Literature References Supporting the Technique IDET LITERATURE SUPPORT Anesth Analg. 2004 Aug;99(2):472-6, table of contents. Intradiscal thermal annuloplasty for the treatment of lumbar discogenic pain in patients with multilevel degenerative disc disease. Kapural L, Mekhail N, Korunda Z, Basali A. Pain Management Center, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Desk C25, Cleveland, OH 44195, USA. Kapural@ccf.org 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 Arch Phys Med Rehabil. 2003 Jan;84(1):23-8. Treatment of chronic lumbar diskogenic pain with intradiskal electrothermal therapy: a prospective outcome study. Lutz C, Lutz GE, Cooke PM. Physiatry Service, Hospital for Special Surgery, New York, NY 10021, USA. OBJECTIVE: To determine the clinical efficacy of intradiskal electrothermal annuloplasty in treating patients with chronic constant lumbar diskogenic pain who have not responded to at least 6 months of aggressive nonoperative care. DESIGN: Prospective case series. SETTING: Academic-affiliated private physiatry practice. PARTICIPANTS: Thirty-three patients with chronic constant lumbar diskogenic pain of more than 6 months in duration diagnosed with history and physical examination, with concordant pain on provocative pressure-controlled lumbar diskography, and with symptomatic annular tears and/or protrusions less than 5mm, who did not respond to aggressive nonoperative care. INTERVENTION: Intradiskal electrothermal annuloplasty. MAIN OUTCOME MEASURES: Visual analog scale (VAS) pain scores for the back and for the lower extremity, the Roland-Morris Disability Questionnaire (RMDQ), and the North American Spine Society Patient Satisfaction Index. RESULTS: A total of 33 patients, with mean age of 40 years and a mean duration of symptoms of 46 months, were observed with a mean follow-up of 15 months. Relief of pain and improvement in physical function were associated with a mean change in the VAS score of 3.9 (P<.001), a mean change in the lower-extremity VAS score of 3.7 (P<.001), and a mean change in the RMDQ of 7.3 (P<.001). For patient satisfaction, 75.7% reported that they would undergo the same procedure for the same outcome. Complete pain relief was achieved in 24% of the patients, and partial pain relief in 46% of the patients. CONCLUSIONS: Intradiskal electrothermal annuloplasty offers a safe, minimally invasive treatment option for carefully selected patients with chronic lumbar diskogenic pain who have not responded to aggressive nonoperative care. Copyright 2003 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Spine. 2002 Nov 15;27(22):2621-6. Intradiscal electrothermal therapy used to manage chronic discogenic low back pain: new directions and interventions. Wetzel FT, McNally TA, Phillips FM. Section of Orthopaedic Surgery and Rehabilitation and Anesthesia and Critical Care, University of Chicago Spine Center, Chicago, Illinois 60640, USA. twetzel@mcis.bsd.uchicago.edu STUDY DESIGN: Retrospective literature review. OBJECTIVES: 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. SUMMARY OF BACKGROUND DATA: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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. Spine. 2004 Apr 16;29(7):752-6. The IDET procedure for chronic discogenic low back pain. Davis TT, Delamarter RB, Sra P, Goldstein TB. Spine Institute at Saint John's Health Center, Santa Monica, CA 90404, USA. tdavis@espineinstitute.com STUDY DESIGN: Retrospective study with independent evaluation of patient outcomes approximately 1 year post-intradiscal electrothermal therapy (IDET). OBJECTIVE.: To assess functional status, symptoms, and subsequent treatments of patients treated with IDET. SUMMARY OF BACKGROUND DATA: IDET was introduced as a procedure for discogenic pain. Several studies reported improvement in >70% of patients. METHODS: Seventeen physicians referred 60 patients. Each patient had a positive discogram and had been treated with IDET. Patients were contacted approximately 1 year post-IDET, answered a telephone interview, and completed a self-administered questionnaire. Overall patient satisfaction, pain, functional and work status, analgesic usage, and subsequent treatments were noted. Kaplan-Meier survival curve was generated to predict the percentage that would undergo