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 is cicatricial alopecia? Cicatricial alopecia is a group of conditions that destroy hair follicles. Hair follicles are the part of the skin where the hair grows. The follicles are replaced with scar tissue. This means the hair will fall out and not grow back.

What is bursitis? Bursitis is a common condition that causes swelling and pain around muscles and bones. Bursitis is the swelling of the bursa, a small, fluid-filled sac that acts as a cushion between a bone and other moving parts, such as muscles, tendons, or skin.

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 are shoulder problems? Most shoulder problems happen when soft tissues in the joint and shoulder region break down.

What is tendinitis? Tendinitis is swelling and pain in a tendon, which is tissue that connects muscles to bones. It is a common condition, usually caused by repeated injuries to a tendon.

What are arthritis and rheumatic diseases? The term arthritis is often used to refer to any disorder that affects the joints. There are more than 100 rheumatic diseases. Rheumatic diseases usually affect joints, tendons, ligaments, bones, and muscles. Some rheumatic diseases can also affect the organs.

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.