Laser Reconstruction of Spinal Discs Experiments and Clinic

Degenerative disease of the intervertebral discs (DDD) is currently a serious problem facing the world community. The surgical methods and conservative therapy used today, unfortunately, do not stop the pathological process, but serve as a palliative method that temporarily relieves pain and improves the patient’s quality of life. Therefore, at present, there is an active search for new methods of treating DDD. Among new techniques of treatment, biological methods, and minimally invasive surgery, including the use of laser radiation, which, depending on the laser parameters, can cause ablative or modifying effects on the disc tissue, have acquired considerable interest. Here, we analyze a new approach to solving the DDD problem: laser tissue modification. This review of publications is focused on the studies of the physicochemical foundations and clinical applications of a new method of laser reconstruction of intervertebral discs. Thermomechanical action of laser radiation modifies tissue and leads to its regeneration as well as to a long-term restoration of disc functions, elimination of pain and the return of patients to normal life.

Image-Guided Percutaneous Treatment of Lumbar Stenosis and Disc Degeneration

Low back pain, radicular leg pain, and lumbar spinal stenosis are the most common of all chronic pain disorders. Discogenic pain is related to distress of annular fibers and tears, whereas spinal stenosis is related to reduction of the spinal canal dimensions and compression of the neural elements; radicular pain is mainly related to disc herniation and is initially managed conservatively. The percutaneous minimally invasive approach in discogenic and radicular pain is designed to reduce the volume of the nucleus pulposus in patients with failure of medical and physical treatment prolonged for at least 6 weeks.

A comprehensive review of the sinuvertebral nerve with clinical applications

The anatomy and clinical significance of the sinuvertebral nerve is a topic of considerable interest among anatomists and clinicians, particularly its role in discogenic pain. It has required decades of research to appreciate its role, but not until recently could these studies be compiled to establish a more complete description of its clinical significance. The sinuvertebral nerve is a recurrent nerve that originates from the ventral ramus, re-entering the spinal canal via the intervertebral foramina to innervate multiple meningeal and non-meningeal structures. Its complex anatomy and relationship to discogenic pain have warranted great interest among clinical anatomists owing to its sympathetic contribution to the lumbar spine. Knowledge of the nerve has been used to design a variety of diagnostic and treatment procedures for chronic discogenic pain. This paper reviews the anatomy and clinical aspects of the sinuvertebral nerve.

Efficacy of transforaminal laser annuloplasty versus intradiscal radiofrequency annuloplasty for discogenic low back pain

Background

Discogenic pain is a common cause of disability and is assumed to be a major cause of nonspecific low back pain. Various treatment methods have been used for the treatment of discogenic pain. This study was conducted to compare the therapeutic success of radiofrequency (an intradiscal procedure) and laser annuloplasty (both an intradiscal and extradiscal procedure).

Methods

This single-center study included 80 patients and followed them for 6 months. Transforaminal laser annuloplasty (TFLA, 37 patients) or intradiscal radiofrequency annuloplasty (IDRA, 43 patients) was performed. The main outcomes included pain scores, determined by the numeric rating scale (NRS), and Oswestry disability index (ODI), at pre-treatment and at post-treatment months 1 and 6.

Results

The patients were grouped according to procedure. In all procedures, NRS and ODI scores were significantly decreased over time. Mean post-treatment pain scores at months 1 and 6 were significantly lower (P < 0.01) in both groups, and between-group differences were not significant. The ODI score was also significantly decreased compared with baseline. Among patients undergoing TFLA, 70.3% (n = 26) reported pain relief (NRS scores < 50% of baseline) at post-treatment 6 months, vs. 58.1% (n = 25) of those undergoing IDRA. There were no statistically significant differences between the groups in ODI reduction of > 40%.

Conclusions

Our results indicate that annuloplasty is a reasonable treatment option for carefully selected patients with lower back and radicular pain of discogenic origin, and TFLA might be superior to IDRA in patients with discogenic low back pain.

Discogenic low back pain: interventional treatment

Low back pain (LBP) is one of the most common causes of disability in the adult population. A significant place in its genesis is occupied by a degenerative-dystrophic diseases of intervertebral discs. The article highlights the classification and mechanism of discogenic pain origin. Various types of interventions aredescribed for this pathology: indications, specificities of carrying out manipulations and therapeutic effects, efficiency and possible complications of procedures.

Intradiscal electrothermal therapy treatment for back pain

The intradiscal electrothermal therapy (IDET) procedure is a minimally invasive technique designed to treat discogenic chronic low back pain. The debate surrounding IDET ranges from the concept of the procedure, the technique and patient selection, to its effectiveness. The procedure provides modest improvement; however, it is considered less invasive and destructive than other modalities of treatments available at the present time, and has lower cost. The effectiveness evidence is limited at the present time, but based on the results of six recently published positive single-arm studies, it appears that patients experienced a perceptible clinical benefit from the IDET procedure. Thus, IDET is recommended in patients with moderate functional impairment, relatively well-maintained disc heights and discogenic pain caused by annular tears or protrusions less than 3-4 mm after the failure of less invasive procedures.

Nonsurgical interventions for low back pain

A variety of nonoperative interventions are available to treat back pain. Careful assessment, discussion, and planning need to be performed to individualize care to each patient. This article discusses good to fair evidence from randomized controlled trials that injection therapy, percutaneous intradiscal radiofrequency thermocoagulation, intradiscal electrothermal therapy, and prolotherapy are not effective. Evidence is poor from randomized controlled trials regarding local injections, Botox, and coblation nucleoplasty; however, with a focused approach, the right treatment can be provided for the right patient. To be more effective in management of back pain, further high-grade randomized controlled trials on efficacy and safety are needed.

Standards of practice: quality assurance guidelines for percutaneous treatments of intervertebral discs

Percutaneous treatments are used in the therapy of small- to medium-sized hernias of intervertebral discs to reduce the intradiscal pressure in the nucleus and theoretically create space for the herniated fragment to implode inward, thus reducing pain and improving mobility and quality of life. These techniques involve the percutaneous removal of the nucleus pulposus by using a variety of chemical, thermal, or mechanical techniques and consist of removal of all or part of nucleus pulposus to induce more rapid healing of the abnormal lumbar disc. These guidelines are written to be used in quality improvement programs for assessing fluoroscopy- and/or computed tomography-guided percutaneous intervertebral disc ablative techniques.

