There’s no evidence of a genetic link with Perthes disease. Your children have the same chances of getting it as anyone. And scientists still don’t know what causes it. Poor nutrition is one possible theory. Abnormal blood clotting increases the chances of Perthes.
In this condition, the blood supply to the growth plate at the top of the femur (thighbone) is blocked. Forming blood that clots easier and faster than normal may lead to blockage of the small arteries going to the femoral head.
Be sure and let your pediatrician know of your own medical history of Perthes. Watch for any unusual signs and symptoms such as hip pain or limp when walking. When the doctor examines the hip, the motion of the hip is abnormal and restricted. Turning the leg inward causes pain. This usually means that the hip is inflamed and may have inflammatory fluid (called an effusion) present in the hip joint.
Sometimes problems in the hip cause knee pain instead of the hip pain. A child with knee pain and no obvious reason for it, or an abnormal walking pattern, should be examined for possible Perthes disease. X-rays of the hips are usually taken to make sure that Perthes disease is not missed.