Vertebral Augmentation Procedures Research Articles

Compressive fatigue properties of a commercially available acrylic bone cement for vertebroplasty

Acrylic bone cements are widely used for fixation of joint prostheses as well as for vertebral body augmentation procedures of vertebroplasty and balloon kyphoplasty, with the cement zone(s) being subjected to repeated mechanical loading in each of these applications. Although, in vertebroplasty and balloon kyphoplasty, the cement zone is exposed to mainly cyclical compressive load, the compressive fatigue properties of acrylic bone cements used in these procedures are yet to be determined. The purposes of the present study were to determine the compressive fatigue properties of a commercially available cement brand used in vertebroplasty, including the effect of frequency on these properties; to identify the cement failure modes under compressive cyclical load; and to introduce a screening method that may be used to shorten the lengthy character of the standardized fatigue tests. Osteopal[Formula: see text] was used as the model cement in this study. The combinations of maximum stress and frequency used were 50.0, 55.0, 60.0, 62.5 and 75.5 MPa at 2Hz; and of 40.0, 55.0, 60.0, 62.5 or 75.5MPa at 10Hz. Through analysis of nominal strain-number of loading cycles results, three cement failure modes were identified. The estimated mean fatigue limit at 2Hz (55.4MPa) was significantly higher than that at 10Hz (41.1MPa). The estimated fatigue limit at 2Hz is much higher than stresses commonly found in the spine and also higher than that for other acrylic bone cements tested in a full tension-compression fatigue test, which indicates that tension-compression fatigue testing may substantially underestimate the performance of cements intended for vertebroplasty. A screening method was introduced which may be used to shorten the time spent in performing compressive fatigue tests on specimens of acrylic bone cement for use in vertebral body augmentation procedures.

Vertebral augmentation: report of the Standards and Guidelines Committee of the Society of NeuroInterventional Surgery

Vertebroplasty and kyphoplasty are minimally invasive image-guided procedures that involve the injection of cement (typically polymethylmethacrylate (PMMA)) into a vertebral body. Kyphoplasty involves inflation of a balloon tamp to create...

Vertebroplasty and kyphoplasty: national outcomes and trends in utilization from 2005 through 2010

Background contextVertebral compression fractures secondary to low bone mass are responsible for almost 130,000 inpatient admissions and 133,500 emergency department visits annually, totaling over $5 billion of direct inpatient costs. Although most vertebral compression fractures heal within a few months with conservative therapy, a significant portion fail to improve with conservative treatment and require long-term care, conservative treatment, or both. Fractures that fail conservative therapy are treated with vertebral augmentation procedures (VAPs) such as vertebroplasty (VP) and kyphoplasty (KP). Two large randomized clinical trials published in 2009 questioned the efficacy of VP in treatment of VAPs. PurposeThis study aimed to investigate trends in utilization of VP and KP between 2005 and 2010 to capture the impact of the 2009 literature on utilization of VAPs. The study also compares patient characteristics and perioperative outcomes between VP and KP to further delineate the risks of each procedure. Study designRetrospective analysis of national utilization rates, clinical outcomes, patient demographics, and patient comorbidities using a large national inpatient database. Patient sampleA total of 63,459 inpatient admissions from 46 states and more than 1,000 different hospitals were included in the analysis. Outcome measuresLength of stay (LOS), total direct cost, mortality, postoperative complications. MethodsData were obtained from the National Inpatient Sample database for the period between 2005 and 2010. National Inpatient Sample is the largest publicly available all payer inpatient database in the United States. Patients undergoing VP and KP were identified via corresponding the International Classification of Diseases, 9th Revision procedure codes. National utilization trends were estimated using weights supplied as part of the National Inpatient Sample dataset. Information on patient comorbidities and demographics was collected. A series of univariate and multivarariate analyses were used to identify statistically significant differences in patient characteristics, clinical outcomes, as well as cost and LOS between patients undergoing VP versus KP. ResultsA total of 307,050 inpatient VAPs were performed in the United States between 2005 and 2010. Of those procedures, 225,259 were KP and 81,790 were VP. Kyphoplasty utilization showed an increasing trend between 2005 and 2007, increasing from 27 to 33 procedures per 100,000 capita older than 40 years. During the same time period, VP utilization remained constant at approximately nine procedures per 100,000 capita older than 40 years. After 2007, utilization of both VP and KP decreased. The most precipitous decrease in VAP utilization occurred in 2009. Patients undergoing VP were on average older (76.7 vs. 77.8, p<.0001), more frequently women (74.48% vs. 73.15%, p=.00083), and black (1.77% vs. 1.55%, p=.004059). Patients undergoing VP had on average more comorbidities then those undergoing KP. Patients undergoing VP had a higher rate of postoperative anemia secondary to acute bleeding and higher rate of venous thromboembolic events. Those undergoing KP had a greater rate of cardiac complications; however, this difference was not statistically significant when taking into account patient age and comorbidity burden. Vertebroplasty was associated with higher mortality (0.93% vs. 0.60%, p<.001), longer LOS (6.78 vs. 5.05 days, p<.0001), and lower total cost ($42,154 vs. $46,101, p<.0001). ConclusionsOverall, KP was associated with lower complication rates, shorter LOS, and a higher total direct cost compared with VP. Utilization rates showed a significant decrease since 2009 in both VP and KP, suggesting that both procedures were impacted by the two randomized controlled trials published in 2009 that suggested poor efficacy of VP.

