Study Design: Prospective study with a 2-year follow-up.

Background: Intradiscal electrothermal therapy (IDET) was developed as an intermediate stage between conservative measures (analgesia, physiotherapy and injections) and radical surgery (fusion and disc replacement) for the treatment of internal disc disruption (IDD). Recent reports have questioned the efficacy and safety of this treatment.

Objective: To assess the long-term outcome of patients with discogenic low back pain (≥ 6 months duration) treated with IDET who had previously failed to improve with nonoperative treatment

Methods: Forty patients with IDD determined by pre-operative provocative discography and MRI were treated with IDET. VAS pain scores, SF-36 scores, analgesic usage and sitting tolerance (mins) were collected pre-treatment and at 12 and 24 months. Subsequent treatments were recorded. The differences in the outcome scores were tested by Wilcoxon signed rank tests.

Results: Average age was 46 years (range 25–62 years) with 44% males and 56% females. No significant improvement was seen in pain intensity as measured by VAS and bodily pain SF-36 scores pre treatment and at 12 and 24 months post IDET. There were no significant differences in the remaining SF-36 subscales. Only 11% used less pain medication. Sitting tolerance improved between pre and 1-year post IDET, the difference was not significant. Eight (20%) patients underwent further surgery; 5 disc replacement and 3 fusions at 1-year post treatment.

Conclusion: The patients with IDD did not show any improvement at 1-year or 2-year post IDET. A significant proportion of patients required further surgery. We believe that the efficacy of IDET is doubtful.