Comparison of Anterior Cervical Discectomy and Fusion with Cervical Laminectomy and Fusion in the Treatment of 4-Level Cervical Spondylotic Myelopathy

Comparison of Anterior Surgery Versus Posterior Surgery for the Treatment of Multilevel Cervical Spondylotic Myelopathy: A Meta-Analysis

STUDY DESIGN

A meta-analysis.

OBJECTIVE

To evaluate the impact of anterior versus posterior surgical approaches on outcomes in MCSM.

BACKGROUND

Multilevel cervical spondylotic myelopathy (MCSM) is the most common cause of spinal cord dysfunction, and the clinical effectiveness of anterior versus posterior surgical approaches remains elusive.

METHODS

A comprehensive search was conducted across electronic databases, including MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials, to evaluate the effects of anterior surgery versus posterior surgery on outcomes, such as Japanese Orthopedic Association (JOA) score, neck disability index (NDI) score, neck visual analog scale (VAS), blood loss, operation time, length of stay, cervical range of motion, cervical Cobb angle, and complications. The baseline characteristics of the included studies were assessed using the Newcastle-Ottawa Scale score to measure the risk of bias.

RESULTS

In this meta-analysis, 14 retrospective and 6 prospective cohort studies, involving 2712 patients, were included. The analysis indicated no significant difference between the 2 groups in preoperative JOA score, postoperative JOA score, JOA recovery rate, postoperative neck VAS score, operation time, preoperative range of motion (ROM), or SF-36 score (P=0.95, 0.15, 0.20, 0.31, 0.94, 0.33, and 0.43, respectively). However, the NDI score and blood loss were significantly lower in the anterior surgery group compared with the posterior surgery group (P<0.04, P=0.0003). The anterior surgery group was also associated with shorter length of stay (P<0.00001), while had higher rates of complications (P=0.04). C2-7 Cobb angle and postoperative ROM were significantly lower in the anterior surgery group than those in the posterior surgery group (P=0.0002 and 0.01, respectively).

CONCLUSION

This meta-analysis found no clear advantage of 1 surgical approach over the other for MCSM in terms of neurological function recovery, as measured by JOA scores. The anterior approach was associated with improved NDI scores, lower blood loss, shorter length of stay, and better recovery of cervical lordosis, accompanied by limited postoperative mobility. Careful consideration should be given to potential complications, including dysphagia with the anterior surgery, axial pain, and C5 palsy with the posterior surgery.

Risk factors for poor neurological recovery after anterior cervical discectomy and fusion: imaging characteristics

BACKGROUND

Poor neurological recovery in patients after anterior cervical discectomy and fusion has been frequently reported; however, no study has analyzed the preoperative imaging characteristics of patients to investigate the factors affecting surgical prognosis. The purpose of this study was to investigate the factors that affect the preoperative imaging characteristics of patients and their influence on poor neurologic recovery after anterior cervical discectomy and fusion.

METHODS

We retrospectively analyzed the clinical data of 89 patients who met the criteria for anterior cervical discectomy and fusion for the treatment of single-level cervical spondylotic myelopathy and evaluated the patients' neurological recovery based on the recovery rate of the Japanese Orthopaedic Association (JOA) scores at the time of the final follow-up visit. Patients were categorized into the "good" and "poor" groups based on the JOA recovery rates of ≥ 50% and < 50%, respectively. Clinical information (age, gender, body mass index, duration of symptoms, preoperative JOA score, and JOA score at the final follow-up) and imaging characteristics (cervical kyphosis, cervical instability, ossification of the posterior longitudinal ligament (OPLL), calcification of herniated intervertebral discs, increased signal intensity (ISI) of the spinal cord on T2-weighted imaging (T2WI), and degree of degeneration of the discs adjacent to the fused levels (cranial and caudal) were collected from the patients. Univariate and binary logistic regression analyses were performed to identify risk factors for poor neurologic recovery.

