Safeguarding the Anomalous Vertebral Artery While Dissecting, Drilling, and Instrumentation of C1-2 Joint for Congenital Atlantoaxial Dislocation: 2-Dimensional Operative Video

The pathology in congenital atlantoaxial instability is usually in C1-2 joints. Addressing the joints appears to be the most rationale approach. The joints are usually approached posteriorly, manipulated, and fused. Understanding the normal and abnormal anatomy is important. Normally, the third segment of the vertebral artery courses lateral to the C1-2 joint. However, in about 20% of the cases with complex congenital craniovertberal junction anomalies the artery crosses the joint posteriorly. The artery in such cases may be injured while joint manipulation and instrumentation with disastrous consequences. Alternatively, occipital squama can be fused to the cervical spine. However, this requires fusion of multiple segments affecting the neck movements significantly. An anomalous vertebral artery can be dissected, mobilized, and safeguarded while dissecting, manipulating, and fusing the C1-2 joint. In this operative video, authors have highlighted the technique to safeguard the anomalous vertebral artery during joint manipulation. Proper informed consent was obtained from the patient.