Eleven patients with documented Morquio's syndrome who had dysplasia of
the odontoid process and resulting atlanto-axial instability were reviewed.
They were found to be at risk for acute traumatic quadriparesis, chronic
myelopathy of a variable and often rapid rate of progression, and sudden
death by respiratory arrest. The evidence suggests that early prophylactic
posterior cervical fusion is indicated for patients with this malformation
and that once quadriparesis is established, recovery of function is
limited.