Intradiscal Electrothermal Annuloplasty Research Articles

217. Impact of previous lumbar spine surgery on outcome of lumbar total disc replacement: analysis of prospective five-year follow up study data

BACKGROUND CONTEXT FDA-regulated prospective trials evaluating lumbar total disc replacement (LTDR) have included patients with previous lumbar surgeries. Unitedhealth care, one of the largest insurers in the United States recently issued a positive coverage policy for LTDR that disqualifies patients with previous lumbar surgeries of any kind from treatment with LTDR. However, such patients were included in FDA IDE trials that led to approval of these devices. PURPOSE The purpose of this study was to compare LTDR outcomes in patients with prior lumbar spine surgery to outcomes in those without prior surgery. STUDY DESIGN/SETTING The study was a post hoc analysis of data collected prospectively as part of an FDA-regulated trial with 5-year follow-up. PATIENT SAMPLE The study was based on 376 patients from the activL® IDE study population. All patients were treated for single-level symptomatic degenerative disc disease at L4-L5 or L5-S1 unresponsive to at least 6 months of nonoperative care. OUTCOME MEASURES Clinical outcome measures used in the study included Oswestry Disability Index (ODI), Visual analog scales (VAS) assessing back and leg pain, SF-36, adverse events and reoperations. Radiographic outcome evaluations were based on flexion/extension range of motion (ROM) and translation of the operated segment. METHODS Patients were divided into two groups: prior lumbar surgery (PLS, n=92) and no prior lumbar surgery (NPLS, n=284). PLS patients had undergone one or more of the following procedures: intradiscal electrothermal annuloplasty (IDET) (n=5), percutaneous nucleoplasty (n=4), microdiscectomy (n=81), hemilaminectomy (n=17), laminotomy (n=36) or other (n=1) prior to receiving a LTDR. Patients with prior lumbar fusion were excluded from the IDE study. Baseline characteristics, functional and pain outcomes, serious adverse events and reoperations were statistically compared between the groups preoperatively and postoperatively at 6 weeks, 3 and 6 months and 1, 2, 3, 4 and 5 years. RESULTS Patient baseline demographics were very similar between the two groups. When comparing pre- to postoperative scores, ODI, VAS back pain and leg pain and the SF-36 Physical Component Score improved significantly (p CONCLUSIONS Prior lumbar spine surgery was not related to compromised outcomes among patients undergoing LTDR. There were no statistically significant differences in ODI, SF-36, pain scores or safety rates between PLS and NPLS patients. These results are in line with findings from earlier studies that prior surgery is not a contraindication for LTDR provided that other selection criteria are met. These results do not support the denial by an insurer to give patients and providers the option of receiving LTDR for DDD unresponsive to nonoperative care as described in the FDA approved device usage labeling. FDA DEVICE/DRUG STATUS activL (Approved for this indication), ProDisc-L (Approved for this indication), Charite (Approved for this indication)

Treatment of intervertebral disc degenerative disease using percutaneous nucleotomy–an overview of less invasive procedures

Background : Less invasive treatment methods for intervertebral disc disease and decompression of neural structures as a consequence of contained disc herniation represent an alternative to surgical procedure. Percutaneus nucleotomy uses a percutaneous approach to the intervertebral disc. The article presents the evolution of numerous procedureds in clinical practice. Methods : Percutaneous nucleoplasty is a fluoroscopy-guided procedure which enables controlled and safe entrance into the intervertebral disc. The procedure is performed under strict aseptic conditions, using a local anaesthesia with the patient under analgosedation. Based on the principle of therapeutic intradiscal action, the procedures can be divided into three groups: chemical (chemonucleolysis with chimopapain, alcohol, ozone), mechanical (automated percutaneous lumbar discectomy – APLD, arthroscopic discectomy) and thermical methods (laser, radiofrequency ablation, intradiscal electrothermal annuloplasty – IDET, Coblation®). Results : Percutaneous nucleotomy by the majority of the mentioned procedures results in a therapeutic effect (reduction of pain and decompression of neural structures). Fast recovery represents a major advantage of less invasive treatment. Conclusions : Less invasive method (nucleotomy using different procedures) represents a successful alternative approach to surgical discectomy. Proper patient selection and safe technique are mandatory in order to achieve a good clinical outcome.

