The term arthritis means inflammation of a joint, and is associated with cartilage damage. Cartilage is a cushioned padding lining the bones that make up a joint in order to absorb stress during movement. Damage of the cartilage in the shoulder joint causes shoulder arthritis. When the cartilage gets damaged, the raw bones begin to painfully rub against each leading to inflammation. The proportion of cartilage damage inflammation varies with the type and stage of arthritis. The most common types of arthritis are:
- Osteoarthritis: Osteoarthritis, also called wear-and-tear arthritis is a degenerative joint disease that affects the cartilage. The cartilage starts to wear away over time, and in extreme cases, nothing remains to protect the bones, causing painful bone-on-bone contact. Osteoarthritis is the most common type of arthritis, which often occurs with advanced age, excessive strain, or other disease, injury or deformity.
- Rheumatoid arthritis: This is an auto-immune disease in which the body’s immune system attacks healthy joints. Occurring most often in women of childbearing age (15 to 44 years), this disease inflames the lining of joints (synovium). Rheumatoid arthritis mostly affects joints of the hands and feet and tends to be symmetrical (affects the same joints on both sides of the body).
Each form of arthritis affects the shoulder differently, with general symptoms including swelling and pain or tenderness for more than two weeks, redness or heat, limitation of motion and early morning stiffness. When severe, arthritis can deform or cause disability in the shoulder joint. In an arthritic shoulder:
- The capsule is swollen.
- The joint space is narrowed and irregular in outline.
- Bone spurs or excessive bone can also build up around the edges of the joint.
Doctors diagnose shoulder arthritis with your medical history, a physical exam and X-rays of the affected part. Computed tomography (CT) scans and magnetic resonance imaging (MRI) scans may also be performed to diagnose arthritis.
There is no cure for arthritis, but the symptoms can be managed. Your doctor may prescribe pain and anti-inflammatory medicine, and advice ice application, rest and occupational therapy or physiotherapy, which includes exercises and heat treatment. To reduce pain, your doctor may administer a steroid injection directly into your joint. In severe cases, surgery may be suggested. Common surgeries for treatment of shoulder arthritis include arthroplasty (replacement of the damaged joint with artificial components) and arthroscopy (using narrow instruments and small incisions to clean out the damaged tissue).