lumbar surgery after IDET. RESULTS: Average age was 40 years (range 25-64 years) with 66% males and 34% females. Of the 44 patients who responded, 6 patients had a lumbar surgery within 1 year. Their outcomes were excluded from descriptive analysis; 97% continued to have back pain, 11 (29%) reported more pain post versus pre-IDET, 15 (39%) had less pain, and 11 (29%) reported no change; 11 (29%) reported using more pain medication post-IDET, 10 (26%) used the same, 12 (32%) used less, and 5 (13%) used none; 19 (50%) were dissatisfied with IDET, 14 (37%) were satisfied, and 5 (13%) were undecided; 20 (53%) would have the procedure again, 12 (31%) would not, and 6 (16%) were unsure. Most patients wore a brace >6 hours/day after surgery (duration 1-15 months). Sixteen (42%) were employed full-time pre-IDET and 11 (29%) were employed full-time post-IDET. CONCLUSION: At 1-year post-IDET, half of patients were dissatisfied with their outcome. The percentage of patients on disability remained constant. The estimated proportion of patients undergoing fusion was predicted to be 15% at 1 year and 30% at 2 years. Spine J. 2004 Jan-Feb;4(1):27-35. A randomized, placebo-controlled trial of intradiscal electrothermal therapy for the treatment of discogenic low back pain. Pauza KJ, Howell S, Dreyfuss P, Peloza JH, Dawson K, Bogduk N. Texas Spine and Joint Hospital, 1814 Roseland Boulevard, Tyler, TX 75701, USA. kevinpauza@tyler.net 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. Spine. 2002 May 1;27(9):966-73; discussion 973-4. Comment in: Spine. 2002 Dec 1;27(23):2741; author reply 2741. Spine. 2002 Dec 1;27(23):2742; author reply 2742. Intradiscal electrothermal treatment for chronic discogenic low back pain: prospective outcome study with a minimum 2-year follow-up. Saal JA, Saal JS. SOAR, Physiatry Medical Group, Menlo Park, California 94025, USA. gbdubuk@ix.netcom.com 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. Spine. 2000 Oct 15;25(20):2622-7. Intradiscal electrothermal treatment for chronic discogenic low back pain: a prospective outcome study with minimum 1-year follow-up. Saal JA, Saal JS. SOAR, Physiatry Medical Group, Menlo Park, CA 94025, USA. STUDY DESIGN: Prospective case series. OBJECTIVE: To determine the outcome of patients with chronic low back pain whose symptoms did not improve with aggressive nonoperative care and who chose (intradiscal electrothermal anuloplasty) IDET as an alternative to chronic pain management or interbody fusion surgery. SUMMARY OF BACKGROUND DATA: Patients with unremitting chronic discogenic low back pain are faced with the choice of long-term pain management or fusion surgery. Intradiscal electrothermal anuloplasty (IDET) was developed as an alternative minimally invasive treatment. MATERIALS AND METHODS: Sixty-two patients from the author's practice who had chronic low back pain unresponsive to nonoperative care, no evidence of compressive radiculopathy, and concordant pain reproduction at one or more disc levels on provocative discography were enrolled in the study. Visual analog scale (VAS) pain scores and Short Form (SF)-36 Health Status Questionnaire Physical Function subscale and SF-36 Bodily Pain subscale scores were assessed at baseline and at least 1 year later. RESULTS: Mean follow-up was 16 months, and mean preoperative duration of symptoms was 60 months. Baseline and follow-up outcome measures demonstrated a mean change in VAS score of 3.0 (P < 0.001), mean change in SF-36 physical function of 20 (P < 0.001), and mean change in SF-36 bodily pain of 17 (P < 0.001). Symptoms improved in 44 (71%) of 62 of the study group on the SF-36 physical function subscale, in 46 (74%) of 62 on the SF-36 Bodily Pain subscale, and in 44 (71%) of 62 on the VAS scores. Twelve (19%) of 62 of the patients did not show improvement on any scale. CONCLUSION: A cohort of patients with chronic unremitting low back pain of discogenic origin whose symptoms had failed to improve with aggressive nonoperative care demonstrated a statistically significant and clinically meaningful improvement on the SF-36 and the VAS scores at a minimum follow-up of 1 year after IDET. The positive results should be validated with placebo-controlled randomized trials and studies that compare IDET with alternative treatments.-