Imaging for provocative discography and minimally invasive percutaneous procedures for treatment of discogenic lower back pain

The imaging for diagnostic and minimally invasive therapeutic procedures for treatment of discogenic pain is comprised mostly of the fluoroscopic real-time imaging. Computed tomography is mainly used following provocative discography to assist in establishing the diagnosis. Intradiscal electrothermal annuloplasty, radiofrequency annuloplasty using DiscTrode™, or transdiscal biacuplasty all utilize fluoroscopy imaging with C-arm features to facilitate the placement of the electrodes. In this review, fluoroscopic imaging for each of these techniques when used for lower back pain, as well as suggested appropriate imaging approaches utilizing minimal radiation exposure are described.

Intradiscal Electrothermal Annuloplasty

Low back pain is a common problem, and although the majority of cases of low back pain resolve, a subset of patients will continue to have intractable pain despite appropriate conservative treatments. Intradiscal electrothermal annuloplasty is a minimally invasive spinal procedure that has been proposed to treat provocation discography-proven internal disk disruption syndrome. The early uncontrolled and nonrandomized intradiscal electrothermal annuloplasty literature suggests it may provide some relief in a small proportion of strictly defined patients; however, more recent randomized, placebo-controlled trials have not substantiated these initial findings. This article will review the published literature, indications, contraindications, safety, and efficacy of the intradiscal electrothermal annuloplasty procedure for the treatment of chronic, intractable, axial back pain.

Pain Medicine and Management: Just the Facts.

Pain Medicine and Management: Just the Facts.

A factor analysis of lumbar intradiscal electrothermal annuloplasty outcomes

Background context Intradiscal electrothermal annuloplasty (IDET) is a minimally invasive procedure for managing chronic discogenic low back pain (LBP). Although there have been numerous reports of IDET outcome rates, few have dissected the detailed factors affecting those outcomes. Purpose To evaluate how heating variables and the number of catheters used affect the outcomes and pain flare-up in LBP patients treated with IDET. Study design/setting Retrospective analysis. Patient sample Data were gathered on the basis of chart records from January 6, 1999 to January 6, 2000. Twenty-five cases treated at a single level with disc protrusion ≤2 mm, nonfocal neurological abnormalities, and positive discogram with annular tear were studied. Six patients were unavailable for follow-up at 16 months. Outcome measures All assessments were incorporated into our own evaluation sheet, completed before the procedure and at follow-up. Assessments included the following: 1) Visual Analog Scale (VAS) and 2) Back Pain Improvement Scales (BPI) preoperatively and at 8 and 16 months post-procedure. Post-procedure flare-up of the pain was defined as the pain aggravation after the IDET procedure from the pre-procedure baseline pain. It was evaluated by a 10-point numeric rating scale, ranging from no aggravated pain “0” to the worst aggravated pain “10”. Methods Patients were partitioned into a single-catheter group and a double-catheter group. In these two groups, statistical analyses were done to compare the outcomes and flare-up duration and intensity. In each catheter group, the correlation coefficients were analyzed between heating variables such as heating duration/temperature and two outcome scales. Then, two outcome scales relative to intensity and duration of post-IDET flare-up were analyzed with Pearson's correlation. Also the combined effect of the heating duration and temperature was evaluated as a thermal dosage, which is the total amount of heat developed during the procedure. It was calculated by multiplying the temperature and its heating duration above a starting temperature of 65°C. Results Comparing the single- and double-catheter groups, patients placed in the single-catheter group showed significantly shorter flare-up duration (11.00±19.17 vs. 24.89±20.84 days, p<.05). In the single-catheter group, the flare-up duration manifested moderate linear correlation with heating variables (0.580 with temperature, 0.519 with thermal dosage, p<.05). Also, the improvements of pain with VAS displayed moderate reverse correlation with heating variables at 8 months (−.436 with temperature, −0.439 with thermal dosage, p<.1). In the double-catheter group, the Back Pain Improvement% had strong reverse correlations with temperature and thermal dosage at 8 months (−.735 and −.729, p<.05). The correlation between the improvement of VAS and temperature yielded a moderate reverse relationship (−.619, p<0.1). These correlations were not, however, observed at 16 months in either the single- or double-catheter groups. Conclusions Higher temperatures and larger total heating doses during IDET procedures with catheters placed in the outer annulus may increase the duration of post-procedure pain flare-ups and lead to less favorable outcomes at 8 months follow-up. The long-term outcomes at 16 months may, however, not be affected by these heating variables.

