Skeletal anomalies of the upper cervical spine in children with Down syndrome.

This study showed that a significantly greater number of children with Down syndrome (45 to 78) have cervical spine anomalies than an age- and sex-matched group of normal children (3 of 38). Moreover, children with Down syndrome who had atlantoaxial instability had an increased frequency of cervical spine anomalies (31 of 39) as compared with an age- and sex-matched group of children with this chromosome disorder who did not have atlantoaxial instability (14 of 39).