A randomized double-blind controlled trial of intra-annular radiofrequency thermal disc therapy--a 12-month follow-up

The discTRODE probe applies radiofrequency (RF) current, heating the annulus to treat chronic discogenic low back pain. Randomized controlled studies have not been published. We assessed the long-term effect and safety aspects of percutaneous intradiscal radiofrequency thermocoagulation (PIRFT) with the discTRODE probe in a prospective parallel, randomized and gender stratified, double-blind placebo-controlled study. Twenty selected patients with chronic low back pain and a positive one-level pressure-controlled provocation discography were randomized to either intra-annular PIRFT or intra-annular sham treatment. A blinded interim analysis was performed when 20 patients had been followed for six months. The 6-month analysis did not reveal any trend towards overall effect or difference between active and sham treatment for the primary endpoint: change in pain intensity (0-10). The inclusion of patients was therefore discontinued. After 12 months the overall reduction from baseline pain had reached statistical significance, but there was no significant difference between the groups. The functional outcome measures (Oswestry Disability Index, and SF 36 subscales and the relative change in pain) appeared more promising, but did not reach statistical significance when compared with sham treatment. Two actively treated and two sham-treated patients reported increased pain levels, and in both groups a higher number was unemployed after 12 months. The study did not find evidence for a benefit of PIRFT, although it cannot rule out a moderate effect. Considering the high number, reporting increased pain in our study, we would not recommend intra-annular thermal therapy with the discTRODE probe.

Percutaneous laser discectomy guided with stereotactic computer-assisted surgical navigation

BACKGROUND AND OBJECTIVE

Percutaneous laser discectomy at various wavelengths has been used for minimally invasive surgery of herniated intervertebral discs. Using a high-intensity diode laser at 980-nm wavelength, we aimed to improve the safe insertion of the laser trocar with the aid of a stereotactic computer-assisted surgical navigation system.

STUDY DESIGN/MATERIALS AND METHODS

The experiments were performed on ex vivo porcine spines with intact soft tissue. Before laser irradiation, each specimen was imaged by computed tomography (CT) with fiduciary markers. The Digital Imaging and Communications in Medicine (DICOM standard) data sets were retrieved into the GE Healthcare Surgery InstaTRAK3500 Plus computer-assisted surgical navigation platform via the hospital Ethernet using a picture archiving and communication system. A special trocar with quartz waveguide connected to the navigation system was inserted into a total of 12 lumbar discs of two fresh intact porcine specimens. Various laser energies (200-700 J) with different exposure times were delivered. Pre- and post-irradiation magnetic resonance (MR) imaging and postoperative macroscopic and histologic studies were carried out.

RESULTS

A navigation system accuracy of better than 2 mm was achieved. Tracking of the instrument from pre-acquired formatted CT reconstructed images reduced overall radiation exposure by limiting the need for continuous intraoperative C-arm fluoroscopy. The use of surgical navigation by CT images enhanced the precision insertion of the laser trocar. Irradiation with the 980-nm wavelength diode laser resulted in tissue evaporation changes of the intervertebral disc material as demonstrated by comparing pre- and post-irradiation changes of MR images and macro- and microscopic changes of the dissected disc material.

CONCLUSION

This preclinical study demonstrates the clinical utility of a 980-nm diode laser delivered through a fiber-optic waveguide trocar in which precise insertion was enabled by the use of surgical navigation. This in turn decreases the exposure to ionizing radiation during the procedure.

Acute histologic effects and thermal distribution profile of disc biacuplasty using a novel water-cooled bipolar electrode system in an in vivo porcine model

BACKGROUND

Thermal treatment of the lumbar intervertebral disc has been suggested for the treatment of chronic discogenic pain. Disc biacuplasty (D-BAC) is a novel procedure that uses two water-cooled radiofrequency electrodes in a bipolar configuration to heat a large volume of the posterior annulus fibrosus.

METHODS

Seven porcine lumbar discs were treated with D-BAC to assess acute effects on the treated tissue in a "worst-case"in vivo model. Intradiscal and peridiscal temperatures were measured during treatment and histologic analysis was used to assess for evidence of acute thermal injury.

RESULTS

Temperature monitoring at designated safety zones outside the disc demonstrated maintenance of near-physiologic conditions while temperature in the inner posterior annulus reached 65 degrees C. Histologic sections of treated discs demonstrated no evidence of thermal damage to the dorsal root ganglia or spinal nerve roots when compared with controls. Increased coarseness of the fibrillar matrix and loss of cellular detail were noted in the nucleus pulposus of treated discs.

DISCUSSION

Disc biacuplasty, in a porcine model, achieves suitable temperatures to induce thermal transition of collagen and thermoneurolysis while showing no evidence of damage to neural tissue in safety zones surrounding the disc.

Intervertebral disc: anatomy-physiology-pathophysiology-treatment

This review article describes anatomy, physiology, pathophysiology and treatment of intervertebral disc. The intervertebral discs lie between the vertebral bodies, linking them together. The components of the disc are nucleus pulposus, annulus fibrosus and cartilagenous end-plates. The blood supply to the disc is only to the cartilagenous end-plates. The nerve supply is basically through the sinovertebral nerve. Biochemically, the important constituents of the disc are collagen fibers, elastin fibers and aggrecan. As the disc ages, degeneration occurs, osmotic pressure is lost in the nucleus, dehydration occurs, and the disc loses its height. During these changes, nociceptive nuclear material tracks and leaks through the outer rim of the annulus. This is the main source of discogenic pain. While this is occurring, the degenerative disc, having lost its height, effects the structures close by, such as ligamentum flavum, facet joints, and the shape of the neural foramina. This is the main cause of spinal stenosis and radicular pain due to the disc degeneration in the aged populations. Diagnosis is done by a strict protocol and treatment options are described in this review. The rationale for new therapies are to substitute the biochemical constituents, or augment nucleus pulposus or regenerate cartilaginous end-plate or finally artificial disc implantation..

