Abstract
Fibrous dysplasia (FD) is a rare skeletal disorder characterized by the replacement of normal bone with fibrous connective tissue, leading to abnormal bone formation. This case report details the successful treatment of a 61-year-old woman with FD at the craniovertebral junction (CVJ). The patient, who had a history of intracranial meningioma and had already been diagnosed with FD, experienced worsening gait disturbance and muscle weakness following a fall. Imaging studies revealed extensive polyostotic FD lesions in the skull and cervical spine, along with a C2 odontoid fracture causing spinal cord compression. The patient underwent occipitocervical fixation and decompression surgery. Intraoperative O-arm navigation was used to ensure accurate screw placement and effective decompression. This procedure allowed for proper positioning of the C2 and C3 pedicle screws, resection of the hyperplastic occipital bone and C1 posterior arch, and placement of the occipital plate with avoiding the cyst components. At a 2-year follow-up, there were no signs of screw loosening, and the patient showed marked clinical improvement. This case emphasizes the importance of tailored surgical strategies and the use of advanced navigational technologies in managing complex FD cases, particularly those involving the CVJ. It also highlights the challenges of treating polyostotic FD, where complete resection is often unfeasible. The successful outcome in this case supports the use of decompressive surgery combined with stabilization to relieve symptoms and prevent further complications.