Patterns in Decompression and Fusion Procedures for Patients With Lumbar Stenosis After Major Clinical Trial Results, 2016 to 2019

Comparison of Patients Operated for Lumbar Spinal Stenosis With and Without Spondylolisthesis​​​​​: A Secondary Analysis of the NORDSTEN Trials

STUDY DESIGN

Observational cohort study (secondary analysis of two randomized trials).

OBJECTIVE

The aim of this study was to investigate whether function, disability, pain, and quality of life before surgery and patient-reported outcome as well as complication and reoperation rates up to 2 years after surgery differ between lumbar spinal stenosis patients with and without spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Lumbar spinal stenosis is a degenerative condition of the spine, which appears with or without degenerative spondylolisthesis often presenting similar signs and symptoms.

MATERIALS AND METHODS

This study is a secondary analysis of two randomized trials on patients with lumbar spinal stenosis with and without spondylolisthesis conducted at 16 public Norwegian hospitals. Disability, function, back pain, leg pain, quality of life, complication, and reoperation rates up to 2 years after surgery were compared between the two cohorts.

RESULTS

A total of 704 patients were included in this study, 267 patients with spondylolisthesis [median age: 67.0 yr (IQR: 61.0-72.0 yr); 68.7% female] and 437 patients without spondylolisthesis [median age: 68.0 yr (IQR: 62.0-73.0 yr); 52.9% female]. In the linear mixed-model analysis there were no significant differences in disability, function, back pain, leg pain, and quality of life scores between the two cohorts of patient with and without spondylolisthesis before surgery or at 2 years of follow-up. The complication rate was 22.9% in patients with spondylolisthesis and 12.1% in patients without spondylolisthesis ( P <0.001). There were no significant differences in reoperation rates.

CONCLUSIONS

In patients with lumbar spinal stenosis the symptom burden before surgery and the clinical outcome up to 2 years after surgery were similar independently of a concomitant spondylolisthesis.

LEVEL OF EVIDENCE

II.

Clinical assessment and management of lumbar spinal stenosis: clinical dilemmas and considerations for surgical referral

Lumbar spinal stenosis is the leading indication for spine surgery in older adults. Surgery is recommended in clinical guidelines if non-surgical treatments have been provided with insufficient benefit. The difficulty for clinicians is that the current number of randomised controlled trials is low, which creates uncertainty about which treatments to provide. For non-surgical clinicians this paucity of data leads to a clinical dilemma of whether to continue managing the patient or refer to a spine surgeon. This Viewpoint aims to provide an update on the assessment of lumbar spinal stenosis, treatment recommendations, indications for referral to a spine surgeon, and current clinical dilemmas facing non-surgical clinicians and spinal surgeons.

Challenges in Contemporary Spine Surgery: A Comprehensive Review of Surgical, Technological, and Patient-Specific Issues

Spine surgery has significantly progressed due to innovations in surgical techniques, technology, and a deeper understanding of spinal pathology. However, numerous challenges persist, complicating successful outcomes. Anatomical intricacies at transitional junctions demand precise surgical expertise to avoid complications. Technical challenges, such as underestimation of the density of fixed vertebrae, individual vertebral characteristics, and the angle of pedicle inclination, pose additional risks during surgery. Patient anatomical variability and prior surgeries add layers of difficulty, often necessitating thorough pre- and intraoperative planning. Technological challenges involve the integration of artificial intelligence (AI) and advanced visualization systems. AI offers predictive capabilities but is limited by the need for large, high-quality datasets and the "black box" nature of machine learning models, which complicates clinical decision making. Visualization technologies like augmented reality and robotic surgery enhance precision but come with operational and cost-related hurdles. Patient-specific challenges include managing postoperative complications such as adjacent segment disease, hardware failure, and neurological deficits. Effective patient outcome measurement is critical, yet existing metrics often fail to capture the full scope of patient experiences. Proper patient selection for procedures is essential to minimize risks and improve outcomes, but criteria can be inconsistent and complex. There is the need for continued technological innovation, improved patient-specific outcome measures, and enhanced surgical education through simulation-based training. Integrating AI in preoperative planning and developing comprehensive databases for spinal pathologies can aid in creating more accurate, generalizable models. A holistic approach that combines technological advancements with personalized patient care and ongoing education is essential for addressing these challenges and improving spine surgery outcomes.

