Endonasal Endoscopic Resection of an Os Odontoideum to Decompress the Cervicomedullary Junction A Minimal Access Surgical Technique

Study Design. We report the case of a 50 year-old woman with os odontoideum and posterior atlantoaxial subluxation, who underwent an occipitocervical fusion followed by endonasal endoscopic anterior decompression of the cervicomedullary junction (CMJ). Objective. To describe the feasibility of performing endonasal endoscopic anterior decompression of CMJ pathology in conjunction with occipitocervical fusion in 1 operative setting. Summary of Background Data. The recommended management of symptomatic atlantoaxial instability secondary to os odontoideum with irreducible ventral compression is occipitocervical fusion with anterior decompression. The traditional method for anterior decompression of CMJ abnormalities is the transoral approach. The endonasal endoscopic approach is an emerging minimal access technique that reduces the potential morbidity of the transoral approach. Methods. The patient underwent an occipitocervical fusion and anterior decompression in 1 operative setting. Occiput to C5 fusion was first undertaken in the prone position. After a wake-up test, the patient was flipped into a supine position for the endonasal endoscopic procedure. Anterior decompression was achieved by resecting the anterior arch of C1 and the os odontoideum with the aid of frameless stereotactic navigation. Results. The patient tolerated the procedure well and was extubated on the first postoperative day. Liquids were started that afternoon and advanced to a regular diet on the second postoperative day. The patient was discharged to rehabilitation after a short postoperative stay. Postoperative imaging demonstrated excellent decompression of the anterior CMJ pathology. At 3-month follow-up, the patient showed clear improvements in hand strength and ability to ambulate. Conclusion. The endonasal endoscopic approach to the CMJ provides an effective and minimally invasive alternative for anterior decompression of irreducible CMJ pathology.