Aneurysmal bone cyst of thoracic spine with neurological deficit and its recurrence treated with multimodal intervention - A case report

Background: Aneurysmal bone cysts (ABCs) are rare, representing about 1% of primary bone tumors, and 15% of all primary spine/sacral tumors. Notably, when they are located in poorly accessible regions such as the spine and pelvis, their management may be challenging. Treatment options include selective arterial embolization (SAE), curettage, en bloc excision with reconstruction, and radiotherapy.

Case description: A 16-year-old male presented with 2 months of mid back pain, left-sided thoracic radiculopathy, and left lower limb weakness (MRC - 3/5). MR imaging revealed an expansile, lytic lesion involving the T9 vertebral body, and the left-sided posterior elements resulting in cord compression. He underwent SAE followed by intralesional excision, bone grafting, and a cage - instrumented fusion. ABC was diagnosed from the biopsy sample. Postoperatively, the pain was reduced, and he was neurologically intact. Five months later, he presented with a new lesion that was treated with repeated SAE and three doses of zoledronic acid. At the end of 2 years, the subsequent, MRI and CT studies documented new bone formation in the lytic areas, with healing of lesion; additionally, he clinically demonstrated sustained pain relief.

Conclusion: Here, we emphasized the importance of surgery for patients with ABC who develop focal neurological deficits. Treatment options should include SAE with bisphosphonate therapy for lesions that recur without neurological involvement.

Keywords: Aneurysmal bone cyst; Bisphosphonate therapy; Recurrence; Selective arterial embolization; Surgical excision.