The Association of the Changes in Pain Severity and Cervical Cobb Angle before Versus After Anterior Cervical Discectomy With Fusion Surgery

Abstract

Background and Aim: Axial neck pain due to degenerative cervical myelopathy can be improved after repairing anterior cervical discectomy with fusion (ACDF) surgery. However, whether changes in postoperative pain can be associated with improvement in the Cobb angle following surgery is still controversial. This study aims to assess the trends of the changes in pain severity and also Cobb angle and then test the relationship between the changes in two parameters. Methods and Materials/Patients: This longitudinal study was performed on 60 consecutive patients who were scheduled to undergo ACDF surgery due to neck disc or degenerative cervical myelopathy (DCM) and had axial neck pain before the operation. Before operation as well as 2 weeks, 2 months and 6 months after surgery, the pain score and value of Cobb angle were measured. Results: Before surgery, the patients suffered from significant axial neck pain with a mean pain score of 7.47±2.02, but after surgery, patients experienced a downward trend of changes in pain score as the mean pain score of 0.92±1.46 at two weeks, 1.31±1.63 at two months and 1.32±1.64 at six months after operation. The repeated measure analysis of variance (ANOVA) test showed a significant reduction in pain scores within follow-up time (P<0.001). A significant improvement was also revealed in the Cobb angle after the operation and the mean value of this angle was significantly lower at two weeks, two months, and six months after surgery than before surgery. Using the multivariate linear regression modeling with the presence of baseline parameters, the relationship between pain score and Cobb angle remained insignificant (P=0.387). Conclusion: Following ACDF surgery, the improvement in axial neck pain and Cobb angle is predictable, but the relationship between these two indicators will not necessarily be significant.