Reply to reply: Radiofrequency neurotomy for spinal pain

Reply to the answer by Niemistö et al to our letter to the editor

MicheleCuratolo,M.D.,Ph.D.a

Sebastian Reiz, M.D., Ph.D.b

aDepartment of Anesthesiology, Division of Pain Therapy,
University Hospital of Bern, Inselspital, Switzerland.

bCentre Anti-Douleurs, Clinique de Montchoisi, Lausanne, Switzerland.

Corresponding author:

MicheleCuratolo,M.D.,Ph.D.

Department of Anesthesiology

Division of Pain Therapy

Inselspital, 3010 Bern

Switzerland

Phone:+41-31-632 30 27

Fax:+41-31-632 30 28

Email:

We thank Dr Niemistö and colleagues for their reply to our letter concerning their article.1 While we agree with several of their statements, we regret that they have not addressed our principal objection to their publication: that there is only one randomized controlled trials (RCT) published in the literature that merits inclusion in a systematic review of radiofrequency (RF) neurotomy.2 All other studies had important flaws, either in their patient selection criteria, or in their operative techniques, or both. An editorial3 accompanying a recent negative article on RF neuromy4 clearly illustrates this issue.

Furthermore, we find it strange that Niemistö et al still consider the work by Barendse et at5 on intradiscal RF as a "clinically relevant trial indication". They mention modifications of innervation in disc degeneration as a reason for a possible effect of RF in discogenic pain.6 Because the RF lesion is localized at the active tip of the electrode,7 a RF lesion placed in the nucleous pulposus can never be successful in discogenic pain, even when the article cited by Niemistö et al is considered for explaining the innervation of the disc.6 Furthemore, unlike internal disc disrupture, there is no evidence that disc degeneration is an independent cause of low back pain.8

The above considerations confirm our main criticisms on the way Niemistö et al performed their review: a) although they correctly applied the general principles of how to conduct a systematic review, they did not have a sufficient background knowledge on the issue that they reviewed; b) they did not check two essential qualities of the RCT included in their analysis, i.e. whether patients’ pain was due to the pathology for which they were included and whether the treatment that was tested was performed correctly.

References

1.Niemisto L, Kalso E, Malmivaara A, et al. Radiofrequency denervation for neck and back pain: a systematic review within the framework of the cochrane collaboration back review group. Spine 2003;28:1877-88.

2.Lord SM, Barnsley L, Wallis BJ, et al. Percutaneous radio-frequency neurotomy for chronic cervical zygapophyseal-joint pain. N Engl J Med 1996;335:1721-6.

3.Bogduk N. Cervicogenic headache. Cephalalgia 2004;24:819-20.

4.Stovner L, Kolstad F, Helde G. Radiofrequency denervation of facet joints C2-C6 in cervicogenic headache: A randomized, double-blind, sham-controlled study. Cephalalgia 2004;24:821-30.

5.Barendse GA, van Den Berg SG, Kessels AH, et al. Randomized controlled trial of percutaneous intradiscal radiofrequency thermocoagulation for chronic discogenic back pain: lack of effect from a 90-second 70 C lesion. Spine 2001;26:287-92.

6.Freemont AJ, Peacock TE, Goupille P, et al. Nerve ingrowth into diseased intervertebral disc in chronic back pain. Lancet 1997;350:178-81.

7.Bogduk N, Macintosh J, Marsland A. Technical limitations to the efficacy of radiofrequency neurotomy for spinal pain. Neurosurgery 1987;20:529-35.

8.Moneta GB, Videman T, Kaivanto K, et al. Reported pain during lumbar discography as a function of anular ruptures and disc degeneration. A re-analysis of 833 discograms. Spine 1994;19:1968-74.

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