Impact of Nonoperative Treatment, Vertebroplasty, and Kyphoplasty on Survival and Morbidity After Vertebral Compression Fracture in the Medicare Population

The treatment of vertebral compression fractures with vertebral augmentation procedures is associated with acute pain relief and improved mobility, but direct comparisons of treatments are limited. Our goal was to compare the survival rates, complications, lengths of hospital stay, hospital charges, discharge locations, readmissions, and repeat procedures for Medicare patients with new vertebral compression fractures that had been acutely treated with vertebroplasty, kyphoplasty, or nonoperative modalities. The 2006 Medicare Provider Analysis and Review File database was used to identify 72,693 patients with a vertebral compression fracture. Patients with a previous vertebral compression fracture, those who had had a vertebral augmentation procedure in the previous year, those with a diagnosis of malignant neoplasm, and those who had died were excluded, leaving 68,752 patients. The patients were stratified into nonoperative treatment (55.6%), vertebroplasty (11.2%), and kyphoplasty (33.2%) cohorts. Survival rates were compared with use of Kaplan-Meier analysis and Cox regression. Results were adjusted for potential confounding variables. Secondary parameters of interest were analyzed with the chi-square test (categorical variables) and one-way analysis of variance (continuous variables), with the level of significance set at p &lt; 0.05. The estimated three-year survival rates were 42.3%, 49.7%, and 59.9% for the nonoperative treatment, vertebroplasty, and kyphoplasty groups, respectively. The adjusted risk of death was 20.0% lower for the kyphoplasty group than for the vertebroplasty group (hazard ratio = 0.80, 95% confidence interval, 0.77 to 0.84). Patients in the kyphoplasty group had the shortest hospital stay and the highest hospital charges and were the least likely to have had pneumonia and decubitus ulcers during the index hospitalization and at six months postoperatively. However, kyphoplasty was more likely to result in a subsequent augmentation procedure than was vertebroplasty (9.41% compared with 7.89%; p &lt; 0.001). Vertebral augmentation procedures appear to be associated with longer patient survival than nonoperative treatment does. Kyphoplasty tends to have a more striking association with survival than vertebroplasty does, but it is costly and may have a higher rate of subsequent vertebral compression fracture. These provocative findings may reflect selection bias and should be addressed in a prospective, direct comparison of methods to treat vertebral compression fractures. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison Between Radiofrequency Targeted Vertebral Augmentation and Balloon Kyphoplasty in the Treatment of Vertebral Compression Fractures: Addressing Factors that Affect Cement Extravasation and Distribution

