Intracranial erosion of an occipitocervical rod through the foramen magnum following occipitocervical fusion for retro-odontoid pannus: illustrative case.

Intracranial rod erosion after OCF is rare but should be suspected in the presence of wound breakdown, new posterior fossa symptoms, or construct instability. Prevention requires meticulous rod contouring to avoid occipital contact, secure cranial fixation, and early postoperative surveillance. Management benefits from multidisciplinary collaboration and intraoperative ultrasound for safe extraction in anatomically constrained regions. https://thejns.org/doi/10.3171/CASE25837.