Cost-effectiveness of the X-STOP® interspinous spacer for lumbar spinal stenosis

Innovative technologies in thoracolumbar and lumbar spine surgery failing to reach standard of care: state-of-art review

PURPOSE

To evaluate previously popular technologies in the field of spine surgery, and to better understand their advantages and limitations to the current standards of care. Spine surgery is an ever-evolving field that serves to resolve various spinal pathologies in patients of all ages. While there are established treatments for various conditions, such as lumbar spinal stenosis, idiopathic scoliosis, and degenerative lumbar disease, there is always further research and development in these areas to produce innovative technologies that can lead to better outcomes. As this process progresses, we must remind ourselves of previously tried and tested inventions and their outcomes that have fallen short of becoming a standard to ensure we are able to learn lessons from the past.

METHODS

A thorough literature review was conducted with the aim of compiling literature of previously utilized technologies in spine surgery. Biomedical databases were utilized to gather relevant articles including PubMed, MEDLINE, and EMBASE. Emphasis was placed on gathering articles with technologies or therapeutics aimed at treating common spinal pathologies including lumbar spinal stenosis (LSS), adolescent idiopathic scoliosis (AIS), and other degenerative lumbar spine diseases. The keywords used were: "failed technologies", "historical technologies", "spine surgery", "spinal stenosis", "adolescent idiopathic scoliosis", and "degenerative lumbar spine disease". A total of 47 articles were gathered after initial review.

RESULTS

Different technologies pertaining to spine surgery were identified and critically evaluated. Some of these technologies included X-STOP, Vertiflex, Vertebral Body Stapling, and Dynesys. These technologies were evaluated for their strengths and limitations across their spinal pathology applications. While each type of technology had their benefits, the data tended to be mixed with various limitations across studies.

CONCLUSION

These technologies have been trialed in the field of spine surgery across various spinal pathologies, but still prove of limited efficacy and shortcomings to the current standards of care.

Is the interspinous process device safe and effective in elderly patients with lumbar degeneration? A systematic review and meta-analysis of randomized controlled trials

BACKGROUND CONTEXT

Lumbar spinal stenosis is one of the most common diseases affecting the elderly that is characterized by the narrowing of the spinal canal and peripheral neural pathways which may cause back pain and neurogenic intermittent claudication in affected patients. Recently, as an alternative treatment between conservative therapy and decompression surgery, interspinous process device (IPD) such as X-stop, Coflex, DIAM, Aperius, Wallis, etc., has gained enough popularity.

PURPOSE

The purpose of this study was to evaluate the efficacy and safety of IPD in the treatment of degenerative lumbar spinal stenosis compared with decompression surgery.

STUDY DESIGN

This study was a systematic review and meta-analysis of randomized controlled trials.

PATIENT SAMPLE

555 patients' samples were collected for this study.

OUTCOME MEASURES

The Visual Analogue Scale and the Oswestry Disability Index were analyzed, as well as the Zurich Claudication Questionnaire For efficacy evaluation. Complication and reoperation rate was utilized for the assessment of safety.

METHODS

A comprehensive literature search was performed through Pubmed, EMBASE, Web of Science, and Cochrane Library until October 2023. Among the studies meeting the eligible criteria, any study in which IPD was utilized in the treatment of degenerative lumbar spinal stenosis was included in the current review. For efficacy evaluation, the Visual Analogue Scale and the Oswestry Disability Index were analyzed, as well as the Zurich Claudication Questionnaire. Complication and reoperation rates were utilized for the assessment of safety.

RESULTS

Five randomized controlled trials with 555 patients were included. There were no significant differences in VAS leg pain (SMD - 0.08, 95% CI - 0.32 to 0.15) and back pain (SMD 0.09, 95%CI-0.27 to 0.45), ODI scores (MD 1.08, 95% CI - 11.23 to 13.39) and ZCQ physical function (MD-0.09, 95% CI-0.22 to 0.05) for IPD compared with decompression surgery. In terms of ZCQ symptom severity (MD - 0.22, 95% CI - 0.27 to - 016), decompression surgery showed superior to the IPD. As for complications (RR 1.08, 95% CI 0.36 to 3.27), the IPD had no advantages compared to decompression surgery, whereas inferior to it in reoperation rate (RR 2.58, 95% CI 1.67 to 3.96).

CONCLUSIONS

This systematic review and meta-analysis indicated no superiority in the clinical outcome for IPD compared with decompression surgery. However, more clinical studies are warranted to determine the efficacy and safety of IPD.

Methodology of economic evaluations in spine surgery: a systematic review and qualitative assessment

OBJECTIVES

The present study is a systematic review conducted as part of a methodological approach to develop evidence-based recommendations for economic evaluations in spine surgery. The aim of this systematic review is to evaluate the methodology and quality of currently available clinical cost-effectiveness studies in spine surgery.

STUDY DESIGN

Systematic literature review.

DATA SOURCES

PubMed, Web of Science, Embase, Cochrane, Cumulative Index to Nursing and Allied Health Literature, EconLit and The National Institute for Health Research Economic Evaluation Database were searched through 8 December 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they met all of the following eligibility criteria: (1) spine surgery, (2) the study cost-effectiveness and (3) clinical study. Model-based studies were excluded.

DATA EXTRACTION AND SYNTHESIS

The following data items were extracted and evaluated: pathology, number of participants, intervention(s), year, country, study design, time horizon, comparator(s), utility measurement, effectivity measurement, costs measured, perspective, main result and study quality.

