Cost-effectiveness analysis of treatments for vertebral compression fractures

Spinal infection after vertebral augmentation: a covert complication with serious havoc

INTRODUCTION

Vertebral augmentation, including percutaneous vertebroplasty (PVP) or kyphoplasty (PKP), is the current least invasive surgical option and has been widely used to treat the painful osteoporotic vertebral compression fractures (OVCF). However, the postoperative infections could be life-threatening, even though they rarely occur. Our studies aim to clarify the causation and outcomes of spinal infections following augmentation and meanwhile to identify the risk factors.

METHODS

A retrospective study was conducted on patients with OVCF who underwent PVP or PKP, and were subsequently admitted to our institution with postoperative spinal infection between January 2010 and December 2022. A total of 33 patients were finally included.

RESULTS

The rate of spinal infection after augmentation in our single institute was 0.05% (2/3893). In addition to these 2 patients, the remaining 31 were referred from other hospitals. All 33 patients exhibited elevated inflammatory parameters, 14 patients presented with fever, and 9 patients experienced neurological deficits. Additionally, 29 patients had comorbidity and risk factors. Pathogens were identified in 26 patients, while only 7 patients were examined as culture negative. 27 patients underwent revision surgery and 6 patients only received conservative therapy. Anterior surgery was performed in 2 patients, while posterior surgery was performed in 20 patients. A combined anterior-posterior surgery was performed in 5 patients. At the final follow-up, 18 patients had unrestricted mobility, 10 patients required assistance from crutches or a walker for ambulation, 4 patients needed a wheelchair, and 1 patients died after revision surgery.

CONCLUSIONS

Spinal infection after vertebral augmentation is rare, but it cannot be ignored. Surgeons should make every effort to detect the potential preoperative spondylitis or discitis. Once postoperative spinal infection is confirmed, a prompt intravenous antibiotic therapy is warranted. If medication therapy fails, revision surgery involving debridement and spinal reconstruction should be considered.

Vertebral augmentation: an overview

Vertebral compression fractures (VCFs) are a common pathologic process seen in 30-50% of individuals over the age of 50 years. Historically, VCFs were first treated with nonsurgical management while vertebral augmentation was reserved for severe cases resulting in deformity or significant disability. Current treatment algorithms based on established appropriateness criteria have changed recommendations towards supporting early vertebral augmentation for the VCFs causing the most clinically difficulty and taking into account the degree of vertebral body height loss, kyphotic deformity, and the degree of clinical progression. Percutaneous vertebroplasty (PVP) involves injecting primarily polymethacrylate (PMMA) bone cement directly into the cancellous bone of the vertebral body. There is recent literature showing the effectiveness of PVP including data comparing vertebroplasty to sham treatment. Vertebroplasty evolved into balloon kyphoplasty (BKP) where a balloon is first inserted into the vertebral body to create a cavity and reduce the fracture followed by an injection of bone cement. Both PVP and BKP have been shown to be significantly more effective at treatment of VCFs compared to nonsurgical management. The benefits shown in the literature have been demonstrated randomized control trials, cohort matched trials, post-market trials, registries, and many other data sources with approximately 250 manuscripts produced per year dedicated to the topic of vertebral augmentation.

Treatment progress of spinal metastatic cancer: a powerful tool for improving the quality of life of the patients

Spinal metastasis is a common secondary malignant tumor of the bone, often resulting in spinal cord and nerve root compression, leading to obvious pain and related compression symptoms. This condition has a high incidence and mortality rate. The treatment approach for most patients with spinal metastasis is primarily palliative. Consultation with a multidisciplinary team is widely accepted as a comprehensive treatment approach for patients with spinal metastases. With advancements in research and technology, the evaluation and treatment of spinal metastatic cancer are continuously evolving. This study provides an overview of surgical treatment, minimally invasive treatment, and radiotherapy for spinal metastatic cancer and also analyzes the clinical effects, advantages, and current limitations associated with various treatment approaches.

Cost-effectiveness and willing-to-pay thresholds for vertebral augmentation of osteoporotic vertebral fractures, what are they based on: a systematic review

OBJECTIVE

Although there is substantial clinical evidence on the safety and effectiveness of vertebral augmentation for osteoporotic vertebral fractures, cost-effectiveness is less well known. The objective of this study is to provide a systematic review of cost-effectiveness studies and policy-based willingness-to-pay (WTP) thresholds for different vertebral augmentation (VA) procedures, vertebroplasty (VP) and balloon kyphoplasty (BK), for osteoporotic vertebral fractures (OVFs).

DESIGN

A systematic review targeting cost-effectiveness studies of VA procedures for OVFs.

DATA SOURCES

Six bibliographic databases were searched from inception up to May 2021.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Studies were eligible if meeting all predefined criteria: (1) VP or BK intervention, (2) OVFs and (3) cost-effectiveness study. Articles not written in English, abstracts, editorials, reviews and those reporting only cost data were excluded.

