Revascularization of the femoral head. A clinical and experimental study.

Most large long-term follow-up studies of displaced femoral neck fractures treated by internal fixation show a 20-35 per cent late collapse of the femoral head. Clinical observations on factors such as age, time of collapse and isotopic evidence of bone turnover, seem to indicate that a strong revascularization potential may be more harmful than helpful. Experiments on completely devascularized femoral heads in dogs reveal that those allowed to revascularize showed creeping "osteoporosis" with partial or complete collapse in almost 50 per cent of the hips. Those canine femoral heads prevented from revascularizing showed much less osteoporosis and collapse, and the articular cartilage seemed to survive and function adequately for the 2 1/2 year duration of the experiment.