 The microscopic features are similar to those of ischaemic or aseptic osteonecrosis of long bones, corticosteroid-induced osteonecrosis, and the osteomyelitis of caisson (deep-sea diver's) disease"".In the cancellous portion of femoral head it is not uncommon to find trabeculae with apparently intact osteocytes which seem to be "alive" but are no longer synthetizing collagen.This appears to be consistent with the findings in alveolar cancellous bone.