DATA EXTRACTION AND SYNTHESIS

Information was extracted on study characteristics, cost-effective estimates, summary decisions and payer WTP thresholds. Incremental cost-effective ratio (ICER) was the main outcome measure. Studies were summarised by a structured narrative synthesis organised by comparisons with conservative management (CM). Two independent reviewers assessed the quality (risk of bias) of the systematic review and cost-effectiveness studies by peer-reviewed checklists.

RESULTS

We identified 520 references through database searching and 501 were excluded as ineligible by titles and abstract. Ten reports were identified as eligible from 19 full-text reviews. ICER for VP versus CM evaluated as cost per quality-adjusted life-year (QALY) ranged from €22 685 (*US$33 395) in Netherlands to £-2240 (*US$-3273), a cost-saving in the UK. ICERs for BK versus CM ranged from £2706 (*US$3954) in UK to kr600 000 (*US$90 910) in Sweden. ICERs were within payer WTP thresholds for a QALY based on historical benchmarks.

CONCLUSIONS

Both VP and BK were judged cost-effective alternatives to CM for OVFs in economic studies and were within WTP thresholds in multiple healthcare settings.

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.

Cost-effectiveness studies of vertebral augmentation for osteoporotic vertebral fractures: a systematic review

BACKGROUND CONTEXT

Osteoporotic vertebral fractures (OVF) dramatically increase with age and are serious life altering adverse events for seniors resulting in increased rates of institutionalization, morbidity and mortality. Given the expanding population of the elderly and increasing prevalence of OVFs, cost-effective treatment strategies need to be considered. Percutaneous vertebral augmentation (VA) procedures such as vertebroplasty (VP) or balloon kyphoplasty (BK) are increasingly employed to treat painful vertebral fractures not responding to conservative management (CM) of bedrest and analgesia. Both VA procedures have been shown to be effective treatments for OVFs in multiple systematic reviews of randomized controlled trials. In this systematic review, analytical strategies, designs and results were compared for health economic studies evaluating cost-effectiveness of VA procedures, VP or BK for OVFs. Furthermore, assessments of quality (risk of bias) were conducted for the systematic review and the individual studies with peer-reviewed checklists recommended for cost-effectiveness studies.

PURPOSE

To provide an up-to-date systematic review of peer-reviewed studies evaluating cost-effectiveness of VA procedures, VP or KP for OVFs to support treatment and health care funding decisions.

STUDY DESIGN

This study is a systematic literature review and structured narrative synthesis.

STUDY SAMPLE

Peer reviewed health economic studies reporting cost-effectiveness for VA procedures, VP or BK for OVFs OUTCOME MEASURES: The following information extracted from the studies included: report country and year, study design, comparators, population, perspective, health valuations, costing sources and cost-effectiveness measures. For economic studies involving modeling, information was also extracted for model type, time horizon, key model drivers, and handling of uncertainty. Incremental cost-effectiveness ratio (ICER), the ratio of differences between comparator treatment groups in costs and health benefits, was considered the main cost-effectiveness measure.

METHODS

A systematic review was conducted of MEDLINE, EMBASE, CINAHL, ECONLIT, Cochrane Library and DARE databases up to the review date May 2021. Studies were reviewed for those reporting cost-effectiveness analyses on VA procedures including VP or BK for OVFs. Studies including only costs, abstracts, editorials, methodologies and reviews were not included. The selection of articles was reported in line with PRISMA guidance. A descriptive framework was developed to classify types of cost-effectiveness studies based on methodological differences and a structured narrative synthesis was used to summarize studies. Quality assessments were made with British Medical Journal checklist for individual cost-effectiveness studies and the CiCERO checklist for systematic reviews of cost-effectiveness studies.

RESULTS

In this systematic review, 520 references were identified through database searching and 501 were excluded as ineligible by titles and abstract based on prior eligibility criteria. From full-text reviews of 19 reports, ten were identified as eligible for the systematic review evaluating cost-effectiveness of VA procedures for OVFs. All references were published between 2008 and 2020. The ten cost-effectiveness studies, three for VP, three for BK and four for both VP and BK, all involved CM for OVFs as a treatment comparator. The studies involved different methods of economic analysis, modeling assumptions, cost and health valuations conducted in different health care setting over different time periods. A framework for the review outlines key features of cost-effectiveness study designs consisting of unmatched, matched, or randomized controls involving cost-effectiveness or cost-utility) analyses. Both VP and BK were cost-effective alternatives to CM for OVFs with earlier health gains and significantly shorter hospital stays. Cost-effectiveness estimates, ICERs, remained relatively stable and within willingness-to-pay thresholds under a range of sensitivity analyses. Comparisons between VP and BK were variable depending on modeling assumptions, but generally the procedures had similar health benefit gains with VP having lower acute procedural costs.

CONCLUSIONS

Both VP and BK, have been shown to be cost-effective alternatives to CM for osteoporotic vertebral fractures in diverse cost-effectiveness studies conducted in multiple health care settings. Trial-based cost-utility contributed the strongest evidence supporting cost-effectiveness determination for VP and BK for OVFs.

