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

Longitudinal Analysis of the Care Pathway of Patients with Lumbar Spinal Stenosis in the US

Background

Evidence regarding the frequency and timing of treatment for lumbar spinal stenosis (LSS) fails to offer clear consensus. We describe the LSS care journey from initial diagnosis to first surgical intervention.

Methods

Using Medicare claims database from 2009 through 2020, we identified patients who were diagnosed with LSS. The use and timing of conservative and surgical treatments during the entire follow-up from the initial diagnosis were reported.

Results

Of the 143,849 patients identified, 68% received conservative care within 8.4 months and 25.3% received a surgical or minimally invasive intervention over 5.7 years following initial diagnosis, with 12.6% undergoing open decompression alone, 10.2% undergoing open decompression with fusion, and 5.1% undergoing fusion surgery alone. Fewer than 1% were provided with interspinous spacers or a percutaneous image-guided lumbar decompression.

Conclusion

Approximately three-quarters of patients in the study received no surgical or non-invasive interventions for approximately six years following diagnosis with LSS.

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.

Comparison analysis of safety outcomes and the rate of subsequent spinal procedures between interspinous spacer without decompression versus minimally invasive lumbar decompression

INTRODUCTION

Treatment for degenerative lumbar spinal stenosis (LSS) typically begins with conservative care and progresses to minimally invasive procedures, including interspinous spacer without decompression or fusion (ISD) or minimally invasive lumbar decompression (MILD). This study examined safety outcomes and the rate of subsequent spinal procedures among LSS patients receiving an ISD versus MILD as the first surgical intervention.

METHODS

100% Medicare Standard Analytical Files were used to identify patients with an ISD or MILD (first procedure=index date) from 2017 to 2021. ISD and MILD patients were matched 1:1 using propensity score matching based on demographics and clinical characteristics. Safety outcomes and subsequent spinal procedures were captured from index date until end of follow-up. Cox models were used to analyze rates of subsequent surgical interventions, LSS-related interventions, open decompression, fusion, ISD, and MILD. Cox models were used to assess postoperative complications during follow-up and logistic regression to analyze life-threatening complications within 30 days of index procedure.

RESULTS

A total of 3682 ISD and 5499 MILD patients were identified. After matching, 3614 from each group were included in the analysis (mean age=74 years, mean follow-up=20.0 months). The risk of undergoing any intervention, LSS-related intervention, open decompression, and MILD were 21%, 28%, 21%, and 81% lower among ISD compared with MILD patients. Multivariate analyses showed no significant differences in the risk of undergoing fusion or ISD, experiencing postoperative complications, or life-threatening complications (all p≥0.241) between the cohorts.

CONCLUSIONS

These results showed ISD and MILD procedures have an equivalent safety profile. However, ISDs demonstrated lower rates of open decompression and MILD.

Dyspnoea at the end of life: instrument development and validation-the CONFORTO Strategy

OBJECTIVE

To describe the construction and validation of the algorithm for Criteria for inclusion; Objective of dyspnoea; Notification of patient/family/health professionals; Facial air flow; Oxygen; Relaxion and breathing; Treating causes of dyspnoea and Opioid (CONFORTO), an instrument to guide health professionals in managing dyspnoea in patients with an advance stage of the disease at the end-of-life.

METHODS

The study was carried out in three stages: (1) literature review and construction of CONFORTO; (2) semantic validation; (3) application of the CONFORTO Strategy to health professionals as a test (before video lessons) and post-test (20 days after watching video lessons) methodology. The scores obtained in the pretest and post-test were compared using the Wilcoxon test.

RESULTS

Seventy-four professionals from different internal medicine and intensive care units participated in the study. The CONFORTO Strategy involved eight acronym-forming items: Criteria for inclusion; Objective of dyspnoea; Notification of patient/family/health professionals; Facial air flow; Oxygen; Relaxion and breathing; Treating causes of dyspnoea and Opioid. The post-test indicated a significant increase in the score for the following items: facial air flow (p=0.016); oxygen (p=0.002); relaxation and breathing (p=0.002) and treating the causes of dyspnoea (p=0.011). The increase in score occurred after the training sessions with video lessons.

