MBB vs ESI

[PMR 4 MSK]

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66 y/o female diabetic with primarily extension-based back pain, radiating into buttocks, xrays showed DDD L2 through S1, with signficant facet arthropathy, PE most c/w facet-mediated pain. I did MBB on the right x 2, both with near-100% pain relief, did RFA, right side is perfect.

So I do left MBB's and they don't help at all, pain is worse after on the left. I get an MRI and it shows very severe stenosis L4-5 and L3-4, moderate stenosis L2-3, bad DDD all levels and bad facets everywhere, no acute process.

I'd like to do ESI, but the steroids used for RFA and a previous shoulder injection have both shot her blood sugars in to the 400's for more than 2 weeks, despite intensive intervention by her PCP. (We only have 1 endocrinologist around here and he usually doesn't see diabetics.)

A few questions:

Would you do ESI in this patient?

How do you account for MBB + RFA working so well on one side, but making the other worse?

Also, do you require MRI prior to facet procedures? I usually have one, but have never required it if I was pretty sure the facets were the cause of the pain.

Other thoughts on this pt?

 

[Mister Mxyzptlk]

They are allowed to have more than one pain problem, and as I'm sure you have seen many times the relief of one problem seems to bring the next one in line to the forefront.

I don't get MRIs when I suspect mechanical pain. If my treatment for mechanical pain doesn't work then I start imaging.

I would try an ESI with maybe 1/4 the usual dose. Nobody knows what the effective dose is anyway, and some studies suggest they aren't even needed because what you really do is wash out all those chemicals that I can never remember.

Speaking of which, why don't we try epidural lavage? Admit them to the hospital for a week with NS running through an epidural catheter.

 

[Tenesma]

1) you give steroids with RFA? maybe it wasn't the RF that helped but rather the steroid?

2) easy solution: mix your steroid with insulin when you inject...

3) just kidding - no more steroids for her for a few months, and then in the future use very low doses of steroids (and stick w/ triamcinolone - anecdotally i have had less sugar probs w/ my super-sensitive diabetics)

4) get her into PT/chiro/acupuncture and have her f/u in 2 months

 

[SSdoc33]

66 y/o female diabetic with primarily extension-based back pain, radiating into buttocks, xrays showed DDD L2 through S1, with signficant facet arthropathy, PE most c/w facet-mediated pain. I did MBB on the right x 2, both with near-100% pain relief, did RFA, right side is perfect.

So I do left MBB's and they don't help at all, pain is worse after on the left. I get an MRI and it shows very severe stenosis L4-5 and L3-4, moderate stenosis L2-3, bad DDD all levels and bad facets everywhere, no acute process.

I'd like to do ESI, but the steroids used for RFA and a previous shoulder injection have both shot her blood sugars in to the 400's for more than 2 weeks, despite intensive intervention by her PCP. (We only have 1 endocrinologist around here and he usually doesn't see diabetics.)

A few questions:

Would you do ESI in this patient?

How do you account for MBB + RFA working so well on one side, but making the other worse?

Also, do you require MRI prior to facet procedures? I usually have one, but have never required it if I was pretty sure the facets were the cause of the pain.

Other thoughts on this pt?

you bring up a very interesting issue and one that nobody seems to want to talk about. when you RF, you denervate the corresponding multifidi. they dont just sit there. they are short rotators and stabilizers and contribute a big part of your core musculature. it is entirely possible that the lack of dynamic stability and movement on one side stressed the other, so that they are now "more painful". it is also possible that the left side always was painful, and she is now just noticing/complaining about it more now. i have always wondered about this, but havent seen anyting in the literature on it. i made the mistake of asking bogduk about it at a question and answer session and, to put it nicely, i wont be doing that again. he didnt give me an answer, however......

 

[PMR 4 MSK]

1) you give steroids with RFA? maybe it wasn't the RF that helped but rather the steroid?

