Endoscopic Image-Guided Transcervical Odontoidectomy: Outcomes of 15 Patients With Basilar Invagination

BACKGROUND: Ventral decompression with posterior stabilization is the preferred treatment for symptomatic irreducible basilar invagination. Endoscopic image-guided transcervical odontoidectomy (ETO) may allow for decompression with limited morbidity. OBJECTIVE: To describe the perioperative outcomes of patients undergoing anterior decompression of basilar invagination with the use of ETO. METHODS: Fifteen patients who had a follow-up of at least 16 months were retrospectively reviewed. Intraoperatively, the vertebral body of C2 was removed and the odontoid was resected in a "top-down" manner using endoscopic visualization and frameless stereotactic navigation. Posterior instrumented stabilization was subsequently performed. RESULTS: The average (+/- standard deviation) age of the patients was 42.6 +/- 24.5 (range, 11-72) years. Postoperative complications occurred in 6 patients, including a urinary tract infection (n = 2), upper airway swelling (n = 2), dysphagia (n = 2), gastrostomy tube placement (n = 1), and an asymptomatic pseudomeningocele (n = 1). No patients required a tracheostomy, had bacterial meningitis, or developed a venous thromboembolic event; only 1 patient was intubated for more than 48 hours post-operatively. With a mean follow-up of 41.9 +/- 14.4 (range, 16-59) months, myelopathy improved in all patients and no patient experienced late neurological deterioration. The mean modified Japanese Orthopedic Association (JOA) score increased from 11.2 +/- 4.2 to 15.9 +/- 1.4 (P = .002). Patients with a diagnosis other than rheumatoid arthritis or who had a higher preoperative JOA score had a significantly better postoperative neurological recovery (P = .005). CONCLUSION: ETO may be a valid treatment for patients with symptomatic irreducible basilar invagination that avoids some of the morbidity of transoral surgery and leads to long-term improvement in myelopathy.