CONCLUSION

The CONFORTO Strategy proved valid and reliable for managing dyspnoea in patients with an advanced stage of the disease at the end-of-life. Because the instrument is easy-to-use, it can be used by the entire health team at any assistance-providing location, and can, thus, contribute to improving dyspnoea management for these patients.

Prospective 5-year follow-up of L5-S1 versus L4-5 midline decompression and interspinous-interlaminar fixation as a stand-alone treatment for spinal stenosis compared with laminectomies

Background

Spinal stenosis treatment includes laminectomies with or without fusion or with interspinous distraction with or without fixation. Lack of published data on interspinous fixation devices (IFD) at L5-S1 is less considered as an option due to the smaller anatomical S1 spinous process and the higher stresses from the immobile sacrum. Our objective was to evaluate the outcomes of an IFD used as a stand-alone treatment for spinal stenosis at L5-S1 and L4-5 compared to historical data on open laminectomies.

Methods

Prospective comparative cohort study (Level 2) looking at collected preoperatively and postoperatively Visual Analog Scores (VAS) and Oswestry Disability Index (ODI) data, complications, and revision rates on 100 consecutive patients with spinal stenosis treated with midline decompression and InSpan (InSpan LLC, Malden, MA, USA) IFD, at L5-S1 and L4-5, up to five-year follow-up. All patients were treated by a single surgeon in an academic private practice. Historical published outcome data for open laminectomies were compared.

Results

Among the 100 patients, 45 underwent surgery at L5-S1 with a mean VAS pain score that decreased by 75% and ODI improved by 63% (P<0.001). Fifty-five patients had surgery at L4-5 with mean VAS and ODI scores improved by 80% and 66% (P<0.001) respectively. Preoperative and postoperative ODI and preoperative VAS scores were similar at L5-S1 and L4-5, however, postoperative VAS scores were significantly less for L4-5 versus L5-S1 (P<0.01). All surgeries were completed in less than one hour. There was a total of one L4-5 revision (1.8%) and two L5-S1 revisions (4.4%). Comparable laminectomy data showed decrease in VAS and ODI scores by 51% and 62% (P<0.05). The reoperation rate for laminectomies at five to ten years varied up to 24%.

Conclusions

Spinal stenosis patients treated with midline decompression and InSpan IFD, used as a stand-alone treatment for interspinous-interlaminar fixation, at L4-5 and L5-S1, showed improved outcome scores and low complication and revision rates at five years and were comparable to historical open laminectomy data. InSpan is a successful substitute for laminectomies in selected patients and was performed in less than 60 minutes. We recommend choosing the appropriately sized implant to achieve adequate distraction decompression to avoid recurrent symptoms.

Longitudinal Comparative Analysis of Complications and Subsequent Interventions Following Stand-Alone Interspinous Spacers, Open Decompression, or Fusion for Lumbar Stenosis

INTRODUCTION

For individuals with lumbar spinal stenosis (LSS), minimally invasive procedures such as an interspinous spacer device without decompression or fusion (ISD) or open surgery (i.e., open decompression or fusion) may relieve symptoms and improve functions when patients fail to respond to conservative therapies. This research compares longitudinal postoperative outcomes and rates of subsequent interventions between LSS patients treated with ISD and those with open decompression or fusion as their first surgical intervention.

METHODS

This retrospective, comparative claims analysis identified patients age ≥ 50 years with LSS diagnosis and with a qualifying procedure during 2017-2021 in the Medicare database which includes healthcare encounters in inpatient and outpatient settings. Patients were followed from the qualifying procedure until end of data availability. The outcomes assessed during the follow-up included subsequent surgical interventions, including subsequent fusion and lumbar spine surgeries, long-term complications, and short-term life-threatening events. Additionally, the costs to Medicare during a 3-year follow-up were calculated. Cox proportional hazards, logistic regression, and generalized linear models were used to compare outcomes and costs, adjusted for baseline characteristics.

