ODONTOID PROCESS AND C1-C2 CORRECTIVE OSTEOTOMY THROUGH A POSTERIOR APPROACH - TECHNICAL CASE-REPORT

OBJECTIVE AND IMPORTANCE: To demonstrate a new posterior approach to t he anterior elements of the atlas and the axis including the odontoid process. CLINICAL PRESENTATION: A 36-year-old woman presented with ank ylosing spondylitis and severe flexion deformity of the cervical spine . She had sustained a trauma 5 years previously, causing the inability to look forward or to open the jaw adequately. An examination demonst rated fixed flexion and rotation of the cervical spine, with no neurol ogical deficit. Radiologically, there was fusion of C1, C2, and the cl ivus. TECHNIQUE: The upper cervical vertebrae were exposed via a midli ne posterior incision, the posterior arch of C1 was excised, and the v ertebral arteries were mobilized. A wedge osteotomy was performed thro ugh the lateral masses of C1 and subsequently through the odontoid. Th e head was repositioned, and C1-C2 lateral mass screws and a Ransford loop were inserted. CONCLUSION: It is possible to gain sufficient surg ical access to the odontoid process via a posterior approach. The tech nique described is of benefit when the alternative anterior approaches to the upper cervical spine are technically difficult or impossible.