Non-traumatic atlanto-axial subluxation in an 8-year-old child.

An 8-year-old child with a previous history of neonatal retropharyngeal abscess presented with a 6-month history of progressive quadriparesis. Investigations demonstrated atlanto-axial subluxation with anterior displacement of the odontoid peg to a position anterior to the vertebral body of C2. Magnetic resonance imaging confirmed severe neural compression at this level. The child was placed in a halo fixation device and underwent transoral removal of the odontoid peg together with the upper part of the body of C2. At a subsequent procedure a posterior occipito-cervical fusion was performed. The aetiology and management of this case are discussed.