Background: Both vertebroplasty and balloon kyphoplasty have been described for treatment of vertebral compression fractures. Vertebroplasty is known for its high leakage rate compared with balloon kyphoplasty. In vitro studies have shown that high-viscosity cements significantly decrease the incidence of cement leakage and increase the predictability of cement fill in cancellous bonelike substrates compared with low-viscosity cements. Objective: This study compares the incidence and pattern of cement leakage in cases treated with standard balloon kyphoplasty (BKP) and a novel vertebral augmentation procedure, radiofrequency targeted vertebral augmentation (RF-TVA). Study Design: Retrospective evaluation of postoperative radiographs. Setting: Single center inpatient and outpatient population. Methods: Two methods of vertebral augmentation were utilized. Conventional bipedicular BKP and RF-TVA, a novel unipedicular technique which uses a navigational osteotome to create targeted, bone sparing cavities and RF energy to deliver an ultra-high viscosity cement at a consistent rate via a remote controlled, automated hydraulic delivery system. Postoperative radiographs of patients treated with the 2 techniques were critically analyzed for the incidence and location of cement leakage. Eighty consecutive patients with 106 treated levels were included. Thirty-five patients with 49 levels in the BKP and 45 patients with 57 levels in RF-TVA group were evaluated. Results: Leakages less than 1-2 mm were not reported since they may not represent any clinical significance. In the BKP group, 6 leakages (12%) were reported (3 discal, 2 venous, one paravaertebral, and no epidural). In the RF-TVA group, a total of 3 leakages (5%) were reported, (one discal, 2 venous, no paravaertebral or epidural). Using contingency analysis for leakage per level, there was a statistical difference for leakage between RF-TVA and standard BKP, P &lt; 0.01. Limitations: Retrospective study, single center. Conclusions: The RF-TVA technique may provide an approximately 50% reduction in leakage rate when compared to standard BKP. This may be related to the combination of controlled delivery of radiofrequency activated (high viscosity) cement at a fixed, low rate of delivery into sitespecific channels created using a navigational osteotome. Additionally, based on the unipedicular access and remotely controlled cement delivery RF-TVA may decrease procedural invasiveness and physician radiation exposure, respectively. Institutional Review: This study was approved by the Institutional Review Board. Key words: Balloon kyphoplasty, radiofrequency targeted vertebral augmentation, compression fractures, cement leakage

Vertebroplasty Augmentation Procedures: Examining the Controversy

Background: Vertebral compression fractures are a common pathology affecting primarily the elderly, postmenopausal women, and those with metastatic vertebral disease. Vertebral augmentation procedures are popular treatment options for stability and pain relief. Preliminary studies have suggested that such procedures are adequately efficacious. However, the first randomized controlled trials (RCTs) published in the New England Journal of Medicine in 2009 showed that these procedures were not significantly different than placebo with regards to pain relief and quality of life. These studies were met with considerable criticism. The matter was further complicated when The Lancet published an RCT of its own that demonstrated the superiority of vertebroplasty over conservative management. The conflicting evidence has sparked ongoing debate in the medical community. All sides have provided arguments supported by evidence of varying strength and validity. Objective: To provide a concise and comprehensive presentation of the controversy surrounding vertebral augmentation procedures and the evidence cited by proponents on both sides of the debate. Methods: We began by researching the major randomized controlled trials both for and against vertebroplasty. These articles were already known to us, and were used as a starting point. We then performed a literature search in PubMed for articles dated from 2000 through 2012. The bibliographies of major articles and reviews were also cross-referenced for additional sources. Results: A number of articles that included comprehensive and systematic reviews, metaanalyses, and commentaries about noted studies were found. These provided a broad, detailed overview of the subject. Many of the common themes of these articles included limitations in the design, methods, and patient selection with regard to the RCTs and other available studies. Limitations: This review does not analyze the quality of evidence available nor does it provide an opinion in this regard. The conclusions of the present article are, therefore, general and descriptive in nature. Conclusions: The arguments presented by proponents of both sides of the debate appear to have validity. All of the major studies cited as evidence for or against vertebral augmentation procedures have limitations in their quality. Consequently, the debate cannot be concluded, convincingly, until more elaborate studies are conducted involving larger numbers of patients with clear procedure methods agreed upon by the major authorities in the field. Key words: Vertebroplasty, kyphoplasty, vertebral augmentation procedures, controversy of vertebroplasty, vertebral cancer, vertebral pain, compression fractures, back pain, vertebral fractures.

