PHYSEAL SLOPE IN PERTHES-DISEASE

In 40 children with unilateral Perthes' disease, we measured the physe al slope, the angle between the physeal plane and the axis of the femo ral shaft, from radiographs taken early in the disease, Thirty-seven o f the 40 hips were classified as Catterall grades III and IV, Head-at- risk signs were present in 23. We found no statistically significant d ifference in the physeal slope between the involved and normal hips (p =0.20), those with or without head-at-risk signs (p=0.96), those with or without lateral epiphyseal subluxation (p=0.82), and different Catt erall (p=0.56) or lateral pillar (p=0.67) gradings.