MedGen

Aneurysmal bone cysts are benign primary or secondary lesions that are rapidly expansive and locally destructive. They are located in the posterior elements of the vertebral column or the flat or long bones of patients under 30 years of age. The cysts are blood-filled and separated by septa containing spindle cells, trabeculae of bone, and osteoclastic giant cells (Biesecker et al., 1970). Histopathologically and radiographically, aneurysmal bone cysts are similar to telangiectatic osteosarcoma from which they must be differentiated. [from OMIM]