Evidence-informed management of chronic low back pain with intradiscal electrothermal therapy

The management of chronic low back pain (CLBP) has proven very challenging in North America, as evidenced by its mounting socioeconomic burden. Choosing among available nonsurgical therapies can be overwhelming for many stakeholders, including patients, health providers, policy makers, and third-party payers. Although all parties share a common goal and wish to use limited health-care resources to support interventions most likely to result in clinically meaningful improvements, there is often uncertainty about the most appropriate intervention for a particular patient. To help understand and evaluate the various commonly used nonsurgical approaches to CLBP, the North American Spine Society has sponsored this special focus issue of The Spine Journal, titled Evidence-Informed Management of Chronic Low Back Pain Without Surgery. Articles in this special focus issue were contributed by leading spine practitioners and researchers, who were invited to summarize the best available evidence for a particular intervention and encouraged to make this information accessible to nonexperts. Each of the articles contains five sections (description, theory, evidence of efficacy, harms, and summary) with common subheadings to facilitate comparison across the 24 different interventions profiled in this special focus issue, blending narrative and systematic review methodology as deemed appropriate by the authors. It is hoped that articles in this special focus issue will be informative and aid in decision making for the many stakeholders evaluating nonsurgical interventions for CLBP.

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.

Intradiscal thermal annuloplasty for discogenic pain: an outcome study

OBJECTIVES

Published studies of intradiscal thermal annuloplasty (IDTA) have shown at most 50% pain relief as an improved outcome with little focus on functional improvement in the treatment of discogenic pain. Previous studies have used a number of criteria for patient selection including low back pain unresponsive to conservative care, no compressive radiculopathy, positive provocative discography and absence of previous surgery at the same symptomatic level. The purpose of present study is to examine the hypothesis that additional inclusion criteria for patient selection such as disc height, absence of degenerative disc disease (DDD) in untreated discs, absence of herniated nucleus pulposus or lumbar canal stenosis may improve the outcome of treatment.

METHODS

In this prospective case-series study additional criteria of patient selection were introduced, namely disc height of at least 50%, no lumbar canal stenosis, one or two levels of DDD, no evidence of nucleus pulposus herniation on magnetic resonance image. Thirty-four patients were enrolled in the study and 32 of them were followed over a period of 12 months. The visual analog scale (VAS) pain score and seven activities of daily living (ADLs) were followed and reported on a scale from 0 to 10.

RESULTS

Sustained decrease of the VAS pain scores was observed from 3 to 12 months following IDTA. ADLs improved in all patients between 3 and 12 months post-treatment. Patients in the Bureau of Workers Compensation (BWC) group had a higher VAS score but showed the same level of improvement in ADLs as compared to commercial insurance or self-pay patients. In the non-BWC patient group an average VAS pain score decrease of more than 6 points on a 10-point scale was reported at 6 to 12 months following IDTA.

CONCLUSIONS

We found dramatic improvement of pain scores and ADLs following IDTA when strict patient selection was applied. We believe that IDTA is an effective, minimally invasive treatment for discogenic pain in properly selected patients.

Percutaneous thermocoagulation intradiscal techniques for discogenic low back pain

STUDY DESIGN

Systematic review.

OBJECTIVE

To systematically review the evidence on the efficacy, effectiveness, and safety of percutaneous thermocoagulation intradiscal techniques for discogenic low back pain.

SUMMARY OF BACKGROUND DATA

The intervertebral disc is thought to be the source of pain in a relevant proportion of cases of low back pain (LBP). Two percutaneous thermocoagulation intradiscal techniques have been described to treat discogenic LBP: percutaneous intradiscal radiofrequency thermocoagulation (PIRFT) and intradiscal electrothermal therapy (IDET).

METHODS

An electronic search was performed in MEDLINE, EMBASE, and the Cochrane Library databases up to 2005, to identify nonrandomized controlled trials and randomized controlled trials (RCTs) on those techniques. All relevant studies were methodologically assessed independently by 3 reviewers. RCTs were assessed following the criteria recommended by the Cochrane Back Review Group. A qualitative synthesis of results was performed.

RESULTS

Six studies were included with a total of 283 patients. Two open, nonrandomized trials (95 patients) showed positive results for IDET compared with rehabilitation and PIRFT. Results from 2 RCTs showed no differences between PIRFT and placebo, and between different PIRFT techniques. Two RCTs compared IDET with placebo. One suggested differences only in pain and in disability, while the best quality RCT showed no differences.

CONCLUSIONS

The available evidence does not support the efficacy or effectiveness of percutaneous thermocoagulation intradiscal techniques for the treatment of discogenic low back pain.

IDET: a critical appraisal of the evidence

Smith and Nephew (Endoscopy division, Andover, MA, USA) have estimated that 60,000 Intra-Discal Electrothermal Therapy (IDET) procedures have been performed world wide up to June 2005. Despite the large number of procedures performed, a critical appraisal of the evidence of efficacy of IDET has not appeared in the literature. This paper reviews the current evidence of clinical efficacy for IDET obtained via a systematic review of the literature. Studies were included if they used at least one of four specified primary outcome measures; pain intensity as assessed by a visual analogue score (VAS), global measurement of overall improvement, back specific functional status such as Oswestry disability Index (ODI) and return to work. Levels of evidence were assigned according to the hierarchy described by the Oxford Centre for Evidence-Based Medicine (www.cebm.net). Papers addressing possible mechanisms of action of IDET were not considered as the focus of the literature review was clinical effectiveness. Eleven prospective cohort studies (level II evidence) were reported on a total of 256 patients with a mean follow-up of 17.1 months (range 12-28 months). The mean improvement in the VAS for back pain was 3.4 points (range 1.4-6.5) and the mean improvement in ODI was 5.2 points (range 4.0-6.4). A total of 379 patients were reported in five retrospective studies (level III evidence). Between 13 and 23% of patients subsequently underwent surgery for low back pain within the study period. Two randomised controlled trials of IDET have been reported in the literature. The first randomised 64 patients (37 to IDET, 27 to Sham). The advantage for IDET patients amounted to 1.3 points on the VAS and seven points on the ODI. The second study randomised 57 subjects (38 to IDET, 19 to Sham) and showed no benefit from IDET over placebo. The evidence for efficacy of IDET remains weak and has not passed the standard of scientific proof.