Clinical Therapy of Metastatic Spinal Tumors

Metastatic spinal tumors (MST) have high rates of morbidity and mortality. MST can destroy the vertebral body or compress the nerve roots, resulting in an increased risk of pathological fractures and intractable pain. Here, we elaborately reviewed the currently available therapeutic options for MST according to the following four aspects: surgical management, minimally invasive therapy (MIT), radiation therapy, and systemic therapy. In particular, these aspects were classified and introduced to show their developmental process, clinical effects, advantages, and current limitations. Furthermore, with the improvement of treatment concepts and techniques, we discovered the prevalent trend toward the use of radiation therapy and MIT in clinic therapies. Finally, the future directions of these treatment options were discussed. We hoped that along with future advances and study will lead to the improvement of living standard and present status of treatment in patients with MST.

Cost-effectiveness of balloon kyphoplasty and vertebroplasty versus conservative medical management in the USA

The cost-effectiveness of surgical versus conservative medical management of vertebral compression fractures in the US was analyzed in the context of inpatient versus outpatient treatment. Surgical intervention (balloon kyphoplasty and vertebroplasty) was found to be cost-effective relative to conservative medical management at a US willingness-to-pay threshold.

INTRODUCTION

To date, only one published study has evaluated the cost-effectiveness (C/E) of balloon kyphoplasty (BKP) or vertebroplasty (VP) in US Medicare patients with osteoporotic vertebral compression fractures. This study further evaluates the C/E of surgical treatment vs. conservative medical management (CMM), expanding on prior modeling by accounting for quality-adjusted life-years gained.

METHODS

A Markov microsimulation model of 1000 patients was constructed. Cost data were based on an analysis of Medicare claims payments, with propensity-score matching performed for BKP and VP vs. controls (CMM). Mortality inputs were based on US life tables, modified to account for age at initial fracture, presence of subsequent fracture(s), and relative risk of mortality by treatment. Separate incremental cost-effectiveness ratios (ICERs) were calculated for BKP and VP in inpatient and outpatient surgical treatment locations to account for individual clinical profiles presenting to each.

RESULTS

The discounted ICER for inpatient BKP vs. CMM was $43,455 per QALY gained; for outpatient BKP vs. CMM, $10,922; for inpatient VP vs. CMM, $39,774; and for outpatient VP vs. CMM, $12,293. Probabilistic sensitivity analysis confirmed that both BKP and VP would be considered C/E vs. CMM at a US willingness-to-pay (WTP) threshold of $50,000/QALY in 80% and 100% of 500 model simulations, respectively. The most sensitive parameters included quality of life estimates and hazard ratios for mortality.

CONCLUSION

While VP and BKP are more expensive treatment options than CMM in the short term, model results suggest interventional treatment is cost-effective, among patients eligible for surgery, at a US WTP threshold. This conclusion supports those from economic analyses conducted in EU-member countries.

Percutaneous vertebroplasty and balloon kyphoplasty in the treatment of osteoporotic vertebral fractures: a prospective randomized comparison

PURPOSE

The purpose of this study is to compare the efficacy and safety of percutaneous vertebroplasty (PVP) and balloon kyphoplasty (BKP) in the treatment of osteoporotic vertebral compression fractures.

MATERIALS AND METHODS

Patients with osteoporotic vertebral body fractures (T4-L5) were randomized and not blinded to kyphoplasty (n = 69) or vertebroplasty (n = 70). The postoperative pain score (VAS) at 12 months was the primary end point. The radiographic results were evaluated in relation to the resolution of the fracture and the possible onset of further osteoporotic fractures during follow-up.

RESULTS

A total of one hundred and thirty-nine patients were eligible for randomization (n = 70 for PVP group and n = 69 for BKP), and twenty-six patients (twenty in the BKP group and six in the PVP group) were excluded. The mean average age of patients was 73 years, and 82% of the patients were females. VAS pain score was significantly reduced after surgery in both groups, and there were no significant differences between the two groups in postoperative VAS score. There was a significant reduction in kyphotic wedge angle and improvement of the sagittal index in both groups, but there was no significant difference between the two groups. There was a significant higher risk incidence of adjacent level fractures in the vertebroplasty group.

CONCLUSIONS

In terms of clinical outcomes, there were no differences between the two groups. Both showed a significant clinical improvement, vertebral body height restoration and reduction in the kyphotic angle. There was a significant higher risk of adjacent level fractures in the vertebroplasty group.

Percutaneous Vertebroplasty: A History of Procedure, Technology, Culture, Specialty, and Economics

Percutaneous vertebroplasty (VP) progressed from a virtually unknown procedure to one performed on hundreds of thousands of patients annually. The development of VP provides a historically exciting case study into a rapidly adopted procedure. VP was the synthesis of information gained from spinal biopsy developments, the inception of biomaterials used in medicine, and the unique health care climate in France during the 1980s. It was designed as a revolutionary technique to treat vertebral body fractures with minimal side effects and was rapidly adopted and marketed in the United States. The impact of percutaneous vertebroplasty on spine surgery was profound.