I was taught to give 10 - 20 mg depomedrol or equivalent as a chaser after each burn to reduce post-RFA flare of pain. The nurses tell me most the guys in my area do this to one degree or another. One guy gives 80 mg/level, but he also routinely gives people 320 mg or more in an ESI

 

[Tenesma]

i don't think it is unreasonable - look at the japanese literature...

but i would argue that you could probably get away with a far lower dose than 10-20mg/level --- i would also argue that you will never truly know if it was the RF or the steroid that was successful for pain control...

 

[ampaphb]

i would also argue that you will never truly know if it was the RF or the steroid that was successful for pain control...

Do you add a little dab of steroid to your MBBs in the belief that it can provide long term relief? I don't envision this procedure as anything other than diagnostic, so I don't.

 

[spondy14]

you bring up a very interesting issue and one that nobody seems to want to talk about. when you RF, you denervate the corresponding multifidi. they dont just sit there. they are short rotators and stabilizers and contribute a big part of your core musculature. it is entirely possible that the lack of dynamic stability and movement on one side stressed the other, so that they are now "more painful". it is also possible that the left side always was painful, and she is now just noticing/complaining about it more now. i have always wondered about this, but havent seen anyting in the literature on it. i made the mistake of asking bogduk about it at a question and answer session and, to put it nicely, i wont be doing that again. he didnt give me an answer, however......

R U saying that bogduk has a problem with RF?

 

[Mister Mxyzptlk]

This question arises from time to time but I have never heard an answer either way and I don't know how you could ever measure it.

 

[Tenesma]

my lumbar MBB is 0.3ml of lido 1% via a tuberculin syringe (more accurate) with NO steroid...

the use of steroids for RF is debatable depending on which literature you read - some believe it decreases bone inflammation/neuritis pain...

 

[Ligament]

my lumbar MBB is 0.3ml of lido 1% via a tuberculin syringe (more accurate) with NO steroid...

the use of steroids for RF is debatable depending on which literature you read - some believe it decreases bone inflammation/neuritis pain...

Has anybody studied the volume of LA required to cover the medial branches? Where does the typical .3-.5cc come from? Unless you are right on the nerve, you wont get a block. You cant tell for sure whether you are right on a nerve unless you do motor stim and get multifidi contraction. If you cant get multifidi contraction due to atrophy, age, or post surgical status then you cant really be certain that you are on the nerve, for sure. I know the anatomical studies show "typical" courses of the medial branches but there are always variations.

 

[Tenesma]

for me it comes from injecting small volumes of contrast - i moved to 0.3ml after noticing that 0.5ml of contrast went EVERYWHERE.

as far as muscle stim goes - the muscle will contract just by having the needle in the muscle body itself, so muscle contraction does not necessarily ALWAYS imply that you are on the right target...

 

[mille125]

my lumbar MBB is 0.3ml of lido 1% via a tuberculin syringe (more accurate) with NO steroid...

the use of steroids for RF is debatable depending on which literature you read - some believe it decreases bone inflammation/neuritis pain...

you have obviously never had a patient with bad neuritis post rf...get one of these and it will change your practice

 

[Tenesma]

the incidence of neuritis based on a few retrospective studies is about 1%... which usually resolves within about 2 weeks... it is part of my consent for RFs.

during fellowship one of the attendings always would put 20mg per level that was RFed... so when the patient came back with return of pain after a month or two, I never was sure whether the RF failed or was it the steroids that wore off...

 

[lobelsteve]

the incidence of neuritis based on a few retrospective studies is about 1%... which usually resolves within about 2 weeks... it is part of my consent for RFs.

during fellowship one of the attendings always would put 20mg per level that was RFed... so when the patient came back with return of pain after a month or two, I never was sure whether the RF failed or was it the steroids that wore off...

That is the reported/published incidence of post RF neuritis. I guarantee the number is between 5-10% (of course this could not be proven either way). I have had 10-15 cases of neuritis in the past 2 years. They have all resolved within 3 weeks, and I have treated it with Lyrica or Cymbalta samples. Neuritis happens- and I'm glad it is transient. But I don't want to be the guy publishing a case series on post-RF neuritis making the possibility of a few patients declining the procedure for fear of the outcome.