Meta-Analysis of the Efficacy and Safety of Intradiscal Electrothermal Therapy (IDET)

OBJECTIVE

The objective of this study was to determine the representative outcomes of the intradiscal electrothermal therapy (IDET) procedure in terms of pain relief, reduction of disability, and risk of complications.

DESIGN

Meta-analysis, using a random-effects model. A Medline literature search was conducted using search terms associated with the IDET procedure including IDET, intradiscal electrothermal therapy, intervertebral disk, and annuloplasty.

OUTCOME MEASURES

The outcomes analyzed were the visual analog scale (VAS) assessment of pain, the bodily pain, and physical functioning subscales of the SF-36 health survey, and the Oswestry disability index.

RESULTS

From 1998 to March 2005, 62 peer-reviewed articles were identified regarding the IDET procedure. Forty-five articles were excluded, leaving a total of 17 unique published reports included in this review. The overall mean improvement in pain intensity was 2.9 points as measured by the VAS. The overall mean improvement in physical function was 21.1 points as measured by the SF-36. The overall mean improvement in bodily pain was 18.0 points as measured by the SF-36. The overall mean improvement in disability was 7.0 points as measured by the Oswestry disability index. The overall incidence of complications was 0.8%.

CONCLUSION

Although variation exists in the reported outcomes among the various studies of the IDET procedure, the pooled results of the published studies provide compelling evidence of the relative efficacy and safety of the IDET procedure.

A randomized, double-blind, controlled trial: intradiscal electrothermal therapy versus placebo for the treatment of chronic discogenic low back pain

STUDY DESIGN

A prospective, randomized, double-blind, placebo-controlled trial of intradiscal electrothermal therapy (IDET) for the treatment of chronic discogenic low back pain (CDLBP).

OBJECTIVES

To test the safety and efficacy of IDET compared with a sham treatment (placebo).

SUMMARY OF BACKGROUND DATA

In North America alone, more than 40,000 intradiscal catheters have been used to treat CDLBP. The evidence for efficacy of IDET is weak coming from retrospective and prospective cohort studies providing only Class II and Class III evidence. There is one study published with Class I evidence. This demonstrates statistically significant improvements following IDET; however, the clinical significance of these improvements is questionable.

METHODS

Patients with CDLBP who failed to improve following conservative therapy were considered for this study. Inclusion criteria included the presence of one- or two-level symptomatic disc degeneration with posterior or posterolateral anular tears as determined by provocative computed tomography (CT) discography. Patients were excluded if there was greater than 50% loss of disc height or previous spinal surgery. Fifty-seven patients were randomized with a 2:1 ratio: 38 to IDET and 19 to sham procedure (placebo). In all cases, the IDET catheter was positioned to cover at least 75% of the annular tear as defined by the CT discography. An independent technician connected the catheter to the generator and then either delivered electrothermal energy (active group) or did not (sham group). Surgeon, patient, and independent outcome assessor were all blinded to the treatment. All patients followed a standard postprocedural rehabilitation program. Independent statistical analysis was performed.

OUTCOME MEASURES

Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), Short Form 36 questionnaire (SF-36), Zung Depression Index (ZDI), and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and 6 months. Successful outcome was defined as: no neurologic deficit, improvement in LBOS of greater then 7 points, and improvement in SF-36 subsets (physical function and bodily pain) of greater than 1 standard deviation.

RESULTS

Baseline demographic data, initial LBOS, ODI, SF-36, ZDI, and MSPQ were similar for both groups. No neurologic deficits occurred. No subject in either arm showed improvement of greater than 7 points in LBOS or greater than 1 standard deviation in the specified domains of the SF-36. Mean ODI was 41.42 at baseline and 39.77 at 6 months for the IDET group, compared with 40.74 at baseline and 41.58 at 6 months for the placebo group. There was no significant change in ZDI or MSPQ scores for either group.

CONCLUSIONS

The IDET procedure appeared safe with no permanent complications. No subject in either arm met criteria for successful outcome. Further detailed analyses showed no significant change in outcome measures in either group at 6 months. This study demonstrates no significant benefit from IDET over placebo.

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.

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 < or = 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 degrees 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.

Radiofrequency Heating of Painful Annular Disruptions

OBJECTIVE

Although several studies have reported on outcomes following heating of annular tears with a thermoresistive catheter (SpineCATH), no data are available on the efficacy of thermal treatment with a flexible radiofrequency electrode (discTRODE). A prospective case-control study was conducted to determine the efficacy of radiofrequency heating of painful annular tears in the lumbar spine.

METHODS

After at least 6 months of conservative treatment, 46 patients were studied for the presence of single-level painful annular tears with magnetic resonance imaging and provocative discography. Thirty-one patients underwent heating of their annular tears with a flexible radiofrequency electrode placed across the posterior annulus. The remaining 15 patients, who mostly could not obtain funding for the procedure, continued with conservative management and acted as a control group. The Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and Medication Quantification Score (MQS) were obtained before and at 3-monthly intervals after treatment.

RESULTS

The VAS decreased significantly after the radiofrequency treatment, and this decrease persisted at 12 months of follow-up. The VAS did not change over 12 months in untreated control subjects. The decrease in VAS was significantly greater in the treated patients than the control subjects. The ODI also decreased in treated patients but not in control subjects. The MQS did not change in either group over the 12-month follow-up period.

CONCLUSIONS

Radiofrequency heating of annular tears can lead to an improvement in the pain of internal disc disruption. The improvement gained by this treatment method is significantly better than that obtained from conservative management.

