Effect of hip dislocation on the blood supply to the femoral head. An experimental study in rabbits.

This work consists of a series of experiments which were made in order: a) to examine the possible alterations of blood flow to the reduced femoral heads of rabbits, after inducing a closed dislocation of their hips and b) to determine the influence of the early or late reduction of the dislocated femoral heads on their blood flow. The estimations of blood flow to the normal and reduced femoral heads were made using radioactive microspheres. The findings are as follows: a) The blood flow of the femoral heads of the reduced hips was never interrupted completely. b) The initially decreased femoral head blood flow progressively increased, in association to the time elapsed from the reduction. c) No statistically significant difference was found in the femoral head blood flow between hips reduced in early and those reduced late. d) Pure traumatic dislocation of the hip can only rarely be the cause of aseptic necrosis of the femoral head.