 

[mille125]

the incidence of neuritis based on a few retrospective studies is about 1%... which usually resolves within about 2 weeks... it is part of my consent for RFs.

during fellowship one of the attendings always would put 20mg per level that was RFed... so when the patient came back with return of pain after a month or two, I never was sure whether the RF failed or was it the steroids that wore off...

i agree with steve...i can guarantee you that neuritis is greater than 1%...patients compare it to the amount of discomfort that a post dural puncture patient has (also a few weeks)...why put patients through this if a little steroid can help prevent it...i had 3 cases of neuritis in 18 months without using steroid (i was simply during it the way that i was trained)...i have not had a case since using steroid....i put 40 mg in a tb syringe and inject .1 to .2 of steroid at each level........successful RF should not last 1-2 months (at least in my experience)...if your attending found this response, it was probably from the steroid...

 

[Tenesma]

agreed that a little dot of steroid seems to go a long way...

 

[Mister Mxyzptlk]

I don't use steroids for RF and never have. I do about 15-20 RF/month so I should be hearing complaints given the rates people are citing. I honestly can't remember when I saw the last episode of neuritis. It's probably been a couple of years. I have never seen the agonizing pain that people describe here and I am surprised to hear that it is such a big problem.

The few that I've seen all complained primarily of allodynia, and I treated that with EMLA cream and later Lidoderm when it came out.

FWIW here's how I do mine but I don't think there's anything magic here.

Neurotherm unit in office ,occasionally use Bayliss at facility

10-20-10 needle for lumbar, 5-20-5 or 10-20-5 cervical depending on neck size.

Infero-lateral approach, (sort of a "pillar view" approach but I don't actually do a pillar view, just enter one level below the target and head north with my needle)

Sensory (50 Hz) and motor (2 Hz) stim. I'm very fussy about getting good sensory stim. I will spend a long time fishing around for it if need be. A lot people don't use it but this recipe works for me.

0.5 cc 1% lidocaine

Single burn @ 80 C for 90 secs

 

[ampaphb]

I don't use steroids for RF and never have. I do about 15-20 RF/month so I should be hearing complaints given the rates people are citing. I honestly can't remember when I saw the last episode of neuritis. It's probably been a couple of years. I have never seen the agonizing pain that people describe here and I am surprised to hear that it is such a big problem.

The few that I've seen all complained primarily of allodynia, and I treated that with EMLA cream and later Lidoderm when it came out.

FWIW here's how I do mine but I don't think there's anything magic here.

Neurotherm unit in office ,occasionally use Bayliss at facility

10-20-10 needle for lumbar, 5-20-5 or 10-20-5 cervical depending on neck size.

Infero-lateral approach, (sort of a "pillar view" approach but I don't actually do a pillar view, just enter one level below the target and head north with my needle)

Sensory (50 Hz) and motor (2 Hz) stim. I'm very fussy about getting good sensory stim. I will spend a long time fishing around for it if need be. A lot people don't use it but this recipe works for me.

0.5 cc 1% lidocaine

Single burn @ 80 C for 90 secs

How far anterior on lateral view is your optimal position for the cannula tip?

 

[Mister Mxyzptlk]

I don't go very far anteriorly at all. I use a curved tip and run along the dorsum of the lamina, alternating between turning the tip anteriorly and 90 degrees laterally in order to advance it along the periosteum. I sort of wiggle my way across keeping in contact with bone all the time.

When I feel the superior edge of the lamina I back up a tiny bit and turn the curved tip anteriorly, trying to hang the tip over the edge of the lamina.

I'm sure this description is clear as mud. If I have time I'll try to draw a diagram or post some images but don't hold your breath. I have too many balls in the air right now.

I know that what I'm describing in this thread and the IR thread is heresy in terms of one only set of prognostic blocks, one burn, a different approach to positioning, etc, but it has evolved over the years and it works for me. I am not advocating that anyone else do it or even believe it.

When the insurance companies insist that I follow ODG and do two sets of MBBs I usually argue with them that it's not necessary to put the patient through two procedures. That's how strongly I feel about it - I'll put my money where my mouth is and argue my way out of the extra procedural fee.