Atlas of Spine Injection.

Atlas of Spine Injection.

Efficacy of IDET for Relief of Leg Pain Associated with Discogenic Low Back Pain

Intradiscal electrothermal annuloplasty (IDET) is an effective treatment for chronic discogenic low back pain (LBP). However, efficacy of IDET for the treatment of referred leg pain has not been examined. This study was performed to assess the long-term efficacy of IDET for the treatment of referred leg pain in chronic discogenic LBP patients. Data were retrospectively analyzed as an IDET case series from January 1999 to December 2000. The IDET procedure was performed at 1-3 symptomatic levels confirmed by pressure-controlled discography. General pain outcome was evaluated by Visual Analog Scale (VAS). LBP and leg pain were assessed separately using five-point pain scales (subsets of the North American Spine Society [NASS] LBP outcome assessment instrument: 0 = no pain, 4 = worst pain) at the 18-month follow-up. Among 129 patients who underwent IDET, 30 patients underwent subsequent back surgery and were excluded from the study, giving a total of 99 patients. Eighty-three patients (83.8%) had leg pain without sciatica. Fifty-two (52.5%), 21 (21.2%), and 8 (8.0%) patients showed LBP > leg pain, LBP = leg pain and LBP < leg pain, respectively. Fifty-three out of 83 patients (63.9%) showed post-IDET improvement in pain, with a mean VAS score of 3.28 +/- 2.31. Thirty patients (36.1%) showed no improvement. A statistically significant (P < 0.05) improvement in subjective back and referred leg pain was observed. Improvements in back and referred leg pain were well-correlated (r = 0.721, P < 0.01). A relatively large number of LBP patients who underwent IDET (84%) presented with referred leg pain without sciatica. The IDET procedure afforded improvements in leg pain that correlated well with improvements in back pain (0.75/4 and 0.88/4, respectively). These data suggest that IDET may relieve associated limb pain in chronic discogenic LBP patients.

Injection therapies, nerve ablation, and intradiscal electrothermal annuloplasty for degenerative lumbar conditions

Injection therapies, nerve ablation, and intradiscal electrothermal annuloplasty for degenerative lumbar conditions

Disc stimulation and patterns of referred pain.

Prospective, within-subjects, observational experimental design. To determine the pattern of pain response to noxious stimulation of the intervertebral disc. Experimental studies have demonstrated that noxious stimulation of interspinous ligaments, facet joints, and paravertebral muscles causes referred pain into the extremity, with the distal extent of radiation dependent on the intensity of stimulation. Analogous studies have not been performed on the lumbar intervertebral disc. A total of 25 consecutive patients meeting inclusion criteria completed a pain diagram before undergoing the intradiscal electrothermal annuloplasty procedure. The location, intensity, and familiarity of any pain provoked during disc heating were correlated with presenting symptoms and duration of heating. During disc heating, 68% of patients reported exact reproduction of their presenting pain, in both pain quality and location. None of the patients experienced unfamiliar pain during the procedure. The pattern of pain reproduction was consistent; pain originated proximally and progressed distally as stimulus intensity increased. Noxious stimulation of the intervertebral disc may result in low back and referred extremity in patients presenting with these symptoms. The distal extent of pain produced depends on the intensity of stimulation. Disc stimulation may reproduce pain that extends to below the knee.

Intradiscal electrothermal therapy used to manage chronic discogenic low back pain: new directions and interventions.

