DRG pulsed RF article

[Ligament]

http://www.painphysicianjournal.com/2008/march/2008;11;137-144.pdf

2008;11;137-144. Response to Pulsed and Continuous Radiofrequency Lesioning of the Dorsal Root Ganglion and Segmental Nerves in Patients with Chronic Lumbar Radicular Pain
Pilot Study
Thomas T. Simopoulos, MD, Jan Kraemer, MD, Jyotsna V. Nagda, MD, Musa Aner, MD, and Zahid H. Bajwa, MD

Objectives: We aimed to prospectively evaluate the response and safety of pulsed and continuous radiofrequecy lesioning of the dorsal root ganglion/segmental nerves in patients with chronic lumbosacral radicular pain.


Methods: Seventy-six patients with chronic lumbosacral radicular pain refractory to conventional therapy met the inclusion criteria and were randomly assigned to one of 2 types of treatment, pulsed radiofrequency lesioning of the dorsal root ganglion/segmental nerve or pulsed radiofrequency followed immediately by continuous radiofrequency. Patients were carefully evaluated for neurologic deficits and side effects. The response was evaluated at 2 months and was then tracked monthly. A Kaplan-Meier analysis was used to illustrate the probability of success over time and a Box-Whisker analysis was applied to determine the mean duration of a successful analgesic effect.


Results: Two months after undergoing radiofrequency treatment, 70% of the patients treated with pulsed radiofrequency and 82% treated with pulsed and continuous radiofrequency had a successful reduction in pain intensity. The average duration of successful analgesic response was 3.18 months (± 2.81) in the group treated with pulsed radiofrequency and 4.39 months (±3.50) in those patients treated with pulsed and continuous radiofrequency lesioning. A Kaplan-Meier analysis illustrated that in both treatment groups the chance of success approached 50% in each group at 3 months. The vast majority of patients had lost any beneficial effects by 8 months. There was no statistical difference between the 2 treatment groups. No side effects or neurological deficits were found in either group.


Conclusion: Pulsed mode radiofrequency of the dorsal root ganglion of segmental nerves appears to be a safe treatment for chronic lumbosacral radicular pain. A significant number of patients can derive at least a short-term benefit. The addition of heat via continuous radiofrequency does not offer a significant advantage. A randomized controlled trial is now required to determine the effectiveness of pulsed radiofrequency.

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[Rhizo]

I'm had some successes with PRF for lumbar radicular pain....and some failures. I've been using in patients who don't want to consider a SCS (and no luck with meds, ESI etc.)

I apologize if this has been discussed before...I know the party line is that it should be billed 64999, but is it really wrong to consider billing as a SNRB/transforaminal? Short of injecting steroid, and using an RF cannula instead of a spinal needle, the main difference is the additional action of PRF. It's alot closer to the technical aspects and risks than billing it as something its not, like a neurolytic procedure...

 

[Mister Mxyzptlk]

I like how the study was designed and executed except for the comparison of PRF to [PRF + CRF]. Is that the "burning" issue of the day? I want to know if it (1) works and (2) works better than ESI. How many of us are routinely doing RFTC of the DRG any more for radicular pain?

In the inclusion criteria they said the candidates had to have failed TFESI, which was tantalizing. It's tempting to infer that PRF might work where TFESI did not. I would have much preferred to see the effort spent to test PRF vs TFESI.

As always, I take exception to the averaging of VAS.

I was disappointed that the authors did not address why their results were at variance with those of Geurts et al (Lancet, 2003), whose randomized double-blinded study showed a 16% response rate for PRF (vs 25% for sham). Instead they focused on how their results agreed with findings from much lower-quality studies. It's also disappointing (but sadly not surprising) that the editors allowed them to get away with it.

Note that in their final conclusions they did not try to extend these results to say that PRF of the DRG is actually effective.

In terms of study design and analysis this paper is refreshing. I'm looking forward to seeing more papers from this group in the future if they can keep up this level of quality (and stop averaging things that can't be averaged).

 

[ampaphb]

I like how the study was designed and executed except for the comparison of PRF to [PRF + CRF]. Is that the "burning" issue of the day? I want to know if it (1) works and (2) works better than ESI. How many of us are routinely doing RFTC of the DRG any more for radicular pain?

In the inclusion criteria they said the candidates had to have failed TFESI, which was tantalizing. It's tempting to infer that PRF might work where TFESI did not. I would have much preferred to see the effort spent to test PRF vs TFESI.

As always, I take exception to the averaging of VAS.

I was disappointed that the authors did not address why their results were at variance with those of Geurts et al (Lancet, 2003), whose randomized double-blinded study showed a 16% response rate for PRF (vs 25% for sham). Instead they focused on how their results agreed with findings from much lower-quality studies. It's also disappointing (but sadly not surprising) that the editors allowed them to get away with it.

Note that in their final conclusions they did not try to extend these results to say that PRF of the DRG is actually effective.

In terms of study design and analysis this paper is refreshing. I'm looking forward to seeing more papers from this group in the future if they can keep up this level of quality (and stop averaging things that can't be averaged).

The Guerts study was heat (67C, not pulsed)

 

[Mister Mxyzptlk]

To clarify: The present study showed an 80% response rate with PRF + heat. Why are the results different vs heat alone? It would appear that they used a lower temperature. Nonetheless, they need to address the discrepancy because both PRF and PRF + RFTC (at lower temperature) were 4x as successful in this study as with Geurts using RFTC. I said PRF instead of RFTC referring to Geurtsin my previous post. Sorry for any confusion.

 

[ampaphb]

To clarify: The present study showed an 80% response rate with PRF + heat. Why are the results different vs heat alone? It would appear that they used a lower temperature. Nonetheless, they need to address the discrepancy because both PRF and PRF + RFTC (at lower temperature) were 4x as successful in this study as with Geurts using RFTC. I said PRF instead of RFTC referring to Geurtsin my previous post. Sorry for any confusion.

When you say RFTC, what do the initials stand for, and is that the same procedure described by Dreyfuss which he calls radiofrequency neurotomy?

 

[lobelsteve]

RFTC- Radio Frequency Thermo Coagulation ?
RFA- Radio Frequency Ablation
RFN- Radio Frequency Neurotomy
CTN- Cook The Nerve
BTSOOTN- Burn The Snot Out Of The Nerve


I think they are all the same.

 

[Mister Mxyzptlk]

10 points for Gryffindor.