How is atlantoaxial C1 C2 instability diagnosed?
Instability of C1 to C2 is diagnosed when the interval between the odontoid process and the anterior arch of the atlas is >3 mm on lateral flexion and extension radiographs. This indicates that the transverse ligament has been compromised. When the interval exceeds 7 to 8 mm, it is likely that the alar ligaments are compromised as well, significantly increasing the risk of spinal cord compromise.
How is atlantoaxial C1 C2 instability managed?
Patients with symptoms attributable to C1 to C2 instability should have surgical stabilization performed prior to elective surgery. Patients with asymptomatic or mild disease may be considered for intubation with fiberoptic assistance to minimize the extremes of motion associated with routine intubation. A soft cervical collar worn throughout the perioperative period will serve as a visual reminder that these patients should be handled with care, but it does not offer support to an unstable spine