The following non-randomized prospective studies have two or more of years follow-up data on the IDET* procedure:
Saal JA, Saal JS. Intradiscal electrothermal treatment for chronic discogenic low back pain: prospective outcome study with minimum 2-year follow-up. Spine. 2002;27:966-974.
Saal JA, Saal JS. Intradiscal electrothermal treatment for chronic discogenic low back pain: a prospective outcome study with minimum 1-year follow-up. Spine. 2000;25:2622–2627.
The two published reports above use the same data set. In this prospective study, assessments were conducted at baseline and 6, 12, and 24 months post-procedure in 58 patients:
- Mean change in VAS at 12 months was 3.0 (P<0.001). A change of 1.8 to 1.9 in patients with chronic low back pain is regarded as clinically significant.
- Mean change in SF-36 physical function at 12 months was 20.0 (P<0.001). Threshold values for clinically significant change in SF-36 in patients with chronic low back pain vary across studies and by subscale (range: 0.5–24.5).
- Mean change in SF-36 bodily pain at 12 months was 17 (P<0.001).
- Symptoms improved in 71% of patients (VAS and SF-36) at 12 months.
- Twelve patients (19%) did not show any improvement at 12 months.
- Clinically significant improvement in pain, physical function, and quality of life measured by improvement in VAS and SF-36 scores were noted at 2-year follow-up.
- No patient treated with the IDET procedure had a complication or adverse event.
Freedman BA, Cohen SP, Kuklo TR, Lehman RA, Larkin P, Giuliani JR. Intradiscal electrothermal therapy (IDET) for chronic low back pain in active-duty soldiers: 2-year follow-up.Spine J. 2003;3: 502-509.
Thirty-six active-duty soldiers who underwent a single IDET procedure were assessed at 6 months. Thirty-one (86%) were available for a final follow-up 24-46 months after treatment. Data were collected by questionnaire and clinical chart review. Success was defined as ≥ 50% decrease in pain from baseline. Success rates were as follows:
- 47% (17/36) at 6 months
- 16% (5/31) at last follow-up
At final follow-up, 16 of 31 (52%) had a persistent decrease in VAS pain score of > 2 points, but early results diminished with time. Nineteen of 31 soldiers were still on active duty at a minimum of 24 months after the procedure. Five transient complications were reported, all within the first month post-procedure.
Wetzel FT, Andersson GBJ, Peloza JH, Rashbaum RF, Lee CK, Yuan HA, Phillips FM, An HS. Intradiscal electrothermal therapy (IDET) to treat discogenic low back pain: two year results of a multi-center prospective cohort study. Presented at the 16 th Annual Meeting of the North American Spine Society. November 2001. Abstract.
Seventy-eight patients were followed up at 1 and 2 years post-procedure. At 2 years, 75% compliance was reported. Two patients were withdrawn from the study. Results at 2 years were as follows:
- 88% would definitely or probably choose the same treatment.
- 61% were performing 100% of their job vs 23% of patients before treatment.
- Only 18% required subsequent back surgery.
Proven Reduction in Pain
Proven Increase in Functioning 
In this multicenter study of 78 patients, the IDET procedure was shown to significantly reduce pain and significantly improve physical function in patients observed 24 months after the treatment1.
1 Wetzel FT, Andersson GBJ, Peloza JH, Rashbaum RF, Lee CK, Yuan HA, Phillips FM, An HS. Intradiscal electrothermal therapy (IDET) to treat discogenic low back pain: two year results of a multi-center prospective cohort study. Presented at the 16 th Annual Meeting of the North American Spine Society. November 2001. Abstract.
Bogduk N, Karasek M. Two-year follow-up of a controlled trial of intradiscal electrothermal anuloplasty for chronic low back pain resulting from internal disc disruption. Spine J. 2002;2:343-350.
Karasek M, Bogduk N. Twelve-month follow-up of a controlled trial of intradiscal thermal anuloplasty for back pain due to internal disc disruption. Spine. 2000;25(20):2601-2607.
The two published reports above use the same data set. Of 53 patients recruited for this study, 17 were refused insurance coverage and acted as a control group for the 36 patients who underwent the IDET procedure. Patients were followed up 3 months and 1 and 2 years post-procedure.
- The control group showed no significant improvement.
- The IDET procedure group showed significant improvement in median pain scores at 1 and 2 years. At 2 years post-procedure:
- 54% of patients had 50% relief of pain, no opioid use, and were back at work
- 20% were pain free and back at work
Lee MS, Cooper G, Lutz, GE, Lutz C, Hong HM. Intradiscal electrothermal therapy (IDET) for treatment of chronic lumbar discogenic pain: a minimum 2-year clinical outcome study. Pain Physician. 2003;6:443-448.
- Of the 62 patients who had the IDET procedure, 51 (82%) were available for follow-up a minimum of 24 months later. Statistically significant improvements were reported in low back visual numeric pain scale (VNS), Roland Morris disability evaluation (RM), and lower extremity (LE) pain scores (P<0.001).
- 53% of patients (27/ 51) had clinically significant improvements in VNS and RM.
- 63% (32/51) said they would undergo same procedure again for same result.
- Seven patients (14%) underwent additional therapeutic procedures during follow-up; only 2 had spinal fusion.
- No complications of dural puncture, infection, or nerve injury were reported.