This is a genetic disorder in which fibrous tissue develops in place of bone. This makes the bone weak which causes it to bend. Usually only one bone is affected. If many bones are involved along with skin patches and hormonal problems then it is called McCune Albright syndrome. The child will complain of pain, deformity of limb. Radiographs will show a ground glass appearance, expansion of bone and bowing. In mild cases only observation is required. In severe cases curettage with intramedullary nail may be required. This condition may persist for many years however in the presence of intramedullary nail the incidence of fracture is less