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 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? 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 acne? Acne is a common skin condition that happens when hair follicles under the skin become clogged. Oil and dead skin cells plug the pores, and outbreaks of lesions (often called pimples or zits) can happen. Most often, the outbreaks occur on the face but can also appear on the back, chest, and shoulders. For most people, acne tends to go away by the time they reach their thirties, but some people in their forties and fifties continue to have this skin problem.

What are heritable disorders of connective tissue? There are more than 200 heritable disorders of connective tissue that can affect the tissues between the cells of your body that give tissues form and strength. All of these diseases are directly related to problems in genes that are responsible for building connective tissues. The disorders are called “heritable,” because they are passed on from parent to child. Some heritable disorders of connective tissue change the look and growth of skin, bones, joints, heart, blood vessels, lungs, eyes, and ears. Others change how these tissues work. Many, but not all, are rare

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 are knee problems? Knee problems happen when you injure or develop disease in your knee and it can’t do its job. The knees provide stable support for the body. They also allow your legs to bend and straighten. Both flexibility and stability are needed to stand, walk, run, crouch, jump, and turn. Other parts of your body help the knees do their job. These are: Bones. Cartilage. Muscles. Ligaments. Tendons.

What are sports injuries in youth? Although sports injuries can range from scrapes and bruises to serious brain and spinal cord injuries, most fall somewhere between the two extremes. Here are some of the more common types of injuries: Muscle sprains and strains. Injuries of a growth plate, area of tissue at the end of the long bones in growing children and teens. Injuries from overuse of muscles and tendons. Learn more about sports injuries.

¿Qué es la osteogénesis imperfecta? La osteogénesis imperfecta es una enfermedad que hace que los huesos se rompan (se fracturen) fácilmente. También se le conoce como la enfermedad de los huesos de cristal. Sus síntomas pueden ser leves o graves, dependiendo del tipo de osteogénesis imperfecta que tenga.