RESULTS

130 economic evaluations were included. Seventy-four of these studies were retrospective studies. The majority of the studies had a time horizon shorter than 2 years. Utility measures varied between the EuroQol 5 dimensions and variations of the Short-Form Health Survey. Effect measures varied widely between Visual Analogue Scale for pain, Neck Disability Index, Oswestry Disability Index, reoperation rates and adverse events. All studies included direct costs from a healthcare perspective. Indirect costs were included in 47 studies. Total Consensus Health Economic Criteria scores ranged from 2 to 18, with a mean score of 12.0 over all 130 studies.

CONCLUSIONS

The comparability of economic evaluations in spine surgery is extremely low due to different study designs, follow-up duration and outcome measurements such as utility, effectiveness and costs. This illustrates the need for uniformity in conducting and reporting economic evaluations in spine surgery.

Economic costs, health-related quality of life outcomes and cost-utility of a physical and psychological group intervention targeted at older adults with neurogenic claudication

BACKGROUND

Emerging evidence suggests that structured and progressive exercise underpinned by a cognitive behavioural approach can improve functional outcomes in patients with neurogenic claudication (NC). However, evidence surrounding its economic benefits is lacking.

OBJECTIVES

To estimate the economic costs, health-related quality of life outcomes and cost-effectiveness of a physical and psychological group intervention (BOOST programme) versus best practice advice (BPA) in older adults with NC.

METHODS

An economic evaluation was conducted based on data from a pragmatic, multicentre, superiority, randomised controlled trial. The base-case economic evaluation took the form of an intention-to-treat analysis conducted from a UK National Health Service (NHS) and personal social services (PSS) perspective and separately from a societal perspective. Costs (£ 2018-2019 prices) were collected prospectively over a 12 month follow-up period. A bivariate regression of costs and quality-adjusted life-years (QALYs), with multiple imputation of missing data, was conducted to estimate the incremental cost per QALY gained and the incremental net monetary benefit (INMB) of the BOOST programme in comparison to BPA. Sensitivity and pre-specified subgroup analyses explored uncertainty and heterogeneity in cost-effectiveness estimates.

RESULTS

Participants (N = 435) were randomised to the BOOST programme (n = 292) or BPA (n = 143). Mean (standard error [SE]) NHS and PSS costs over 12 months were £1,974 (£118) in the BOOST arm versus £1,827 (£169) in the BPA arm (p = 0.474). Mean (SE) QALY estimates were 0.620 (0.009) versus 0.599 (0.006), respectively (p = 0.093). The probability that the BOOST programme is cost-effective ranged between 67 and 83% (NHS and PSS perspective) and 79-89% (societal perspective) at cost-effectiveness thresholds between £15,000 and £30,000 per QALY gained. INMBs ranged between £145 and £464 at similar cost-effectiveness thresholds. The cost-effectiveness results remained robust to sensitivity analyses.

CONCLUSIONS

The BOOST programme resulted in modest QALY gains over the 12 month follow-up period. Future studies with longer intervention and follow-up periods are needed to address uncertainty around the health-related quality of life impacts and cost-effectiveness of such programmes. Trial registration This study has been registered in the International Standard Randomised Controlled Trial Number registry, reference number ISRCTN12698674. Registered on 10 November 2015.

Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of lumbar spinal stenosis, 2021 - Secondary publication

BACKGROUND

The Japanese Orthopaedic Association (JOA) guideline for the management of lumbar spinal stenosis (LSS) was first published in 2011. Since then, the medical care system for LSS has changed and many new articles regarding the epidemiology and diagnostics of LSS, conservative treatments such as new pharmacotherapy and physical therapy, and surgical treatments including minimally invasive surgery have been published. In addition, various issues need to be examined, such as verification of patient-reported outcome measures, and the economic effect of revised medical management of patients with lumbar spinal disorders. Accordingly, in 2019 the JOA clinical guidelines committee decided to update the guideline and consequently established a formulation committee. The purpose of this study was to describe the formulation we implemented for the revision of the guideline, incorporating the recent advances of evidence-based medicine.

METHODS

The JOA LSS guideline formulation committee revised the previous guideline based on the method for preparing clinical guidelines in Japan proposed by the Medical Information Network Distribution Service in 2017. Background and clinical questions were determined followed by a literature search related to each question. Appropriate articles based on keywords were selected from all the searched literature. Using prepared structured abstracts, systematic reviews and meta-analyses were performed. The strength of evidence and recommendations for each clinical question was decided by the committee members.

RESULTS

Eight background and 15 clinical questions were determined. Answers and explanations were described for the background questions. For each clinical question, the strength of evidence and the recommendation were both decided, and an explanation was provided.

CONCLUSIONS

The 2021 clinical practice guideline for the management of LSS was completed according to the latest evidence-based medicine. We expect that this guideline will be useful for all medical providers as an index in daily medical care, as well as for patients with LSS.

Microdiscectomy compared with transforaminal epidural steroid injection for persistent radicular pain caused by prolapsed intervertebral disc: the NERVES RCT

BACKGROUND

Sciatica is a common condition reported to affect > 3% of the UK population at any time and is most often caused by a prolapsed intervertebral disc. Currently, there is no uniformly adopted treatment strategy. Invasive treatments, such as surgery (i.e. microdiscectomy) and transforaminal epidural steroid injection, are often reserved for failed conservative treatment.

