Chronic atlantoaxial rotatory fixation with neurofibromatosis type I: A case report.

Background: Atlantoaxial rotatory fixation (AARF) can be caused by infection, rheumatoid arthritis, surgery of head and neck, and congenital diseases. Type 1 neurofibromatosis (NF-1) is often associated with various musculoskeletal diseases, but few reports have described AARF with NF-1. Here, we report the success of a closed reduction and halo fixation utilized to treat chronic AARF with NF-1 in a 7-year-old female.

Case Description: A 7-year-old female with NF-1 presented with a 2-month history of torticollis and neck pain. C2 facet deformity had previously been identified on computed tomography (CT) before the onset of neck pain. Cervical radiography and CT showed AARF classified Fielding's Type I and Ishii's Grade II. Following 2 weeks of cervical traction, a closed reduction was followed by halo fixation that was utilized for 2 months. The patient fully recovered cervical range of motion following halo vest removal 4 months later. Further, the follow-up CT documented a normal atlantoaxial joint despite residual C2 facet deformity. In addition, no recurrence was evident 2 years later.

Conclusion: Halo fixation for chronic AARF with NF-1 proved effective. C2 facet deformity associated with NF-1 might have contributed to the onset of AARF.