Intradiscal Thermal Annuloplasty for the Treatment of Lumbar Discogenic Pain in Patients with Multilevel Degenerative Disc Disease

Symptomatic degenerative disc disease (DDD) may lead to significant deterioration of quality of life and increased disability. Intradiscal thermal annuloplasty (IDTA) is a minimally invasive treatment for painful DDD. We hypothesized that there may be an improvement in pain scores and the pain disability index (PDI) of patients who have multilevel DDD after IDTA. Patients 24-66 yr old, male and female with multilevel DDD (MDDD) and matched 1 or 2 level DDD (1,2-DDD) patients were enrolled in the study. Visual analog pain scale (VAS) score and PDI were observed for 12 mo. The 1,2-DDD patient group had a 2.5 +/- 2.4 VAS score at 12 mo after annuloplasty compared to 7.7 +/- 2 before the procedure. The MDDD VAS score was 4.9 +/- 2.9 at 12 mo compared to 7.4 +/- 1.8 before the procedure. Similar improvements in PDI were found. The pain relief and PDI were significantly better in patients with 1,2-DDD than in the MDDD group (P = 0.0037 and P = 0.041, respectively). We concluded that IDTA is an effective treatment of discogenic pain and that the number of discs affected by degeneration is an important determinant of the procedure outcome.

Sedation with ketamine during intradiscal electrothermal therapy

STUDY DESIGN

A technical report.

OBJECTIVES

To present a new and improved method to sedate patients during intradiscal electrothermal therapy (IDET).

SUMMARY OF BACKGROUND DATA

The current standard of practice is to sedate patients with short-acting benzodiazepines and opioids during the coagulation phase of intradiscal electrothermal therapy. There are few data on the subject, but it is estimated that between 5% and 20% of IDET procedures are either aborted early or switched to a lower heating temperature because patients cannot tolerate the optimal, recommended heating protocol. A priori, one must assume these patients are more likely to fail their treatment than those who are able to tolerate complete heating.

METHODS

The authors treated 9 patients receiving intradiscal electrothermal therapy who were unable to tolerate the latter portion of their heating protocol secondary to axial low back pain despite high doses of opioids, with low dose ketamine. This paper outlines our experience with "rescue" doses of ketamine, along with the rationale and guidelines for its use.

RESULTS

After receiving ketamine, all patients were able to complete the full intradiscal electrothermal therapy heating protocol. The rescue dosages of ketamine ranged from 15 to 55 mg. The dosages of midazolam used to prevent the psychomimetic effects of ketamine ranged from 3 to 7 mg. Oxygen saturation and hemodynamic parameters did not change significantly after ketamine was administered, and all patients remained responsive throughout the procedure. There were no adverse effects or complications reported.

CONCLUSIONS

When used judiciously to treat axial back pain during intradiscal electrothermal therapy heating, ketamine is a safe and effective rescue medication.

Ergonomic Pain--Part 2: Differential Diagnosis and Management Considerations

Work-related musculoskeletal disorders (MSDs) can produce ergonomic pain in several different regions of the body, including the shoulder, elbow, wrist and hand, lumbar spine, knee, and ankle/foot. Each family of disorders is distinctive in presentation and requires diagnosis-specific interventions. Because of the complex nature of these disorders, management approaches may not always eliminate symptoms and or completely restore patient function to a level found prior to symptom onset. As a consequence, ergonomic measures should be implemented to reduce the overload on tissue and contribute to patient recovery. However, functional limits may persist and the clinician must make further decisions regarding a person's functional status in the chronic stages of the patient's care.

[Diagnostics and minimally invasive therapy for chronic low back pain]

Chronic low back pain is one of the most frequent causes for seeking medical help in Germany. Many factors play a causal role in its pathogenesis. This is where the dilemma resides in narrowing down the diagnosis and deciding on subsequent therapeutic intervention. There is overall agreement on the concept of when it is expedient to initiate further diagnostic measures. With the exception of clear pathomorphological findings and the presence of cardinal symptoms or warning signs, so-called "red flags", primary back pain should not be subjected to any specific diagnostic tests and therapy during the first 3 months. We present well-established techniques for blockade, discography, and minimally invasive treatment options such as cryotherapy, procedures for thermal ablation, and intradiscal electrotherapy. Vertebroplasty, currently a frequently applied method, is also included in the discussion of minimally invasive treatment for chronic low back pain.

Outcomes of workers' compensation claimants with low back pain undergoing intradiscal electrothermal therapy

STUDY DESIGN

Case series.

OBJECTIVE

To describe the outcomes of workers' compensation (WC) claimants who have had a lumbar intradiscal electrothermal therapy (IDET) procedure.

SUMMARY OF BACKGROUND DATA

IDET was developed as a less invasive treatment alternative to fusion after failure of conservative treatment for discogenic low back pain (LBP). Initial IDET case series from single practices have reported improved pain, function, and return to work outcomes. Little is known about results when performed by a variety of providers or in WC populations.

MATERIALS AND METHODS

LBP cases that underwent IDET between December 1, 1998 and February 29, 2000 were identified from WC records. Data sources included hardcopy claim files, administrative medical billing data, and computerized claim file narrative reports. Outcomes included narcotic use 6 months or more after IDET, additional invasive treatment after IDET (low back injections or surgery), and improved work status 24 months after IDET.

RESULTS

One hundred forty-two cases from 23 states were identified, with 97 different providers performing the procedure. Mean duration of symptoms before IDET was 26 months. Mean follow-up duration after IDET was 22 months. Ninety-six (68%) of the cases did not meet one or more of the published inclusion criteria. Seventy-eight cases (55%) received at least two narcotic prescriptions 6 months or more after IDET. Fifty-three (37%) had at least one lumbar injection and 32 (23%) had lumbar surgery after IDET. A total of 55 (39%) were working at 24 months after IDET; of these, 28 (20%) were not working and 27 (19%) were working before IDET. Narcotic use after IDET was associated with narcotic use before IDET, the same provider performing discography and IDET (provider self-referral), and positive signs of radiculopathy (C = 0.80). Need for invasive lumbar procedures after IDET were associated with provider self-referral, narcotic use before IDET, and older age (C = 0.73). Continued work absence after IDET was associated with provider self-referral, male gender, litigation, narcotic use before IDET, and older age (C = 0.83). Conformance with published selection criteria for IDET was not associated with provider self-referral or outcomes, nor was duration before IDET associated with outcomes.