Vertebroplasty and Kyphoplasty: National Outcomes and Trends in Utilization from 2005 Through 2010

Vertebral compression fractures (VCFs) secondary to low bone mass are responsible for almost 130,000 inpatient admissions and 133,500 emergency department visits annually, totaling over $5 billion of direct inpatient costs. Although most VCFs heal within a few months with conservative therapy, a significant portion fail to improve with conservative treatment and require long-term care, conservative treatment or both. Fractures that fail conservative therapy are treated with vertebral augmentation procedures such as vertebroplasty (VP) and kyphoplasty (KP). Two large randomized clinical trials published in 2009 questioned the efficacy of VP in treatment of VAPs.

Cement volume is the most important modifiable predictor for pain relief in BKP: results from SWISSspine, a nationwide registry

The effectiveness of vertebral augmentation techniques is a currently highly debated issue. The biomechanical literature suggests that cement filling volumes may play an important role in the "dosage" of vertebral augmentation and its pain alleviating effect. Good clinical data about filling volumes are scarce and most patient series are small. Therefore, we investigated the predictors of pain alleviation after balloon kyphoplasty in the nationwide SWISSspine registry where cement volumes are also recorded. All single-level vertebral fractures with no additional fracture stabilization and availability of at least one follow-up within 6 months after surgery were included. The following potential predictors were assessed in a multivariate logistic regression model with the group's average pain alleviation of 41 points on VAS as the desired outcome: patient age, patient sex, diagnosis, preoperative pain, level of fracture, type of fracture, age of fracture, segmental kyphotic deformity, cement volume, vertebral body filling volume, and cement extrusions. There were 194 female and 82 males with an average age of 70.4 and 65.3 years, respectively. Female patients were about twice as likely for achieving the average pain relief compared to males (p = 0.04). The preoperative pain level was the strongest predictor in that the likelihood for achieving an at least 41-point pain relief increased by about 8 % with each additional point of preoperative pain (p < 0.001). A thoraco-lumbar fracture had a three times higher odds for the average pain relief compared with a lumbar fracture (p = 0.03). An A.3.1 fracture only had about a third of the probability for average pain relief compared with an A.1.1 fracture (p = 0.004). Cement volumes up to 4.5 ml only had an approximately 40 % chance for a minimum 41-point pain alleviation as compared with cement volumes of at least 4.5 ml (p = 0.007). In addition, the relationship between cement volume and pain alleviation followed a dose-dependent pattern. Cement volume was revealed as a significant predictor for pain relief in BKP. Cement volume was the third most important influential covariate and the most important modifiable and operator dependent one. The clear dose-outcome relationship between cement filling volumes and pain relief additionally supports these findings. Cement volumes of >4.5 ml seem to be recommendable for achieving relevant pain alleviation. Patient sex and fracture type and location were further significant predictors and all these covariates should be recorded and reported in future studies about the pain alleviating effectiveness of vertebral augmentation procedures.

Neurological deficit due to cement extravasation following a vertebral augmentation procedure

The authors endeavor to highlight the surgical management of severe neurological deficit resulting from cement leakage after percutaneous vertebroplasty and to systematically review the literature on the management of this complication. A patient presented after a vertebroplasty procedure for traumatic injury. A CT scan showed polymethylmethacrylate leakage into the right foramina at T-11 and L-1 and associated central stenosis at L-1. He underwent decompression and fusion for removal of cement and stabilization of the fracture segment. In the authors' systematic review, they searched Medline, Scopus, and Cochrane databases to determine the overall number of reported cases of neurological deficit after cement leakage, and they collected data on symptom onset, clinical presentation, surgical management, and outcome. After surgery, despite neurological recovery postoperatively, the patient developed pneumonia and died 16 days after surgery. The literature review showed 21 cases of cement extravasation with neurological deficit. Ultimately, 15 patients had resolution of the postoperative deficit, 5 had limited change in neurological status, and 2 had no improvement. Cement augmentation procedures are relatively safe, but certain precautions should be taken to avoid such complications including high-resolution biplanar fluoroscopy, considering the use of a local anesthetic, and controlling the location of cement spread in relationship to the posterior vertebral body. Immediate surgical intervention with removal of cement provides good results with complete recovery in most cases.

