Pathogenesis of ischemic necrosis of the femoral head.

There are several potential pathways by which bone dies, one or more of which may be operative in any given case. However, the compartmental nature of its circulation renders bone vulnerable to ischemia from a primary elevation of BMP due to increase in any of the tissues within bone and outside the vessels. Furthermore, ischemia from other primary sources may be potentiated by a secondary increase in BMP. Findings of elevated BMP in the preradiologic and even preclinical stages of INFH support this pathogenetic hypothesis. The long-term results of core decompression reported by Professor Ficat lend further credence to these concepts.