Background <p>Traumatic atlanto-occipital dislocation (AOD) is a rare, high-energy injury of the craniocervical junction, typically resulting in severe trauma. Due to the involvement of the cervicomedullary junction, AOD often proves fatal or leads to profound neurological impairment, with extremely low survival rates. In this study, we present an extremely rare case of posterior AOD and anatomical reduction and complete decompression was successfully achieved through atlanto-occipital fixation (atlanto-occipital condyle) and fusion.</p> Case presentation <p>A 56-year-old male complained of pain in occipitocervical area with restricted neck movement. Imaging investigation confirmed the posterior AOD accompanied by a right occipital condyle fracture. After 3 days of traction, three-dimensional computed tomography (CT) reconstruction demonstrated partial reduction in the right atlantooccipital joint, whereas no reduction was observed on the left side. Subsequently, atlanto-occipital fixation (atlanto-occipital condyle) and fusion were performed, achieving anatomical reduction and complete decompression in the craniocervical junction.</p> Conclusion <p>Atlanto-occipital condyle fixation and fusion can achieve anatomical reduction while preserving atlanto-axial mobility. Although freehand screw placement in the occipital condyle is technically challenging, the procedure represents a viable surgical option in select patients with isolated C0–C1 instability.</p>