Retrospective literature review. To review the data on the clinical efficacy of intradiscal electrothermal annuloplasty found at this writing in the peer-reviewed literature to date, to discuss the methodologic strengths and flaws of the studies, to discuss the pitfalls of clinical study designs, to emphasize the need for prospective randomized studies and for increased basic science investigation. Studies published or presented at peer-reviewed societies concerning the clinical efficacy of intradiscal electrothermal annuloplasty are reviewed, including background studies on deafferentation and application of thermal energy to alter biomechanical and structural properties. A proposal for future investigations is presented. Background data from intracapsular annuloplasty highlighting the safety and efficacy of intradiscal electrothermal annuloplasty are presented. Current studies on this procedure, including those in the National Registry are reviewed. All the studies share a common study design: prospective cohort with historical or noninterventional groups used as controls. The patients reviewed are similar. All have nonradicular low back pain of at least 3 months duration, failed conservative care, normal neurologic examination, and MRI showing only nondegenerative disc disease and positive concordant discography. All the patients underwent intradiscal electrothermal annuloplasty lesion at one or two levels according to standard protocols. Follow-up evaluation was performed at various intervals up to 2 years. All the studies used data from a visual analog scale, with most using the Short Form 36 (SF-36) as outcome instruments. The reported follow-up periods for the studies ranged from 6 months to 2 years. Three published studies, one with a 6-month follow-up period and two with a 1-year follow-up period, were published in the peer-reviewed literature. Two recent reports presented to the North American Spine Society were reviewed: a study of patients on a manufacturer-sponsored registry with a 1-year follow-up period and a multicenter prospective cohort study of 75 patients in an intent-to-treat group, with a 1-year follow-up period. Using the 7-point criteria of Deyo et al, all the studies suggested a positive effect of treatment, with a decrease in visual analog scale ratings and improvement in SF-36 scales, particularly those for physical function and bodily pain. The studies published so far suggest that the pain resulting from lumbar disc disease may be diminished by intradiscal electrothermal annuloplasty. All these studies project a positive therapeutic effect. However, all the studies suffer from the same methodologic flaws. A prospective cohort design or a nonrandomized prospective design is used with a biased control. The scientific validity of various study designs is discussed, and a randomized prospective study is recommended. Additionally, more investigation into the basic science of the action of intradiscal electrothermal annuloplasty is required.

New directions and interventions: intradiscal electrothermal annuloplasty to treat chronic discogenic low back pain

Preliminary data on the clinical efficacy of intradiscal electrothermal annuloplasty (IDET) are reviewed, along with the methodologic strengths of studies to date. All studies share a common study design: prospective cohort, with historical or noninterventional groups as controls. Similar patients are reviewed: those with nonradicular low back pain of at least 3 months' duration, failed conservative care, normal neurologic findings, magnetic resonance imaging revealing only nondegenerative disc disease, and positive concordant discography. All patients underwent IDET lesion at one or two levels based on standard protocols. Follow-up was performed at various intervals up to 2 years. All studies used data from the Visual Analogue Scale, with most using the Short Form–36 Health Status Questionnaire as an outcome instrument as well. Three published studies, Saal and Saal (6-month follow-up), Saal and Saal (1-year follow-up), and Karasek and Bogduk (1-year follow-up) were published in the peer-reviewed literature. Two recent reports presented at the North American Spine Society, Thompson and Eckel (1-year follow-up of patients on a manufactured sponsored registry), and the multicenter prospective cohort study of Wetzel et al. (75 patients in the intent-to-treat group, some with 2-year follow-up) are reviewed. All studies suggested a positive effect of treatment with a decrease in Visual Analogue Scale ratings and improvement in Short Form–36 scales, particularly physical function and bodily pain, using the 7-point criteria of Deyo et al. Based on the studies published to date, there is a suggestion that the pain due to lumbar disc disease may be diminished by IDET. All studies to date suggest a positive therapeutic effect. However, all studies suffer from the same methodologic flaws, with a prospective cohort design or a nonrandomized prospective design with a biased control. Additionally, more investigation into the basic science of IDET is required.