The insurance companies then insist that I do double blocks. Talk about role reversal.

 

[Tenesma]

it is interesting when you talk to the RF gurus - they are doing less and less sensory stimulation (they consider it unreliable and a waste of tiem) and they focus on motor a lot more...

i find this to be especially true in post-surgical patients - i rarely get good sensory but frequently get motor response and the RFs turn out ok.

 

[ampaphb]

When the insurance companies insist that I follow ODG and do two sets of MBBs I usually argue with them that it's not necessary to put the patient through two procedures. That's how strongly I feel about it - I'll put my money where my mouth is and argue my way out of the extra procedural fee.

Aren't you arguing yourself into a procedure that reimburses at significantly higher level?

 

[lobelsteve]

it is interesting when you talk to the RF gurus - they are doing less and less sensory stimulation (they consider it unreliable and a waste of tiem) and they focus on motor a lot more...

i find this to be especially true in post-surgical patients - i rarely get good sensory but frequently get motor response and the RFs turn out ok.

I've noticed this as well. I do sensories, but if my threshold is not achieved at 0.3V with a Stryker, I don't care. I switch over to motor and get it before 0.5V and get could toaster wire cooking. I also like the ability to get down to lamina using 1% in tiny squirts to make the procedure less painful. A good reason I have trouble with the sensories.

 

[Mister Mxyzptlk]

Aren't you arguing yourself into a procedure that reimburses at significantly higher level?

Since I believe that the second block will not add anything to the decision-making, no.

 

[Tenesma]

i have 3 insurance companies now that are not allowing RF until i can document 2 diagnostic MBBs with greater than 80% relief....

so while i agree with gorback to a certain degree - and it is usually more on a case-by-case basis (ie: patient with frequent DVTs and a prosthetic aortic valve and hx of CVAs due to embolic events with back pain consistent with posterior element involvement - i would just hold the blood thinner - do ONE diagnostic MBB and then proceed with RF the next day)

but it looks like insurance is pushing us into this direction.

 

[ampaphb]

Since I believe that the second block will not add anything to the decision-making, no.

So when you did them, the results of the second MBBs were always identical with that of the first?

 

[Mister Mxyzptlk]

So when you did them, the results of the second MBBs were always identical with that of the first?

Identical is a difficult word. I found that the second block's results agreed enough that it did not change clinical decision-making.

I do not accept 50% relief, or even 80% relief (whatever "% relief" means - I have no idea and anyone who thinks they do is living in a fool's paradise). I expect complete relief or very close to it after MBB. I want to see them bend and twist and have a smile on their face because it feels so good.

I examine them preop, intra-op and immediately postop so I get a good sense of what's different and what isn't. If they still have pain I examine them very carefully for other painful areas. Did I miss a level? Is there SI joint pain confounding the response? If they still have axial pain in the anesthetized area is this discogenic?

I always used to do IA injections before trying RF. Such a high percentage subsequently went to RF that I just started skipping IA. Even when IA worked it needed repeating much sooner than RF.

In essence I have cut my income from potential procedural fees significantly by doing this, but I follow this pathway because I don't believe in doing unecessary or ineffective things to people. Over the years I've pared it down to where I can get people feeling better the fastest and least expensive way that I can.

Your mileage may vary.

 

[ampaphb]

Identical is a difficult word. I found that the second block's results agreed enough that it did not change clinical decision-making.

I do not accept 50% relief, or even 80% relief (whatever "% relief" means - I have no idea and anyone who thinks they do is living in a fool's paradise). I expect complete relief or very close to it after MBB. I want to see them bend and twist and have a smile on their face because it feels so good.

I examine them preop, intra-op and immediately postop so I get a good sense of what's different and what isn't. If they still have pain I examine them very carefully for other painful areas. Did I miss a level? Is there SI joint pain confounding the response? If they still have axial pain in the anesthetized area is this discogenic?

I always used to do IA injections before trying RF. Such a high percentage subsequently went to RF that I just started skipping IA. Even when IA worked it needed repeating much sooner than RF.

