Instrumentational posterior fusion for atlanto-axial subluxation in a young child with Down's syndrome--case report.

A 3-year-old girl with Down's syndrome and myelopathy caused by atlanto-axial subluxation (AAS) was treated by C-1 to C-2 posterior fusion with a one-piece cervical device (OPCD). Instrumentation was required because the posterior arch of C-1 was too tiny and fragile to tolerate wiring. Postoperative immobilization was another major problem in this mentally retarded young child, but a hard plastic cervical corset effectively restrained the neck. She had been confined to bed by severe quadriparesis, but became able to walk without assistance 8 months after surgery. We recommend OPCD instrumentation and postoperative immobilization using a hard plastic corset for the treatment of AAS associated with Down's syndrome in young children.