Reoperation Rates after Laminoplasty for Cervical Disorders: A 26-Year Period Survival Function Method Analysis

Reoperation rate and risk factors of reoperation for ossification of the posterior longitudinal ligament (OPLL): a systematic review and meta-analysis

Revision surgery for OPLL is undesirable for both patients and physicians. However, the risk factors for reoperation are not clear. Thus, we sought to review the existing literature and determine the factors associated with higher reoperation rates in patients with OPLL. A search was performed using Pubmed, Embase, Web of Sciences, and Ovid to include studies regarding the risk factors of reoperation for OPLL. RoBANS (Risk of Bias Assessment tool for Nonrandomized Studies) was used for risk of bias analysis. Heterogeneity of studies and publication bias was assessed, and sensitivity analysis was performed. Statistical analysis was performed with a p-value < 0.05 using SPSS software (version 23). Twenty studies with 129 reoperated and 2,793 non-reoperated patients were included. The pooled reoperation rate was 5% (95% CI: 4% to 7). The most common cause of reoperation was residual OPLL or OPLL progression (n = 51, 39.53%). An increased risk of additional surgery was found with pre-operative cervical or thoracic angle (Standardized mean difference = -0.44; 95% CI: -0.69 to -0.19; p = 0.0061), post-operative CSF leak (Odds ratio, OR = 4.97; 95% CI: 2.48 to 9.96; p = 0.0005), and graft and/or hardware failure (OR = 192.09; 95% CI: 6.68 to 5521.69; p = 0.0101). Apart from the factors identified in our study, the association of other variables with the risk of second surgery could not be ruled out, owing to the complexity of the relationship and significant bias in the current literature.

Long-Term Survivorship of Cervical Spine Procedures; A Survivorship Meta-Analysis and Meta-Regression

STUDY DESIGN

Systematic Review.

OBJECTIVES

To conduct a meta-analysis on the survivorship of commonly performed cervical spine procedures to develop survival function curves for (i) second surgery at any cervical level, and (ii) adjacent level surgery.

METHODS

A systematic review of was conducted following PRISMA guidelines. Articles with cohorts of greater than 20 patients followed for a minimum of 36 months and with available survival data were included. Procedures included were anterior cervical discectomy and fusion (ACDF), cervical disc arthroplasty (ADR), laminoplasty (LAMP), and posterior laminectomy and fusion (PDIF). Reconstructed individual patient data were pooled across studies using parametric Bayesian survival meta-regression.

RESULTS

Of 1829 initial titles, 16 citations were included for analysis. 73 811 patients were included in the second surgery analysis and 2858 patients in the adjacent level surgery analysis. We fit a Log normal accelerated failure time model to the second surgery data and a Gompertz proportional hazards model to the adjacent level surgery data. Relative to ACDF, the risk of second surgery was higher with ADR and PDIF with acceleration factors 1.73 (95% CrI: 1.04, 2.80) and 1.35 (95% CrI: 1.25, 1.46) respectively. Relative to ACDF, the risk of second surgery was lower with LAMP with deceleration factor .06 (95% CrI: .05, .07). ADR decreased the risk of adjacent level surgery with hazard ratio .43 (95% CrI: .33, .55).

CONCLUSIONS

In cases of clinical equipoise between fusion procedures, our analysis suggests superior survivorship with anterior procedures. For all procedures, laminoplasty demonstrated superior survivorship.

Treatment of cervical myelopathy by posterior approach: Laminoplasty vs. laminectomy with posterior fixation, are there differences from a clinical and radiological point of view?

INTRODUCTION

Cervical degenerative myelopathy is a variable and progressive degenerative disease caused by chronic compression of the spinal cord. Surgical approaches for the cervical spine can be performed anteriorly and/or posteriorly. Regarding the posterior approach, there are 2 fundamental techniques: laminoplasty and laminectomy with posterior fixation (LPF). There is still controversy concerning the technique in terms of outcome and complications. The aim of the present work is to analyze from the clinical and radiological point of view these 2 techniques: laminoplasty and LPF.

MATERIALS AND METHODS

A historical cohort of 39 patients was reviewed (12 LFP and 27 laminoplasty) including patients operated in a 10 years period at the Hospital Universitario La Paz with a follow-up of 12 months after surgery was carried out. The clinical results were analyzed and compared using the Nurick scale and the modified Japanese Orthopaedic Association Scale (mJOA) and the radiological results using the Cobb angle, Sagittal Vertical Axis, T1 Slope and alignment (measured by Cobb-T1 Sloppe).

RESULTS

Significant differences were observed in the postoperative improvement of the Nurick scale (p = 0.008) and mJOA (p = 0.018) in the laminoplasty group. In LFP there is a tendency to a greater improvement, but statistical significance is not reached due to the low sample size of this group. No statistically significant differences were observed in the radiological variables. Regarding the total number of complications, a higher number was observed in the laminoplasty group (7 cases) versus LFP (one case), but no statistically significant differences were observed.

CONCLUSIONS

Laminoplasty and LFP are both safe and effective procedures in the treatment of cervical degenerative myelopathy. The findings of our study demonstrate statistically significant clinical improvement based on the Nurick and mJOA scales with laminoplasty. No significant differences in terms of complications or radiological variables were observed between the 2 techniques.

Open-door laminoplasty with stand-alone autologous bone spacers: evaluation of enlarged laminar arch with CT-multiplanar reconstruction

OBJECTIVE

The authors aimed to determine the efficacy of open-door laminoplasty with stand-alone autologous bone spacer for preserving enlarged lamina in patients with cervical myelopathy.

METHODS

Patients who underwent open-door laminoplasty for cervical myelopathy with stand-alone autologous bone spacer and underwent CT 1 week and 1 year after surgery were included in this study. There were 20 men and 13 women, with an average (range) age of 65.0 (37-86) years. Seventeen patients were younger than 70 years, and 16 patients were older than 70 years. Autogenous bone spacers made from spinous processes were used in all patients. Slits were made on both sides of the spacers. The lamina was raised with a curette, and a spacer was inserted without any sutures. Before surgery and 1 week and 1 year after surgery, the anteroposterior diameter (APD) of the spinal canal was measured using midsagittal-plane CT-multiplanar reconstruction. The bone union rate of the hinge side and autogenous bone spacer of each lamina was determined using CT images obtained 1 year after surgery. Results 1 year after surgery were evaluated using Japanese Orthopaedic Association (JOA) score.

RESULTS

The mean ± SD APD increase rate was 56.3% ± 21.3% 1 week after surgery and 51.7% ± 20.6% 1 year later. The average APD decrease rate was 2.9% ± 3.8%. The bone union rate on the hinge side was 100%, and that of autologous bone spacer was 93.8% 1 year after surgery. The mean APD decrease rate was 3.3% in patients younger than 70 years and 2.3% in those older than 70 years. There was no significant difference between the two groups (p > 0.05, nonpaired t-test). The JOA score averaged 10.1 before surgery and 13.3 a year after surgery (total score 17). The average improvement rate was 46.3% ± 26.4%.

CONCLUSIONS

The authors devised and implemented a technique for inserting an autologous bone spacer between the opened lamina and lateral mass without sutures. The enlarged spinal canal was maintained 1 year after surgery. This simple method does not require any instrumentation or additional cost to stabilize the opened lamina.