1
Accepted for publication in Regional Anesthesia and Pain Medicine
Diagnosis of Facet Joint Pain and Prediction of Success and Failure for Cervical Facet
Radiofrequency Denervation
To the Editor:
Cohen et al’s (1) comprehensive analysis of factors predicting success and failure for
cervical facet radiofrequency denervation and evaluation of multiple variables is extremely
informative for the interventional pain management community and advances the knowledge and
understanding of radiofrequency denervation. This article also elicits a healthy debate. They
concluded that the only clinical variable associated with success was paraspinal tenderness.
While all the findings corroborate with previous publications in the diagnosis of facet joint pain,
paraspinal tenderness was an anomalous finding. The ability of the clinical picture to
characterize pain from facet joints was evaluated in multiple studies and conflicting results were
shown with conclusions that the history, clinical features, and radiological features are of no
significance or assistance in making the diagnosis of facet joint pain with certainty (2).
Consequently, controlled local anesthetic blocks of the facet joint or its nerve supply are
routinely employed to diagnose facet joint pain. Further, to ensure accuracy and validity, these
blocks must be controlled and verified for the delivery of a local anesthetic agent and placebo
response.
Cohen et al (1) utilized single diagnostic block, and showed response in only
approximately 50% of the patients after cervical radiofrequency denervation. They also showed
no significant difference between patients judged to have with a diagnostic block of 50% relief
or 80% relief. The issues with these assertions are 1) placebo response was not excluded which is
present in approximately 32% of the patients, 2) paraspinal tenderness is found in most (almost
all) of the patients with high sensitivity, however with low specificity. In a study of the diagnosis
2
of lumbar facet joint pain with comparative controlled local anesthetic blocks no significant
difference was identified with paravertebral tenderness (3). Failure to exclude placebo
responders by Cohen et al (1) may have resulted in responsiveness in only 50% of the patients
with radiofrequency denervation, compared to a much higher diagnostic rate when controlled
comparative local anesthetic blocks are used with at least 80% relief (4). Based on this, with a
single block and utilizing 50% relief as the criterion standard, a large proportion of patients will
be undergoing radiofrequency denervation, which may ultimately increase the cost of healthcare
with exploding interventions which have been claimed to contribute to increasing healthcare
costs and decreasing physician reimbursement (5). The controlled evaluations have shown
cervical facet joint pain to range from 39% to 60% with false-positive rates of 27% to 63% with
a single block (2). Consequently, without controlled diagnostic blocks, prevalence may be
extremely high leading to the encountered low response or failure.
Finally, Cohen at al’s (1) descriptions may be appropriate and practical for settings
described–mainly academic and military settings. However, they may not be appropriate for
private practice settings of which insurers and numerous policies demand 80% or 100% pain
relief prior to denervation along with a requirement to perform controlled diagnostic blocks
either with placebo or controlled comparative local anesthetic blocks. Thus, while Cohen et al’s
(1) stimulating information is appreciated, the pitfalls of such practices in daily clinical practices
must be appreciated.
Laxmaiah Manchikanti, MD
Associate Clinical Professor of Anesthesiology and Perioperative Medicine
University of Louisville, Kentucky
3
Medical Director, Pain Management Center of Paducah
Paducah, Kentucky
2831 Lone Oak Road
Paducah, KY 42003
270-554-8373, ext. 101
E-mail: drlm@thepainmd.com
Vijay Singh, MD
Medical Director, Pain Diagnostics Associates
1601 Roosevelt Road
Niagara, WI 54151
E-mail: vs@wmpnet.net
REFERENCES
1.
Cohen SP, Bajwa ZH, Kraemer JJ, Dragovich A, Williams KA, Stream J, Sireci A,
McKnight G, Hurley RW. Factors predicting success and failure for cervical facet
radiofrequency denervation: A multi-center analysis. Reg Anesth Pain Med 2007;32:495503.
2.
Seghal N, Dunbar EE, Shah RV, Colson JD. Systematic review of diagnostic utility of
facet (zygapophysial) joint injections in chronic spinal pain: An update. Pain Physician
2007;10:213-228.
3.
Manchikanti L, Pampati V, Fellows B, Baha A. The inability of the clinical picture to
characterize pain from facet joints. Pain Physician 2000;3:158-166.
4
4.
Boswell MV, Colson JD, Sehgal N, Dunbar EE, Epter R. A systematic review of
therapeutic facet joint interventions in chronic spinal pain. Pain Physician 2007;10:229254.
5.
Manchikanti L, Giordano J. Physician payment 2008 for interventionalists: Current state
of health care policy. Pain Physician 2007; 10:607-626.