Occurs in adolescence and is most commonly in overweight boys. Produced by excess weight and the effect of the hormones of puberty on the bones. It can occur after an injury or a fall. More often symptoms are vague with gradually increasing pain and limp. Despite the hip being the problem pain can be felt in the knee or thigh.
Examination shows limitation of movement and tenderness of the hip.
X-rays show characteristic changes. Treatment often involves an operation. There is a great risk of early arthritis of the hip even in those successfully treated. Bow leg is normal from infancy to 2 years. Knock-knee is normal from 2 years to 8 years and then assumes adult alignment.