To know the proportional contribution of causative factors to the femoral shortening in Legg-Calve-Perthes disease

In twenty piglets, 4 to 5 weeks old, vascular supply to the capital femoral epiphysis was interrupted by ligating the femoral neck containing the epiphyseal artery.

Mean femoral shortening in piglets sacrificed at 4 weeks after devascularization was 7.4 mm. In detail, the shortening was 2.5 mm (34%) in the epiphysis and 4.9 mm (66%) in the neck and diaphysis. Mean femoral shortening in piglets sacrificed at 8 weeks after operation was 12.1 mm. The distribution of shortening was 4.6 mm (38%) in the epiphysis and 7.5 mm (62%) in the neck and diaphysis. Mean femoral shortening in piglets sacrificed at 20 weeks after operation was 20.7 mm. The distribution of shortening was 4.0 mm (19%) in the epiphysis and 16.7 mm (81%) in the neck and diaphysis.

We determined the proportional contribution to the residual shortening according to the causative factors.