Aneurysmal bone cysts: Case report and literature review

Background: Aneurysmal bone cysts (ABC) are benign lesions with great vascularization and expandability. They represent approximately 1% of all bone tumors. These lesions are characterized by having multiple cavities filled with blood. In most cases, they are located in the thoracic and lumbar region. In this article, we aimed to present a clinical case and followed by review of relevant literature regarding pathophysiology, clinical, diagnostic and therapeutic aspects of this pathology. Case presentation: A 41-year-old woman came with chief complaint of developing pain in the left hip, right gluteal region, and right posterior thigh for last 10 months. We performed hip plain x-ray, which suggested a left hip injury. Further investigation using computed tomography and magnetic resonance imaging were performed and revealed tumor of the left hip. A biopsy guided by TAC was performed. The histopathologic examination revealed numerous small vascular spaces lined with endothelial cells, abundant pools of red blood cells were seen, and hemosiderin pigment was seen at places along with giant cells, which was suggestive of ABC. Conclusion: Aneurysmal bone cysts are lesions that represent a small percentage of the total osseous tumors. Sacral localization is rare and the manifestations are nonspecific.