What is Arthritis of the Shoulder?
The term arthritis literally means inflammation of a joint but is generally used to describe any condition in which there is damage to the cartilage. Damage of the cartilage in the shoulder joint causes shoulder arthritis. Inflammation is the body's natural response to injury. The warning signs that inflammation presents are redness, swelling, heat, and pain.
The cartilage is padding that absorbs stress. The proportion of cartilage damage and synovial inflammation varies with the type and stage of arthritis. Usually, the initial pain is due to inflammation. In the later stages, when the cartilage is worn away, most of the pain comes from the mechanical friction of raw bones rubbing on each other.
What are the Types of Shoulder Arthritis?
There are over 100 different types of arthritis. The most common are osteoarthritis and rheumatoid arthritis.
Osteoarthritis
Osteoarthritis is also called a degenerative joint disease; this is the most common type of arthritis, which occurs often in the elderly. This disease affects the cartilage, the tissue that cushions and protects the ends of bones in a joint.
With osteoarthritis, the cartilage starts to wear away over time. In extreme cases, the cartilage can completely wear away, leaving nothing to protect the bones in a joint, causing bone-on-bone contact. Bones may also bulge or stick out at the end of a joint and are called bone spurs.
Osteoarthritis causes joint pain and can limit your normal range of motion (the ability to freely move and bend a joint). When severe, the shoulder joint may lose all movement, making your disabled.
Rheumatoid Arthritis
This is an autoimmune disease in which the body's immune system (the body's way of fighting infection) attacks healthy joints, tissues, and organs. Occurring most often in women of child-bearing age (15-44 years), this disease inflames the lining (or synovium) of joints. It can cause pain, stiffness, swelling, and loss of function in the joints. When severe, rheumatoid arthritis can deform or change a joint.
Rheumatoid arthritis mostly affects the joints of the hands and feet and tends to be symmetrical. This means the disease affects the same joints on both sides of the body (both hands or both feet) at the same time and with the same symptoms. No other form of arthritis is symmetrical. About two to three times as many women as men have this disease.
Causes of Shoulder Arthritis
Osteoarthritis is caused by the wearing out of the cartilage covering the bone ends in a joint. This may be due to excessive strain over prolonged periods of time, or due to other joint diseases, injury or deformity. Primary osteoarthritis is commonly associated with ageing and general degeneration of the joints.
Secondary osteoarthritis is generally the consequence of another disease or condition, such as repeated trauma or surgery to the affected joint, or abnormal joint structures from birth. Rheumatoid arthritis is often caused when the genes responsible for the disease is triggered by infection or any environmental factors. With this trigger, the body produces antibodies, the defence mechanism of the body, against the joint and may cause rheumatoid arthritis.
Symptoms of Shoulder Arthritis
There are several forms of arthritis and the symptoms vary according to the form of arthritis. Each form affects the body differently. Arthritic symptoms generally include swelling and pain or tenderness in the joints for more than two weeks, redness or heat in a joint, limitation of motion of a joint and early morning stiffness.
In an arthritic shoulder:
- The cartilage lining is thinner than normal or completely absent. The degree of cartilage damage and inflammation varies with the type and stage of arthritis.
- The capsule of the arthritic shoulder is swollen.
- The joint space is narrowed and irregular in outline; this can be seen in an X-ray image.
- Bone spurs or excessive bone can also build up around the edges of the joint.
Diagnosis of Shoulder Arthritis
Your doctor will diagnose arthritis with a medical history, a physical exam and X-rays of the affected part. Computed tomography (CT) scans and magnetic resonance imaging (MRI) scans are also ordered to diagnose arthritis.
Treatment Options for Shoulder Arthritis
Your doctor may prescribe anti-inflammatory medicine and may recommend occupational therapy or physiotherapy, which includes exercises and heat treatment. In severe cases, surgery may be suggested. The type of surgery depends on the age and severity of the condition. In the elderly with severe arthritis, joint replacement is a good option. A common surgery for the treatment of shoulder arthritis is arthroplasty (replacement of the damaged joint), which may be total shoulder arthroplasty or hemiarthroplasty.