Decompression alone or with fusion for degenerative lumbar spondylolisthesis (Nordsten-DS): five year follow-up of a randomised, multicentre, non-inferiority trial

OBJECTIVE

To assess whether decompression alone is non-inferior to decompression with instrumented fusion five years after primary surgery in patients with degenerative lumbar spondylolisthesis.

DESIGN

Five year follow-up of a randomised, multicentre, non-inferiority trial (Nordsten-DS).

SETTING

16 public orthopaedic and neurosurgical clinics in Norway.

PARTICIPANTS

Patients aged 18-80 years with symptomatic lumbar spinal stenosis and a spondylolisthesis of 3 mm or more at the stenotic level.

INTERVENTIONS

Decompression surgery alone and decompression with additional instrumented fusion (1:1).

MAIN OUTCOME MEASURES

The primary outcome was a 30% or more reduction in Oswestry disability index from baseline to five year follow-up. The predefined non-inferiority margin was a -15 percentage point difference in the proportion of patients who met the primary outcome. Secondary outcomes included the mean change in Oswestry disability index, Zurich claudication questionnaire, numeric rating scale for leg and back pain, and EuroQol Group 5-Dimension (EQ-5D-3L) questionnaire.

RESULTS

From 12 February 2014 to 18 December 2017, 267 participants were randomly assigned to decompression alone (n=134) and decompression with instrumented fusion (n=133). Of these, 230 (88%) responded to the five year questionnaire: 121 in the decompression group and 109 in the fusion group. Mean age at baseline was 66.2 years (SD 7.6), and 69% were women. In the modified intention-to-treat analysis with multiple imputation of missing data, 84 (63%) of 133 people in the decompression alone group and 81 (63%) of 129 people in the fusion group had a at least a 30% reduction in Oswestry disability index, a difference of 0.4 percentage points. (95% confidence interval (CI) -11.2 to 11.9). The respective results of the per protocol analysis were 65 (65%) of 100 in the decompression alone group and 59 (66%) of 89 in the fusion group, a difference of -1.3 percentage points (95% CI -14.5 to 12.2). Both 95% CIs were higher than the predefined non-inferiority margin of -15%. The mean change in Oswestry disability index from baseline to five years was -17.8 in both groups (mean difference 0.02 (95% CI -3.8 to 3.9)). Results of the other secondary outcomes were in the same direction as the primary outcome. From two to five year follow-up, a new lumbar operation occurred in six (5%) of 123 people in the decompression group and 11 (10%) of 113 people in the fusion group, with a total from baseline to five years of 21 (16%) of 129 people and 23 (18%) of 125, respectively.

CONCLUSIONS

In participants with degenerative spondylolisthesis, decompression alone was non-inferior to decompression with instrumented fusion five years after primary surgery. Proportions of subsequent surgeries at the index level or an adjacent lumbar level were no different between the groups.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02051374.

Can local application of vancomycin reduce surgical site infection rate after open lumbar fusion surgery?: A multicenter retrospective cohort study

Surgical site infection (SSI) after posterior open lumbar fusion (POLF) is a major concern for both surgeons and patients. We sought to explore whether local application of vancomycin could decrease the rate of SSI. We reviewed the clinical data of patients who underwent POLF between June 2015 and June 2022 at 3 spinal centers. Patients were divided into those who received local vancomycin (vancomycin group) and those who did not (non-vancomycin group). The SSI rates at 12 months postoperatively were compared between the 2 groups. Although a trend toward a lower infection rate was observed in the vancomycin group than in the non-vancomycin group; the difference was not statistically significant (3.6% vs 5.5%, P = .121). However, we found that the postoperative SSI rate was significantly lower in the vancomycin group than in the non-vancomycin group (4.9% vs 11.4%, P = .041) in patients ≥ 2 fused segments, while there was no significant difference in postoperative SSI rate in patients with single fusion segment (3.1% vs 3.6%, P = .706). The logistic regression analysis indicated that the SSI rate in the non-vancomycin group was approximately 2.498 times higher than that in the vancomycin group (P = .048, odds ratio: 2.498, 95% confidence interval: 1.011-6.617) in patients with ≥2 fused segments. In SSI patients with confirmed pathogens, the SSI rate of Gram-negative bacteria in the vancomycin group was significantly higher than that in the non-vancomycin group (10/14 [71.4%] vs 5/22 [31.8%]), whereas the SSI rate of Gram-positive bacteria in the vancomycin group was significantly lower than that in the non-vancomycin group (4/14 [28.6%] vs 15/22 [68.2%]). Local administration of vancomycin is recommended in patients with ≥2 fused segments as it may facilitate to reduce the postoperative rate of SSI after POLF. Additionally, the local use of vancomycin can decrease the Gram-positive bacterial infections but is not effective against Gram-negative infections, which indirectly leads to an increase in the proportion of Gram-negative infections in SSI patients with confirmed pathogens.

