Comparison Of Postoperative Sagittal Parameters And Clinical Efficacy Of Different Anterior Cervical Approaches In The Treatment Of Adjacent Of Two-segmental Cervical Spondylotic Myelopathy

Objective:To compare the clinical effect difference of two kinds of anterior cervical surgery in the treatment of adjacent two-segmental cervical spondylotic myelopathy and the influence on cervical sagittal balance parameters.To discuss the clinical significance of cervical sagittal balance parameters in anterior surgery.Methods:A retrospective analysis was conducted on 65 patients with adjacent two-segmental cervical spondylotic myelopathy who received anterior cervical surgery in our department from January 2015 to June 2019.Among them,37 cases were in the anterior cervical discectomy and fusion（ACDF）group,and 28 cases were in the anterior cervical corpectomy and fusion（ACCF）group.General data and perioperative parameters（operative time,intraoperative blood loss,hospital time）were compared between the two groups.Meanwhile,the cervical sagittal balance parameters:C2-7Cobb angle,segmental angle,C2-7SVA,T1 slope,clinical efficacy evaluation indexes:JOA and NDI scores were compared between and within the two groups before and after surgery.Pearson correlation analysis was used to analyze the correlation between cervical dysplasia balance parameters at each time point and clinical prognosis.Results:All the 65 patients were followed up for more than 1 year,and the mean follow-up time was（14.97±2.37）months.Perioperative parameters:ACCF group hospitalization time,intraoperative blood loss,operating time were significantly greater than the ACDF group,the differences were statistically significant（P<0.05）.Clinical efficacy evaluation indexes:preoperative JOA score and NDI score of ACDF group were（8.92±1.50）points and（32.57±4.29）points,respectively,and improved to（12.62±2.37）points and（14.30±2.60）points at the last follow-up,with statistical significance compared with preoperative（P<0.05）.The JOA score and NDI score of ACCF group were（8.46±1.29）and（33.89±4.81）points respectively before surgery,and improved to（12.96±2.08）and（14.36±2.42）points at the last follow-up,with statistical significance compared with preoperative（P<0.05）.Before surgery and at the last follow-up,the JOA and NDI scores were not statistically significant between the two groups（P>0.05）.Cervical sagittal balance parameters:In the ACDF group,the C2-7Cobb angle,SA,C2₇SVA and T1S were（17.83±1.87）°,（6.24±0.97）°,（20.48±1.73）mm and（35.87±3.13）° before surgery,respectively,and improved to（30.38±2.11）°,（13.66±1.19）°,（9.08±2.80）mm and（24.99±2.73）° at the last follow-up,with statistically significant differences compared with the preoperative values（P<0.05）.In the ACCF group,the C2-7Cobb angle,SA,C2-7SVA and T1S were（17.43±2.39）°,（6.15 ± 0.90）°,（21.10±2.12）mm and（35.76±3.34）°before operation,respectively,and improved to（26.10±2.01）°,（10.69±1.12）°,（12.76±1.70）mm and（28.11±3.53）° at the last follow-up,with statistical significance compared with preoperation（P<0.05）.Three months after surgery and at the last follow-up,there was a statistical difference in the parameters of the cervical spine sagittal plane between the two groups（P<0.05）.Pearson correlation analysis results indicate that C2-7SVA was positively correlated with T1S（r=0.246,P<0.05）,and negatively correlated with C2-7Cobb angle（r=-0.251,P<0.05）.C2-7Cobb was actively related to JOA score（r=0.312,P<0.05）and passively related to NDI score（r=-0.272,P<0.05）.C2-7SVA was negatively correlated with JOA score（r=-0.363,P<0.05）.Conclusion:1.In the anterior surgical treatment of adjacent two-segmental cervical Spondylotic myelopathy,the two surgical methods have the same effect,can obtain better clinical results,and can effectively improve the sagittal balance parameters of the cervical spine.2.There is a close correlation between the sagittal balance parameters of each cervical vertebra,and it is also closely related to the clinical curative effect.3.Compared with ACCF,ACDF has shorter hospitalization time,less intraoperative blood loss,shorter operation time,and more significant improvement of cervical sagittal balance.Therefore,when most of the two surgical methods can be selected,ACDF can be used as the first choice for the treatment of adjacent two-segmental cervical Spondylotic myelopathy.