Anterior or posterior approach in the surgical treatment of cervical radiculopathy; neurosurgeons’ preference in the Netherlands

Posterior Cervical Foraminotomy Compared with Anterior Cervical Discectomy with Fusion for Cervical Radiculopathy: Two-Year Results of the FACET Randomized Noninferiority Study

BACKGROUND

Posterior cervical foraminotomy (posterior surgery) is a valid alternative to anterior discectomy with fusion (anterior surgery) as a surgical treatment of cervical radiculopathy, but the quality of evidence has been limited. The purpose of this study was to compare the clinical outcome of these treatments after 2 years of follow-up. We hypothesized that posterior surgery would be noninferior to anterior surgery.

METHODS

This multicenter, randomized, noninferiority trial assessed patients with single-level cervical radiculopathy in 9 Dutch hospitals with a follow-up duration of 2 years. The primary outcomes measured reduction of cervical radicular pain and were the success ratio based on the Odom criteria, and arm pain and decrease in arm pain, evaluated with the visual analog scale, with a 10% noninferiority margin, which represents the maximum acceptable difference between the new treatment (posterior surgery) and the standard treatment (anterior surgery), beyond which the new treatment would be considered clinically unacceptable. The secondary outcomes were neck pain, Neck Disability Index, Work Ability Index, quality of life, complications (including reoperations), and treatment satisfaction. Generalized linear mixed effects modeling was used for analyses. The study was registered at the Overview of Medical Research in the Netherlands (OMON), formerly the Netherlands Trial Register (NTR5536).

RESULTS

From January 2016 to May 2020, 265 patients were randomized (132 to the posterior surgery group and 133 to the anterior surgery group). Among these, 25 did not have the allocated intervention; 11 of these 25 patients had symptom improvement, and the rest of the patients did not have the intervention due to various reasons. At the 2-year follow-up, of 243 patients, primary outcome data were available for 236 patients (97%). Predicted proportions of a successful outcome were 0.81 after posterior surgery and 0.74 after anterior surgery (difference in rate, -0.06 [1-sided 95% confidence interval (CI), -0.02]), indicating the noninferiority of posterior surgery. The between-group difference in arm pain was -2.7 (1-sided 95% CI, 7.4) and the between-group difference in the decrease in arm pain was 1.5 (1-sided 95% CI, 8.2), both confirming the noninferiority of posterior surgery. The secondary outcomes demonstrated small between-group differences. Serious surgery-related adverse events occurred in 9 patients (8%) who underwent posterior surgery, including 9 reoperations, and 11 patients (9%) who underwent anterior surgery, including 7 reoperations (difference in reoperation rate, -0.02 [2-sided 95% CI, -0.09 to 0.05]).

CONCLUSIONS

This trial demonstrated that, after a 2-year follow-up, posterior surgery was noninferior to anterior surgery with regard to the success rate and arm pain reduction in patients with cervical radiculopathy.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Short-Term Neck Pain After Posterior Foraminotomy Compared with Anterior Discectomy with Fusion for Cervical Foraminal Radiculopathy: A Secondary Analysis of the FACET Randomized Controlled Trial

BACKGROUND

Short-term neck pain after posterior cervical foraminotomy (posterior surgery) compared with anterior cervical discectomy with fusion (anterior surgery) treating cervical radiculopathy has only been assessed once, retrospectively, to our knowledge. The aim of this study was to prospectively evaluate the course of neck pain for 6 weeks after both treatments.

METHODS

This is a secondary analysis of the multicenter Foraminotomy ACDF Cost-Effectiveness Trial (FACET), conducted from January 2016 to May 2020. Of 389 patients who had single-level, 1-sided cervical radiculopathy and were screened for eligibility, 265 were randomly assigned to undergo posterior surgery (n = 132) or anterior surgery (n = 133). The primary outcome of the present analysis was neck pain, assessed weekly for 6 weeks using the visual analog scale (VAS), on a scale of 0 to 100. The secondary outcomes were arm pain, neck disability, work ability, quality of life, treatment satisfaction, motor and sensory changes, and hospital length of stay. Data were analyzed with mixed model analysis in intention-to-treat samples using 2-sided 95% confidence intervals (CIs).

RESULTS

In the first postoperative week, the mean VAS for neck pain was 56.2 mm (95% CI, 51.7 to 60.8 mm) after posterior surgery and 46.7 mm (95% CI, 42.2 to 51.2 mm) after anterior surgery. The mean between-group difference was 9.5 mm (95% CI, 3.3 to 15.7 mm), which gradually decreased to 2.3 mm (95% CI, -3.6 to 8.1 mm) at postoperative week 6. As of postoperative week 5, there was no significant difference between groups. Responder analyses confirmed this result. Secondary outcomes showed small differences between groups.

