Radiographic predictive findings of neck pain in patients with ankylosing spondylitis.

OBJECTIVE: The aim of this study was to investigate the relationship between neck pain and radiological findings in ankylosing spondylitis (AS) patients. METHODS: The study groups comprised 257 AS and 50 normal patients. Of the AS patients, 91 had axial neck pain (group 1) and 166 did not (group 2). Full-length radiographs of the spine in the anteroposterior and lateral planes were taken. Radiographic parameters such as the chin brow vertical angle (CBVA), McGregor slope (McGS), slope of the Line of Sight (SLS), C2 slope, C2-C7 lordosis (CL), C2-C7 sagittal vertical axis (C2-C7 SVA), and T1 slope were measured. Statistical analysis was performed. RESULTS: The AS and normal patients were found to have significantly different CBVA, McGS, C2 slope, C2-C7 SVA, and T1 slope. However, no significant difference was observed for SLS and CL. Between groups 1 and 2, there were significant differences in the McGS, CL, and T1 slope. However, no significant difference between these two groups was observed for CBVA, SLS, C2 slope, and C2-C7 SVA. Logistic regression analysis was performed to identify statistically significant predictors of neck pain in AS patients and it revealed that the T1 slope and McGS were two such predictors. The T1 slope showed superior discriminatory power to McGS and CL in the receiver operating characteristic curve analysis. CONCLUSIONS: This study shows that a high T1 slope and McGS are independent radiological predictors of neck pain in AS. Further well-designed studies would be necessary to substantiate our results.