Bone sarcomas associated with multifocal medullary bone infarction in dogs.

Nine dogs with primary osteosarcoma also had concurrent bone infarctions. The median weight of the 9 dogs was less than 12 kg, and the median age was 10 years. Radiographically and histologically, bone infarctions were apparent in the limb bones and the cranium. Radiographically, there were multiple, irregular intramedullary densities, particularly in the limb bones. Histologically, there was widespread necrosis of the medullary soft tissue and bone, with proliferative new bone formation on medullary trabeculae. Collagen deposition throughout the vessel walls leading to occlusion was seen only in the intramedullary arteries.