Operative video of Goel-Harms C1-C2 fusion for atlanto-axial instability secondary to odontoid fracture (Anderson-D' Alonzo II).

Background: Type II odontoid fractures are the most common unstable injuries of the upper cervical spine. They are associated with high non-union rates, particularly when accompanied by ligamentous disruption and/or fracture displacement. Posterior C1-C2 fixation using the Goel-Harms technique provides immediate biomechanical stability, high fusion rates, and reduces the risk of a neurovascular injury when compared with transarticular fixation. Case Description: A 33-year-old male sustained polytrauma after a fall from >3 m. The initial evaluation revealed a severe traumatic subarachnoid hemorrhage with additional complex craniovertebral junction instability. The cervical computed tomography and magnetic resonance imaging scans demonstrated an unstable Anderson- D'Alonzo type II odontoid fracture accompanied by posterior displacement of the dens up to 5 mm into the spinal canal, occipitocervical dissociation, and rupture of the transverse and alar ligaments. Despite severe radiographic instability, no spinal cord injury was identified. Anterior odontoid screw fixation was contraindicated in this case due to the fracture morphology and extent of ligamentous disruption. Rather, we chose to perform the Goel-Harms atlantoaxial stabilization technique utilizing C1 lateral mass and C2 transpedicular screw fixation. Adequate intraoperative reduction and restoration of alignment were achieved without neurovascular complications. Postoperatively, the patient remained neurologically intact, pain significantly improved, and stable fixation was achieved as documented on appropriate postoperative imaging. Conclusion: In this surgical video, the authors successfully performed Goel-Harms C1 lateral mass and C2 transpedicular screw fixation to stabilize a type II odontoid fracture associated with ligamentous injury and craniovertebral instability.