A Cadaver Study to Compare Vertebral Augmentation With a High-viscosity Cement to Augmentation With Conventional Lower-viscosity Cement

Comparison of extravasations in fractured cadaver vertebrae augmented with commercial low-viscosity versus high-viscosity cements. Use of high-resolution, 3-dimensional (3D) imaging to test the hypothesis that high-viscosity cements can reduce the type and severity of extravasations after vertebral augmentation procedures. Cement extravasations are one of the primary complications of vertebral augmentation procedures. There is some evidence that high-viscosity cements might reduce extravasations, but additional data are needed to confirm the early findings. A range of vertebral fractures were created in fresh human cadavers. One group was then augmented with a low-viscosity polymethylmethacrylate (PMMA)-based cement and the other group injected with high-viscosity PMMA-based cement. High-resolution computerized tomography exams were obtained, and extravasations were assessed using 3D volume renderings. The type and severity of extravasations were recorded and analyzed. The proportion of vertebrae with any type of extravasation through the posterior wall to the spinal canal, into small vessels laterally or anteriorly, through the endplates, or anywhere around the body was not significantly different between the high-viscosity and low-viscosity groups. There was significantly less severe extravasation through the endplates (P=0.02), and a trend toward less severe extravasation through vessels (P=0.06) with the high versus low-viscosity cements. In agreement with previous research, high-viscosity PMMA-based cement may help to reduce the more severe forms of extravasations after vertebral augmentation procedures in newly fractured vertebrae.

Kyphoplasty versus vertebroplasty for treatment of osteoporotic vertebral compression fractures

Background The incidence of osteoporotic vertebral compression fractures increases with advancing age and is associated with significant healthcare expenditure. Patients who have sustained fractures from osteoporosis are at increased risk of additional fractures because of loss of bone strength caused by osteoporosis. Vertebroplasty is a minimally invasive vertebral augmentation procedure to relieve pain; it stabilizes the vertebral body. Kyphoplasty is a minimally invasive method for correction and augmentation of osteoporotic vertebral fractures. Materials and methods This study included two groups of patients suffering from painful osteoporotic vertebral compression fractures: the first group comprised 26 patients with 33 vertebral compression fractures treated by percutaneous vertebroplasty between April 2007 and October 2008. The results of this group were compared with those of another group of 18 patients (24 vertebrae) who were treated by kyphoplasty between November 2008 and July 2011. The visual analog scale (VAS) and the Oswestry Disability Index (ODI) were applied for the assessment of patients preoperatively and postoperatively. Results In the vertebroplasty group, the mean VAS score improved from 7.8 to 2.4 according to VAS and from 69 to 15 according to ODI. Cement leakage was noted in four patients (15.4%), without clinical consequence. Ten vertebrae (30.3%) revealed a mean improvement in vertebral height of 11% (8–14%). No patient showed progression of vertebral angles of the augmented vertebrae during the follow-up period. In the kyphoplasty group, the mean pain score improved from 8 to 2.1 according to VAS and from 71 to 17 according to ODI. Cement leakage was noted in two patients (11.11%), without clinical consequence. No thoracolumbar back pain was reported after kyphoplasty. Nineteen vertebrae (79.16%) revealed a mean improvement in vertebral height of 22% (range, 18–38%). No patient showed progression of vertebral angles of the augmented vertebrae during the follow-up period. Conclusion Both vertebroplasty and kyphoplasty resulted in significant improvement in VAS pain scores. Vertebroplasty, although less expensive than kyphoplasty, had a statistically greater risk for cement leakage and adjacent vertebral fracture.

