cemented onto the patient’s glenoid, and a metal ball is placed at the top of the humerus. This is an appropriate procedure to treat shoulder osteoarthritis, avascular necrosis, and some fractures.
- “Reverse” shoulder replacement. This is a more recent design that the FDA approved in 2003. A metal ball is locked into place on the glenoid side of the joint, while a socket is placed on the top of the humerus bone. This exchange of positions allows the shoulder to better engage the deltoid muscle to power more shoulder movement. The procedure is appropriate for longstanding rotator cuff tears with osteoarthritis, irreparable rotator cuff tears, and certain fractures. More reverse replacements are now performed each year in the U.S. than anatomic shoulder replacements.
- Hemi- shoulder replacement. This operation involves only replacing the head of the humerus with a metal component and not altering the glenoid socket. The procedure is appropriate for some fractures.
Are there any recent technological advances in shoulder surgery?
We use preoperative CT scans and specialized computer software to determine the optimal position of surgical components and the optimal size of these components. The software uses 3D printing to create a guide that is placed into the shoulder during surgery to find the exact axis of the glenoid. These advances improve the accuracy of component positioning.
What happens after shoulder replacement surgery?
Most patients spend one night in the hospital after surgery. Post-surgery pain is controlled with medications, and a sling is worn for six weeks. Physical therapy is recommended for the first several months, and patients are given weight-lifting limits for the affected arm.
Dr. Donohue is a Fellow of the American Academy of Orthopedic Surgeons and Board Certified in Orthopedic Surgery and Orthopedic Surgery Sports Medicine subspecialty by the American Board of Orthopaedic Surgery. He joined Cayuga Orthopedics in 2016 and assists in the care of local athletes at both Cornell University and Ithaca College. In addition to his medical degree from Columbia University College of Physicians and Surgeons, Dr. Donohue received a Master of Business Administration from the Harvard Business School in Cambridge, MA.