Arthritis in the shoulder joint itself is relatively similar to arthritis in other locations of the body. However, it occurs far less frequently than hip or knee arthritis. This is because the shoulder is typically not a full weight-bearing joint like the hip or knee and therefore typically is under less stress.
However, as with the hip and knee, shoulder arthritis is characterized by damage to cartilage inside the shoulder joint. Those suffering from this condition experience severe pain, limited function, joint stiffness, and significant diminishment of quality of life. While there is no cure for arthritis, there are many treatments, both non-surgical and surgical, that enable the symptoms to be well treated and for patients to maintain active lifestyles.
Types of Shoulder Arthritis
The most frequently occurring type of arthritis which affects the shoulder are:
Osteoarthritis: This is also known as degenerative joint disease. It is often associated with wear and tear related to a combination of aging, use, genetics, microtrauma, and increased forces across the joint. It can also affect other joints besides the shoulder and is the most common form of arthritis.
Rheumatoid Arthritis: This is an autoimmune disorder, which means your body attacks your healthy cells, which may include the lining of the joint. This leads to inflammation of the joint and joint lining, ultimately wearing away the cartilage surfaces. This inflammatory arthritis can be present in both shoulders at the same time.
Post-Traumatic Arthritis: This can result from a fracture, dislocation, or another shoulder injury. Eventually, this damage can cause the cartilage surface to wear out and disappear.
Cuff Tear Arthropathy: This is the end stage of very large tears of the rotator cuff tendon. The four rotator cuff tendons in your shoulder wrap around the ball portion of the shoulder joint, holding it in place. If one or more of these tendons is heavily torn, this may cause the humeral head to rub against other bones and develop arthritis.
Osteonecrosis: Also known as avascular necrosis, this refers to the disrupted blood supply to an area of the body, which results in that area dying, known as necrosis. Without a blood supply, the bone will slowly collapse, becoming uneven and causing arthritis.
Symptoms of Shoulder Arthritis
As with other joints, the most common shoulder arthritis symptom is pain with activity, when the joint is under stress. Some people have pain even when they are not using the arm, and some have pain only when using it.
Arthritis pain can occur at any time of day and can be present with or without shoulder stiffness. Often the pain is worse with lifting, carrying heavy objects, or after exercising. The pain can often radiate into the arm or, if severe, can radiate down to the elbow and wrist.
Stiffness of the joint is another sign of shoulder arthritis progression. You may experience stiffness as a loss of range of motion in the shoulder. As the motion decreases, you may find that you can do fewer things with your arm, and these activities may be limited due to pain.
Grinding, clicking, or cracking, known as crepitus, may be felt since the cartilage’s surface is irregular with arthritis. It may or may not be painful. Sometimes the shoulder may lock up. Occasionally, because the surfaces are no longer smooth, you may feel the shoulder slide in certain positions.