CONCLUSIONS

Insight into the course of neck pain during the first 6 weeks after posterior compared with anterior surgery is provided. Despite initially more neck pain after posterior surgery, patients swiftly improved and, as of postoperative week 5, results similar to those after anterior surgery were observed. Our findings should enable improved patient counseling and enhanced shared decision-making between physicians and patients with cervical radiculopathy, where more neck pain in the first postoperative weeks should be balanced against the benefits of posterior surgery.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Noninferiority of Posterior Cervical Foraminotomy vs Anterior Cervical Discectomy With Fusion for Procedural Success and Reduction in Arm Pain Among Patients With Cervical Radiculopathy at 1 Year: The FACET Randomized Clinical Trial

Importance

The choice between posterior cervical foraminotomy (posterior surgery) and anterior cervical discectomy with fusion (anterior surgery) for cervical foraminal radiculopathy remains controversial.

Objective

To investigate the noninferiority of posterior vs anterior surgery in patients with cervical foraminal radiculopathy with regard to clinical outcomes after 1 year.

Design, Setting, and Participants

This multicenter investigator-blinded noninferiority randomized clinical trial was conducted from January 2016 to May 2020 with a total follow-up of 2 years. Patients were included from 9 hospitals in the Netherlands. Of 389 adult patients with 1-sided single-level cervical foraminal radiculopathy screened for eligibility, 124 declined to participate or did not meet eligibility criteria. Patients with pure axial neck pain without radicular pain were not eligible. Of 265 patients randomized (132 to posterior and 133 to anterior), 15 were lost to follow-up and 228 were included in the 1-year analysis (110 in posterior and 118 in anterior).

Interventions

Patients were randomly assigned 1:1 to posterior foraminotomy or anterior cervical discectomy with fusion.

Main Outcomes and Measures

Primary outcomes were proportion of success using Odom criteria and decrease in arm pain using a visual analogue scale from 0 to 100 with a noninferiority margin of 10% (assuming advantages with posterior surgery over anterior surgery that would justify a tolerable loss of efficacy of 10%). Secondary outcomes were neck pain, disability, quality of life, work status, treatment satisfaction, reoperations, and complications. Analyses were performed with 2-proportion z tests at 1-sided .05 significance levels with Bonferroni corrections.

Results

Among 265 included patients, the mean (SD) age was 51.2 (8.3) years; 133 patients (50%) were female and 132 (50%) were male. Patients were randomly assigned to posterior (132) or anterior (133) surgery. The proportion of success was 0.88 (86 of 98) in the posterior surgery group and 0.76 (81 of 106) in the anterior surgery group (difference, -0.11 percentage points; 1-sided 95% CI, -0.01) and the between-group difference in arm pain was -2.8 (1-sided 95% CI, -9.4) at 1-year follow-up, indicating noninferiority of posterior surgery. Decrease in arm pain had a between-group difference of 3.4 (1-sided 95% CI, 11.8), crossing the noninferiority margin with 1.8 points. All secondary outcomes had 2-sided 95% CIs clustered around 0 with small between-group differences.

Conclusions and Relevance

In this randomized clinical trial, posterior surgery was noninferior to anterior surgery for patients with cervical radiculopathy regarding success rate and arm pain at 1 year. Decrease in arm pain and secondary outcomes had small between-group differences. These results may be used to enhance shared decision-making.

Trial Registration

Netherlands Trial Register Identifier: NTR5536.

Porous interbody fusion cage design via topology optimization and biomechanical performance analysis

The porous interbody fusion cage could provide space and stable mechanical conditions for postoperative intervertebral bone ingrowth. It is considered to be an important implant in anterior cervical discectomy and internal fixation. In this study, two types of unit cells were designed using topology optimization method and introduced to the interbody fusion cage to improve the biomechanical performances of the cage. Topology optimization under two typically loading conditions was first conducted to obtain two unit cells (O-unit cell and D-unit cell) with the same volume fraction. Porous structures were developed by stacking the obtained unit cells in space, respectively. Then, porous interbody fusion cages were obtained by the Boolean intersection between the global structural layout and the porous structures. Finite element models of cervical spine were created that C5-C6 segment was fused by the designed porous cages. The range of motion (ROM) of the cervical spine, the maximum stress on the cage and the bone graft, and the stress and displacement distributions of the cage were analyzed. The results showed the ROMs of C5-C6 segment in D-unit cell and O-unit cell models were range from 0.14° to 0.25° under different loading conditions; the cage composed of the D-unit cells had a more uniform stress distribution, smaller displacement on cage, a more reasonable internal stress transfer mode (transmission along struts of the unit cell), and higher stress on the internal bone graft (0.617 MPa). In conclusion, the optimized porous cage is a promising candidate for fusion surgery, which would avoid the cage subsidence, and promote the fusion of adjacent endplates.