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 are growth plate injuries? The growth plate is the area of tissue near the ends of long bones in children and teens that determines what length and shape the bone will be once it is done growing. Each long bone— the thigh bone, the bones in the forearm, and the bones in the hands and fingers—has at least two growth plates, one at each end. Once your child has finished growing, the growth plates close and are replaced by solid bone. The growth plates are weak areas of your child’s growing skeleton, making it easier to injure them. Injuries

What is osteonecrosis? Your bones are made up of living cells that need a blood supply to stay healthy. In osteonecrosis, blood flow to part of a bone is reduced. This causes death of bone tissue, and the bone can eventually break down and the joint will collapse. Osteonecrosis can happen to any bone, but most often it develops in the ends of long bones, such as the: Thigh bone. Upper arm bone. Less often, the bones of the elbows, ankles, feet, wrists, and hands are affected. When the disease involves part of a bone in a joint, it can

What is epidermolysis bullosa? Epidermolysis bullosa is a group of rare diseases that cause fragile skin that leads to blisters and tearing. Tears, sores, and blisters in the skin happen when something rubs or bumps the skin. They can appear anywhere on the body. In severe cases, blisters may also develop inside the body. The symptoms of the disease usually begin at birth or during infancy and range from mild to severe.

What is alopecia areata? Alopecia areata is a disease that attacks your hair follicles (the part of your skin that makes hair). In most cases, hair falls out in small, round patches about the size of a quarter. This causes only a few bare patches. Some people may lose more hair. In only a few people, the disease causes total loss of hair on the head or loss of all body hair. Your hair may grow back, even if you lose all of it. But it may fall out again. No one can tell you when it might fall out

What is Sjögren’s syndrome? Sjögren’s syndrome is a chronic (long-lasting) disorder that happens when the immune system attacks the glands that make moisture in the eyes, mouth, and other parts of the body. The main symptoms are dry eyes and mouth, but the disorder may affect other parts of the body. Many people with Sjogren’s syndrome say they feel tired often (fatigue). They also may have joint and muscle pain. In addition, the disease can damage the lungs, kidneys, and nervous system.

What are sports injuries? Sports injuries are injuries that happen when playing sports or exercising. There are two kinds of sports injuries: Acute injuries occur suddenly when playing or exercising. For example: Sprained ankles. Strained backs. Broken bones. Chronic injuries happen after you play a sport or exercise for a long time.

What are sprains and strains? A sprain is an injury to a ligament (tissue that connects two or more bones at a joint). When a sprain happens, one or more ligaments is stretched or torn. A strain is an injury to a muscle or tendon (fibrous cords of tissue that connect muscle to bone). In a strain, a muscle or tendon is stretched or torn.