Comparison Of Changes Of Sagittal Position Parameters And Curative Effect In Anterior And Posterior Cervical Spine Surgery For Multilevel Cervical Spondylotic Myelopathy

Objective: Anterior segmental combined decompression and bone graft fusion(ACHDF)and posterior single-door laminoplasty(LAMP)have been reported for the treatment of multisegmental cervical spondylotic myelopathy(MCSM).Although widely used clinically,there are still some differences between ACHDF and LAMP surgery.This study compared ACHDF and LAMP in the treatment of multi-level cervical spondylotic myelopathy with sagittal cervical parameter changes and efficacy.Methods: Retrospective analysis was performed on 78 patients with multi-segment cervical spondylotic myelopathy undergoing surgical treatment from January 2013 to July 2017 in the Department of Spinal Surgery.Bone fusion was performed in 43 patients(ACHDF group)and posterior single-door open canal augmentation angioplasty in 35 patients(LAMP group).Angles were measured on the lateral X-ray of the cervical spine.Measured and analyzed parameters before and during follow-up,including thoracic access Parameters: T1 tilt angle(T1S),thoracic inlet angle(TIA),cervical dip(NT);cervical parameters: cervical lordosis angle(C2-7Cobb angle),C2-C7 sagittal vertical axis distance(C2-7SVA).Use the score of the Japanese Orthopaedic Association(JOA),axial symptom assessment of clinical efficacy.Results: There was no significant difference in preoperative C2-7COBB,C2-7SVA,T1 S,TIA,NT between the two groups.There was no significant difference between the two groups in follow-up T1 S,TIA,and NT.The C2-7Cobb angle was(16.92±7.08)° in the ACHDF group,(12.17±8.77)° in the LAMP group(P = 0.028),(16.58±11.33)mm in the ACHDF group and(23.60±16.21)mm in the LAMP group(P = 0.034).Follow-up C2-7COBB and C2-7SVA were significantly different between the ACHDF group and the LAMP group(all P<0.05).There was no significant difference in sagittal parameters between preoperative and follow-up in the ACHDF group,but there was a significant difference between preoperative and follow-up C2-7COBB and C2-7SVA in the LAMP group.The improvement rate of JOA in the ACHDF group was 66.73%,and the JOA improvement rate in the LAMP group was 52.87%.The difference between the two groups was statistically significant(P<0.05).JOA improvement rate was not significantly related to sacrotyping parameter values ?Cobb,?NT,?SVA,?T1S,?TIA(P>0.05).Postoperative changes of parameters of the sagittal and axial symptom a correlation between postoperative reduction,C2-7SVA C2-7Cobb angle increases,increased incidence of axial symptom,the difference was statistically significant(P<0.05).Conclusion: Anterior segmental segmental decompression,bone grafting,and fusion fixation is superior to postoperative single open-door laminoplasty in improving postoperative sagittal balance of cervical spine.ACHDF is more effective than LAMP in improving cervical spinal cord function in multi-segmental cervical spondylosis More advantages.Regardless of the anterior or posterior axis,there was no significant correlation between postoperative cervical sagittal parameter changes and JOA scores.The occurrence of axial symptoms after anterior surgery was superior to posterior cervical approach,which may be related to the reduction of C2-7 Cobb angle of cervical sagittal plane and the increase of C2-7SVA.