Is rheumatoid arthritis a risk factor for a high-riding vertebral artery?
STUDY DESIGN: A retrospective comparative study on the morphologic characteristics of the axis in patients with or without rheumatoid arthritis (RA). OBJECTIVE: To compare the morphologic risk of vertebral artery (VA) injury during atlantoaxial transarticular screw fixation between patients with or without RA. SUMMARY OF BACKGROUND DATA: VA injury is a potentially serious complication during atlantoaxial transarticular screw fixation. Although this operation is frequently performed on RA patients, there have been few comparative studies on the morphologic risk of VA injury between RA and non-RA patients. METHODS: A total of 107 three-dimensional computed tomography images of the cervical spine including the C1-C2 complex were evaluated. Forty-seven RA patients and 60 non-RA patients were included in the study. The maximum atlantoaxial transarticular screw diameter (MSD) that could be inserted without breaching the cortex was measured 3-dimensionally using a computer- assisted navigatio
