A case report of revision occipital-cervical fusion after atlanto-axial instrumentation failure for neurofibromatosis type I

BACKGROUND: Neurofibromatosis type 1 is an autosomal dominant genetic disease with characteristic café-au-lait spots, neurofibroma, and dystrophic changes in the bones. However, complications involving atlanto-axial dislocation are rare. CASE PRESENTATION: We report a case of neurofibromatosis with atlanto-axial dislocation. The chief complaints were numbness of the upper limb and gait disturbance. We performed short fusion using the Brooks method. However, recurrence of the dislocation was found after 5 months recovery, and the patient underwent posterior fusion from the occipital bone to C4. Thereafter, she had a good postoperative course. CONCLUSIONS: Neurofibromatosis patients often exhibit a low bone mineral density because of dystrophic changes, and are prone to fragile bones. In the present case, the use of long fusion at the first surgery may have helped to form a strong fusion of fragile bone.