Avascular (aseptic) necrosis of bone
Chapter: 26
Bone infarcts resulting from occlusion of small vessels, usually at the ends of the long bones, produce multiple subarticular bone defects. Pathogenesis Nitrogen embolization in divers with caisson disease fat emboli, in transplant and other patients on steroids for immunosuppression, idiopathic in Perthe disease (avascular necrosis of the femoral head), and osteochondritis dessicans (subarticular infarcts in a variety of weight-bearing bones).