Venous drainage of the femoral neck in Legg Perthes disease and in hip dysplasia. A clinical and experimental study in the dog and pig.

Three clinical cases of canine avascular femoral head necrosis and 4 cases of hip dysplasia were examined using intraosseus femoral neck venography. The contrast medium passed initio the diaphyseal bone marrow in all cases. Three growing dogs and 7 growing pigs were examined with the same method, before and after experimental ligation of the femoral veins. Before the venous tamponade, no contrast medium was visible in the femoral neck. The venography performed immediately after ligation showed contrast flow into the femoral neck similar to that seen in the clinical cases of Legg Perthes disease or hip dysplasia. However, a collateral circulation developed within 7 weeks. No more contrast-flow into the diaphysis was observed after that time. Although osteomedullography shows that both in Perthes disease and in hip dysplasia venous drainage has failed, venous tamponade may not induce the onset of the disease.