OBJECTIVE

To compare the clinical effectiveness and cost-effectiveness of microdiscectomy with transforaminal epidural steroid injection for the management of radicular pain secondary to lumbar prolapsed intervertebral disc for non-emergency presentation of sciatica of < 12 months' duration.

INTERVENTIONS

Patients were randomised to either (1) microdiscectomy or (2) transforaminal epidural steroid injection.

DESIGN

A pragmatic, multicentre, randomised prospective trial comparing microdiscectomy with transforaminal epidural steroid injection for sciatica due to prolapsed intervertebral disc with < 1 year symptom duration.

SETTING

NHS services providing secondary spinal surgical care within the UK.

PARTICIPANTS

A total of 163 participants (aged 16-65 years) were recruited from 11 UK NHS outpatient clinics.

MAIN OUTCOME MEASURES

The primary outcome was participant-completed Oswestry Disability Questionnaire score at 18 weeks post randomisation. Secondary outcomes were visual analogue scores for leg pain and back pain; modified Roland-Morris score (for sciatica), Core Outcome Measures Index score and participant satisfaction at 12-weekly intervals. Cost-effectiveness and quality of life were assessed using the EuroQol-5 Dimensions, five-level version; Hospital Episode Statistics data; medication usage; and self-reported cost data at 12-weekly intervals. Adverse event data were collected. The economic outcome was incremental cost per quality-adjusted life-year gained from the perspective of the NHS in England.

RESULTS

Eighty-three participants were allocated to transforaminal epidural steroid injection and 80 participants were allocated to microdiscectomy, using an online randomisation system. At week 18, Oswestry Disability Questionnaire scores had decreased, relative to baseline, by 26.7 points in the microdiscectomy group and by 24.5 points in the transforaminal epidural steroid injection. The difference between the treatments was not statistically significant (estimated treatment effect -4.25 points, 95% confidence interval -11.09 to 2.59 points). Nor were there significant differences between treatments in any of the secondary outcomes: Oswestry Disability Questionnaire scores, visual analogue scores for leg pain and back pain, modified Roland-Morris score and Core Outcome Measures Index score up to 54 weeks. There were four (3.8%) serious adverse events in the microdiscectomy group, including one nerve palsy (foot drop), and none in the transforaminal epidural steroid injection group. Compared with transforaminal epidural steroid injection, microdiscectomy had an incremental cost-effectiveness ratio of £38,737 per quality-adjusted life-year gained and a probability of 0.17 of being cost-effective at a willingness to pay threshold of £20,000 per quality-adjusted life-year.

LIMITATIONS

Primary outcome data was invalid or incomplete for 24% of participants. Sensitivity analyses demonstrated robustness to assumptions made regarding missing data. Eighteen per cent of participants in the transforaminal epidural steroid injection group subsequently received microdiscectomy prior to their primary outcome assessment.

CONCLUSIONS

To the best of our knowledge, the NErve Root Block VErsus Surgery trial is the first trial to evaluate the comparative clinical effectiveness and cost-effectiveness of microdiscectomy and transforaminal epidural steroid injection. No statistically significant difference was found between the two treatments for the primary outcome. It is unlikely that microdiscectomy is cost-effective compared with transforaminal epidural steroid injection at a threshold of £20,000 per quality-adjusted life-year for sciatica secondary to prolapsed intervertebral disc.

FUTURE WORK

These results will lead to further studies in the streamlining and earlier management of discogenic sciatica.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN04820368 and EudraCT 2014-002751-25.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 24. See the NIHR Journals Library website for further project information.

Cost-effectiveness and Safety of Interspinous Process Decompression (Superion)

Objective

There are several treatment options for patients suffering from lumbar spinal stenosis, including surgical and conservative care. Interspinous spacer decompression using the Superion device offers a less invasive procedure for patients who fail conservative treatment before traditional decompression surgery. This review assesses the current cost-effectiveness, safety, and performance of lumbar spinal stenosis treatment modalities compared with the Superion interspinous spacer procedure.

Methods

EMBASE and PubMed were searched to find studies reporting on the cost-effectiveness, safety, and performance of conservative treatment, including medicinal treatments, epidural injections, physical therapy, and alternative methods, as well as surgical treatment, including laminectomy, laminectomy with fusion, and interspinous spacer decompression. Results were supplemented with manual searches.

Results

Despite substantial costs, persistent conservative treatment (>12 weeks) of lumbar spinal stenosis showed only minimal improvement in pain and functionality. When conservative treatment fails, surgery is more effective than continuing conservative treatment. Lumbar laminectomy with fusion has considerably greater cost than laminectomy alone, as the length of hospital stay increases, the costs for implants are substantial, and complications increase. Although laminectomy and the Superion have comparable outcomes, the Superion implant is positioned percutaneously. This approach may minimize the direct and indirect costs of outpatient rehabilitation and absenteeism, respectively.

Conclusions

Superion interspinous lumbar decompression is a minimally invasive procedure for patients with lumbar spinal stenosis who have failed conservative treatment. Compared with extending conservative treatment or traditional spinal surgery, interspinous lumbar decompression reduces the direct and indirect costs associated with lumbar spinal stenosis.

Systematic Review of Decision Analytic Modelling in Economic Evaluations of Low Back Pain and Sciatica

BACKGROUND

Low back pain (LBP) and sciatica place significant burden on individuals and healthcare systems, with societal costs alone likely to be in excess of £15 billion. Two recent systematic reviews for LBP and sciatica identified a shortage of modelling studies in both conditions.

