Do Cervical Parameters Increase the Risk of Thoracic Spinal Stenosis in Patients with Cervical Spinal Stenosis?

The diagnosis and treatment of tandem stenosis have been widely discussed. However, studies on concurrent cervical and thoracic spinal stenosis are rare in the literature. This study was aimed to investigate the risk factors for thoracic spinal stenosis (TSS) in patients with cervical spinal stenosis (CSS). This retrospective cohort study assessed the risk factors for TSS in 162 patients who were diagnosed with CSS. Patients were divided into TSS (n = 45) and non-TSS (n = 117) groups. We retrospectively analyzed clinical characteristics and radiographic parameters including age, gender, body mass index, ossification of the cervical posterior longitudinal ligament (OPLLc), hypertrophy of cervical ligamentum flavum (HLFc), cervical stenosis segments, and cervical sagittal parameters. Cervical sagittal parameters were measured on T2-weighted magnetic resonance imaging including C2-7 Cobb angle, cervical tilt, T1 slope, thoracic inlet angle (TIA), C2–C7 sagittal vertical axis (C2–C7), and cervical curvature. Two groups showed significant differences in ossification of the cervical posterior longitudinal ligament, HLFc, cervical stenosis segments, and TIA. The receiver operating characteristic curves demonstrated that the optimal threshold for TIA was 68.25. In multivariate logistic regression analysis, OPLLc (odds ratio [OR] = 4.403, 95% confidence interval [CI] = 1.782–10.880, P = 0.001), HLFc (OR = 4.849, 95% CI = 1.995–11.782, P < 0.001), and TIA >68.25 degrees (OR = 2.555, 95% CI = 1.044–6.251, P = 0.040) were independent risk factors for TSS. Moreover, the multiindex receiver operating characteristic curve demonstrated that the area under the curve for predicted probability was 0.799 (P < 0.001). Routine thoracic magnetic resonance imaging assessment is strongly recommended in CSS patients with OPLLc, HLFc, and enlarged TIA to screen for neglected but vital thoracic disease. [ABSTRACT FROM AUTHOR]