CONCLUSION

The procedure may be less effective when performed by a variety of providers than suggested by initial case series performed by single providers or practices in work-related LBP cases. Provider self-referral and narcotic use before IDET are significant risk factors for poor outcomes. Randomized controlled trials are needed to determine whether there is a subset of patients with discogenic back pain who derive substantial and sustained benefit from this procedure.

A randomized, placebo-controlled trial of intradiscal electrothermal therapy for the treatment of discogenic low back pain

BACKGROUND

Intradiscal electrothermal therapy (IDET) is a treatment for discogenic low back pain the efficacy of which has not been rigorously tested.

PURPOSE

To compare the efficacy of IDET with that of a placebo treatment.

STUDY DESIGN/SETTING

Randomized, placebo-controlled, prospective trial.

PATIENT SAMPLE

Patients were recruited by referral and the media. No inducements were provided to any patient in order to have them participate. Of 1,360 individuals who were prepared to submit to randomization, 260 were found potentially eligible after clinical examination and 64 became eligible after discography. All had discogenic low back pain lasting longer than 6 months, with no comorbidity. Thirty-seven were allocated to IDET and 27 to sham treatment. Both groups were satisfactorily matched for demographic and clinical features.

METHODS

IDET was performed using a standard protocol, in which the posterior annulus of the painful disc was heated to 90 C. Sham therapy consisted of introducing a needle onto the disc and exposing the patient to the same visual and auditory environment as for a real procedure. Thirty-two (85%) of the patients randomized to the IDET group and 24 (89%) of those assigned to the sham group complied fully with the protocol of the study, and complete follow-up data are available for all of these patients.

OUTCOME MEASURES

The principal outcome measures were pain and disability, assessed using a visual analog scale for pain, the Short Form (SF)-36, and the Oswestry disability scale.

RESULTS

Patients in both groups exhibited improvements, but mean improvements in pain, disability and depression were significantly greater in the group treated with IDET. More patients deteriorated when subjected to sham treatment, whereas a greater proportion showed improvements in pain when treated with IDET. The number needed to treat, to achieve 75% relief of pain, was five. Whereas approximately 40% of the patients achieved greater than 50% relief of their pain, approximately 50% of the patients experienced no appreciable benefit.

CONCLUSIONS

Nonspecific factors associated with the procedure account for a proportion of the apparent efficacy of IDET, but its efficacy cannot be attributed wholly to a placebo effect. The results of this trial cannot be generalized to patients who do not fit the strict inclusion criteria of this study, but IDET appears to provide worthwhile relief in a small proportion of strictly defined patients undergoing this treatment for intractable low back pain.

Percutaneous disc decompression in the management of chronic low back pain

Although there has not yet been a percutaneous intradiscal procedure developed with the superior therapeutic efficacy of open surgery, these procedures are less invasive and avoid the complications of open surgery. All of these procedures have limitations, but their therapeutic effect increases substantially given careful patient selection and proper technique. New appliances and techniques to treat LBP or sciatica continue to evolve, and numerous controlled studies are underway. With tremendous technologic advances, use of minimally invasive techniques to treat chronic back pain continues to expand.

A Randomized Controlled Trial of Radiofrequency Denervation of the Ramus Communicans Nerve for Chronic Discogenic Low Back Pain

OBJECTIVE

The objective of this study was to determine the efficacy of percutaneous radiofrequency (RF) thermocoagulation of the ramus communicans nerve in patients suffering from chronic discogenic low back pain.

METHODS

Forty-nine patients who suffered chronic discogenic low back pain at only 1 painful vertebral level, and whose pain continued after undergoing intradiscal electrothermal annuloplasty (IDET), were randomly assigned to 1 of 2 treatment groups. The lesion group (n = 26) received RF thermocoagulation of the ramus communicans nerve. Patients in the control group (n = 23) received an injection of lidocaine without radiofrequency. Visual analog scale (VAS) pain scores, analgesic requirements, SF-36 subscales, and the overall patient satisfaction with the procedure were tabulated.

RESULTS

The average follow-up period was 4 months. The patient-reported VAS pain scores were significantly lower (P < 0.05) in the lesion group. The scores of the RF lesion group improved by a mean increase of 11.3 points (P < 0.05) on the SF-36 bodily pain subscale, and by a mean increase of 12.4 points on the physical function subscale (P < 0.05). In a follow-up analysis within the RF lesion group, VAS pain scores improved by a mean reduction of 3.32 (P = 0.001). The scores improved by a mean increase of 14.5 points (P = 0.005) on the SF-36 bodily pain subscale and 15.2 points(P = 0.002) on the physical function subscale within the RF lesion group. One patient in the lesion group complained of mild lower limb weakness, but he completely recovered at postoperative 15 days without any serious problems.

DISCUSSION

In patients with chronic discogenic low back pain, percutaneous RF denervation of the ramus communicans nerve should be considered as a treatment option.

Does intradiscal electrothermal therapy denervate and repair experimentally induced posterolateral annular tears in an animal model?

STUDY DESIGN

The effects of intradiscal electrothermal therapy (IDET) on intervertebral discs in sheep were studied experimentally.

OBJECTIVES

Posterolateral annular lesions were experimentally induced and allowed to mature for 12 weeks in the intervertebral discs of sheep. IDET was performed in an attempt to denervate and repair the annular lesion. The histologic and immunohistochemical effects of IDET were studied.

SUMMARY OF BACKGROUND DATA

IDET continues to be used as a minimally invasive treatment for chronic discogenic low back pain, with success rates reported in up to 70% of cases. The mechanism of action by which IDET exerts its effect is poorly understood. Proposed mechanisms include the contraction of collagen and the coagulation of annular nociceptors. An ovine model was used firstly to induce a posterolateral annular lesion, secondly to assess the innervation of such a lesion, and thirdly to assess the effect of IDET on this innervation.

MATERIALS AND METHODS

Posterolateral annular incisions were made in 40 lumbar discs of 20 sheep. Twelve weeks were allowed for each annular lesion to mature. IDET was then performed in the disc with the posterolateral annular tear and in another control level. IDET was performed using a modified intradiscal catheter (Spine-CATH; Oratec Interventions, Menlo Park, CA). Temperatures were recorded in the nucleus (TN) and the posterior annulus (TPA). The spines were harvested at predetermined intervals up to 18 months. Histologic sections of the discs were graded for disc morphology to assess degeneration and immunohistochemical staining to assess potential denervation.