OBJECTIVES

The aim of this systematic review was to document existing model-based economic evaluations for the treatment and management of both conditions; critically appraise current modelling techniques, analytical methods, data inputs, and structure, using narrative synthesis; and identify unresolved methodological problems and gaps in the literature.

METHODS

A systematic literature review was conducted whereby 6512 records were extracted from 11 databases, with no date limits imposed. Studies were abstracted according to a predesigned protocol, whereby they must be economic evaluations that employed an economic decision model and considered any management approach for LBP and sciatica. Study abstraction was initially performed by one reviewer who removed duplicates and screened titles to remove irrelevant studies. Overall, 133 potential studies for inclusion were then screened independently by other reviewers. Consensus was reached between reviewers regarding final inclusion.

RESULTS

Twenty-one publications of 20 unique models were included in the review, five of which were modelling studies in LBP and 16 in sciatica. Results revealed a poor standard of modelling in both conditions, particularly regarding modelling techniques, analytical methods, and data quality. Specific issues relate to inappropriate representation of both conditions in terms of health states, insufficient time horizons, and use of inappropriate utility values.

CONCLUSION

High-quality modelling studies, which reflect modelling best practice, as well as contemporary clinical understandings of both conditions, are required to enhance the economic evidence for treatments for both conditions.

Interspinous process devices for treatment of degenerative lumbar spine stenosis: A systematic review and meta-analysis

BACKGROUND

Degenerative lumbar spinal stenosis is a condition related to aging in which structural changes cause narrowing of the central canal and intervertebral foramen. It is currently the leading cause for spinal surgery in patients over 65 years. Interspinous process devices (IPDs) were introduced as a less invasive surgical alternative, but questions regarding safety, efficacy, and cost-effectiveness are still unanswered.

OBJECTIVES

The aim of this study was to provide complete and reliable information regarding benefits and harms of IPDs when compared to conservative treatment or decompression surgery and suggest directions for forthcoming RCTs.

METHODS

We searched MEDLINE, EMBASE, Cochrane Library, Scopus, and LILACS for randomized and quasi-randomized trials, without language or period restrictions, comparing IPDs to conservative treatment or decompressive surgery in adults with symptomatic degenerative lumbar spine stenosis. Data extraction and analysis were conducted following the Cochrane Handbook. Primary outcomes were pain assessment, functional impairment, Zurich Claudication Questionnaire, and reoperation rates. Secondary outcomes were quality of life, complications, and cost-effectiveness. This systematic review was registered at Prospero (International prospective register of systematic reviews) under number 42015023604.

RESULTS

The search strategy resulted in 17 potentially eligible reports. At the end, nine reports were included and eight were excluded. Overall quality of evidence was low. One trial compared IPDs to conservative treatment: IPDs presented better pain, functional status, quality of life outcomes, and higher complication risk. Five trials compared IPDs to decompressive surgery: pain, functional status, and quality of life had similar outcomes. IPD implant presented a significantly higher risk of reoperation. We found low-quality evidence that IPDs resulted in similar outcomes when compared to standard decompression surgery. Primary and secondary outcomes were not measured in all studies and were often published in incomplete form. Subgroup analysis was not feasible. Difficulty in contacting authors may have prevented us of including data in quantitative analysis.

CONCLUSIONS

Patients submitted to IPD implants had significantly higher rates of reoperation, with lower cost-effectiveness. Future trials should improve in design quality and data reporting, with longer follow-up periods.

Utilization of Interspinous Devices Throughout the United States Over a Recent Decade: An Analysis of the Nationwide Inpatient Sample

STUDY DESIGN

Retrospective database study.

OBJECTIVES

Analysis of economic and demographic data concerning interspinous device (ID) placement throughout the United States to improve value-based care and health care utilization.

METHODS

The National Inpatient Sample (NIS) database was queried for patients who underwent insertion of an interspinous process spinal stabilization device (ICD-9-CM 84.80) between 2008 and 2014 across 44 states. Demographic and economic data were obtained which included the annual number of surgeries, age, sex, insurance type, location, and frequency of routine discharge. The NIS database represents a 20% sample of discharges from US hospitals, which is weighted to provide national estimates.

RESULTS

There was a 73% decrease in ID implanted from 2008 to 2014. The mean cost associated with insertion of the device increased 28% from $13 653 in 2008 to $17 515 in 2014. The mean length of stay (LOS) increased from 1.8 to 2.4 days. Patients aged 45 to 64 years increased from 14.1% to 34.3% while patients aged 65 to 84 years decreased from 74.4% to 60.6%. By region, 34% of ID placement occurred in the South followed by 19.7% that occured in the Northeast. When stratifying by median income for patient zip code, the procedure was performed more in cities designated as higher rather than lower income areas (74.2% and 19.5%, respectively).

CONCLUSIONS

Throughout the United States, there was a progressive decline in the insertion of interspinous spacers by 73% over the study period. The total costs for the procedure increased by 28% while the aggregate national charges decreased by 55.6% between 2008 and 2014.

Understanding the value of minimally invasive procedures for the treatment of lumbar spinal stenosis: the case of interspinous spacer devices

BACKGROUND CONTEXT

Minimally invasive lumbar spinal stenosis procedures have uncertain long-term value.

PURPOSE

This study sought to characterize factors affecting the long-term cost-effectiveness of such procedures using interspinous spacer devices ("spacers") relative to decompression surgery as a case study.

