Outcomes of workers' compensation claimants with low back pain undergoing intradiscal electrothermal therapy.
METHODS
Case series.


OBJECTIVE
To describe the outcomes of workers' compensation (WC) claimants who have had a lumbar intradiscal electrothermal therapy (IDET) procedure.


BACKGROUND
IDET was developed as a less invasive treatment alternative to fusion after failure of conservative treatment for discogenic low back pain (LBP). Initial IDET case series from single practices have reported improved pain, function, and return to work outcomes. Little is known about results when performed by a variety of providers or in WC populations.


METHODS
LBP cases that underwent IDET between December 1, 1998 and February 29, 2000 were identified from WC records. Data sources included hardcopy claim files, administrative medical billing data, and computerized claim file narrative reports. Outcomes included narcotic use 6 months or more after IDET, additional invasive treatment after IDET (low back injections or surgery), and improved work status 24 months after IDET.


RESULTS
One hundred forty-two cases from 23 states were identified, with 97 different providers performing the procedure. Mean duration of symptoms before IDET was 26 months. Mean follow-up duration after IDET was 22 months. Ninety-six (68%) of the cases did not meet one or more of the published inclusion criteria. Seventy-eight cases (55%) received at least two narcotic prescriptions 6 months or more after IDET. Fifty-three (37%) had at least one lumbar injection and 32 (23%) had lumbar surgery after IDET. A total of 55 (39%) were working at 24 months after IDET; of these, 28 (20%) were not working and 27 (19%) were working before IDET. Narcotic use after IDET was associated with narcotic use before IDET, the same provider performing discography and IDET (provider self-referral), and positive signs of radiculopathy (C = 0.80). Need for invasive lumbar procedures after IDET were associated with provider self-referral, narcotic use before IDET, and older age (C = 0.73). Continued work absence after IDET was associated with provider self-referral, male gender, litigation, narcotic use before IDET, and older age (C = 0.83). Conformance with published selection criteria for IDET was not associated with provider self-referral or outcomes, nor was duration before IDET associated with outcomes.


CONCLUSIONS
The procedure may be less effective when performed by a variety of providers than suggested by initial case series performed by single providers or practices in work-related LBP cases. Provider self-referral and narcotic use before IDET are significant risk factors for poor outcomes. Randomized controlled trials are needed to determine whether there is a subset of patients with discogenic back pain who derive substantial and sustained benefit from this procedure.
Webster
Barbara S
BS
Liberty Mutual Center for Disability Research, Hopkinton, MA 01748, USA. barbara.webster@libertymutual.com
Verma
Santosh
S
Pransky
Glenn S
GS
D000328:Adult; D015331:Cohort Studies; D004363:Drug Utilization; D004599:Electric Stimulation Therapy / Q000191:economics / Q000706:statistics & numerical data; D004564:Electrocoagulation / Q000009:adverse effects / Q000706:statistics & numerical data*; D004651:Employment / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006979:Hyperthermia, Induced / Q000191:economics / Q000706:statistics & numerical data; D007405:Intervertebral Disc Displacement / Q000601:surgery*; D016015:Logistic Models; D017116:Low Back Pain / Q000191:economics / Q000453:epidemiology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009294:Narcotics / Q000627:therapeutic use; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data*; D018579:Patient Selection; D015995:Prevalence; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014942:Workers' Compensation / Q000706:statistics & numerical data*
D009294:Narcotics