What is psoriasis? Psoriasis is a chronic (long-lasting) disease in which the immune system works too much, causing patches of skin to become scaly and inflamed. Most often, psoriasis affects the: Scalp. Elbows. Knees. The symptoms of psoriasis can sometimes go through cycles, flaring for a few weeks or months followed by times when they subside (or go into remission). If you have psoriasis, you may have a higher risk of getting other serious conditions, including: Psoriatic arthritis. Heart attack or stroke. Mental health problems, such as low self-esteem, anxiety, and depression.

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 is osteoarthritis? Osteoarthritis is a joint disease that happens when the tissues in the joint break down over time. It is the most common type of arthritis and is more common in older people. People with osteoarthritis usually have joint pain and, after rest, stiffness (inability to move easily) for a short period of time. The most commonly affected joints include the: Hands (ends of the fingers and at the base and ends of the thumbs). Knees. Hips. Neck. Lower back. Osteoarthritis affects each person differently. For some people, osteoarthritis does not affect day-to-day activities. For others, it causes

What is osteogenesis imperfecta? Osteogenesis imperfecta (OI) is a disease that causes your bones to break (fracture) easily. OI is also called brittle bone disease. Your symptoms may be mild or severe, depending on the type of OI you have.

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 alopecia areata? Alopecia areata is a disease that causes hair loss. In alopecia areata, the immune system attacks the structures in skin that form hair (hair follicles). Alopecia areata usually affects the head and face, though hair can be lost from any part of the body. Hair typically falls out in small, round patches about the size of a quarter. In some cases, hair loss is more extensive.

What is ichthyosis? Ichthyosis is a group of skin disorders. It leads to dry, itchy skin that appears scaly, rough, and red. The symptoms can range from mild to severe. Ichthyosis can affect only the skin, but sometimes the disease can affect internal organs, too.

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