STUDY DESIGN

Model-based cost-effectiveness analysis.

PATIENT SAMPLE

The Medicare Provider Analysis and Review database for the years 2005-2009 was used to model a group of 65-year-old patients with spinal stenosis who had no previous spine surgery and no contraindications to decompression surgery.

OUTCOME MEASURES

Costs, quality-adjusted life years (QALYs), and cost per QALY gained were the outcome measures.

METHODS

A Markov model tracked health utility and costs over 10 years for a 65-year-old cohort under three care strategies: conservative care, spacer surgery, and decompression surgery. Incremental cost-effectiveness ratios (ICER) reported as cost per QALY gained included direct medical costsfor surgery. Medicare claims data were used to estimate complication rates, reoperation, and related costs within 3 years. Utilities and long-term reoperation rates for decompression were derived frompublished studies. Spacer failure requiring reoperation beyond 3 years and post-spacer health utilities are uncertain and were evaluated through sensitivity analyses. In the base-case, the spacer failure rate was held constant for years 4-10 (cumulative failure: 47%). In a "worst-case" analysis, the 10-year cumulative reoperation rate was increased steeply (to 90%). Threshold analyses were performed to determine the impact of failure and post-spacer health utility on the cost-effectiveness of spacer surgery.

RESULTS

The spacer strategy had an ICER of $89,500/QALY gained under base-case assumptions, and remained under $100,000 as long as the 10-year cumulative probability of reoperation did not exceed 54%. Under worst-case assumptions, the spacer ICER was $482,000/QALY and fell below $100,000 only if post-spacer utility was 0.01 greater than post-decompression utility or the cost of spacer surgery was $1,600 less than the cost of decompression surgery.

CONCLUSIONS

Spacers may provide a reasonably cost-effective initial treatment option for patients with lumbar spinal stenosis. Their value is expected to improve if procedure costs are lower in outpatient settings where these procedures are increasingly being performed. Decision analysis is useful for characterizing the long-term cost-effectiveness potential for minimally invasive spinal stenosis treatments and highlights the importance of complication rates and prospective health utility assessment.

Surgical options for lumbar spinal stenosis

BACKGROUND

Hospital charges for lumbar spinal stenosis have increased significantly worldwide in recent times, with great variation in the costs and rates of different surgical procedures. There have also been significant increases in the rate of complex fusion and the use of spinal spacer implants compared to that of traditional decompression surgery, even though the former is known to incur costs up to three times higher. Moreover, the superiority of these new surgical procedures over traditional decompression surgery is still unclear.

OBJECTIVES

To determine the efficacy of surgery in the management of patients with symptomatic lumbar spinal stenosis and the comparative effectiveness between commonly performed surgical techniques to treat this condition on patient-related outcomes. We also aimed to investigate the safety of these surgical interventions by including perioperative surgical data and reoperation rates.

SEARCH METHODS

Review authors performed electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, AMED, Web of Science, LILACS and three trials registries from their inception to 16 June 2016. Authors also conducted citation tracking on the reference lists of included trials and relevant systematic reviews.

SELECTION CRITERIA

This review included only randomised controlled trials that investigated the efficacy and safety of surgery compared with no treatment, placebo or sham surgery, or with another surgical technique in patients with lumbar spinal stenosis.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the studies for inclusion and performed the 'Risk of bias' assessment, using the Cochrane Back and Neck Review Group criteria. Reviewers also extracted demographics, surgery details, and types of outcomes to describe the characteristics of included studies. Primary outcomes were pain intensity, physical function or disability status, quality of life, and recovery. The secondary outcomes included measurements related to surgery, such as perioperative blood loss, operation time, length of hospital stay, reoperation rates, and costs. We grouped trials according to the types of surgical interventions being compared and categorised follow-up times as short-term when less than 12 months and long-term when 12 months or more. Pain and disability scores were converted to a common 0 to 100 scale. We calculated mean differences for continuous outcomes and relative risks for dichotomous outcomes. We pooled data using the random-effects model in Review Manager 5.3, and used the GRADE approach to assess the quality of the evidence.

MAIN RESULTS

We included a total of 24 randomised controlled trials (reported in 39 published research articles or abstracts) in this review. The trials included 2352 participants with lumbar spinal stenosis with symptoms of neurogenic claudication. None of the included trials compared surgery with no treatment, placebo or sham surgery. Therefore, all included studies compared two or more surgical techniques. We judged all trials to be at high risk of bias for the blinding of care provider domain, and most of the trials failed to adequately conceal the randomisation process, blind the participants or use intention-to-treat analysis. Five trials compared the effects of fusion in addition to decompression surgery. Our results showed no significant differences in pain relief at long-term (mean difference (MD) -0.29, 95% confidence interval (CI) -7.32 to 6.74). Similarly, we found no between-group differences in disability reduction in the long-term (MD 3.26, 95% CI -6.12 to 12.63). Participants who received decompression alone had significantly less perioperative blood loss (MD -0.52 L, 95% CI -0.70 L to -0.34 L) and required shorter operations (MD -107.94 minutes, 95% CI -161.65 minutes to -54.23 minutes) compared with those treated with decompression plus fusion, though we found no difference in the number of reoperations (risk ratio (RR) 1.25, 95% CI 0.81 to 1.92). Another three trials investigated the effects of interspinous process spacer devices compared with conventional bony decompression. These spacer devices resulted in similar reductions in pain (MD -0.55, 95% CI -8.08 to 6.99) and disability (MD 1.25, 95% CI -4.48 to 6.98). The spacer devices required longer operation time (MD 39.11 minutes, 95% CI 19.43 minutes to 58.78 minutes) and were associated with higher risk of reoperation (RR 3.95, 95% CI 2.12 to 7.37), but we found no difference in perioperative blood loss (MD 144.00 mL, 95% CI -209.74 mL to 497.74 mL). Two trials compared interspinous spacer devices with decompression plus fusion. Although we found no difference in pain relief (MD 5.35, 95% CI -1.18 to 11.88), the spacer devices revealed a small but significant effect in disability reduction (MD 5.72, 95% CI 1.28 to 10.15). They were also superior to decompression plus fusion in terms of operation time (MD 78.91 minutes, 95% CI 30.16 minutes to 127.65 minutes) and perioperative blood loss (MD 238.90 mL, 95% CI 182.66 mL to 295.14 mL), however, there was no difference in rate of reoperation (RR 0.70, 95% CI 0.32 to 1.51). Overall there were no differences for the primary or secondary outcomes when different types of surgical decompression techniques were compared among each other. The quality of evidence varied from 'very low quality' to 'high quality'.

