C2 rotation and spinous process deviation in migraine: cause or effect or coincidence?

Previous reports have shown an association between the side of C2 spinous process deviation or asymmetrical prominence, or vertebral rotation, and the side of the headache in unilateral migraine. However, this study has found that such C2 appearances were present as frequently in the controls as in the migraine patients, and that there was no association between the side of the anomaly and the lateralisation of the headache. The results were comparable for the different sub-groups of migraine.