Is Intradiscal Electrothermal Annuloplasty (IDET) effective treatment for discogeneic low back pain? A prospective cohort outcome study identifying successful patient selection criteria

Philip Maurer, MD, Dawn Squillante, Philadelphia, PA, USAIntroduction: Chronic discogenic low back pain (LBP) is associated with the breakdown of annular disc collagen resulting in tissues, global disc degeneration, or small disc herniation. Conservative treatments, including physical therapy and medications, are frequently ineffective. Surgical treatments include discectomy and fusion techniques. Intradiscal Electrothermal Annuloplasty (IDET) is a minimally invasive treatment for this difficult problem. IDET delivers thermal energy to the posterior annulus, which has the ability to modify annular collagen and coagulate sensitized nerve tissue. This technology potentially renders a disc asymptomatic, while maintaining normal mechanical function. The purpose of this study is to examine post-IDET outcomes in discogenic LBP patients and offer evidence for patient selection criteria specifically relating to the anatomy of the treated discs.Materials and methods: Seventy-eight consecutive patients underwent IDET and were evaluated through 24 months using Short Form (SF)-36, Visual Analog Scale (VAS) and functional tolerances. Inclusion criteria included relatively normal X-rays, magnetic resonance imaging demonstrating disc pathology with or without small HNP, positive low-pressure discography (less than 50 PSI) and computed tomography discograms demonstrating posterior disruption with integrity of the anterior and lateral annulus. Patients with severe DDD, extruded HNP or previous back surgery were excluded. Catheter navigation was successful in all patients. IDET was standardized (temperature delivery, 90 to 95 C for 17 to 19 minutes). Postoperatively all patients had a corset for 6 weeks and underwent physical rehabilitation. A treatment failure was defined as 2-point improvement in VAS or 10-point increase in either the body pain (BP) or physical function (PF) SF-36 subscales.Results: Patients were followed for 16.9±6.9 months. Sixty percent were male with symptom duration 41 to 44 months. Seventy-two percent of patients were ages 18 to 44 years, and 15.5% were eligible for workmens compensation. Sixty percent had one disc treated, 37% had two discs treated and 3% had three levels treated. No complications were observed (Tables 1 and 2)Table 1OutcomePretreatmentFollow-upChange p ValueSuccess group, 71%VAS6.1±1.81.6±1.44.5±1.9<.0001PF35.6±18.578.2±15.542.3±22.2<.0001BP27.0±16.471.0±18.244.2±25.0<.0001Sitting43.7±42.3100.2±50.556.5±55.9<.0001Standing49.2±44.295.3±54.246.1±51.9<.0001Walking36.2±31.786.5±52.850.3±51.2<.0001Failure group, 29%VAS6.5±1.65.9±2.1−0.6±1.8.2058PF41.9±19.749.1±19.67.5±16.8.0950BP28.6±10.331.6±11.93.0±10.3.2463Sitting34.6±34.139.6±35.77.5±47.4.5576Standing48.9±46.841.6±37.8−6.0±47.5.6190Walking52.6±52.746.1±43.8−6.0±22.2.2963Success versus failure was independent of gender, smoking history, number of discs treated or workmans compensation. In total, 84 discs were identified on discography.Table 2OverallSuccessFailurep ValueStimulating pressure (PSI)31.9±10.331.7±11.433.5±9.1.5210X-ray mild/moderate disc height64.4%65.1%62.5%.9168MRIHIZ17.2%13.0%27.8%.2667Herniation39.1%41.3%33.3%.7763Dark disc54.7%58.7%44.4%.4041CT discogramAnnular fissure59.4%56.5%66.7%.5752Hernation45.3%43.5%50.0%.7812.Conclusion: This study supports the effectiveness of IDET as a safe, minimally invasive procedure for the treatment of discogenic LBP when the strict disc pathology criteria reported in this study is applied. The anatomy treated in this study, stimulating disc pressure, or patient demographics were not found to be related to the incidence of failure. Overall, 71% of patients achieved statistically significant and durable improvement after IDET.