AUTHORS' CONCLUSIONS

The results of this Cochrane review show a paucity of evidence on the efficacy of surgery for lumbar spinal stenosis, as to date no trials have compared surgery with no treatment, placebo or sham surgery. Placebo-controlled trials in surgery are feasible and needed in the field of lumbar spinal stenosis. Our results demonstrate that at present, decompression plus fusion and interspinous process spacers have not been shown to be superior to conventional decompression alone. More methodologically rigorous studies are needed in this field to confirm our results.

Market approval processes for new types of spinal devices: challenges and recommendations for improvement

BACKGROUND

Spinal pathology and related symptoms are among the most common health problems and are associated with high health care costs and productivity losses. Due to the aging population, these costs are further increasing every year. Another important reason for the increasing costs is the market approval of new technologies, such as spinal devices that are usually more expensive than the existing technologies. Previous cases of medical device failure led to concern about possible deficiencies in the market approval process.

OBJECTIVE

The objective is to provide an overview of U.S. Food and Drug Administration (FDA) regulation regarding spinal implants to delineate the challenges and opportunities that spine surgery currently faces.

METHODS

In this paper, two cases of market entries of spinal devices are presented and evaluated to illustrate these deficiencies.

RESULTS

Spinal implant regulation is facing several challenges. New spinal devices should increase patient outcomes and safety at reasonable societal costs. The main challenge is to have a rigorous evaluation before dissemination, while still leaving room for innovative behavior that thrusts the healthcare practice forward.

CONCLUSION

We have provided recommendations to enhance spinal implant regulation and improve and ensure the patient's safety and the future of spine surgery.

Cost-effectiveness of minimally invasive sacroiliac joint fusion

BACKGROUND

Sacroiliac joint (SIJ) disorders are common in patients with chronic lower back pain. Minimally invasive surgical options have been shown to be effective for the treatment of chronic SIJ dysfunction.

OBJECTIVE

To determine the cost-effectiveness of minimally invasive SIJ fusion.

METHODS

Data from two prospective, multicenter, clinical trials were used to inform a Markov process cost-utility model to evaluate cumulative 5-year health quality and costs after minimally invasive SIJ fusion using triangular titanium implants or non-surgical treatment. The analysis was performed from a third-party perspective. The model specifically incorporated variation in resource utilization observed in the randomized trial. Multiple one-way and probabilistic sensitivity analyses were performed.

RESULTS

SIJ fusion was associated with a gain of approximately 0.74 quality-adjusted life years (QALYs) at a cost of US$13,313 per QALY gained. In multiple one-way sensitivity analyses all scenarios resulted in an incremental cost-effectiveness ratio (ICER) <$26,000/QALY. Probabilistic analyses showed a high degree of certainty that the maximum ICER for SIJ fusion was less than commonly selected thresholds for acceptability (mean ICER =$13,687, 95% confidence interval $5,162-$28,085). SIJ fusion provided potential cost savings per QALY gained compared to non-surgical treatment after a treatment horizon of greater than 13 years.

CONCLUSION

Compared to traditional non-surgical treatments, SIJ fusion is a cost-effective, and, in the long term, cost-saving strategy for the treatment of SIJ dysfunction due to degenerative sacroiliitis or SIJ disruption.

Cost-effectiveness of three treatment strategies for lumbar spinal stenosis: Conservative care, laminectomy, and the Superion interspinous spacer

BACKGROUND

Lumbar spinal stenosis is a painful and debilitating condition resulting in healthcare costs totaling tens of billions of dollars annually. Initial treatment consists of conservative care modalities such as physical therapy, NSAIDs, opioids, and steroid injections. Patients refractory to these therapies can undergo decompressive surgery, which has good long-term efficacy but is more traumatic and can be associated with high post-operative adverse event (AE) rates. Interspinous spacers have been developed to offer a less-invasive alternative. The objective of this study was to compare the costs and quality adjusted life years (QALYs) gained of conservative care (CC) and decompressive surgery (DS) to a new minimally-invasive interspinous spacer.

METHODS

A Markov model was developed evaluating 3 strategies of care for lumbar spinal stenosis. If initial therapies failed, the model moved patients to more invasive therapies. Data from the Superion FDA clinical trial, a prospective spinal registry, and the literature were used to populate the model. Direct medical care costs were modeled from 2014 Medicare reimbursements for healthcare services. QALYs came from the SF-12 PCS and MCS components. The analysis used a 2-year time horizon with a 3% discount rate.

