IS Case 595: Aneurysmal bone cyst (ABC) within the talus

Nadia F. Yusaf, MD

Imaging Sciences URMC

Imaging Sciences URMC 2010
Publication Date: 2011-11-17

History

Patient is a 21-year-old female with a bump on her ankle that has been present for four years. She has some pain, rated a four out of ten.

Patient is a 21-year-old female with a bump on her ankle that has been present for four years. She has some pain, rated a four out of ten.

Aneurysmal bone cyst (ABC) within the talus

An aneurysmal bone cyst (ABC) is an expansile lesion with thin-walled blood filled cysts. Usually, patients present in the first through third decades of life with pain and swelling for weeks to years. ABCs are mostly found in long tubular bone metaphyses or in the spine. On radiographs, osteolysis and expansion are predominant features. In tubular bones, there is cortical thinning, expansion, thin trabeculation, periosteal reaction, and pathologic fracture. In the spine, the lesion involves the posterior elements or the posterior elements and the vertebral body. In other site, soft tissue extension may make it hard to differentiate ABC from sarcoma. CT and MRI can demonstrate fluid levels within the lesion. These lesions do have potential for growth, bone destruction and soft tissue invasion so they are treated surgically or with radiotherapy.