Purpose: To determine whether radiological, clinical, and demographic findings in patients with cervical spondylotic myelopathy (CSM) were independently associated with loss of cervical lordosis (LCL) after laminoplasty.
Methods: The prospective study included 41 consecutive patients who underwent laminoplasty for CSM. The difference in C2-7 Cobb angle between the postoperative and preoperative films was used to evaluate change in cervical alignment. Age, sex, body mass index (BMI), smoking history, preoperative C2-7 Cobb angle, T1 slope, C2-7 range of motion (C2-7 ROM), C2-7 sagittal vertical axis (C2-7 SVA), and cephalad vertebral level undergoing laminoplasty (CVLL) were assessed. Data were analyzed using Pearson and Spearman correlation test, and univariate and stepwise multivariate linear regression.
Results: T1 slope, C2-7 SVA, and CVLL significantly correlated with LCL (P < 0.001), whereas age, BMI, and preoperative C2-7 Cobb angle did not. In multiple linear regression analysis, higher T1 slope (B = 0.351, P = 0.037), greater C2-7 SVA (B = 0.393, P < 0.001), and starting laminoplasty at C4 level (B = - 7.038, P < 0.001) were significantly associated with higher postoperative LCL.
Conclusions: Cervical alignment was compromised after laminoplasty in patients with CSM, and the degree of LCL was associated with preoperative T1 slope, C2-7 SVA, and CVLL.
Keywords: Cervical spondylotic myelopathy; Kyphosis; Kyphotic alignment change; Laminoplasty; Lordosis; Sagittal alignment; Sagittal balance.