Balloon Kyphoplasty Versus KIVA Vertebral Augmentation—Comparison of 2 Techniques for Osteoporotic Vertebral Body Fractures

Prospective, parallel-group, controlled comparative randomized study. This study compares the efficacy in sagittal vertebral height and wedge deformity restoration, polymethylmethacrylate cement leakage safety, and functional outcome of balloon kyphoplasty (BK) versus KIVA (a novel vertebral augmentation technique) implant for the augmentation of fresh osteoporotic vertebral body fractures. Minimally invasive vertebral augmentation procedures have been widely used to treat vertebral compression fractures caused by osteoporosis. The results of these trials are encouraging in augmenting the vertebra and reducing the wedge deformity. However, after BK, polymethylmethacrylate leakage remains common after A3.1 AO type fractures, with a frequency per vertebra into the epidural space up to 9.8% but less common (0.03%-5.6%) in A1.1 AO type fracture. KIVA is a novel percutaneous uniportal vertebral augmentation device that is designed to restore the vertebral body and reduce polymethylmethacrylate leakage. From a total 190 patients with osteoporotic fractures who were initially enrolled in this prospective randomized study, 10 patients were excluded (5 met exclusion criteria, 5 with evidence of metastasis). This study examined 82 patients (69 ± 11 yr) with 133 fractures who received KIVA and 86 patients (72 ± 9 yr) with 122 fractures that were reinforced with BK. Anterior (anterior vertebral body height ratio [AVBHr]), midline (midline vertebral body height ratio [MVBHr]), and posterior (posterior vertebral body height ratio [PVBHr]) vertebral body height ratio and Gardner segmental vertebral wedge deformity were measured preoperatively to postoperatively. New fractures were recorded at the final observation. The baseline anthropometric and roentgenographic parameters did not differ between the 2 groups. Any cement leakage was examined on plain roentgenograms and computed tomographic scan. All patients were followed for an average of 14 months (range, 13-15 mo) postoperatively. RESULTS.: At the final observation, both KIVA and BK restored significantly AVBHr, PVBHr, and MVBHr. However, only KIVA device reduced significantly the Gardner angle (P = 0.002). Residual kyphosis of more than 5° was measured significantly more (P < 0.001) in the BK than in KIVA spines. KIVA showed significantly lower (3%, χ2, P ≤ 0.05) leakage) [corrected] (paravertebral, intradiscal) rate per vertebra than BK (0.098%) in which because of intracanal leakage 2 patients developed acute paraplegia and were reoperated in emergency. New fracture rate was similar in both groups. Back pain scores (visual analogue scale), 36-Item Short Form Health Survey (Physical Function and Mental Health domains), and Oswestry Disability Index scores improved significantly in the patients of both groups. Both KIVA and BK restored in short-term similarly vertebral body height, but only KIVA restored vertebral body wedge deformity. KIVA was followed by significantly lower and harmless always extracanal leakage rate than BK. Longer observation is needed to show whether these radiological changes have any functional impact.

Wireless Connection between Guide Wires and Bone Cement: Extravasated Methyl Methacrylate Mimicking a Retained Guide Wire

We present the case of a 56-year-old double lung transplant recipient with chest pain who underwent an attempted endovascular retrieval of what was described as a retained guide wire in the azygos vein. After successfully grasping the tip, the object further migrated to the right pulmonary artery complicating the retrieval. It was realized that the “wire” was extravasated methyl methacrylate from a recent percutaneous kyphoplasty. This is believed to be the first report of attempted endovascular retrieval of extravasated methyl methacrylate in the azygos system. We include the details of this case and briefly review the current literature on the management of extravasated methyl methacrylate from vertebral augmentation procedures. Extravasated methyl methacrylate in the venous system is a common finding after vertebral augmentation procedures and any radiopaque stripe arising from a cemented vertebral body should be first described as probable cement leakage.