In essence I have cut my income from potential procedural fees significantly by doing this, but I follow this pathway because I don't believe in doing unecessary or ineffective things to people. Over the years I've pared it down to where I can get people feeling better the fastest and least expensive way that I can.

Your mileage may vary.

My population is clearly different from yours then. I have 10-15% of patients who get good, albeit short term relief from an initial IA injection, but then get inadequate or no relief from a confirmatory block (we belt and suspender them with MBB and pure steroid IA on the second visit). Correct me if I am wrong, but the false positives on the initial blocks I seem to have in my population would go directly on to RF based on your algorithm, no? Or am I misunderstanding?

 

[Mister Mxyzptlk]

My population is clearly different from yours then. I have 10-15% of patients who get good, albeit short term relief from an initial IA injection, but then get inadequate or no relief from a confirmatory block (we belt and suspender them with MBB and pure steroid IA on the second visit). Correct me if I am wrong, but the false positives on the initial blocks I seem to have in my population would go directly on to RF based on your algorithm, no? Or am I misunderstanding?

I don't think it's valid to try to extrapolate your false positives to my practice.

The current interpretation of the response to double blocks arises from the a priori assumption that if the blocks disagree then the positive response is wrong. What cosmic law says that is the case?

If one blocks works and one fails, why would you assume that the one that worked was wrong? Perhaps on one day the SI joints hurt too so the patient reported no relief, but the second time the SI joints weren't hurting so bad and the results were very good. Or maybe laying on the table for the first set provoked SI pain that was subsequently present at the second procedure. Or maybe you just did a lousy job on the negative block and it was operator error.

The man with one watch always knows what time it is but the man with two watches is never sure.

Maybe we should do a third tie-breaker block, or perhaps 25 blocks.

 

[lobelsteve]

I don't think it's valid to try to extrapolate your false positives to my practice.


Maybe we should do a third tie-breaker block, or perhaps 25 blocks.

Block #1 1% lidocaine
Block #2 0.5% Marcaine
Block #3 Hot fudge*




* Hot fudge in excess of 65 degrees C can cause neurolysis at which point the block becomes therapeutic and no longer diagnostic. Additionally, hot fudge prepared in any method other than a double boiler can impart a strong glucose effect causing a chemical neurolysis. In order to use the hot fudge technique appropriately and competently in medial branch blockade, only unsweetened or bittersweet chocolate may be used. It needs to be appropriately tempered and allowed to cool to 40 degrees C prior to injection. I will be offering course work and certification in HF3MBB techniques as part of membership in the SLAPPED ASS. (see prior post- http://forums.studentdoctor.net/showthread.php?t=532263&highlight=slapped )

 

[Mister Mxyzptlk]

Steve, please do not interrupt Peter when he's in the middle of taking my deposition. 😉

 

[mille125]

i have 3 insurance companies now that are not allowing RF until i can document 2 diagnostic MBBs with greater than 80% relief....

so while i agree with gorback to a certain degree - and it is usually more on a case-by-case basis (ie: patient with frequent DVTs and a prosthetic aortic valve and hx of CVAs due to embolic events with back pain consistent with posterior element involvement - i would just hold the blood thinner - do ONE diagnostic MBB and then proceed with RF the next day)

but it looks like insurance is pushing us into this direction.

this is quite comical...two diagnositic MBB's will actually cost more than the RF.......but why am i surprised....we are talking about insurance companies

 

[Mister Mxyzptlk]

this is quite comical...two diagnositic MBB's will actually cost more than the RF.......but why am i surprised....we are talking about insurance companies

I have often wondered about this and I was going to try to do the calculations. What is the cost of double blocks vs the cost of proceeding to RF after just one set of blocks?

I did a cursory literature search on MBBs this morning and all of the ones I read were retrospective, and some reported false positive rates of almost 50%!

Can anyone direct me to a prospective (preferably RCT) study?