RESULTS

Vascular granulation tissue consistent with a healing response was observed in the posterior annular tear of all incised discs from 12 weeks. Protein gene product 9.5 (PGP 9.5) positive nerve fibers were clearly identified in the adjacent periannular tissue and the outer few lamellae of the posterior annulus. During the IDET procedure, the mean maximum TPA was 63.6C and the mean maximum TN was 67.C.At sacrifice, the number of nerve fibers identified in the posterior annular tear was the same for those specimens that had undergone IDET and those that had not. From 6 weeks after IDET, there was evidence of thermal necrosisin the inner annulus and adjacent nucleus but sparing the periphery of the disc.

CONCLUSIONS

Vascular granulation tissue and posterior annular neo-innervation was observed in the experimentally induced posterolateral annular lesion. IDET delivered at 90C in the sheep consistently heated the posterior annulus and the nucleus to a temperature normally associated with coagulation of nociceptors and collagen contraction. IDET did not denervate the posterior annular lesion. Thermal necrosis was observed within the inner annulus and adjacent nucleus from 6 weeks after IDET. The reported benefits from IDET appear to be related to factors other than denervation and repair.

Radiofrequency lesioning using two different time modalities for the treatment of lumbar discogenic pain: a randomized trial

STUDY DESIGN

A prospective randomized trial.

OBJECTIVE

To evaluate the efficacy of percutaneous intradiscal radiofrequency thermocoagulation by modifying the duration of heating, using two different time methods, for relieving pain and improving functional disability.

SUMMARY OF BACKGROUND DATA

Lumbar discogenic pain is the major problem in lumbar degenerative disc disease that percutaneous intradiscal radiofrequency thermocoagulation has been suggested for as a nonsurgical invasive treatment technique for lumbar discogenic pain. In a previous controlled study, this method was found to be ineffective with 8 weeks of follow-up.

MATERIALS AND METHODS

Sixty patients with chronic low back pain were selected for provocative discography to diagnose the discogenic pain and to locate the discs to be treated. From this group, 39 patients were randomly selected and divided into two groups. In the first group, treatment was performed for 120 seconds, and in the second group for 360 seconds, both at 80C. Patients were assessed with a visual analogue scale for pain relief and functional improvement. Evaluations were performed before, immediately after treatment, at 1 and 2 weeks, and at 1, 3, and 6 months after the procedure.

RESULTS

A total of 39 patients with positive provocative discographies were found to eligible for the study. There were no statistical differences in pain relief and functional improvement between two groups (P > 0.05). The immediate, 1-week and 2-week, and 1-month visual analogue scale (VAS) scores were decreased significantly in both groups when comparing them with the pretreatment scores (P < 0.05). However, the final values after 6 months were similar to those measured at the beginning of the study (P > 0.05).

CONCLUSION

Percutaneous intradiscal radiofrequency thermocoagulation has been suggested and performed to relieve discogenic pain. In the previous controlled study, no effective pain relief has been obtained. In this study, the authors increased the duration of radiofrequency thermocoagulation to improve the effectiveness of this method. Yet, the authors have not found any significant differences between the application of lesioning at two different times in percutaneous intradiscal radiofrequency thermocoagulation.

Intradiscal electrothermal therapy: a treatment option in patients with internal disc disruption

STUDY DESIGN

A literature review was conducted.

OBJECTIVES

To review the anatomy, pathophysiology, diagnosis, procedure, and clinical results of intradiscal electrothermal therapy (IDET).

SUMMARY OF BACKGROUND DATA

Low back pain is a major physical and socioeconomic entity. A significant percentage of low back pain is attributable to internal disc disruption. The management of internal disc disruption has traditionally been limited to either conservative treatment or spinal fusion. IDET has been performed as an alternative to these therapies.

METHODS

The available literature was reviewed.

RESULTS

Scientific data regarding the pathophysiology, biologic effects, and clinical results are relatively scarce. Early biomechanical and histologic investigations into the effects of IDET are conflicting. However, in early prospective human trials, IDET seems to provide some benefit with little risk.

CONCLUSIONS

IDET is potentially beneficial treatment for internal disc disruption in carefully selected patients as an alternative to spinal fusion. More basic science and clinical research with long-term follow-up evaluation is necessary.

Risk factors for failure and complications of intradiscal electrothermal therapy: a pilot study

STUDY DESIGN

A bi-institutional, retrospective clinical data analysis.

OBJECTIVES

To determine risk factors for failure and complications of intradiscal electrothermal therapy, a treatment for discogenic back pain.

SUMMARY OF THE BACKGROUND DATA

Intradiscal electrothermal therapy is a relatively new treatment for discogenic back pain. Though previous studies have shown it to be an effective treatment, there are few published studies examining complications and none examining risk factors for failure.

METHODS

The authors treated 79 patients with discogenic back pain using intradiscal electrothermal therapy. Complications were assessed by patient report and, when indicated, further diagnostic testing. Success or failure was determined by visual analogue pain scores at 6-month follow-up. Variables examined for their relationship to failure and complications were age, sex, duration of pain, number of levels heated, smoking history, diabetes, obesity, leg pain, and previous back surgery.

RESULTS

Forty-eight percent of patients reported more than 50% pain relief at their 6-month follow-up. There were eight complications (10%), most of which were self-limited and transient. The only risk factor associated with intradiscal electrothermal therapy failure was obesity (P = 0.01). Whereas 54% of nonobese patients reported good pain relief at 6 months, only one out of 10 obese patients had successful intradiscal electrothermal therapy. The obese patients in our study were more likely to have a complication from intradiscal electrothermal therapy than they were to obtain pain relief.

CONCLUSION

The only risk factor found to be associated with IDET outcome was obesity, which was a strong predictor of failure. Obesity should be considered a relative contraindication to performing IDET.

Disc stimulation and patterns of referred pain

STUDY DESIGN

Prospective, within-subjects, observational experimental design.

