What is psoriatic arthritis? Psoriatic arthritis can occur in people who have psoriasis (scaly red and white skin patches). It affects the joints and areas where tissues attach to bone. The joints most often affected are: The outer joints of the fingers or toes. Wrists. Knees. Ankles. Lower back.

What are autoimmune diseases? Autoimmune diseases refer to problems with the immune system, which usually fights off viruses, bacteria, and infection. The problem causes your immune cells to attack your body by mistake. These diseases can affect almost any part of the body.

What is joint replacement surgery? Joint replacement surgery removes damaged or diseased parts of a joint and replaces them with new, man-made parts. Replacing a joint can reduce pain and help you move and feel better. Hips and knees are replaced most often. Other joints that can be replaced include the shoulders, fingers, ankles, and elbows.

What is osteonecrosis? Osteonecrosis is a bone disease. It results from the loss of blood supply to the bone. Without blood, the bone tissue dies. This causes the bone to collapse. It may also cause the joints that surround the bone to collapse. If you have osteonecrosis, you may have pain or be limited in your physical activity. Osteonecrosis can develop in any bone, most often in the: Thigh bone (femur). Upper arm bone (humerus). Knees. Shoulders. Ankles. It is also called: Avascular necrosis. Aseptic necrosis. Ischemic necrosis.

What is vitiligo? Vitiligo is a chronic (long-lasting) disorder that causes areas of skin to lose color. When skin cells that make color are attacked and destroyed, the skin turns a milky-white color. No one knows what causes vitiligo, but it may be an autoimmune disease. In people with autoimmune diseases, the immune cells attack the body’s own healthy tissues by mistake, instead of viruses or bacteria. A person with vitiligo sometimes may have family members who also have the disease. There is no cure for vitiligo, but treatment may help skin tone appear more even.

What is back pain? Back pain is one of the most common medical problems in the United States. It might feel like a dull, constant ache or a sudden, sharp pain. Back pain can result from: An accident. A fall. Lifting something heavy. Changes that happen in the spine as you age. A disorder or medical condition. Treatment depends on the cause and symptoms of your pain. You can do things to improve your health and lower your chance of developing chronic (long-lasting) back pain.

What is Sjögren’s syndrome? Sjögren’s syndrome is a disease that affects the glands that make moisture. It most often causes dryness in the mouth and eyes. It can also lead to dryness in other places that need moisture, such as the nose, throat, and skin. Sjögren’s syndrome is also a rheumatic disease, which affect: Joints. Tendons. Ligaments. Bones. Muscles. The signs and symptoms of rheumatic diseases can include: Redness or heat. Swelling. Pain. Loss of function. Primary Versus Secondary Sjögren’s Syndrome Doctors have two categories for Sjögren’s syndrome: Primary form: Occurs if you do not have other rheumatic diseases. Secondary