Shoulder arthritis is a condition in which the normally smooth cartilage covering the ball and socket of the shoulder joint is lost due to disease, wear and tear, injury or surgical mistake. As a consequence, there is bone on bone rubbing between these two joint surfaces, leading to shoulder pain, stiffness, difficulty sleeping, and the inability to do activities of daily living, work and sports. Shoulder arthritis is a particularly painful condition that affects the shoulder joints. Three major types of arthritis generally affect the shoulder:
- Rheumatoid arthritis
- Posttraumatic arthritis
The classic form of arthritis associated with wear and tear is osteoarthritis. It is a degenerative condition that destroys the smooth outer covering (articular cartilage) of bone. This can affect the shoulders as well as other joints like your knees, hands and hips. It usually affects people over 50 years of age, and is more common in the acromioclavicular joint than in the glenohumeral shoulder joint.
Another common form of shoulder arthritis is an autoimmune condition called rheumatoid arthritis. It is a systemic inflammatory condition of the joint lining, or synovium. It can affect people of any age and usually affects multiple joints on both sides of the body. Rheumatoid arthritis affects the joint lining and can cause joint swelling as well. It can cause erosion of the shoulder bones and deformity of the shoulder joints over time.
Posttraumatic arthritis is a form of osteoarthritis that develops after an injury, such as a fracture or dislocation of the shoulder. Arthritis can also develop after a rotator cuff tear.
Symptoms of Shoulder Arthritis
As with other joints, the most common symptom of shoulder arthritis is pain with activity. If the glenohumeral shoulder joint is affected, the pain is centered in the back of the shoulder and may intensify with changes in the weather. The pain of arthritis in the acromioclavicular joint is focused on the front of the shoulder. Someone with rheumatoid arthritis may have pain in all these areas if both shoulder joints are affected.
In time, pain can occur at rest, and may even interrupt sleep. As the cartilage disappears, the joint becomes stiff, reducing range of motion and limiting activity, often causing interference with even the most common tasks of everyday life, such as dressing, reaching for objects and even personal hygiene. As joint motion is lost, tasks such as driving, athletic activity, housework, and even writing and computer work can be affected. The pain is frequently centered on the back of the shoulder, but commonly is felt all the way down the arm to the elbow.
Perhaps the most disabling symptom for most people is the loss of sleep, as it frequently becomes difficult to find a comfortable position either on the affected or unaffected side.
Motion is often severely affected, and may be accompanied by cracking, grinding or catching (crepitus) as the ball/socket bones rub against one another.