Transoral resection of a symptomatic odontoid process aneurysmal bone cyst: illustrative case.

backgroundAneurysmal bone cysts (ABCs) are slow-growing, expansile bone tumors most often observed in the long bones and lumbar and thoracic spine. Anterior column ABCs of the spine are rare, and few cases have described their surgical management, particularly for lesions with extension into the odontoid process and the bilateral C2 pedicles. In the present case, the authors describe a two-stage strategy for resection of a symptomatic 2.3 × 3.3 × 2.7-cm C2 ABC with cord compression in a 13-year-old patient. OBSERVATIONS: Initial tumor debulking was completed via a transoral approach, and resection of the involved region spanning the odontoid process to the C2-3 disc space was continued until visualization of the posterior longitudinal ligament. After appropriate decompression was confirmed, the patient was repositioned prone for removal of the residual tumor among the bilateral C2 pedicles. Posterior instrumentation was placed from the occiput to C4, with an autologous rib graft to encourage fusion. The postoperative recovery was uneventful, and 2-month imaging demonstrated postsurgical changes, resolution of compression, and a stable position of the instrumentation and graft material. LESSONS: The transoral approach facilitates sufficient exposure for the resection of large odontoid ABCs, and posterior stabilization can reduce the risk of postsurgical cervical subluxation. https://thejns.org/doi/10.3171/CASE2485.