Pulmonary Embolism with Vertebral Augmentation Procedures

With the prevalence of an aging American population on the rise, osteoporotic vertebral fractures are becoming a common occurrence, resulting in an increase in vertebral augmentation procedures and associated complications such as cement leakage, vertebral compressions, and pulmonary embolism. We describe a patient who presented with respiratory distress three years following kyphoplasty of the lumbar vertebra. Computed tomography (CT) angiogram of the chest confirmed the presence of polymethylmethacrylate (PMMA) cement in the lung fields and pulmonary vessels. We conducted a systematic review of the published literature identifying effective management strategies for the treatment of vertebroplasty-associated pulmonary embolism.

Current status of percutaneous vertebroplasty and percutaneous kyphoplasty--a review.

Percutaneous vertebroplasty (PV) and kyphoplasty (PK) are the 2 vertebral augmentation procedures that have emerged as minimally invasive surgical options to treat painful vertebral compression fractures (VCF) during the last 2 decades. VCF may either be osteoporotic or tumor-associated. Two hundred million women are affected by osteoporosis globally. Vertebral fracture may result in acute pain around the fracture site, loss of vertebral height due to vertebral collapse, spinal instability, and kyphotic deformity. The main goal of the PV and PK procedures is to give immediate pain relief to patients and restore the vertebral height lost due to fracture. In percutaneous vertebroplasty, bone cement is injected through a minimal incision into the fractured site. Kyphoplasty involves insertion of a balloon into the fractured site, followed by inflation-deflation to create a cavity into which the filler material is injected, and the balloon is taken out prior to cement injection. This literature review presents a qualitative overview on the current status of vertebral augmentation procedures, especially PV and PK, and compares the efficacy and safety of these 2 procedures. The review consists of a brief history of the development of these 2 techniques, a discussion on the current research on the bone cement, clinical outcome of the 2 procedures, and it also sheds light on ongoing and future research to maximize the efficacy and safety of vertebral augmentation procedures.

Prospective Single-Site Experience with Radiofrequency-Targeted Vertebral Augmentation for Osteoporotic Vertebral Compression Fracture

Vertebral augmentation procedures are widely used to treat osteoporotic vertebral compression fractures (VCFs). We report our initial experience with radiofrequency-targeted vertebral augmentation (RF-TVA) in 20 patients aged 50 to 90 years with single-level, symptomatic osteoporotic VCF between T10 and L5, back pain severity > 4 on a 0 to 10 scale, Oswestry Disability Index ≥ 21%, 20% to 90% vertebral height loss compared to adjacent vertebral body, and fracture age < 6 months. After treatment, patients were followed through hospital discharge and returned for visits after 1 week, 1 month, and 3 months. Back pain severity improved 66% (P < 0.001), from 7.9 (95% CI: 7.1 to 8.6) at pretreatment to 2.7 (95% CI: 1.5 to 4.0) at 3 months. Back function improved 46% (P < 0.001), from 74 (95% CI: 69% to 79%) at pretreatment to 40 (95% CI: 33% to 47%) at 3 months. The percentage of patients regularly consuming pain medication was 70% at pretreatment and only 21% at 3 months. No adverse events related to the device or procedure were reported. RF-TVA reduces back pain severity, improves back function, and reduces pain medication requirements with no observed complications in patients with osteoporotic VCF.

Cement Embolization of a Segmental Artery after Percutaneous Vertebroplasty: A Potentially Catastrophic Vascular Complication

Serious complications related to percutaneous vertebral augmentation procedures, vertebroplasty and kyphoplasty, are rare and most often result from local cement leakage or venous embolization. We describe an adult patient who underwent multi-level, thoracic percutaneous vertebral augmentation procedures for painful osteoporotic compression fractures. The patient's percutaneous vertebroplasty performed at the T9 level was complicated by the asymptomatic, direct embolization of the right T9 segmental artery with penetration of cement into the radicular artery beneath the pedicle. We review the literature regarding the unusual occurrence of direct arterial cement embolization during vertebral augmentation procedures, discuss possible pathomechanisms, and alert clinicians to this potentially catastrophic vascular complication.

Analysis of utilization patterns of vertebroplasty and kyphoplasty in the Medicare population

ObjectiveTo determine the pattern of utilization of vertebral augmentation procedures including vertebroplasty and kyphoplasty of the lumbar and thoracic spine in the Medicare population in the USA.MethodsThis analysis was performed...

