Introduction: Although several studies have reported on outcomes following heating of annular tears with a thermo-resistive catheter (SpineCATH), little data is available on the efficacy of thermal treatment with a flexible radiofrequency electrode (discTRODE). The aim of this prospective case-control study was to determine the efficacy of radiofrequency heating of painful annular tears in the lumbar spine.

Methods: After at least six months of conservative treatment, 46 patients were studied for the presence of single level painful annular tears with MRI and provocative discography. Thirty-one patients underwent heating of their annular tears with a flexible radiofrequency electrode placed across the posterior annulus. The remaining fifteen patients continued with conservative management and acted as a control group. At present, 22 patients have been studied at 18 months follow-up and the remainder including the control group for a minimum of one year. The Visual Analogue Scale (VAS), the Oswestry Disability Index (ODI) and the Medication Quantification Score (MQS) were obtained before and at three monthly intervals after treatment.

Results: VAS decreased significantly after the radio-frequency treatment, and this decrease persisted at 18 months follow-up. The VAS did not change over 18 months in untreated controls. The decrease in VAS was significantly greater in the treated patients than the controls. The ODI also decreased in treated patients but did not change in controls. The MQS did not change in either group over the 18-month follow-up period.

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