Aneurysmal Bone Cyst Wheeless

Description: - non-neoplastic expansile lesion consisting of blood filled spaces separated by connective tissue septa containing bone or osteoid and osteoclast giant cells - etiology unknown - may be primary or secondary; - an uncommon expansile osteolytic lesion of bone consisting of a proliferation of vascular tissue that forms a lining around blood filled cystic lesion; - it develops in metaphyseal region of long bones, pelvis, vertebral posterior elements; - it commonly involves the proximal humerus, femur, tibia, and pelvis;