Radiofrequency-targeted Vertebral Augmentation Research Articles

Comparison of Radiofrequency-targeted Vertebral Augmentation With Balloon Kyphoplasty for the Treatment of Vertebral Compression Fractures

A retrospective study. The aim of this study was the evaluation of the safety and effectiveness of radiofrequency-targeted vertebral augmentation (RF-TVA) in comparison with balloon kyphoplasty (BK) for the treatment of acute painful vertebral compression fractures (VCFs) on the basis of matched pairs. Vertebroplasty and BK are the common surgical interventions for the treatment of VCF. Both are effective and safe but pose some risks such as adjacent fractures and cement leakage. In 2009, RF-TVA was introduced as an innovative augmentation procedure for the treatment of VCF. A total of 192 patients (116 female; 51-90 y) with VCF (n=303) at 1 to 3 levels were treated with RF-TVA or BK. Functionality (Oswestry Disability Index), pain (visual analogue scale), vertebral height (anterior, middle), and kyphotic angle were evaluated over a 2-year period (postoperatively, 3-4 d, 3, 6, 12, and 24 mo). In addition, operating time and occurrence of cement leakage were recorded. Pain and functionality were significantly improved after both treatments. In both groups, there was an increase in the vertebral height and a decrease in the kyphotic angle, which remained relatively consistent during 24 months. The incidence of cement leakage was 9.4% (n=9) in the RF-TVA group and 24.0% (n=25) in the BK group. The mean operating time with radiofrequency kyphoplasty was 25.9±9.9 minutes, and with balloon kyphoplasty 48.0±18.4 minutes. RF-TVA is a safe and effective procedure for the treatment of vertebral compression fractures when compared with BK. Improvement in pain and functional scores after RF-TVA are durable through 24 months postprocedure and remained better than those after BK at long-term follow-up. Operating time for RF-TVA is shorter and the risk of cement leakage is lower. Both procedures provided similar results in vertebral height restoration and reduction in the kyphotic angle.

Percutaneous Radiofrequency-Targeted Vertebral Augmentation of Unstable Metastatic C2 and C3 Lesions Using a CT-Guided Posterolateral Approach and Ultra–High-Viscosity Cement

Case report. To report the first technical note describing radio frequency-targeted C2 and C3 vertebral augmentation using a posterolateral approach and high-viscosity cement. Percutaneous vertebral augmentation is a minimally invasive procedure used for stabilization and pain control in vertebral compression fractures. Its use in the cervical spine, especially the upper cervical spine, is very limited mainly due to technical challenges. We report the first use of an ultra-high-viscosity cement and posterolateral approach with computed tomography (CT) guidance and computed tomographic fluoroscopy in a patient with lytic lesions in C2 and C3 and a pathologic fracture of C2 for the purpose of stabilization and pain palliation. Technically successful vertebral augmentation of the C2 and C3 vertebral bodies was achieved. There were no complications. The patient reported pain relief and improved range of motion after treatment and the hard cervical collar was removed. Computed tomography-guided radiofrequency-targeted vertebral augmentation of the cervical spine using a posterolateral approach and ultra-high-viscosity cement is a technically feasible procedure that may be used in patients with advanced osteolytic cervical spine metastases who are not surgical candidates for the purpose of pain palliation and fracture stabilization. N/A.

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 < 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

Radiofrequency-Targeted Vertebral Augmentation for the Treatment of Vertebral Compression Fractures as a Result of Multiple Myeloma

A retrospective review of a consecutive population of patients treated with radiofrequency-targeted vertebral augmentation (RF-TVA) for malignant vertebral compression fractures (VCFs). To investigate the safety and efficacy of RF-TVA in patients with malignant VCFs. The use of polymethylmethacrylate (PMMA) in vertebroplasty and balloon kyphoplasty for patients with recalcitrant pain after acute VCFs is shown to be safe, successful in stabilizing the VCF, and effective for the relief of pain after osteoporotic and malignant VCFs. RF-TVA using targeted cavity creation and ultrahigh viscosity PMMA delivery with a long handling time was developed to address the potential adverse issues that arise with vertebroplasty and balloon kyphoplasty. Between December 2008 and May 2009, a consecutive series of 66 RF-TVA procedures were performed by the authors for VCF secondary to multiple myeloma. Pre- and postoperatively, a standard 10-point visual analogue scale was used to assess back pain. Pain medication use and activity categories were defined and monitored for changes before and after RF-TVA. All patients were followed for 6 months postoperatively. At 6 months postoperatively, significant improvement in pain, activity, and narcotic use was observed. There were no pulmonary or neurological complications, and one patient had radiographical evidence of asymptomatic leakage of PMMA into the vertebral disc space. We report optimum safety and efficacy results in the treatment of malignant VCFs with a novel RF-TVA technique in which controlled delivery of an ultrahigh viscosity PMMA is used for fracture stabilization. The deposition of PMMA with RF-TVA is predictable and uniform, and can be performed without the PMMA handling constraints that may be encountered with vertebroplasty and balloon kyphoplasty. The safety and efficacy we report with RF-TVA achieved equivalency with other methods of treatment for VCF stabilization.