RESULTS

CC had the lowest cost at $10,540, while Spacers and DS were nearly identical at about $13,950. CC also had the lowest QALY increase (0.06), while Spacers and DS were again nearly identical (.28). The incremental cost-effectiveness ratios (ICER) for Spacers compared to CC was $16,300 and for DS was $15,200.

CONCLUSIONS

Both the Spacer and DS strategies are far below the commonly cited $50,000/QALY threshold and produced several times the QALY increase versus CC, suggesting that surgical care provides superior value (cost / effectiveness) versus sustained conservative care in the treatment of lumbar spinal stenosis.

Comparing cost-effectiveness of X-Stop with minimally invasive decompression in lumbar spinal stenosis: a randomized controlled trial

STUDY DESIGN

Randomized clinical trial with 2-year follow-up.

OBJECTIVE

To compare the cost-effectiveness of X-stop to minimally invasive decompression in patients with symptomatic lumbar spinal stenosis.

SUMMARY OF BACKGROUND DATA

Lumbar spinal stenosis is the most common indication for operative treatment in elderly. Although surgery is more costly than nonoperative treatment, health outcomes for more than 2 years were shown to be significantly better. Surgical treatment with minimally invasive decompression is widely used. X-stop is introduced as another minimally invasive technique showing good results compared with nonoperative treatment.

METHODS

We enrolled 96 patients aged 50 to 85 years, with symptoms of neurogenic intermittent claudication within 250-m walking distance and 1- or 2-level lumbar spinal stenosis, randomized to either minimally invasive decompression or X-stop. Quality-adjusted life-years were based on EuroQol EQ-5D. The hospital unit costs were estimated by means of the top-down approach. Each cost unit was converted into a monetary value by dividing the overall cost by the amount of cost units produced. The analysis of costs and health outcomes is presented by the incremental cost-effectiveness ratio.

RESULTS

The study was terminated after a midway interim analysis because of significantly higher reoperation rate in the X-stop group (33%). The incremental cost for X-stop compared with minimally invasive decompression was &OV0556;2832 (95% confidence interval: 1886-3778), whereas the incremental health gain was 0.11 quality-adjusted life-year (95% confidence interval: -0.01 to 0.23). Based on the incremental cost and effect, the incremental cost-effectiveness ratio was &OV0556;25,700.

CONCLUSION

The majority of the bootstrap samples displayed in the northeast corner of the cost-effectiveness plane, giving a 50% likelihood that X-stop is cost-effective at the extra cost of &OV0556;25,700 (incremental cost-effectiveness ratio) for a quality-adjusted life-year. The significantly higher cost of X-stop is mainly due to implant cost and the significantly higher reoperation rate.

LEVEL OF EVIDENCE

2.

Cost-utility analyses in spine care: a qualitative and systematic review

STUDY DESIGN

Systematic review.

OBJECTIVE

A systematic review was performed to identify US-based cost-utility analyses (CUA) studies in spine care and to critically evaluate the quality of the available literature.

SUMMARY OF BACKGROUND DATA

There has been a recent trend in the United States toward increased publication of economic analyses in spine care. The cost-effectiveness of spine interventions and the quality of published literature is not well understood.

METHODS

A MEDLINE search was conducted to identify cost analyses in spine care. Articles were excluded on the basis of the following criteria: nonspine care, nonoperative, non-US based, nonclinical, and not CUA. Of the 424 screened articles, 20 met inclusion criteria. Quality of studies was assessed using the Quality of Health Economic Studies instrument.

RESULTS

Evidence for the cost-effectiveness of operative spinal intervention is varied. The majority of available studies report favorable cost-effectiveness ratios, however, a few studies suggest that certain operative interventions are not cost-effective. Average Quality of Health Economic Studies score of all included studies was 75.1 (60-93). The quality of evidence is variable and there are a number of weaknesses in the available literature, most significant of which is that few studies adopt a long-term time horizon or have sufficient follow-up (N = 3/20). High Quality of Health Economic Studies scoring studies were more likely to have sensitivity analysis (P = 0.016), societal cost perspective (P = 0.014), and a funding disclosure (P = 0.03).

CONCLUSION

There is a small but rapidly growing body of US-based CUA in spine care. The quality of CUA evidence is variable but there are significant opportunities to strengthen future CUA studies in spine. This study highlights the need for more attention to CUA research and the quality of these studies in spine care.

Cost-effective studies in spine surgeries: a narrative review

BACKGROUND CONTEXT

Although the pathologic processes that affect the spine remain largely unchanged, our techniques to correct them continue to evolve with the development of novel medical and surgical interventions. Although the primary purpose of new technologies is to improve patients' quality of life, the economic impact of such therapies must be considered.

PURPOSE

To review the available peer-reviewed literature on spine surgery that addresses the cost-effectiveness of various treatments and technologies.

STUDY DESIGN

A narrative literature review.

METHODS

Articles published between January 1, 2000 and December 31, 2012 were selected from two Pubmed searches using keywords cost-effectiveness AND spine (216 articles) and cost analysis AND spine (358 articles). Relevant articles on cost analyses and cost-effectiveness were selected by the authors and reviewed.

