Atlantoaxial Traumatic Ligament Disruption

• If there is an ADI of >4.5 mm this implies ligamentous compromise
• Isolated transverse atlantoaxial ligament instability is rare in normal children
• However, it may occur frequently in Down’s syndrome, RA, Larsen syndrome, & bony dysplasia including mucopolysaccharidosis & various dwarfism
• Bony abnormality including Klippel Feil syndrome may be associated with instability
• Goldenhar & Apert syndrome may be associated with instabilty

History

• Above patients may be predisposed
• Cranial nerve, long tract signs & sphincter dysfunction, gait abnormality

Treatment

• acute injury should be immobilized in extension, followed by posterior fusion of C1 ro C2 using a Halo postoperatively
• Chronic situation including Down’s wait upto 10 mm of displacement or SAC < 13 mm stabilization is indicated
• If there is a < 10 mm ADI but the physical or history is suggestive of embarrasment then fuse
• Fusion is typically sublaminar BUT no sublaminar wires if the patient does not reduce
• If the Down’s ADI is greater than 4.5 mm should restrict the child from contact sport/trauma