Current Concepts in the Management of Vertebral Compression Fractures

PURPOSE OF REVIEW

This comprehensive review of current concepts in the management of vertebral compression fractures is a manuscript of vertebral augmentation literature of risk factors, clinical presentation, and management. The objective of this review is to compare outcomes between multiple augmentation techniques and ongoing discussions of effectiveness of vertebral augmentation procedures.

RECENT FINDINGS

Vertebral compression fractures (VCFs) are a prevalent disease affecting approximately 1.5 million US adults annually. VCFs can cause severe physical limitations, including back pain, functional disability, and progressive kyphosis of the thoracic spine that ultimately results in decreased appetite, poor nutrition, impaired pulmonary function, and spinal cord compression with motor and sensory deficits. The deconditioning that affects patients with vertebral compression fractures leads to mortality at a far higher rate than age-matched controls. The management of vertebral compression fractures has been extensively discussed with opponents arguing in favor or restricting conservative management and against augmentation, while proponents argue in favor of augmentation. The literature is well established in reference to the effects on mortality when patients undergo treatment with vertebral augmentation; in over a million patients with vertebral compression fractures treated with vertebral augmentation as compared with patients treated with non-surgical management, the patients receiving augmentation performed well with a decrease in morbidity and mortality. Summary of the literature review shows that understanding the risk factors, appropriate clinical evaluation, and management strategies are crucial. Analysis of the evidence shows, based on level I and II studies, balloon kyphoplasty had significantly better and vertebroplasty tended to have better pain reduction compared with non-surgical management. In addition, balloon kyphoplasty tended to have better height restoration than vertebroplasty.

Long-term safety and clinical performance of kyphoplasty and SpineJack® procedures in the treatment of osteoporotic vertebral compression fractures: a pilot, monocentric, investigator-initiated study

This pilot monocenter study in 30 patients with painful osteoporotic vertebral compression fractures compared two vertebral augmentation procedures. Over a 3-year post-surgery follow-up, pain/disability/quality of life remained significantly improved with both balloon kyphoplasty and SpineJack® techniques, but the latter allowed better vertebral body height restoration/kyphosis correction.

INTRODUCTION

Patient follow-up rarely exceed 2 years in trials comparing vertebral augmentation procedures for the treatment of painful osteoporotic vertebral compression fractures (VCFs). This pilot, investigator-initiated, prospective study aimed to compare long-term results of SpineJack® (SJ) and balloon kyphoplasty (BKP). Preliminary results showed that SJ resulted in a better restoration of vertebral heights and angles, maintained over 12 months.

METHODS

Thirty patients were randomized to SJ (n = 15) or BKP (n = 15). Clinical endpoints were analgesic consumption, back pain intensity (visual analog scale (VAS)), the Oswestry Disability Index (ODI), and quality of life (EQ-VAS score). They were recorded preoperatively, at 5 days (except EQ-VAS), 1, 3, 6, 12, and 36 months post-surgery. Spine X-rays were taken 48 h prior to the procedure and 5 days, 6, 12, and 36 months after.

RESULTS

Clinical improvements were observed with both procedures over the 3-year period without significant inter-group differences, but the final mean EQ-5D_index score was significantly in favor of the SJ group (0.93 ± 0.11 vs 0.81 ± 0.09; p = 0.007). Vertebral height restoration/kyphotic correction was still evident at 36 months with a greater mean correction of anterior (10 ± 13% vs 2 ± 8% for BKP, p = 0.007) and central height (10 ± 11% vs 3 ± 7% for BKP, p = 0.034) and a larger correction of the vertebral body angle (- 5.0° ± 5.1° vs 0.4° ± 3.4°; p = 0.003) for SJ group.

CONCLUSIONS

In this study, both techniques displayed very good long-term clinical efficiency and safety in patients with osteoporotic VCFs. Over the 3-year follow-up, vertebral body height restoration/kyphosis correction was better with the SpineJack® procedure.

ISASS Policy 2018-Vertebral Augmentation: Coverage Indications, Limitations, and/or Medical Necessity

The ISASS Policy Statement on vertebral augmentation has the objectives to provide a background and an update with the latest clinical evidence for the international spine community. A SpineLine Panel Review (2010) appropriately recommended an exploration of "the seeming disconnect between the conclusions of … two [Level I] PRCT's and previous experience and data" regarding vertebral augmentation. ISASS responded by supporting a comprehensive meta-analysis to help frame a cogent historical analysis of vertebral augmentation. This ISASS Policy 2018 is based on a thorough literature search for relevant studies, including systematic reviews and meta-analyses, that are subjected to thorough quality appraisal for the purpose of informing public opinion and decision making. Given the abundance of high-quality information, ISASS can confidently advocate that there is strong support for vertebral augmentation in the treatment of symptomatic vertebral compression fractures.

