Spine Surgery, Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008, China.
This study is an investigation into the position of the cerebellar tonsils in AIS with severe curves and any relationship it has with age, sex, curve severity and curve pattern. Sagittal magnetic resonance imaging (MRI) of hindbrain was performed on both of 205 AIS patients with a Cobb angle greater than 40 degrees and 86 healthy controls. The position of the cerebellar tonsil relative to the line connecting the basion and opisthion (BO line) was measured. In AIS and controls, the mean position of the cerebellar tonsil was 0.9 and 2.9 mm above the BO line, respectively. The incidence of tonsillar ectopia in AIS was found to be significantly higher than controls (34.5% versus 5.8%, p<0.001). No significant correlations were found between the position of the cerebellar tonsil with age or sex in AIS and controls. It was shown the position of the cerebellar tonsil was not significantly different among AIS patients with deferent curve severity. However, a significant lower incidence of tonsillar ectopia (p=0.049) was found in patients with lumbar curves when compared to those with thoracic or thoracolumbar curves. In conclusion, there was a relatively lower position of the cerebellar tonsil together with a significant higher incidence of tonsil ectopia in AIS patients. There was a trend that tonsillar ectopia was more often in thoracic or thoraco-lumbar curves, suggesting that a lower position of the cerebellar tonsil may play an important role in the etiopathogenesis of AIS.
This study has significant implications for the unilateral rotation dysfunction of scoliosis. As the coiling of the spine increases so does the torquing pull of the nerve roots onto the spinal cord which then tugs on the brainstem and pulls the cerebellum through the foreman magnum. As scoliosis curves progress, so does the torque to the spinal cord, thus worsening the condition.
De-rotating the spine becomes essential for the return of health to the nervous system as well as for the correction of scoliosis curves themselves. These findings have also been confirmed in Atlas Orthogonal work that examines the exact relationship between the occiput, atlas and axis of the upper cervical spine. Dis-relationship between these three vertebra can cause significant torsional rotation forces to the spinal cord and brainstem which may be a major causation for scoliosis. In fact, recent studies have shown that by accurately re-establishing the relationship between the atlas and occiput using the Atlas Orthogonal method alone showed a significant improvement in the scoliosis curves has occurred.
The question becomes one of the “Chicken and the Egg”. Which came first, the torque to the brainstem by the dis-relationship of the atlas and occiput or is this torque to the brainstem and cerebellum due to the overall torque of the collapsing rotational dysfunction caused by unilateral rotation dysfunction of the spine and it’s associated structures.
Further research is needed into this notable phenomenon but one thing is for sure. There is a rotational dis-relationship present in the spinal structures that must be addressed to normalize a spine with scoliosis.