Lumbar Decompression With and Without Fusion for Lumbar Stenosis With Spondylolisthesis: A Cost Utility Analysis

STUDY DESIGN

Markov model.

OBJECTIVE

To compare the cost-effectiveness of lumbar decompression alone (DA) with lumbar decompression with fusion (DF) for the management of adults undergoing surgery for lumbar stenosis with associated degenerative spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Rates of lumbar fusion have increased for all indications in the United States over the last 20 years. Recent randomized controlled trial data, however, have suggested comparable functional outcomes and lower reoperation rates for lumbar decompression and fusion as compared with DA in the treatment of lumbar stenosis with degenerative spondylolisthesis.

MATERIALS AND METHODS

A multistate Markov model was constructed from the US payer perspective of a hypothetical cohort of patients with lumbar stenosis with associated spondylolisthesis requiring surgery. Data regarding clinical improvement, costs, and reoperation were generated from contemporary randomized trial evidence, meta-analyses of recent prospective studies, and large retrospective cohorts. Base case, one-way sensitivity analysis, and probabilistic sensitivity analyses were conducted, and the results were compared with a WTP threshold of $100,000 (in 2022 USD) over a two-year time horizon. A discount rate of 3% was utilized.

RESULTS

The incremental cost and utility of DF relative to DA were $12,778 and 0.00529 aggregated quality adjusted life years. The corresponding incremental cost-effectiveness ratio of $2,416,281 far exceeded the willingness to pay threshold of $100,000. In sensitivity analysis, the results varied the most with respect to rate of improvement after DA, rate of improvement after lumbar decompression and fusion, and odds ratio of reoperation between the two groups. Zero percent of one-way and probabilistic sensitivity analyses achieved cost-effectiveness at the willingness-to-pay threshold.

CONCLUSIONS

Within the context of contemporary surgical data, DF is not cost-effective compared with DA in the surgical management of lumbar stenosis with associated spondylolisthesis over a two-year time horizon.

Estimated number of spine surgeries and related deaths in Japan from 2014 to 2020

BACKGROUND

The total number of spine surgeries per year and their related deaths in Japan has not been adequately estimated in the literature.

METHODS

We retrospectively reviewed the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) between April 2014 to March 2021, which covers 99.9 % of health insurance claim receipts by general practitioners. The annual number of surgeries was counted using K codes, a procedure classification unique to Japan, and classified into the following six categories; percutaneous vertebroplasty, endoscopic surgery, open discectomy, laminoplasty/laminectomy, instrumentation surgery, and others. The data distribution was also summarized by sex and age. Additionally, by reviewing DPC database-related papers for evaluation of the mortality rate after spine surgery in Japan, the number of spine surgery-related deaths was calculated.

RESULTS

The NDB showed that the number of spine surgeries analyzed in this study increased from 170,081 in 2014 to 193,903 in 2019, with a slight decrease in 2020. The ratio of instrumentation surgery increased from 33.0 % in 2014 to 37.9 % in 2020. The rate of patients aged 75 or older increased 31.6 % to 39.6 %. Combining these findings with DPC data showing a mortality rate of 0.1 % to 0.4 % revealed that the estimated number of deaths related to spine surgery in Japan ranged from 200 to 800 per year.

CONCLUSIONS

Approximately 200,000 spine surgeries and 200 to 800 spine surgery-related inpatient deaths were estimated to have occurred in Japan around 2020.