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.

Radiofrequency-targeted vertebral augmentation versus traditional balloon kyphoplasty: radiographic and morphologic outcomes of an ex vivo biomechanical pilot study [Erratum

Radiofrequency-targeted vertebral augmentation versus traditional balloon kyphoplasty: radiographic and morphologic outcomes of an ex vivo biomechanical pilot study [Erratum] Erratum Dalton BE, Kohm AC, Miller LE, Block JE, Poser RD. Clinical Interventions in Aging 2012,7:525–531. In the Disclosure section, Dr Andrew C Kohm is referred to as "AWK". This should be "ACK".Read the original article

Abstract No. 183: Radiofrequency targeted vertebral augmentation (RF-TVA) for osteoporotic compression fractures

RF-TVA employs a novel system containing a steerable osteotome for site-specific cavity creation and radiofrequency (RF) modulation of cement viscosity delivered using a hydraulic delivery system. We report a prospective study of patients with acute osteoporotic vertebral compression fractures (VCF) with this system. Between May 2009 and January 2011, 20 patients with 1-3 painful VCFs (confirmed by MRI and pain concordant with index level) who were to receive kyphoplasty treatment were enrolled. Inclusion criteria included age between 50-90, Visual Analogue Pain (VAS) score >4, a moderate (21-40%) or greater Oswestry Disability Index (ODI) score, and 20-90% vertebral compression. VAS and ODI scores were recorded pre-procedure, at discharge, one week, one month, and three months after the procedure. ODI scores were recorded at the same time points except at discharge. Each procedure was performed using this Vertebral Augmentation System. A trocar was placed via a unipedicular approach. . Using a remotely controlled delivery system RF energy was applied tothe PMMA cement as it passed into the delivery cannula. Average patient age was 79.7 ±9.85 years. The mean percentage of collapse was 28 ±13. %. A majority of patients had associated diseases, the most common ones being hypertension (N=14) and coronary artery diseases (N=9). All surgeries were performed within 42 days (av. 13 days) of the patient's reported date of injury. The average procedure time was 18.6 ± 8.95 minutes. No procedure related complications were encountered. No patients required bilateral procedures. The improvement in mean VAS scores from pre-procedure to discharge was 3.4 (p<0.0001). At 1 week, 1 month and 3 months, the improvement in mean VAS score was 3. After three months, the improvement in average ODI scores was significant (34.14%, p < 0.0001). Radiofrequency targeted vertebral augmentation (RF-TVA) is a safe and effective method for treatment of vertebral compression fractures. The use of RF energy, to warm cement immediately prior to entering the patient, results in the unique combination of consistently high viscosity cement useable over an extended working time.

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.

Radiofrequency-targeted vertebral augmentation versus traditional balloon kyphoplasty: radiographic and morphologic outcomes of an ex vivo biomechanical pilot study

PurposeTraditional balloon kyphoplasty (BK) is a common treatment for symptomatic vertebral compression fractures. The purpose of this study was to compare a novel vertebral augmentation technique, radiofrequency-targeted vertebral augmentation (RF-TVA), to BK for restoration of vertebral height, cavity creation, and polymethylmethacrylate (PMMA) delivery and interdigitation into the surrounding trabeculae.MethodsThis ex vivo biomechanical pilot study utilized 16 osteoporotic cadaveric vertebral bodies in a standardized fracture model to compare unipedicular RF-TVA (n = 8) to bipedicular BK (n = 8). Four specimens from each group were tested in loaded and unloaded conditions. All specimens were imaged, assessed for height restoration, and sectioned to observe PMMA distribution. A subset of specimens underwent computed tomography scanning to assess cavity creation and trabecular architecture prior to cement delivery.ResultsAnterior height restoration was greater with RF-TVA (median: 84%, interquartile range: 62%–95%) compared to BK (median: 69%, interquartile range: 60%–81%), although the difference did not achieve statistical significance (P = 0.16). Anterior height restoration was numerically greater under loaded (median: 70% versus 66%) and unloaded (median: 94% versus 77%) conditions with RF-TVA versus BK. RF-TVA produced more discrete cavities and less native trabecular destruction compared to marked trabecular destruction observed with BK. RF-TVA consistently showed a well-identified focal area of PMMA with an extensive peripheral zone of PMMA interdigitation, providing mechanical interlock into the adjacent intact trabecular matrix. In contrast, BK yielded little evidence of PMMA interdigitation beyond the boundaries created by the balloon tamp due to the crushed trabecular bone peripherally.ConclusionRF-TVA achieves favorable vertebral height restoration with targeted PMMA delivery and less trabecular destruction compared to BK. RF-TVA has potential clinical utility in the aging population with painful osteoporotic vertebral fracture.