OBJECTIVES

To determine the pattern of pain response to noxious stimulation of the intervertebral disc.

SUMMARY OF BACKGROUND DATA

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

A giant herniated disc following intradiscal electrothermal therapy

The introduction of intradiscal electrothermal therapy for the management of discogenic back pain has been met with intense interest over the past few years. During this time there have been several noncontrolled studies published on the procedure, most of which have shown excellent outcomes but few, if any, complications. The authors describe a 29-year-old, 152-kg active duty male soldier who underwent two-level intradiscal electrothermal therapy for L4-L5 and L5-S1 discogenic pain. Before the procedure, the patient had a small L5-S1 contained herniation, with no signs of radiculitis. Postprocedure, the patient developed radicular symptoms and was noted on MRI to have a large L5-S1 disc herniation effacing the left S1 nerve root. Follow-up discography revealed a negative discogram at L4-L5. The patient proceeded to undergo a single-level lumbar fusion, which resulted in nearly complete relief of his radicular and axial low back pain. Two years post-surgery, he is off all narcotic medications and continues to work full-time as a soldier. This case illustrates both the potential benefits and complications that may be associated with intradiscal electrothermal therapy.

Two-year follow-up of a controlled trial of intradiscal electrothermal anuloplasty for chronic low back pain resulting from internal disc disruption

BACKGROUND

On the basis of observational data, intradiscal electrothermal anuloplasty (IDETA) has been implemented as a treatment for back pain resulting from internal disc disruption.

PURPOSE

To assess the efficacy of IDETA.

STUDY DESIGN

Prospective cohort study with comparison group and 2-year follow-up.

PATIENT SAMPLE

Of 53 patients who satisfied the diagnostic criteria for internal disc disruption, 36 were allocated to a treatment group and 17 to a comparison group, according to whether their insurer approved treatment with IDETA.

OUTCOME MEASURES

Outcomes were assessed in terms of relief of pain, return to work and use of opioids to treat persisting pain.

METHODS

The treatment group underwent IDETA. The comparison group underwent a conventional rehabilitation program. Outcomes were assessed at 3 months, 12 months and 2 years after treatment.

RESULTS

As a group, the comparison patients exhibited no significant improvement in their pain at any time. One was partially relieved, but no patient was completely relieved at either 12 or 24 months. The patients treated with IDETA exhibited significant improvements in their median pain scores, which were sustained at 12 and 24 months. At 24 months, 54% of these patients had achieved at least 50% relief of their pain, no longer used opioids and were at work. Seven patients (20%) were totally free of pain and at work at 24 months.

CONCLUSIONS

The long-term results of IDETA are stable and enduring. It is not universally successful, but 54% of patients can reduce their pain by half, and one in five patients can expect to achieve complete relief of their pain.

Alternative strategies for lumbar discectomy: intradiscal electrothermy and nucleoplasty

In recent years the general trend in spinal surgery has been one of reductionism and minimalization. A number of techniques have recently been developed that are applicable in the treatment of lumbar disc herniation and discogenic pain due to degenerative disc disease. The purpose of this manuscript is to examine two newer percutaneous disc treatment techniques, intradiscal electrothermal therapy (IDET) anuloplasty and nucleoplasty. The authors review the appropriate clinical treatment criteria, techniques, and lessons learned after performing these procedures in more than 100 patients.

The IDET involves the percutaneous insertion of a specially designed thermal resistance probe followed by controlled heating of the intervertebral disc. This may result in disc shrinkage and reduction in pain. The nucleoplasty procedure involves the percutaneous removal of disc material by using a low-temperature resister probe to disintegrate and evacuate disc material, followed by thermal treatment of adjacent residual disc material. To date, no study has been published in which investigators examine the outcomes of this procedure for the treatment of radicular leg pain and low-back pain.

Both IDET and nucleoplasty appear to be safe procedures. The IDET procedure may be an alternative to lumbar interbody fusion. Although its long-term role is being defined, this technique appears to provide intermediate-term relief of pain in a population of patients with discogenic low-back pain. Nucleoplasty may provide a percutaneous alternative to microdiscectomy in selected cases.

Intradiscal electrothermal treatment for chronic discogenic low back pain: prospective outcome study with a minimum 2-year follow-up

STUDY DESIGN

Prospective longitudinal study with a minimum 2-year follow-up.

OBJECTIVE

To assess the long-term outcome of a group of patients with chronic discogenic low back pain who had failed to improve with comprehensive nonoperative care and who were subsequently treated with intradiscal electrothermal therapy (IDET).

SUMMARY OF BACKGROUND DATA

Previous reports of patient outcomes at 1 year after IDET have demonstrated statistically significant improvement.

METHODS

The study group comprised 58 patients with chronic symptoms of more than 6 months who failed to improve with nonoperative care and subsequently underwent IDET. VAS pain scores, SF-36 scores, and sitting tolerance times were collected pretreatment and at 6, 12, and 24 months.

RESULTS

Mean duration of pre-IDET symptoms was 60.7 months. The minimum follow-up at data collection was 24 months. The study group (n = 58) demonstrated a significant improvement in pain as demonstrated by statistically significant improvement in VAS scores and bodily pain SF-36 scores. The IDET-treated group demonstrated a significant improvement in physical function as noted by statistically significant improvement in sitting tolerance times and physical function SF-36 scores. Bodily pain and physical function scores demonstrated significant improvement between the 1- and 2-year observation points. Additionally, quality of life improvement was demonstrated by a statistically significant improvement in all the SF-36 subscales.

CONCLUSIONS

A cohort of patients with chronic discogenic low back pain who had failed to improve with comprehensive nonoperative care demonstrated a statistically significant improvement in pain, physical function, and quality of life at 2 years after IDET.

Intradiscal electrothermal annuloplasty: the IDET procedure

Intradiscal electrothermal annuloplasty is a minimally invasive procedure for the treatment of lumbar degenerative disc disease. This procedure has been used in the lumbar spine of patients who have failed conservative treatment regimens and who might otherwise be candidates for a spinal fusion procedure. As this is a new, recently developed procedure, there is only relatively short-term follow-up data available, and as such, the procedure has not been widely accepted.