ABSTRACT
Perthes’ disease is an osteochondritis of the hip which occurs as a result of ischaemic necrosis of the upper femoral epiphysis. It occurs most commonly between 4 and 8 years of age (range 2-16 years), is commoner in boys than girls (4:1), and is bilateral in 10% of cases. Occasionally, there is a family history but there is no evidence that it is an inherited disorder. There is a slightly increased risk with breech delivery and in lower socio-economic groups: it is commoner in urban populations. Children with Perthes’ disease have a lower mean birth weight and a delayed bone age (average 21 months).