RESULTS

Cervical and lumbar surgeries (anterior cervical discectomy and fusion, standard open lumbar discectomy, and standard posterior lumbar laminectomy) are reasonably cost effective at 2 years after the procedure (<100,000 US dollars per quality-adjusted life years gained) and become more cost effective with time because of sustained clinical improvements with relatively low additional incurred costs. The usage of transfusion avoidance technology is not cost effective because of the low risk of complications associated with allogenic transfusions. Although intraoperative neuromonitoring and imaging modalities are both cost saving and cost-effective, their cost-effectiveness is largely dependent on the baseline rate of neurologic complications and implant misplacement, respectively. More rigorous studies are needed to evaluate the cost-effectiveness of recombinant bone morphogenetic protein.

CONCLUSIONS

An ideal new technology should be able to achieve maximal improvement in patient health at a cost that society is willing to pay. The cost-effectiveness of technologies and treatments in spine care is dependent on their durability and the rate and severity of the baseline clinical problem that the treatment was designed to address.

Comparison of the efficacy and safety between interspinous process distraction device and open decompression surgery in treating lumbar spinal stenosis: a meta analysis

OBJECTIVES

The present study performed a meta-analysis to evaluate the efficacy and safety of interspinous process distraction device (IPD) compared with open decompression surgery (ODS) in treating lumbar spinal stenosis.

METHODS

Literatures were searched in the databases including Cochrane Library, Pubmed, OvidSP, Sciencedirect, Web of Science, and Springerlin. Published reviews were checked to track missed original research papers. The quality and bias of publications with randomized controlled trial were evaluated using the tool for assessing risk of bias in the Cochrane handbook. The quality and bias of publications with cohort trial were evaluated using the Newcastle-Ottawa Scale. The grades of literatures were evaluated with the guidelines of Grading of Recommendations Assessment Development and Evaluation (GRADE).

RESULTS

Totally, 21 publications matched the inclusion criteria, including 20 different clinical trials and 54,138 patients. The results indicated that there was no significant difference in improvement rate, Oswestry disability index questionnaire (ODI) score, and visual analog scale (VAS) score of back pain or leg pain between IPD group and ODS group. The postoperation complication rate, perioperation blood loss, hospitalization time, and operation time were lower/shorter in IPD group than ODS group. However, the reoperation rate in IPD group was higher than ODS group.

CONCLUSION

The results indicated that IPD has better effects and less complication than ODS. However, because of the higher reoperation rate in IPD than ODS, we failed to conclude that IPD could replace ODS as golden standard but may be a viable alternative in treating lumbar spinal stenosis.

Controversies about interspinous process devices in the treatment of degenerative lumbar spine diseases: past, present, and future

A large number of interspinous process devices (IPD) have been recently introduced to the lumbar spine market as an alternative to conventional decompressive surgery in managing symptomatic lumbar spinal pathology, especially in the older population. Despite the fact that they are composed of a wide range of different materials including titanium, polyetheretherketone, and elastomeric compounds, the aim of these devices is to unload spine, restoring foraminal height, and stabilize the spine by distracting the spinous processes. Although the initial reports represented the IPD as a safe, effective, and minimally invasive surgical alternative for relief of neurological symptoms in patients with low back degenerative diseases, recent studies have demonstrated less impressive clinical results and higher rate of failure than initially reported. The purpose of this paper is to provide a comprehensive overview on interspinous implants, their mechanisms of action, safety, cost, and effectiveness in the treatment of lumbar stenosis and degenerative disc diseases.

X-stop versus decompressive surgery for lumbar neurogenic intermittent claudication: randomized controlled trial with 2-year follow-up

STUDY DESIGN

Prospective randomized controlled study.

OBJECTIVE

To compare the outcome of indirect decompression by means of the X-Stop (Medtronics Inc., Minneapolis, MN) implant with conventional decompression in patients with neurogenic intermittent claudication due to lumbar spinal stenosis.

SUMMARY OF BACKGROUND DATA

Decompression is currently the "gold standard" for lumbar spinal stenosis but is afflicted with complications and a certain number of dissatisfied patients. Interspinous implants have been on the market for more than 10 years, but no prospective study comparing its outcome with decompression has been performed.

METHODS

After power calculation, 100 patients were included: 50 in the X-Stop group and 50 in the decompression group. Patients with symptomatic 1- or 2-level lumbar spinal stenosis and neurogenic claudication relieved on flexion were included. X-Stop operations were performed under local anesthesia.The mean patient age was 69 (49-89) years, and the male/female distribution was 56/44. Minimal dural sac area was in all cases except two 80 mm or less.The noninferiority hypothesis included 6, 12, and 24 months of follow-up, and included. intention-to-treat as well as as-treated analyses.The primary outcome meansure was the Zürich Claudication Questionnaire, and the secondary outcome measures was the visual analogue scale pain, Short-Form 36 (SF-36), complications, and reoperations.

RESULTS

The primary and secondary outcome measures of patients in both groups improved significantly. The results were similar at 6, 12, and 24 months and at no time point could any statistical difference between the 2 types of surgery be identified. Three patients (6%) in the decompression group underwent further surgery, compared with 13 patients (26%) in the X-Stop group (P = 0.04). Results were identical in intention-to-treat and as-treated analyses.

CONCLUSION

For spinal stenosis with neurogenic claudication, decompressive surgery as well as X-Stop are appropriate procedures. Similar results were achieved in both groups, however, with a higher number of reoperations in the X-Stop group. Patients having X-Stop removal and decompression experienced results similar to those randomized to primary decompression.

LEVEL OF EVIDENCE

1.