Fibrous dysplasia is a chronic disorder in which an abnormal development of fibrous tissue causes bones to expand. Any bone can be affected. More than one bone can be affected at any one time, and, when multiple bones are affected, it is not unusual for them to all be on one side of the body. However, fibrous dysplasia does not spread from one bone to another.
Osteogenesis Imperfecta in Children
Osteogenesis imperfecta (OI) is an inherited disorder of the tissue that holds the body together (connective tissue). It is present at birth (congenital). A child born with OI may have signs and symptoms that range from mild to severe. He or she may have soft bones that break(fracture) easily, bones that are not formed normally, and other problems.
Osteomyelitis is an inflammation or swelling of bone tissue. It’s most often caused by an infection. Bone infection may occur for many reasons and can affect children or adults.
Paget Disease of the Bone
Paget disease of the bone is a chronic bone disorder. It causes bones to become enlarged and deformed. Bone may become dense, but fragile, because of excessive breakdown and deformation of bone. The disease is the most common bone disorder after osteoporosis in people over age 50.
Primary hyperparathyroidism is a metabolic disorder in which one or more of the parathyroid glands produces too much parathyroid hormone. This can result in a loss of bone tissue. A job of the parathyroid hormone is to keep blood calcium levels from going too low. This is done by releasing calcium from bones. The hormone also conserves calcium that would be excreted by the kidneys, and increases how much calcium is absorbed from food. When the hormone overacts, the result is a rise in the blood calcium level. Too much parathyroid hormone causes too much calcium to be released from bone.
Avascular necrosis develops when blood supply to a bone is cut off. This causes the bone to die and can cause pain and joint problems.