Safety and clinical performance of kyphoplasty and SpineJack(®) procedures in the treatment of osteoporotic vertebral compression fractures: a pilot, monocentric, investigator-initiated study

Clinical performance and safety of two percutaneous vertebral cement augmentation (VA) procedures (SpineJack® and Kyphx Xpander® balloon) were compared in patients with osteoporotic compression fractures. Both techniques were safe, efficient, and led to a rapid and marked improvement in clinical signs; nevertheless, SpineJack showed better restoration of vertebral heights and angles, maintained over time.

INTRODUCTION

In patients with osteoporotic vertebral compression fractures (VCFs), both SpineJack® (SJ) and balloon kyphoplasty (BKP) led to a rapid and marked improvement in clinical signs. This pilot, monocentric, investigator-initiated, prospective study aimed to compare two percutaneous vertebral augmentation procedures in the painful osteoporotic VCF treatment.

METHODS

Thirty patients were randomized to receive SJ (n = 15) or BKP (n = 15). Analgesic consumption, back pain intensity (visual analog scale (VAS)), and Oswestry Disability Index (ODI) scores were recorded preoperatively, at 5 days and 1, 3, 6, and 12 months post-surgery. Quality of life (EQ-VAS score) was evaluated at 1, 3, 6, and 12 months. Spine X-rays were taken 48 h prior to procedure and 5 days and 6 and 12 months after.

RESULTS

SpineJack® led to a significantly shorter intervention period (23 vs 32 min; p < 0.001), a strong, rapid, and long-lasting decline in pain (94 vs 82 % at 12 months) and in functional disability (94 vs 90 % at 12 months), a greater and sustainable mean correction of anterior (12 ± 13 vs 0 ± 7 % for BKP, p = 0.003) and central height (12 ± 10 vs 2 ± 6 % for BKP, p = 0.001) at 12 months, and a larger restoration of the vertebral body angle still evident 12 months after implantation (-4.4° ± 5.8° vs 0.2° ± 3.0° for BKP; p = 0.012).

CONCLUSIONS

This pilot study showed that both techniques were safe and efficient for the osteoporotic VCF treatment. Radiological results indicate that the SpineJack® procedure has a higher potential for vertebral body height restoration and maintenance over time.

The Effectiveness of Percutaneous Vertebroplasty Is Determined by the Patient-Specific Bone Condition and the Treatment Strategy

Purpose

Vertebral fragility fractures are often treated by injecting bone cement into the collapsed vertebral bodies (vertebroplasty). The mechanisms by which vertebroplasty induces pain relief are not completely understood yet and recent debates cast doubt over the outcome of the procedure. The controversy is intensified by inconsistent results of randomized clinical trials and biomechanical studies that have investigated the effectiveness or the change in biomechanical response due to the reinforcement. The purpose of this study was to evaluate the effectiveness of vertebroplasty, by varying the relevant treatment parameters and (a) computationally predicting the improvement of the fracture risk depending on the chosen treatment strategy, and (b) identifying the determinants of a successful treatment.

Methods

A Finite Element model with a patient-specific failure criterion and direct simulation of PMMA infiltration in four lumbar vertebrae was used to assess the condition of the bone under compressive load before and after the virtual treatment, simulating in a total of 12000 virtual treatments.

Results

The results showed that vertebroplasty is capable of reducing the fracture risk by magnitudes, but can also have a detrimental effect. Effectiveness was strongly influenced by interactions between local bone quality, cement volume and injection location. However, only a moderate number of the investigated treatment strategies were able to achieve the necessary improvement for preventing a fracture.

Conclusions

We conclude that the effectiveness of vertebroplasty is sensitive to the patient’s condition and the treatment strategy.

Vertebral Augmentation for Osteoporotic Compression Fractures

Vertebral augmentation procedures such as vertebroplasty and kyphoplasty were developed to reduce pain and improve quality of life for patients with osteoporotic vertebral compression fractures. However, the use of vertebral augmentation has been debated and questioned since its inception. This article addresses some of these issues.

A Systematic Review of the Level of Evidence in Economic Evaluations of Medical Devices: The Example of Vertebroplasty and Kyphoplasty

CONTEXT

Economic evaluations are far less frequently reported for medical devices than for drugs. In addition, little is known about the quality of existing economic evaluations, particularly for innovative devices, such as those used in vertebroplasty and kyphoplasty.

OBJECTIVE

To assess the level of evidence provided by the available economic evaluations for vertebroplasty and kyphoplasty.

DATA SOURCES

A systematic review of articles in English or French listed in the MEDLINE, PASCAL, COCHRANE and National Health Service Economic Evaluation databases, with limits on publication date (up to the date of the review, March 2014).

STUDY SELECTION

We included only economic evaluations of vertebroplasty or kyphoplasty. Editorial and methodological articles were excluded.