Intradiscal electrothermal annuloplasty: Percutaneous treatment of chronic discogenic low back pain

Intradiscal electrothermal annuloplasty is a procedure that has shown promising results for the treatment of low back pain resulting from internal disc disruption. The best results occur in patients who satisfy the International Association for the Study of Pain criteria for internal disc disruption, which include reproduction of pain on provocation of the target disc but no pain when control discs are stimulated, plus the demonstration of at least a grade 3 annular tear on computed tomographic–discography. The affected disc should retain at least 80% of its normal height, and patients must not have more than 2 discs affected. If these conditions are met, 50% of patients can expect to reduce their pain by half, and 23% can expect complete relief of their pain, with relief being sustained for at least 12 months. Intradiscal electrothermal annuloplasty, however, is an imperfect procedure. There is scope for improving results by close attention to more accurate placement of the electrode. Copyright © 2001 by W.B. Saunders Company

Quantitative annular thermometry in humans and sheep during radiofrequency and electrothermal annuloplasty

Discogenic low back pain is a pervasive, disabling, and costly problem. Internal disc disruption accounts for approximately 40% of all patients who have the chief symptom of axial low back pain. The majority of episodic back pain will resolve without specific treatment. Unfortunately, pain may persist in spite of comprehensive conservative care. Historically, a gulf has existed between the standard conservative treatments of physiotherapy, medication, cognitive therapy, and therapeutic injection and the more aggressive surgical interventions such as fusion. To bridge this gap, percutaneous techniques have been developed to deliver thermal energy to the disc. Heating of the intervertebral disc is hypothesized to decrease nocioception by coagulation of annular nocioceptors, modification of annular collagen, and physiochemical effect on nuclear inflamagens. Success has been reported in clinical trials of intradiscal electrothermal annuloplasty. Single needle intradiscal radiofrequency is clinically ineffective, but a new means of delivering radiofrequency-induced thermal energy to the posterior annulus is now available. Despite clear and increasing interest in percutaneous disc heating, little data is available on in vivo annular thermometry. The thermal dose (temperature × time) required to provide a consistent clinical response is unknown. Thorough knowledge of in vivo annular temperatures achieved with the different heating strategies is necessary to optimize existing technology, safely develop new techniques, and understand mechanisms underlying thermal modulation of discogenic pain. This study reports annular thermometry data obtained in sheep and humans during application of electrothermal conductive and ionic heating to the intervertebral disc. Included are data from the first 4 human intervertebral discs treated with the radiofrequency catheter ionic heating. Copyright © 2001 by W.B. Saunders Company

Thoracic Spine Spasms Secondary to Hemorrhagic Intestinal Ulcer

A case of thoracic spine spasms secondary to a bleeding duodenal ulcer is presented. A 41-year-old male with 14-week history of thoracic spine spasm was treated with bed rest, spinal manipulation, physical therapy, medication, and a thoracolumbar brace. Subsequently, a provocative thoracic discogram performed at T9-T10 created periscapular pain and also reproduced the presenting thoracic spasms. Intradiscal electrothermal annuloplasty (IDET) was performed at the T9-T10 level, but without sustained relief. The patient presented to a spine center for evaluation. The diagnosis of thoracic discogenic disease was suspected. A second provocative thoracic discogram was performed and failed to reproduce his thoracic spasms. Three weeks after being referred to a chronic pain management physician, the patient presented to a local emergency room with hema-temesis. An endoscopic evaluation revealed a bleeding duodenal ulcer. Following medical treatment of the duodenal ulcer with a proton pump inhibitor the patient had complete resolution of his thoracic spasms. This represents the first reported case of thoracic spine spasms as an initial presenting symptom of a bleeding peptic ulcer.

