Associations
- Morquios
- Spondyloepiphyseal dysplasia
- Achondroplasia
- Downs- 25% have instability
- Pharyngeal infection in the normal child (= Grisels syndrome)- due to hyperaemia causing demineralisation of the attachment of the transverse ligament to the anterior arch of the atlas
- rotatory subluxation or anterior subluxation
Atlanto Dens Interval
- more than 5mm = instability
- more than10mm = indication for surgery
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.