DATA EXTRACTION

Data were extracted from articles by two authors working independently and using two analysis grids to measure the quality of economic evaluations.

DATA SYNTHESIS

Twenty-one studies met our inclusion criteria. All were published between 2008 and 2014. Eighteen (86%) were full economic evaluations. Cost-effectiveness analysis (CEA) was the most frequent type of economic evaluation, and was present in 11 (52%) studies. Only three CEAs complied fully with the British Medical Journal checklist. The quality of the data sources used in the 21 studies was high, but the CEAs conforming to methodological guidelines did not use high-quality data sources for all components of the analysis.

CONCLUSIONS

This systematic review shows that the level of evidence in economic evaluations of vertebroplasty and kyphoplasty is low, despite the recent publication of a large number of studies. This finding highlights the challenges to be faced to improve the quality of economic evaluations of medical devices.

Randomized controlled trial of vertebroplasty versus kyphoplasty in the treatment of vertebral compression fractures

BACKGROUND

We present the results of a randomized controlled trial evaluating the efficacy of vertebroplasty versus kyphoplasty in treating vertebral body compression fractures.

METHODS

Patients with vertebral body compression fractures were randomly assigned to treatment with kyphoplasty or vertebroplasty. Primary endpoints were pain (0-10 scale) and disability assessed using the Roland-Morris Disability Questionnaire (RMDQ). Outcomes were assessed at 3 days, 1 month, 6 months, and 1 year following the procedure.

RESULTS

115 subjects were enrolled in the trial with 59 (51.3%) randomly assigned to kyphoplasty and 56 (48.7%) assigned to vertebroplasty. Mean (SD) pain scores at baseline, 3 days, 30 days, and 1 year for kyphoplasty versus vertebroplasty were 7.4 (1.9) vs 7.9 (2.0), 4.1 (2.8) vs 3.7 (3.0), 3.4 (2.5) vs 3.6 (2.9), and 3.0 (2.8) vs 2.3 (2.6), respectively (p>0.05 at all time points). Mean (SD) RMDQ scores at baseline, 3 days, 30 days, 180 days, and 1 year were 17.3 (6.6) vs 16.3 (7.4), 11.8 (7.9) vs 10.9 (8.2), 8.6 (7.2) vs 8.8 (8.5), 7.9 (7.4) vs 7.3 (7.7), 7.5 (7.2) vs 6.7 (8.0), respectively (p>0.05 at all time points). For baseline to 12-month assessment in average pain and RMDQ scores, the standardized effect size between kyphoplasty and vertebroplasty was small at -0.36 (95% CI -1.02 to 0.31) and -0.04 (95% CI -1.68 to 1.60), respectively.

CONCLUSIONS

Our study indicates that vertebroplasty and kyphoplasty appear to be equally effective in substantially reducing pain and disability in patients with vertebral body compression fractures.

TRIAL REGISTRATION NUMBER

NCT00279877.

KAST Study: The Kiva System As a Vertebral Augmentation Treatment-A Safety and Effectiveness Trial: A Randomized, Noninferiority Trial Comparing the Kiva System With Balloon Kyphoplasty in Treatment of Osteoporotic Vertebral Compression Fractures

STUDY DESIGN

The KAST (Kiva Safety and Effectiveness Trial) study was a pivotal, multicenter, randomized control trial for evaluation of safety and effectiveness in the treatment of patients with painful, osteoporotic vertebral compression fractures (VCFs).

OBJECTIVE

The objective was to demonstrate noninferiority of the Kiva system to balloon kyphoplasty (BK) with respect to the composite primary endpoint.

SUMMARY OF BACKGROUND DATA

Annual incidence of osteoporotic VCFs is prevalent. Optimal treatment of VCFs should address pain, function, and deformity. Kiva is a novel implant for vertebral augmentation in the treatment of VCFs.

METHODS

A total of 300 subjects with 1 or 2 painful osteoporotic VCFs were randomized to blindly receive Kiva (n = 153) or BK (n = 147). Subjects were followed through 12 months. The primary endpoint was a composite at 12 months defined as a reduction in fracture pain by at least 15 mm on the visual analogue scale, maintenance or improvement in function on the Oswestry Disability Index, and absence of device-related serious adverse events. Secondary endpoints included cement usage, extravasation, and adjacent level fracture.

RESULTS

A mean improvement of 70.8 and 71.8 points in the visual analogue scale score and 38.1 and 42.2 points in the Oswestry Disability Index was noted in Kiva and BK, respectively. No device-related serious adverse events occurred. Despite significant differences in risk factors favoring the control group at baseline, the primary endpoint demonstrated noninferiority of Kiva to BK. Analysis of secondary endpoints revealed superiority with respect to cement use and site-reported extravasation and a positive trend in adjacent level fracture warranting further study.

CONCLUSION

The KAST study successfully established that the Kiva system is noninferior to BK based on a composite primary endpoint assessment incorporating pain-, function-, and device-related serious adverse events for the treatment of VCFs due to osteoporosis. Kiva was shown to be noninferior to BK and revealed a positive trend in several secondary endpoints.