RESULTS

The mean age of the patients was 52.56 ± 11.18 years, and the mean follow-up was 26.89 ± 11.14 months. Twenty patients (22.5%) had poor neurological recovery. Univariate analysis showed that significant predictors of poor neurological recovery were age (p = 0.019), concomitant OPLL (p = 0.019), concomitant calcification of herniated intervertebral discs (p = 0.019), ISI of the spinal cord on T2WI (p <0.05), a high grade of degeneration of the discs of the cranial neighboring levels (p <0.05), and a high grade of discs of the caudal neighboring levels (p <0.05). Binary logistic regression analysis showed that ISI of the spinal cord on T2WI (p = 0.001 OR = 24.947) and high degree of degeneration of adjacent discs on the cranial side (p = 0.040 OR = 6.260) were independent risk factors for poor neurological prognosis.

CONCLUSION

ISI of the spinal cord on T2WI and high degree of cranial adjacent disc degeneration are independent risk factors for poor neurological recovery after anterior cervical discectomy and fusion. A comprehensive analysis of the patients' preoperative imaging characteristics can help in the development of surgical protocols and the management of patients' surgical expectations.

[Analysis of imaging characteristics and effectiveness of cervical spondylotic myelopathy with cervical kyphosis]

Objective

To investigate the imaging characteristics of cervical kyphosis and spinal cord compression in cervical spondylotic myelopathy (CSM) with cervical kyphosis and the influence on effectiveness.

Methods

The clinical data of 36 patients with single-segment CSM with cervical kyphosis who were admitted between January 2020 and December 2022 and met the selection criteria were retrospectively analyzed. The patients were divided into 3 groups according to the positional relationship between the kyphosis focal on cervical spine X-ray film and the spinal cord compression point on MRI: the same group (group A, 20 cases, both points were in the same position), the adjacent group (group B, 10 cases, both points were located adjacent to each other), and the separated group (group C, 6 cases, both points were located >1 vertebra away from each other). There was no significant difference between groups ( P>0.05) in baseline data such as gender, age, body mass index, lesion segment, disease duration, and preoperative C 2-7 angle, C 2-7 sagittal vertical axis (C 2-7 SVA), C 7 slope (C 7S), kyphotic Cobb angle, fusion segment height, and Japanese Orthopedic Association (JOA) score. The patients underwent single-segment anterior cervical discectomy with fusion (ACDF). The occurrence of postoperative complications was recorded; preoperatively and at last follow-up, the patients' neurological function was evaluated using the JOA score, and the sagittal parameters (C 2-7 angle, C 2-7 SVA, C 7S, kyphotic Cobb angle, and height of the fused segments) were measured on cervical spine X-ray films and MRI and the correction rate of the cervical kyphosis was calculated; the correlation between changes in cervical sagittal parameters before and after operation and the JOA score improvement rate was analyzed using Pearson correlation analysis.

Results

In 36 patients, only 1 case of dysphagia occurred in group A, and the dysphagia symptoms disappeared at 3 days after operation, and the remaining patients had no surgery-related complications during the hospitalization. All patients were followed up 12-42 months, with a mean of 20.1 months; the difference in follow-up time between the groups was not significant ( P>0.05). At last follow-up, all the imaging indicators and JOA scores of patients in the 3 groups were significantly improved when compared with preoperative ones ( P<0.05). The correction rate of cervical kyphosis in group A was significantly better than that in group C, and the improvement rate of JOA score was significantly better than that in groups B and C, all showing significant differences ( P<0.05), and there was no significant difference between the other groups ( P>0.05). The correlation analysis showed that the improvement rate of JOA score was negatively correlated with C 2-7 angle and kyphotic Cobb angle at last follow-up ( r=-0.424, P=0.010; r=-0.573, P<0.001), and positively correlated with the C 7S and correction rate of cervical kyphosis at last follow-up ( r=0.336, P=0.045; r=0.587, P<0.001), and no correlation with the remaining indicators ( P>0.05).

