INTRADISCAL ELECTROTHERMAL THERAPY–A PROSPECTIVE ANALYSIS OF 65 PATIENTS.

Abstract

Aim: To assess the outcome of patients with chronic discogenic lumbar back pain who underwent intradiscal electro thermal therapy (IDET).

Design: A prospective longitudinal study

Subjects: Patients undergoing IDET in our unit between April 2000 and October 2007 were included in the study after assessment with discography and diagnostic imaging. Discographic concordant symptoms with subsequent abolition with local anaesthetic led to inclusion in the study regardless of discogram volume.

Outcome Measures: Subjects were assessed preoperatively with VAS pain scores, SF36, demographic data and pain diagrams. Then were then reassessed postoperatively with the, VAS pain scores SF36, employment status and subjective outcome at 6, and 12 months.

Results: 83 patients were treated with IDET. We had a follow up rate of 75% leaving a cohort of 65 patients. Mean follow up 7.6 months.

Overall there was a mean improvement in pain VAS scores of 1.9 (p=0.0875).

SF36 scores showed minimal improvement in both physical and mental parameters and there was minimal improvement in subjective outcome in 55% of patients.

However it was observed that a small subgroup of patients (30%) aged less than 40 with low volume positive discography and single level disease mean pain VAS scores improved by 3.78 from 7.52 to 3.74. 72% of these patients reported a subjective improvement in symptoms and SF36 scores improved significantly compared to the overall group.

Further analysis also revealed that the use of pain diagrams when interpreted according to the principles of Mann et al was the predictive value.

Conclusions: Patient selection seems to be crucial in determining a successful outcome using IDET. We still perform this procedure on those patients aged less than 40 with single level disease, positive low volume discography, no facet joint arthritis and an organic pre procedure pain diagram.