- Flat vertebral bodies: The vertebrae are flattened and bullet shaped (platyspondyly).
- Thick ligament at C1: There is ligamentous thickening behind the odontoid process, which may extend further down the cervical spinal canal.
- Stenotic canal: The spinal canal is narrowed, particularly adjacent to regions of increased motion, e.g., the craniovertebral junction and midcervical spinal canal.
- Thoracolumbar gibbus: This condition is common and often requires instrumented stabilization.
While craniovertebral changes occur in mucopolysaccharidoses types I, II, and VI, patients with Morquio syndrome (type IV) are at particular risk from the combination of these morphological changes and instability (32, 33).
- Dysplasia of the cervical spine: Odontoid hypoplasia, incomplete C1 ring formation, and platyspondyly are common features.
- Pannus formation: Soft tissue thickening behind odontoid process (“pannus”) is apparent.
- Spinal canal stenosis