Predictive Effect of Cervical Sagittal Parameters on Conservative Treatment of Single-Segment Cervical Spondylotic Radiculopathy

Abstract

To explore whether the cervical sagittal parameters affect the conservative treatment of single-segment cervical spondylotic radiculopathy and whether the conservative treatment of single-segment cervical spondylotic radiculopathy can be predicted by cervical sagittal parameters. Cervical spondylotic radiculopathy is currently treated with a stepwise approach, and conservative treatment is recommended. However, there is insufficient evidence to support the efficacy of conservative treatment. Between January 2013 and January 2018, 121 patients with single-segment cervical spondylotic radiculopathy were enrolled in this study. The inclusion criteria included complete cervical lateral radiographs. The following radiographic parameters were measured: C0-2 Cobb angle; C2-7 Cobb angle (CL), C7 slope (C7S), neck tilt (NT), thoracic inlet angle (TIA), T1 slope (T1S), C2-7 sagittal vertical axis (SVA), cervical tilt, cranial tilt, and cervical curvature index (CCI). Cervical spine function and quality of life were assessed using a visual analog scale (VAS) and the Neck Disability Index (NDI). According to the therapeutic effect, the patients were divided into group A (effective conservative treatment group) and group B (ineffective conservative treatment group). Effective conservative treatment was defined as conservative treatment for 3 months (1 nonsteroidal analgesic and 1 neurotrophic drug, supplemented by cervical traction and a neck support brace) resulting in a 60% reduction in NDI score. The Pearson correlation coefficient was used to calculate the correlation between each sagittal parameter and functional score. Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were used to determine independent risk factors and critical values. In the effective conservative treatment group (group A), the pretreatment NDI score was significantly positively correlated with the pretreatment VAS score and negatively correlated with CL, C7S, TIA, T1S, cervical tilt, and CCI. In the ineffective conservative treatment group (group B), the pretreatment NDI score was significantly positively correlated with the pretreatment VAS score and NT, and negatively correlated with age, CL, C7S, T1S, cervical tilt, and CCI. Based on logistic regression analysis and ROC curve analysis, we found that a larger C2-7 Cobb angle before treatment was the sole independent risk factor for conservative treatment (P < 0.001). Patients with a C2-7 Cobb angle >7.7° had a greater likelihood of receiving effective conservative treatment. In patients with single-segment cervical spondylotic radiculopathy, a larger C2-7 Cobb angle before treatment was the sole independent risk factor for effective conservative treatment (P < 0.001). Conservative treatment was more likely to be effective when the C2-7 Cobb angle is >7.7°.