Impact of surgeries on normal match of T1 slope and cervical lordosis in cervical spondylotic myelopathy.

Abstract

Objective: The objective of this study was to explore the normal matching changes between T1 slope (T1S) and cervical lordosis (CL) in patients with multilevel cervical spondylotic myelopathy (CSM) after anterior and posterior reconstruction surgeries.

Materials and methods: One hundred thirty-four patients diagnosed with multilevel CSM and a normal matching of T1S-CL were enrolled from the medical records spanning 2015-2020. The anterior group comprised 69 patients, and the posterior group included 65 patients. This study retrospectively analyzed perioperative parameters, including clinical parameters of the Japanese Orthopedic Association (JOA) score, Visual Analog Scale (VAS), neck disability index (NDI), and radiologic parameters T1S, CL, C2-7 sagittal vertical axis (SVA), and T1S-CL.

Results: Prior to surgery, there were no significant differences in factors between two groups (P > 0.05). Postoperatively, while the JOA scores were similar between groups (P > 0.05), the anterior group showed significantly lower in NDI, VAS, perioperative parameters, and incidences of complications (P < 0.001). Significant changes were observed in each group for T1S, CL, C2-7 SVA and T1S-CL (P < 0.001). Preoperatively, in the anterior group, significant correlations were identified between T1S-CL and T1S, CL, and C2-7 SVA (P < 0.05). In the posterior group, significant correlations were observed between T1S-CL and T1S, CL, and C2-7 SVA (P < 0.05). Following surgery, in the anterior group, the correlations persisted between T1S-CL and T1S, CL, and C2-7 SVA (P < 0.05). In the posterior group, the correlations between T1S-CL and T1S, and CL were not significant (P > 0.05). The comparative analysis of parameter changes between anterior and posterior groups revealed no significant difference in the changes of T1S and C2-7 SVA (P > 0.05), whereas significant differences were observed in the changes of C2-7 lordosis and T1S-CL (P < 0.001).

Conclusions: Anterior reconstruction surgeries can improve or optimize the normal matching of T1S-CL, while a mismatching of T1S and CL is more likely to occur after posterior surgery, potentially leading to cervical sagittal malalignment and imbalance in patients with multilevel CSM.