Conclusion

There are three main positional relationships between the cervical kyphosis focal and the spinal cord compression point on imaging, and they have different impacts on the effectiveness and sagittal parameters after ACDF, and those with the same position cervical kyphosis focal and spinal cord compression point have the best improvement in effectiveness and sagittal parameters.

Intraspinal Extradural Degenerative Cervical Cyst Treated by Anterior Cervical Discectomy and Fusion: A Surgical Alternative to the Posterior Approach, about One Case

Introduction

Intraspinal extradural arthrosynovial cysts, which belong to the spectrum of degenerative spinal diseases are mainly located at lumbar level and their location at cervical level joint is therefore unusual. The most common surgical approach for symptomatic arthrosynovial cervical cyst remains a direct resection of the cyst by a cervical hemilaminectomy with or without a posterior arthrodesis. However, another surgical approach may also be discussed when considering the cyst as a result of a local spinal instability or hypermobility.

Case Report

We report in this work the case of a patient with cervical radiculopathy due to intraspinal extradural compressive arthrosynovial cervical cyst which was treated by anterior discectomy and fusion without direct resection of the cyst. The post-operative radiological control performed at 3 months showed a complete regression of the cyst with a patient pain-free. To the best of our knowledge, this is the first case of intraspinal cervical degenerative cyst at C7-T1 level treated by anterior approach and fusion without direct cyst resection.

Conclusion

For the treatment of a joint spinal cervical cyst, the anterior approach is a relevant option that gives the advantages to respect the posterior cervical muscles and articular structures.

Risk Factors for Significant Intraoperative Blood Loss during Anterior Cervical Decompression and Fusion for Degenerative Cervical Diseases

OBJECTIVES

Anterior cervical decompression and fusion (ACF) has become a widely accepted surgical treatment for degenerative cervical diseases, but occasionally, significant intraoperative blood loss (SIBL), which is defined as IBL of 500 mL or more, will occur. We aimed to investigate the independent risk factors for SIBL during ACF for degenerative cervical diseases.

METHODS

We enrolled 1150 patients who underwent ACF for degenerative cervical diseases at our hospital between 2013 and 2019. The patients were divided into two groups: the SIBL group (n = 38) and the non-SIBL group (n = 1112). Demographic, surgical and radiographic data were recorded prospectively to investigate the independent risk factors for SIBL. For counting data, the chi-square test or Fisher's exact probability test was used. Student's t-test or the Mann-Whitney rank sum test was used for comparisons between groups of measurement data. Univariate analysis and multivariate logistic regression analysis were further used to analyze the significance of potential risk factors.

RESULTS

The incidence of SIBL during ACF was 3.3% (38/1150). A multivariate analysis revealed that female sex (odds ratio [OR], 6.285; 95% confidence interval [CI], 2.707-14.595; p < 0.001), corpectomy (OR, 3.872; 95% CI, 1.616-9.275; p = 0.002), duration of operation ≥150 min (OR, 8.899; 95% CI, 4.042-19.590; p < 0.001), C3 involvement (OR, 4.116; 95% CI, 1.808-9.369; p = 0.001) and ossification of posterior longitudinal ligament (OPLL) at the surgical level (OR, 6.007; 95% CI, 2.218-16.270; p < 0.001) were independent risk factors for SIBL. Patients with SIBL had more days of first-degree/intensive nursing (p = 0.003), longer length of stay (p = 0.003) and higher hospitalization costs (p = 0.023).

CONCLUSION

Female sex, corpectomy, duration of operation, C3 involvement and OPLL at the surgical level were independent risk factors for SIBL during ACF. SIBL in ACF was associated with more days of first-degree/intensive nursing, longer length of stay and higher hospitalization costs.