RESULTS

A total of 400,685 patients who received a qualifying procedure were identified (mean age 71.5 years, 50.7% male). Compared to ISD patients, patients receiving open surgery (i.e., decompression and/or fusion) were more likely to have a subsequent fusion [hazard ratio (HR), 95% confidence intervals (CI): 1.49 (1.17, 1.89)-2.54 (2.00, 3.23)] or other lumbar spine surgery [HR (CI): 3.05 (2.18, 4.27)-5.72 (4.08, 8.02)]. Short-term life-threatening events [odds ratio (CI): 2.42 (2.03, 2.88)-6.36 (5.33, 7.57)] and long-term complications [HR (CI): 1:31 (1.13, 1.52)-2.38 (2.05, 2.75)] were more likely among the open surgery cohorts. Adjusted mean index costs were lowest for decompression alone (US$7001) and highest for fusion alone ($33,868). ISD patients had significantly lower 1-year complication-related costs than all surgery cohorts and lower 3-year all-cause costs than fusion cohorts.

CONCLUSIONS

ISD resulted in lower risks of short- and long-term complications and lower long-term costs than open decompression and fusion surgeries as a first surgical intervention for LSS.

Minimally Invasive Spine Surgery: An Overview

Spinal surgery is undergoing a major transformation toward a minimally invasive paradigm. This shift is being driven by multiple factors, including the need to address spinal problems in an older and sicker population, as well as changes in patient preferences and reimbursement patterns. Increasingly, minimally invasive surgical techniques are being used in place of traditional open approaches due to significant advancements and implementation of intraoperative imaging and navigation technologies. However, in some patients, due to specific anatomic or pathologic factors, minimally invasive techniques are not always possible. Numerous algorithms have been described, and additional efforts are underway to better optimize patient selection for minimally invasive spinal surgery (MISS) procedures in order to achieve optimal outcomes. Numerous unique MISS approaches and techniques have been described, and several have become fundamental. Investigators are evaluating combinations of MISS techniques to further enhance the surgical workflow, patient safety, and efficiency.

Best Practices for Minimally Invasive Lumbar Spinal Stenosis Treatment 2.0 (MIST): Consensus Guidance from the American Society of Pain and Neuroscience (ASPN)

Introduction

Methods

Results

Discussion

Conclusion

Decompression Using Minimally Invasive Surgery for Lumbar Spinal Stenosis Associated with Degenerative Spondylolisthesis: A Review

Lumbar spinal stenosis (LSS), which often occurs concurrently with degenerative spondylolisthesis (DS), is a common disease in the elderly population, affecting the quality of life of aged people significantly. Notwithstanding the frequently good effect of conservative therapy on LSS, a minority of the patients ultimately require surgery. Surgery for LSS aims to decompress the narrowed spinal canals with preservation of spinal stability. Traditional open surgery, either pure decompression or decompression with fusion, was considered effective for the treatment of LSS with or without DS. However, the long-term clinical outcomes of traditional open surgery are still unclear. Moreover, the disadvantages of conventional open surgery are extensive, examples including tissue injuries or secondary instability, with limited outcomes and significant reoperation rates. With the development and improvement of surgical tools, various minimally invasive spine surgery (MISS) methods, including indirect decompression techniques of interspinous process devices (IPDs) and direct decompression techniques such as microscopic spine surgery or endoscopic spine surgery (ESS), have been updated with enhancement. IPDs, such as Superion devices, were reported to behave with comparable physical function, disability, and symptoms outcomes to laminectomy decompression. As an emerging technique of MISS, ESS has beneficial hallmarks including minimal tissue injuries, reduced complication rates, and shortened recovery periods, thus gaining popularity in recent years. ESS can be classified in terms of endoscopic hallmarks and approaches. Predictably, with the continuous development and gradual maturity, MISS is expected to replace traditional open surgery widely in the surgical treatment of LSS associated with DS in the future.