Intradiscal Electrothermal Annuloplasty in Chronic Discogenic Low Back Pain

Chronic discogenic low back pain remains a difficult treatment challenge. Also, Intemal disc derangement in the lumbar spine is a common yet difficult clinical condition to treat. The reported prevalence of chronic low back pain due to intrinsic disc mediated pain is at least 40%. Internal disc derangement has characteristics such as degeneration of the collagen of the disc annulus, fissures, global disc degeneration, and hemiation with or without root compression. The common treatment for chronic discogenic low back pain has been conservative, including physical therapy and pharmacological management but the effectiveness remians controversial. Surgical fusion offers modest results at best, but often fails, and is associated with complications and postoperative continued pain. The intradiscal electrothermal annuloplasty has become known as a safe and effective treatment for patients suffering from discogenic pain and offers the advantage of potentially repairing the damaged disc while maintaining normal disc function. We applied a navigable catheter with a temperature controlled thermal resistive coil, deployed intradiscally through a percutaneous extrapedicular approach under two plane fluoroscopic guidance in chronic low back patients. The authors experienced two cases of chronic discogenic pain that had failed to respond to any kind of conservative treatment but which was successfully relieved by the intradiscal electrothermal annuloplasty. (Korean J Anesthesiol 2001; 40 : 551~556)

Intradiscal Electrothermal Therapy: A Preliminary Report

Internal disc disruption is a common cause of disabling low back pain in a substantial number of young, healthy adults. A clinical diagnosis of internal disruption, in absence of objective clinical findings, is convincingly established only by means of provocation discography. Intradiscal electrothermal therapy has been shown to be effective in managing chronic disabling discogenic pain. This prospective pilot outcome study was designed to investigate the effectiveness of intradiscal electrothermal annuloplasty in a series of patients with chronic functionally disabling discogenic low back pain. The results showed greater than 50% pain relief in 67% of the patients. In addition, a significant decrease in visual analog pain scores was also seen. Further, the assessment of functional status showed significant improvement with standing and walking, whereas sitting also demonstrated significant improvement in 62% of the patients, though it was not statistically significant. No complications were noted in the perioperative period or during the follow-up period. In conclusion, intradiscal electrothermal therapy is a safe and effective procedure in patients suffering with chronic functionally limiting discogenic pain who fail to respond to aggressive conservative modalities of treatments as well as interventional therapy with injections.

Intradiscal Electrothermal Annuloplasty (IDET): A Novel Approach for Treating Chronic Discogenic Back Pain

Objective. This one-year pilot outcome study was designed to investigate prospectively a series of patients with chronic discogenic back pain who underwent intradiscal electrothermal annuloplasty (IDET). Patients with chronic discogenic low back pain usually respond poorly to conservative medical care. Spinal fusion procedures have yielded mixed results. IDET is a new procedure to heat the intervertebral disc for the purpose of relieving discogenic pain. This study presents the one-year results for the first 32 patients undergoing the IDET procedure. The objective of this article is to determine the safety and efficacy of the IDET procedure in patients with chronic discogenic back pain. Methods. Utilizing standard discographic technique, the disc was heated using a navigable intradiscal catheter with a temperature-controlled thermal resistive coil. Six-month and one-year outcomes were assessed comparatively within subjects using a Roland-Morris (RM) questionnaire and a Visual Analog Scale (VAS), and between subjects using the NASS Low Back Pain Outcome Assessment Instrument Satisfaction Index and a general activity scale modified from the back pain/disability scale from the same instrument. The results from the individual outcome measures were combined to generate an overall outcome of favorable, nonfavorable, and no change. Results. There were no significant differences between overall outcome measures at 6-month and 12-month follow-ups. At 12 month follow-up the VAS had a mean decrease of 1.84 (sd = 2.38) and the RM had a mean decrease of 4.03 (sd = 4.82). 78.1% of patients stated that the procedure met their expectations or that they would undergo the same treatment for the same outcome. 53.1% of patients stated that their overall activity level was either better or much better compared to before the procedure. Overall, 62.5% had a favorable outcome, 12.5% nonfavorable, and 25% no change. Patients with excellent or good catheter positions and those with low pressure sensitive discs on preoperative discography had the most favorable outcomes. There were no significant complications. Conclusions. One-year pilot study outcome results suggest that IDET may be an effective, minimally invasive treatment for chronic discogenic low back pain.