Radiofrequency lumbar facet denervation: A comparative study of the reproducibility of lesion size after 2 current radiofrequency techniques
ABSTRACT Radiofrequency facet denervation procedures are widely used for the treatment of chronic low-back pain. Currently, both temperature-controlled and voltage-controlled techniques are used. In this combined in vivo and in vitro study, the electrophysiologic consequences and the effects on lesion size of these techniques were determined.
Thirty-three patients were randomly assigned to receive a lumbar radiofrequency facet denervation by using either temperature-controlled (80 degrees C, 60 seconds) or voltage-controlled (20 V, 60 s) mode. Electrophysiologic parameters in both groups during radiofrequency lesioning were registered. Observed differences between electrodes were quantified and interpreted, using lesion-size data from egg-white experiments.
Seventeen patients in the temperature group were treated with a total of 55 radiofrequency lesions, all considered technically adequate. In the voltage-controlled group, 16 patients received 63 lesions. Of these, 44 (69.8%) procedures were found to be technically inadequate. Voltage-controlled radiofrequency lesioning resulted in uncontrollable fluctuations of temperature, with resultant uncontrollable variations in lesion size. Temperature-controlled mode created reproducible lesion sizes.
There is no consistent relation between voltage and the temperature obtained during radiofrequency lumbar facet denervation. Temperature-controlled radiofrequency lesioning is preferred to create reproducible lesion sizes.
[Show abstract] [Hide abstract]
ABSTRACT: Clinical recommendations for the duration of radiofrequency (RF) delivery have been based on no-fluid design, which may not be representative of clinical practice where fluid preinjection occurs. The purpose of this study was to examine the interaction between the preinjection of fluids of differing compositions and duration of RF on lesion size. The variability of lesion development under different preinjection conditions was also examined across the RF lesion duration. Monopolar RF was performed with ex vivo chicken samples for 180 seconds without fluid preinjection or with fluid preinjected. Nonionic and ionic fluids were investigated. Lesion size parameters and and power levels were measured every 10 seconds. The surface area and efficiency index were calculated. The preinjection of specific fluid increased the maximum mean surface area. Lesion growth continued throughout the entire lesion cycle. When all groups were considered together, the largest mean surface area occurred at 180 seconds. The preinjection of specific fluids altered the rate of lesion growth and the time required to achieve maximum lesion size in a fluid-specific manner. Significant variability was documented in the rate and amount of lesion growth under each condition. Extending lesioning time resulted in reduced lesion variability. Fluid preinjection alters both final lesion size and the time required to achieve maximum lesion size. Extending the duration of RF lesion cycle beyond 90 seconds when fluid is preinjected allows for lesion size to be maximized while limiting lesion size variability, both of which assist in successfully lesioning a targeted nerve.
[Show abstract] [Hide abstract]
ABSTRACT: Study Design. A systematic review and meta-analysis of randomized controlled trials.Objective. To assess treatment effects (benefits and harms) of radiofrenquency denervation for patients with facet joint related chronic low back pain.Summary of Background Data. There is no consensus regarding the treatment efficacy of facet joint radiofrequency denervation (FJRD) and how it compares to nerve blockades and joint infiltration with anesthetics and/or corticosteroids.Methods. We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and LILACS for randomized controlled trials (RCTs) that compared FJRD with blockades, infiltrations, or placebo. Primary outcomes were pain, functional status, and quality of life. Secondary outcomes were cost-effectiveness and complications.Results. Fifteen studies were selected and nine were eligible. Overall quality of evidence was rated low to moderate. The evidence favored FJRD regarding pain control. There was no sufficient evidence for cost-effectiveness and complications.Conclusion. The available evidence reviewed in this study should be interpreted with caution. The data indicates that FJDR is more effective than placebo in pain control and functional improvement, and is also possibly more effective than steroid injections in pain control. Complications and adverse effects were not sufficiently reported to allow comparisons, and there was no evidence for cost-effectiveness. High-quality RCTs addressing pain, function, quality of life, complications, and cost-effectiveness are urgently needed.Spine 04/2014; 39(14). DOI:10.1097/BRS.0000000000000337 · 2.45 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: The purpose of the study was to systematically review the historical therapeutics for chronic pain care directed at the dorsal root ganglion (DRG) and to identify future trends and upcoming treatment strategies. A literature search on bibliographic resources, including EMBASE, PubMed Cochrane Database of Systemic Reviews from literature published from 1966 to December 1, 2012 to identify studies and treatments directed at the DRG to treat chronic pain, and was limited to the English language. Case series, case reports, and preclinical work were excluded. Information on emerging technologies and pharmacologics were captured separately, as they did not meet the inclusion criteria. The literature review yielded three current clinical treatment strategies: ganglionectomy, conventional radiofrequency treatment of the dorsal root ganglion, and pulsed radiofrequency treatment of the DRG. Seven studies were identified utilizing ganglionectomy, 14 for conventional radiofrequency, and 16 for pulsed radiofrequency. Electrical stimulation and novel therapeutic delivery strategies have been proposed and are in development. Despite a robust understanding of the DRG and its importance in acute nociception, as well as the development and maintenance of chronic pain, relatively poor evidence exists regarding current therapeutic strategies. Novel therapies like electrical and pharmacologic strategies are on the horizon, and more prospective study is required to better qualify the role of the DRG in chronic pain care.Pain Medicine 06/2013; DOI:10.1111/pme.12171 · 2.24 Impact Factor