Comparing two surgical approaches for treating multilevel cervical spondylotic myelopathy: A meta-analysis

PURPOSE

This meta-analysis aims to evaluate the therapeutic efficacy of anterior versus posterior surgical approaches for multisegment cervical spondylotic myelopathy (MCSM).

METHODS

Eligible studies published between the period of January 2001 and April 2022 and comparing the anterior and posterior surgical approaches for treating cervical spondylotic myelopathy were retrieved from the PubMed, Web of Science, Embase, and Cochrane databases.

RESULTS

A total of 17 articles were selected based on the inclusion and exclusion criteria. This meta-analysis failed to show any significant difference in the duration of surgery, the hospitalization time, or the improvement in the Japanese Orthopedic Association score between the anterior and posterior approaches. The anterior approach, however, exhibited increased efficacy in the improvement of the neck disability index, reduction in the visual analog scale for cervical pain, and improvement in the cervical curvature compared with the posterior approach.

CONCLUSION

Bleeding was also less with the anterior surgical approach. The posterior approach provided a significantly higher range of motion of the cervical spine and showed fewer postoperative complications compared with the anterior approach. While both the surgical approaches have good clinical outcomes and show postoperative neurological function improvement, the meta-analysis shows that both anterior and posterior approaches have certain merits and shortcomings. A meta-analysis of a larger number of randomized controlled trials with longer follow-up can conclusively determine which of the surgical approaches is more beneficial in the treatment of MCSM.

Static mechanical analysis of the vertebral body after modified anterior cervical discectomy and fusion (partial vertebral osteotomy): a finite element model

BACKGROUND

Modified anterior cervical discectomy and fusion (Mod ACDF) can effectively address ossification of the posterior longitudinal ligament (OPLL), which is difficult to remove directly from the posterior edge of the vertebral body, with considerably lesser damage as compared to anterior cervical corpectomy and fusion (ACCF). We compared the static mechanics of different anterior approaches by using an ideal finite element model.

METHODS

A complete finite element model was established and classified into the following three surgical models according to different model cutting operations: ACDF, ACCF, and Mod ACDF. Three different bone volume situations (normal bone mineral density, osteopenia, and osteoporosis) were simulated. After fixing the lower surface of C5 or C6, a load was applied to the upper surface of C4, and the stress distribution and displacement of the upper surface of C5 or C6 were observed and the related values were recorded.

RESULTS

The average Von Mises Stress and displacement levels of Mod ACDF were between those of ACDF and ACCF; with the peak Von Mises Stress occurring on the posterior side of the vertebral body (Points 1-4). The change in Von Mises Stress of the vertebral body is not significant during bone loss. However, the degree of displacement of the vertebral body surface and risk of vertebral collapse are increased (100 N: 13.91 vs. 19.47 vs. 21.62 μm; 150 N: 19.60 vs. 29.30 vs. 31.64 μm; 200 N: 28.53 vs. 38.65 vs. 44.83 μm).

CONCLUSIONS

The static biomechanical effects caused by Mod ACDF are intermediate between ACDF and ACCF, and the risk of vertebral body collapse is lower than that by ACCF. Therefore, Mod ACDF may be an effective solution when targeting OPLL with poorly positioned posterior vertebral body edges.

Clinical efficacy of duloxetine in the treatment of axial symptoms after posterior cervical spine surgery: a retrospective study

PURPOSE

To evaluate the efficacy of duloxetine in the treatment of patients with axial symptoms after posterior cervical spine surgery.

METHODS

Patients with axial symptoms after posterior cervical spine surgery treated by duloxetine or non-drug therapy from 2018 to 2021 were reviewed. Duloxetine was administered gradually, with oral administration of 30 mg in the first week and oral administration of 60 mg from the second week. Visual analogue scale (VAS), 36-Item Short-Form Health Survey questionnaire (SF-36) and EuroQol-5 Dimensions (EQ-5D) questionnaire were used to evaluate the severity of AS at baseline and 1 week, 2 weeks, 1 month, 3 months and 6 months after medication. The occurrence of adverse reactions was recorded.

