Surgical management of Grisel syndrome in the adult patient: illustrative case.

backgroundGrisel syndrome describes an infectious soft tissue process that destabilizes the cervical bony elements and ligamentous complexes. This nontraumatic atlantoaxial rotary subluxation occurs in children primarily. This case illustrates a rare case presentation of an adult with Grisel syndrome: infectious destruction of the right atlantoaxial facet joint caused the occiput-C1 vertebra (head) to rotate rightward with lateral horizontal displacement off the C2 vertebra. OBSERVATIONS: Because the infection destroyed the C1 bony arch and atlantoaxial facet joints with epidural extension, the rotated head and atlas pulled the brainstem-cervical spinal cord junction against a fixed odontoid process, resulting in a cord contusion. Because of the highly unstable craniocervical junction, the patient presented with torticollis and left upper extremity weakness. LESSONS: Treatment entailed closed reduction under general anesthesia followed by occipitocervical fusion with an occipital plate, C1 lateral mass screws, and C2-C5 pedicle screws. This case describes the unique surgical pearls necessary for occipitocervical fusion of an unstable craniocervical junction, including tips with neuronavigation, trajectories of the cervical pedicle screws, aligning the lateral mass and pedicle screws with the occipital plate, and nuances with occipitocervical distraction.