Current and emerging treatment strategies for vertebral compression fractures

Current and emerging treatment strategies for vertebral compression fractures Lotfi Hacein-BeyRadiological Associates of Sacramento Medical Group Inc, Sacramento, CA, USABackground: Vertebral compression fractures are most commonly related to osteoporosis or cancer, both of which are on the rise throughout the world. Once a vertebra is fractured, gradual deterioration of quality of life due to crippling pain and spinal instability usually follows. Although a number of traditional management options have been available to promote pain relief and to allow for increased activities, such as bed rest, bracing, pain medications, and light exercise programs, these have limited effectiveness in the majority of patients. Over 20 years ago, percutaneous vertebroplasty, which is a minimally invasive procedure consisting of the injection of polymethylmethacrylate directly into the fractured vertebra, emerged as an effective treatment. Various vertebral augmentation procedures were subsequently designed, all of which aim at eliminating pain, limiting or reversing vertebral collapse, and providing stability to the affected segment of the spine.Objective: This article discusses clinical aspects of vertebral compression fractures, current indications and contraindications and summarizes technical aspects of vertebroplasty, kyphoplasty, lordoplasty, and device-implanting vertebral augmentation procedures. Treatment effectiveness, which is significant despite recent criticism of vertebroplasty and other vertebral augmentation procedures, is also discussed. As economic pressures on health care systems are increasing in all countries, it is expected that the appropriateness, clinical effectiveness, and cost-effectiveness of vertebral augmentation procedures will be increasingly established by outcome analyses.Conclusion: It is important that physicians are familiar with vertebroplasty and other procedures designed to treat vertebral fractures in patients with advanced osteoporosis or cancer. These fractures, which are common and often crippling, had no real effective treatment until the advent of vertebroplasty. The feasibility and effectiveness of vertebral augmentation procedures are high, whereas the complication rates and overall costs are relatively low.Keywords: vertebral fracture, osteoporosis, vertebroplasty, kyphoplasty, vertebral augmentation

Abstract No. 184: Comparative analysis of cement extravasation in radiofrequency targeted vertebral augmentation, balloon kyphoplasty and high viscosity cement vertebroplasty

Targeting and control of cement delivery is the goal of minimally invasive (MI) treatment of vertebral compression fractures (VCF). In vitro studies have shown high-viscosity cements to significantly decrease the incidence of leakage compared with low-viscosity cements. This study compares the incidence and pattern of cement leakage in cases treated with high-viscosity cement vertebroplasty (VP) (DePuy), standard BKP (Medtronic) and Radiofrequency Targeted Vertebral Augmentation (RF-TVA) (StabiliT System, DFine), novel unipedicular vertebral augmentation procedure that combines an ultra-high viscosity cement delivered into targeted site specific cavities. Retrospective analysis of postoperative radiographs of VCF patients treated with the three MI cement augmentation techniques were analyzed for the incidence and location of cement leakage. 112 consecutive patients with 159 treated levels were included in this review; 66 VP levels, 46 BKP levels and 47 RF-TVA levels, ranging from T3 to L5. In the VP group, 33 leakages in 66 levels (50% per level) were observed (17 discal, 11 venous, 4 paravaertebral and 1 epidural). In the BKP group 31 leakages in 46 levels (67% per level) were observed (15 discal, 11 venous, 3 paravaertebral and 2 epidural). In the RF-KP group 16 leakages in 47 levels (34% per level) were observed, (8 discal, 5 venous, 3 paravaertebral and non epidural). All leakages were asymptomatic. These detailed analyses demonstrate targeted cement augmentation using RF-TVA technique may provide up to 50% reduction in leakage rate when compared to VP with high viscosity cement and standard BKP. These results may be related to targeted cement delivery as a result of the unique combination of controlled delivery of radiofrequency activated (ultra- high viscosity) cement at an optimized delivery rate into multiple site specific channels created using a navigational osteotome. Uni-pedicular access and remote controlled cement delivery further decreases procedural invasiveness and physician radiation exposure.