Infection-related atlantoaxial subluxation (Grisel syndrome) in an adult with Down syndrome.

STUDY DESIGN: Case report.

OBJECTIVE: To report an adult case with Down syndrome, in whom infection-related atlantoaxial subluxation (Grisel syndrome) developed.

SUMMARY OF BACKGROUND DATA: Atlantoaxial instability is a common complication in Down syndrome patients; however, there have been limited reports of adult-onset atlantoaxial subluxation with myelopathy. Grisel syndrome has been characterized as a nontraumatic atlantoaxial subluxation associated with pharyngeal infection. It usually affects children, and the subluxation can be successfully reduced by conservative treatments in most cases.

METHODS: A 26-year-old man with Down syndrome suffered from retropharyngeal infection, after which his atlantoaxial subluxation was aggravated and myelopathy developed. He was treated with administration of antibiotics and application of a halo-vest.

RESULTS: The conservative treatments failed to reduce the atlantoaxial subluxation. We performed a C1 laminectomy and posterior occipitocervical fusion, which successfully relieved his symptoms. CONCLUSION.: This experience suggests that when Down syndrome patients have retropharyngeal infection, we should consider the possible aggravation of atlantoaxial instability and development of myelopathy, even if the patient is an adult.