A Radiological Evaluation of Lumbar Spinous Processes and Interspinous Spaces, Including Clinical Implications

Background and objective

The aim of this study was the examination of morphometry of the spinous process (SP) and interspinous space (ISS) of the lumbar region to help provide a basis for the design and implantation of interspinous devices.

Methods

Between 2017 and 2019, 215 individuals underwent magnetic resonance imaging of the lumbar region for various reasons. No pathology was detected in these images, and the participants' age, height, and weight information when available were included in the study. From these images, the height and length of the SP and ISS in the lumbar region were noted. The heights of the SP and ISS were measured at three levels as anterior, middle, and posterior (respectively, anterior height of the spinous process [AHSP], middle height of the spinous process [MHSP], as well as posterior height of the spinous process [PHSP] for the height of SP, and anterior ISS, middle ISS and posterior ISS for the height of ISS). All measurements were compared according to the gender, age, weight, height, and body mass index of the individuals.

Results

The level with the lowest SP height and length was L5 vertebra. The ISS height and length were lowest at L4-L5. In addition, we observed a statistically significant difference at multiple levels with age, weight, height, and body mass index of the reference ranges.

Conclusion

We think that these changes should be considered when designing and implanting interspinous devices. Since there are few studies examining all these correlations, we think that the results of this study will make a unique contribution to the literature.

Comparison of Adverse Outcomes Following Placement of Superion Interspinous Spacer Device Versus Laminectomy and Laminotomy

BACKGROUND

Current evidence suggests placement of the Superion interspinous spacer (SISS) device compared with laminectomy or laminotomy surgery offers an effective, less invasive treatment option for patients with symptomatic lumbar spinal stenosis. Both SISS placement and laminectomy or laminotomy have risks of complications and a direct comparison of complications between the 2 procedures has not been previously studied. The purpose of this study is to compare the short-term complications of the SISS with laminectomy or laminotomy and highlight device-specific long-term outcomes with SISS.

METHODS

Via retrospective review, 189 patients who received lumbar level SISSs were compared with 378 matched controls who underwent primary lumbar spine laminectomy or laminotomy; data were collected from the American College of Surgeons National Surgical Quality Improvement Program database. Complications analyzed included rates of wound infection, pulmonary embolism, deep venous thrombosis, urinary tract infection, sepsis, septic shock, cardiac arrest, death, and reoperation within 30 days of index surgery. Differences between groups were analyzed using the χ²test. Device-specific complication (DSC) rates included device malfunction or misplacement (DM), device explantation (DE), spinous process fracture (SPF), and subsequent spinal surgery (SSS).

RESULTS

No differences in demographics or comorbidities existed between groups. There was no significant difference in rates of complications between groups. A total of 44.4% of patients in the SISS group experienced DSCs with 11.1% of patients experiencing DM, 21.1% experiencing an SPF, 20.1% requiring DE, and 24.3% requiring SSS. Having at least 1 DSC significantly increased odds of SSS, odds ratio >120, P < .0001.

CONCLUSION

Rates of 30-day complications in the SISS group were not significantly different from patients undergoing laminectomy or laminotomy. Rates of 2-year DSC within SISS and cumulative risk associated with these complications should be considered further as they likely represent need for additional procedures for patients and substantial cost to the healthcare system.

LEVEL OF EVIDENCE

4.

CLINICAL RELEVANCE

Having no differences in adverse events between laminectomies or laminotomies and SISS plus evidence of substantial device-specific long-term adverse outcomes and reoperation should be given consideration when deciding on surgical intervention of 1-2 level lumbar spinal stenosis.