RESULTS

A total of 63 eligible patients who received duloxetine therapy (n = 35) or non-drug therapy (n = 28) were included. All patients were followed up for 6 months. Significant improvements were found in VAS score compared with baseline in both groups (1.87 ± 0.81 vs 6.61 ± 1.16, 3.18 ± 0.67 vs 6.31 ± 1.40; P < 0.05 for all). Meanwhile, the VAS score of the duloxetine group was significantly better than that of the non-drug therapy group at 1 week, 2 weeks, 1 month, 3 months and 6 months (P < 0.05). Besides, according to 36-Item Short-Form Health Survey questionnaire (SF-36), the PCS score and MCS score are significantly higher than before the treatment in duloxetine group (PCS 62.82 ± 6.04 vs 44.36 ± 7.25, MCS 65.50 ± 4.53 vs 55.55 ± 6.06; P < 0.05 for all). And when we compared variables between the two groups, the PCS score of the duloxetine group was significantly better than that of the non-drug therapy group (P < 0.05), but there was no significant difference in MCS score between the two groups (P > 0.05). What's more, EQ-5D score had significant improvements in the duloxetine group compared with the non-drug therapy group at 1 week, 2 weeks, 1 month, 3 months and 6 months (P < 0.05).

CONCLUSION

Oral duloxetine has a better short-term outcome than conventional non-drug therapy in patients with axial symptoms following posterior decompression surgery in the cervical spine.

Anterior and Posterior Approaches for 4-Level Degenerative Cervical Myelopathy: Low-Profile Cage Versus Cervical Pedicle Screws Fixation

(1) Background: The choice of surgical access for 4-level degenerative cervical myelopathy (DCM) remains controversial, and the clinical and radiological outcomes of anterior surgery using a low-profile cage (Low-P) versus posterior surgery using cervical pedicle screw fixation (CPS) have not been compared. (2) Methods: This is a retrospective controlled study conducted between January 2019 and June 2021 of 72 patients with 4-level DCM who underwent ACDF using a low-profile cage (n = 39) or laminectomy and instrument fusion using CPS (n = 33). The minimum follow-up time was 12 months. The outcomes were C2−7Cobb angle, C2−7sagittal vertical axis (SVA) fusion rate, the Japanese Orthopedic Association (JOA) score, pain visual analog scale (VAS), neck disability index (NDI), and complications. (3) Results: Both anterior and posterior procedures significantly improved the patients’ quality-of-life parameters. Anterior cervical convexity and SVA significantly increased in both groups, but the SVA was greater in the posterior group than in the anterior group (p < 0.001). The C2−7 Cobb angle significantly improved in both groups postoperatively, and at the final follow-up, there was a slight but nonsignificant reduction in cervical lordosis in both groups (p = 0.567). There was a longer operative time, less intraoperative blood loss, and reduced mean hospital stay in the anterior group compared to the posterior group, with two cases of postoperative hematoma requiring a second operation, two cases of axial pain (AP), five cases of dysphagia, two cases of c5 palsy in the anterior group, and four cases of axial pain, and three cases of c5 palsy in the posterior group. According to Bridwell fusion grade, anterior fusion reached grade I in 28 cases (71.8%) and grade II in 10 cases (25.6%) in the anterior group, and posterior fusion reached grade I in 25 cases (75.8%) and grade II in 8 cases (24.2%) in the posterior group. (4) Conclusions: There was no difference between the anterior and posterior surgical approaches for MDCM in terms of improvement in neurological function. Posterior surgery using CPS achieved similar recovery of cervical anterior convexity as anterior surgery with a shorter operative time but was more invasive and had a greater increase in SVA. The use of Low-P in anterior surgery reduced the incidence of dysphagia and cage subsidence and was less invasive, but with a longer operative time.