Cervical alignment and clinical outcome of anterior decompression with fusion vs. posterior decompression with fixation in kyphotic cervical spondylotic myelopathy

Abstract

Background contextCervical kyphosis is a common but potentially debilitating and challenging condition. There is controversy on the optimal surgical strategy for the treatment of kyphotic cervical spondylotic myelopathy (KCSM) using either anterior approach or posterior approach.IntroductionThe purpose of this study was to investigate the surgical efficacy of anterior decompression with fusion (ADF) vs. posterior decompression with fixation (PDF) for the treatment of KCSM, and to further analyze the changes of cervical spinal alignment parameters and axial symptoms (AS) severity after kyphotic correction.Materials and methodsWe retrospectively reviewed 117 patients with KCSM who had undergone ADF (58 patients) and PDF (59 patients) between January 2016 and December 2020. Cervical spinal alignment parameters, including curvature index (CI) and C2-7 Cobb angle, were measured on the PreOP and PostOP lateral radiographs. Recovery rate was calculated based on the Japanese Orthopedic Association (JOA) score. AS severity was quantified by Neck Disability Index (NDI). A P-value less than 0.05 was considered to be significant.ResultsThe patient mean age, gender, presenting symptoms and follow-up time were similar between the two groups (P > 0.05). However, there were statistically significant differences (P < 0.001) between the two groups regarding the operation levels, operating time and intraoperative blood loss. Analysis of PostOP follow-up data showed significant differences (P < 0.001) in CI, correction of CI, C2-7 Cobb angle, and NDI between the two groups, whereas no significant differences in JOA score (P = 0.16) and recovery rate (P = 0.14). There were significant differences (P < 0.001) in CI, C2-7 Cobb angle, JOA score, and NDI between PreOP and PostOP follow-up in each group. Correction of CI showed positive correlation with recovery of NDI in Group ADF (r = 0.51, P < 0.001), and in Group PDF (r = 0.45, P < 0.001).ConclusionSatisfied neurological improvement was obtained by ADF and PDF for patients with KCSM. Cervical kyphotic correction caused significant improvement of AS, and was more favorable with ADF than with PDF. Surgeons should pay full consideration of the merits and shortcomings of each approach when deciding on a surgical plan.

Current Concepts of Cervical Spine Alignment, Sagittal Deformity, and Cervical Spine Surgery

“…Fifteen studies that showed the relationship between cervical alignment and outcome following posterior fusion are listed in Table 3 [ 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 116 ]. We summarize the pre- and postoperative risk factors for each parameter and other etiologies in the cervical spine in Table 3 .…”

“…Satisfactory neurological improvement was obtained with all of the surgical types. However, ADF was more suitable than P-F in restricting postoperative kyphotic change and an increase in SVA, even if ADF was not suitable for more than three levels of spinal cord compression [ 101 ]. Another article revealed that the most important cervical sagittal parameters correlating with clinical outcomes were C7 slope, occipito-C2 angle, external auditory meatus tilt, and SVA and that ADF more efficiently restored cervical sagittal alignment [ 102 ].…”

“…We also summarize the relationship between postoperative cervical malalignment and HRQOL outcome measures based on the NDI, VAS, SF-36, and mJOA questionnaires in Table 3. [101][102][103][104][105][106][107] (Table 3) Several articles investigated the surgical efficacy of ADF vs. laminoplasty only vs. P-F as the treatment for CSM and further analyzed the changes in cervical spinal alignment parameters and HRQOL outcome. Satisfactory neurological improvement was obtained with all of the surgical types.…”

Cervical alignment and clinical outcome of anterior cervical discectomy and fusion vs. anterior cervical corpectomy and fusion in local kyphotic cervical spondylotic myelopathy

“…Cervical spondylotic myelopathy (CSM) is a chronic degenerative disorder, which often involve the spinal cord compression or ischemia, producing a gradual decrease in neurological function and patient's quality of life. On X-rays, patients with CSM often show cervical local kyphosis (CLK) due to the intervertebral height decrease and sagittal lordotic malalignment, as well as the discs and facet joints degeneration [ 1 ]. Major symptoms include neck fatigue, neck pain, myelopathy, radiculopathy, horizontal gaze problems, and swallowing and breathing abnormalities [ 2 ].…”