By: Stephen G. Manifold, MD

Arthritis can affect many joints in the body, including the shoulders. The incidence of shoulder arthritis, while lower than that in hips and knees, appears to be rising. Shoulder arthritis can be categorized based on different causes such as rheumatoid arthritis, post-traumatic arthritis, severe rotator cuff disease and most commonly, degenerative osteoarthritis. The benefits of hip and knee replacement procedures have been widely publicized, however, many people remain unaware that the same replacement techniques are available for the treatment of severe shoulder arthritis. Total shoulder replacement for the treatment of severe arthritis can result in significant reduction in pain and improved arm function (Figure 1).

The anatomy of the shoulder is similar to the hip in that it is a ball and cup joint. The ball, or humeral head, articulates with the cup, or glenoid and each is covered with cartilage. When this cartilage breaks down, pain and stiffness can result. Re-placement procedures in the shoulder can involve just the surface of the humeral head (hemiarthroplasty) or can include both the humeral head and the glenoid (total shoulder replacement). The shoulder joint is stabilized by surrounding ligaments and the rotator cuff muscles. These must be intact and functioning for a total shoulder replacement to be successful.

The primary symptom of shoulder arthritis is pain. This is typically worse with use of the arm, particularly overhead and reaching be-hind. As the arthritis progresses, the patient often develops stiffness of the arm. There may also be difficulty with lying on the affected shoulder and sleeping. Xrays reveal narrowing of the joint space, bone spurs and sometimes bone erosions particularly on the glenoid side (Figure 2). Magnetic resonance imaging (MRI) is useful in evaluating the integrity of the overlying rotator cuff muscles. A total shoulder replacement is not indicated in patients with a large, irrepairable rotator cuff tear due to a high incidence of early failure of the glenoid implant. Replacement of the humeral head alone (hemiarthroplasty) is more appropriate in this group of patients.

Figure 1: Total shoulder replacement

Initial treatment can include pain medicine (acetaminophen, anti-inflammatories, etc.), physical therapy and cortisone injections. Surgical treatment for shoulder arthritis can be considered when nonoperative treatment fails. Shoulder arthroscopy involves placing a camera into the joint through very small incisions and can be used to debride or “clean up” the joint. The cartilage is not replaced with this procedure and as a result, is only useful in patients with milder forms of arthritis. Patients with more severe forms of arthritis require a replacement procedure.

Total shoulder replacement resurfaces the humeral head with a metal ball and stem, and resurfaces the glenoid with a plastic liner (Figure 3). This resurfacing results in removal of the painful tissue and can improve range of motion. The stability of the joint still relies on the surrounding ligaments and muscles. The procedure usually re-quires a 1 or 2 day hospital stay and early

Figure 2: Arthritic shoulder joint.

range of motion is encouraged. Physical therapy is often useful during the postoperative recovery to regain range of motion and strength in the shoulder. Long-term results are generally good with a low incidence of failure due to implant loosening. Shoulder replacements tend to have greater longevity since the shoulder is not a weight-bearing joint like the hip or knee.

Joint replacement procedures aim to relieve pain and improve the quality of life of patients suffering with arthritis. Shoulder arthritis can affect a patient’s ability to raise their arm and perform simple daily activities such as getting dressed and combing hair. When symptoms affect one’s daily

Figure 3: Total shoulder components

activities and other treatments fail, total shoulder replacement is an excellent procedure for alleviating the pain and can substantially improve the patient’s quality of life. Current implant designs strive to recreate the patient’s own anatomy with the goal of improving the longevity of the implants and providing a better functioning shoulder.

Dr Manifold is a board certified Orthopaedic surgeon in Dover, Delaware, specializing in knee and shoulder disorders. He completed his fellowship training in knee replacement and reconstruction at The Insall Scott Kelly Institute/Beth Israel Medical Center, New York, and completed an Orthopaedic residency at New York Orthopaedic Hospital/ Columbia-Presbyterian Medical Center, New York. He graduated medical school from Temple University School of Medicine, Philadelphia. Dr. Manifold’s office practice is at Tooze, Easter & Manifold, MD, PA 720 S. Queen St. Dover, DE. To schedule an appointment, call 302-735-8700.