LEVEL OF EVIDENCE

1.

Outcomes of vertebroplasty compared with kyphoplasty: a systematic review and meta-analysis

Background and purpose

Many studies demonstrate that both kyphoplasty and vertebroplasty are superior to conservative therapy in the treatment of osteoporotic vertebral body compression fractures. We performed a systematic review and meta-analysis of studies comparing the outcomes of vertebroplasty and kyphoplasty, which included prospective non-randomized, retrospective comparative, and randomized studies.

Materials and methods

We searched MEDLINE, EMBASE, and the Web of Science databases for studies of kyphoplasty versus vertebroplasty from 1 January 1990 to 30 November 2014 and compared the following outcomes: procedure characteristics, pain and disability improvement, complications and anatomic outcomes. A subgroup analysis was performed comparing pain outcomes based on the risk of bias.

Results

29 studies enrolling 2838 patients (1384 kyphoplasty and 1454 vertebroplasty) were included. 16 prospective non-randomized studies, 10 retrospective comparative studies, and 3 randomized controlled studies were included. No significant differences were found in mean pain scores between the two groups postoperatively (2.9±1.5 kyphoplasty vs 2.9±1.7 vertebroplasty, p=0.39) and at 12 months (2.7±1.8 kyphoplasty vs 3.2±1.8 vertebroplasty, p=0.64). No significant differences were found in disability postoperatively (34.7±7.1 kyphoplasty group vs 36.3±7.8 vertebroplasty group, p=0.74) or at 12 months (28.3±16 kyphoplasty group vs 29.6±13.9 vertebroplasty group, p=0.70). Kyphoplasty was associated with lower odds of new fractures (p=0.06), less extraosseous cement leakage (p<0.01), and greater reduction in kyphotic angle (p<0.01).

Conclusions

No significant difference was found between vertebroplasty and kyphoplasty in short- and long-term pain and disability outcomes. Further studies are needed to better determine if any particular subgroups of patients would benefit more from vertebroplasty or kyphoplasty in the treatment of vertebral body compression fractures.

Health economic aspects of vertebral augmentation procedures

We reviewed all peer-reviewed papers analysing the cost-effectiveness of vertebroplasty and balloon kyphoplasty for osteoporotic vertebral compression fractures. In general, the procedures appear to be cost effective but are very dependent upon model input details. Better data, rather than new models, are needed to answer outstanding questions. Vertebral augmentation procedures (VAPs), including vertebroplasty (VP) and balloon kyphoplasty (BKP), seek to stabilise fractured vertebral bodies and reduce pain. The aim of this paper is to review current literature on the cost-effectiveness of VAPs as well as to discuss the challenges for economic evaluation in this research area. A systematic literature search was conducted to identify existing published studies on the cost-effectiveness of VAPs in patients with osteoporosis. Only peer-reviewed published articles that fulfilled the criteria of being regarded as full economic evaluations including both morbidity and mortality in the outcome measure in the form of quality-adjusted life years (QALYs) were included. The search identified 949 studies, of which four (0.4 %) were identified as relevant with one study added later. The reviewed studies differed widely in terms of study design, modelling framework and data used, yielding different results and conclusions regarding the cost-effectiveness of VAPs. Three out of five studies indicated in the base case results that VAPs were cost effective compared to non-surgical management (NSM). The five main factors that drove the variations in the cost-effectiveness between the studies were time horizon, quality of life effect of treatment, offset time of the treatment effect, reduced number of bed days associated with VAPs and mortality benefit with treatment. The cost-effectiveness of VAPs is uncertain. In answering the remaining questions, new cost-effectiveness analysis will yield limited benefit. Rather, studies that can reduce the uncertainty in the underlying data, especially regarding the long-term clinical outcomes of VAPs, should be conducted.

The value of routine biopsy during percutaneous kyphoplasty for vertebral compression fractures

Objective

Percutaneous kyphoplasty (PKP) is now widely performed to treat VCF, which is usually caused by osteoporosis. Previous researches have reported unsuspected malignancies found by biopsy. However, the safety and cost-effective profiles of routine biopsy during PKP are unclear. The purpose of this study was to evaluate the feasibility of routine biopsy during PKP in treatment of VCF.

Methods

Ninety-three patients (September 2007–November 2010) undergoing PKP without biopsy were reviewed as the control group. One hundred and three consecutive patients (November 2010–September 2013) undergoing PKP with biopsy of every operated vertebral level were prospectively enrolled as the biopsy group. The rate of unsuspected lesions was reported, and the severe adverse events, surgical duration, cement leakage rate and pain control were compared between the two groups.

Results

No statistically significant differences were found between the two groups, regarding the severe adverse events, surgical duration, cement leakage rate and pain control. Four unsuspected lesions were found in the biopsy group, three of which were malignancies with a 2.9% (3/103) unsuspected malignancy rate. The economic analysis showed that routine biopsy was cost-effective in finding new malignancies comparing with a routine cancer screening campaign.

