Aneurysmal bone cyst
 Discussion of Aneurysmal bone cyst
- An aneurysmal bone cyst is an expansile lesion that contains blood-filled cystic cavities.
- Several hypotheses have been proposed with respect to its pathogenesis. Altered hemodynamics secondary to a coexistent lesion or a traumatic injury seems to be a common denominator.
- In aneurysmal bone cyst, the patient age is typically less than 20 years.
- The male-to-female ratio is 1.2:1.
- Patients typically experience pain and swelling.
- Aneurysmal bone cysts are a component of, or arises within, a preexisting bone tumor in about one third of cases.
- Preexisting lesions include:
 Imaging Findings for Aneurysmal bone cyst
- Aneurysmal bone cysts are well-defined, cortically based, rapidly expansile lytic lesions.
- The location is usually metaphyseal, and the epicenter is eccentric.
- Long tubular bones and the spine account for 60%–70% of cases.
- They can grow large enough to involve the medullary cavity, although their tendency is for eccentric expansion (a so-called blister lesion).
- Extremely rapid growth is characteristic of aneurysmal bone cysts, as expansion has more to do with vascular engorgement than with cellular proliferation, and aids in its differentiation from other eccentric, expansile lesions of bone.
- Must be differentiated from telangiectatic osteosarcoma.
Patient #1: Radiograph demonstrates an aneurysmal bone cyst in the hand
Patient #2: Radiograph demonstrates an aneurysmal bone cyst in the proximal humerus
 See Also
 External Links
 References for Aneurysmal bone cyst
- Scott M. Levine, Robert E. Lambiase, and Catherine N. Petchprapa. Cortical Lesions of the Tibia: Characteristic Appearances at Conventional Radiography. RadioGraphics 2003 23: 157-177.
- E-medicine Aneurysmal bone cyst article.