Conclusions

Routine biopsy during PKP was safe and cost-effective in finding unsuspected malignancies. We advocate routine biopsy in every operated vertebral level during PKP for VCF patients.

A randomized trial comparing balloon kyphoplasty and vertebroplasty for vertebral compression fractures due to osteoporosis

BACKGROUND AND PURPOSE

Several trials have compared vertebral augmentation with nonsurgical treatment for vertebral compression fractures. This trial compares the efficacy and safety of balloon kyphoplasty and vertebroplasty.

MATERIALS AND METHODS

Patients with osteoporosis with 1-3 acute fractures (T5-L5) were randomized and treated with kyphoplasty (n = 191) or vertebroplasty (n = 190) and were not blinded to the treatment assignment. Twelve- and 24-month subsequent radiographic fracture incidence was the primary end point. Due to low enrollment and early withdrawals, the study was terminated with 404/1234 (32.7%) patients enrolled.

RESULTS

The average age of patients was 75.6 years (77.4% female). Mean procedure duration was longer for kyphoplasty (40.0 versus 31.8 minutes, P < .001). At 12 months, 7.8% fewer patients with kyphoplasty (50/140 versus 57/131) had subsequent radiographic fracture, and there were 8.6% fewer at 24 months (54/110 versus 64/111). The results were not statistically significant (P > .21). When we used time to event for new clinical fractures, kyphoplasty approached statistical significance in longer fracture-free survival (Wilcoxon, P = .0596). Similar pain and function improvements were observed. CT demonstrated lower cement extravasation for kyphoplasty (157/214 versus 164/201 levels treated, P = .047). For kyphoplasty versus vertebroplasty, common adverse events within 30 postoperative days were procedural pain (12/191, 9/190), back pain (14/191, 28/190), and new vertebral fractures (9/191, 17/190); similar 2-year occurrence of device-related cement embolism (1/191, 1/190), procedural pain (3/191, 3/190), back pain (2/191, 3/190), and new vertebral fracture (2/191, 2/190) was observed.

CONCLUSIONS

Kyphoplasty and vertebroplasty had similar long-term improvement in pain and disability with similar safety profiles and few device-related complications. Procedure duration was shorter with vertebroplasty. Kyphoplasty had fewer cement leakages and a trend toward longer fracture-free survival.

A randomized trial of balloon kyphoplasty and nonsurgical management for treating acute vertebral compression fractures: vertebral body kyphosis correction and surgical parameters

STUDY DESIGN

Multicenter randomized controlled trial.

OBJECTIVE

To compare the efficacy and safety of balloon kyphoplasty (BKP) with nonsurgical management (NSM) during 24 months in patients with painful vertebral compression fractures (VCFs).

SUMMARY OF BACKGROUND DATA

Recently, several large randomized controlled trials have been conducted and reported how vertebral augmentation compares with NSM for patients with acute VCFs. Few of these trials report on the surgical aspects and radiographical vertebral deformity results.

METHODS

Adults with 1 to 3 VCFs were randomized within 3 months of pain to undergo bilateral BKP (n = 149) or NSM (n = 151). Surgical parameters, subjective quality of life assessments and objective functional (timed up and go) and radiographical assessments were collected.

RESULTS

Compared with NSM, the BKP group had greater improvements in SF-36 physical component summary (PCS) scores at 1 month (5.35 points; 95% CI, 3.41-7.30; P < 0.0001) and when averaged across the 24 months (overall treatment effect 2.71 points; 95% CI, 1.34-4.09; P = 0.0001). The kyphoplasty group also had greater functionality by assessing timed up and go (overall treatment effect -2.49 s; 95% CI, -0.82 to -4.15; P = 0.0036). At 24 months, the change in index fracture kyphotic angulation was statistically significantly improved in the kyphoplasty group (average 3.13° of correction for kyphoplasty compared with 0.82° in the control, P = 0.003). Number of baseline prevalent fractures (P = 0.0003) and treatment assignment (P = 0.004) are the most predictive variables for PCS improvement; however, in patients who underwent BKP, there may also be a link with kyphotic angulation. In BKP, the highest quart for kyphotic angulation correction had higher PCS improvement (13.4 points) than the quart having lowest correction of angulation (7.40 points, P = 0.0146 for difference). The most common adverse events temporally related to surgery (i.e., within 30 d) were back pain (20 BKP, 11 NSM) new VCF (11 BKP, 7 NSM), nausea/vomiting (12 BKP, 4 NSM), and urinary tract infection (10 BKP, 3 NSM). Several other adverse events were possibly related to patient positioning in the operating room.

CONCLUSION

Compared with NSM, BKP improves patient quality of life and pain averaged during 24 months and results in better improvement of index vertebral body kyphotic angulation. Perioperative complications may be reduced with more care in patient positioning.

LEVEL OF EVIDENCE

2.