 

[PMR 4 MSK]

Every so often I get someone with a paradoxical response to MBB. Had a guy in last week, injected him under fluoro, .3 ml 1% lido to each MB. Immediately post-procedure pain was worse - pt had difficulty sitting or changing positions, which subsided within a 1/2 hour to baseline pain with no improvement over baseline by D/C home. I assume that was muscle spasm from the 5" needle I had to bury in him to get to the nerves (big guy).

Today he tells me the pain has been getting better every day since about 2 days post-injection and is now 70% better. 😕 Not sure how someone gets better days later from a lidocaine injection. In patients like this, I've tried just doing the same basic procedure as a TPI sans fluoro, but with no response. Placebo? Magical needle? Shearing of the MB nerve? Bleeding causing prolotherapy?

So what would you be able to say if you repeated this injection? He's better now, so not worth injecting right now, but if the pain returned and I blocked him again, and he got the same delayed response, I can't imagine RF'ing him. If he got immediate relief from the second one, but the first was disconcordant like this, do you RF?

 

[Mister Mxyzptlk]

I had one like that yesterday. I think it's related to being prone, which is not a good position for a lot people with back pain. The patient reported worse pain after the procedure. The area I blocked didn't hurt on palpation, but a new area above it did.

This is one of the problems I have with MBB research. If there isn't a good exam done immediately postop and you go on the patient's subsequent report at followup you will have false negatives if they had other painful areas - either pre-existing or induced by positioning on the table. I think it's imperative to get a good baseline exam before the procedure and then repeat it afterward.

Your patient probably feels better because once he got over the acute pain the MBBs helped. I see a lot of people who report a week or two of relief after MBBs. I attribute that to interrupting the pain/spasm cycle. I am not seeing long-term relief like they are reporting out of Paducah.

 

[ampaphb]

I have often wondered about this and I was going to try to do the calculations. What is the cost of double blocks vs the cost of proceeding to RF after just one set of blocks?

I did a cursory literature search on MBBs this morning and all of the ones I read were retrospective, and some reported false positive rates of almost 50%!

Can anyone direct me to a prospective (preferably RCT) study?

Dreyfuss P, Halbrook B, Pauza K, Joshi A, McLarty J, Bogduk N.
Efficacy and validity of radiofrequency neurotomy for chronic lumbar zygapophysial joint pain.
Spine. 2000 May 15;25(10):1270-7.

Equally importantly

Schwarzer AC, Aprill CN, Derby R, Fortin J, Kine G, Bogduk N.
The false-positive rate of uncontrolled diagnostic blocks of the lumbar zygapophysial joints.
Pain 1994;58:195–200.

found a 38% false positive rate. (the aforementioned Dreyfuss article had 7/22 false positives, or 32%)

Manchikanti L, Boswell MV, Singh V, et al.
Prevalence of facet joint pain in chronic spinal pain of cervical, thoracic, and lumbar regions.
BMC Musculoskelet Disorders website, May 28, 2004.

found their false-positive rates were 63% for the cervical spine, 55% for the thoracic spine, and 27% for the lumbar spine.

van Wijk RM, Geurts JW, Wynne HJ, Hammink E, Buskens E, Lousberg R, Knape JT, Groen GJ.
Radiofrequency denervation of lumbar facet joints in the treatment of chronic low back pain: a randomized, double-blind, sham lesion-controlled trial.
Clin J Pain. 2005 Jul-Aug;21(4):335-44. Erratum in: Clin J Pain. 2005 Sep-Oct;21(5):462.

demonstrated "no difference between radiofrequency and sham" with a single block paradigm, "although in both groups, significant VAS improvement occurred."

Bogduk, in a subsequent letter (Clin J Pain. 2006 May;22(4):409), suggested "The conclusion that matches the data of van Wijk et al is that lumbar RF medial branch neurotomy as practiced in The Netherlands does not work." He went on top say "Apart from not selecting patients on the basis of double-blind, controlled, diagnostic blocks, The Netherlands practice uses a discredited technique for denervation."

Michael Gofeld, in a letter in the same volume (Clin J Pain. 2006 May;22(4):410-1), wrote "Uncontrolled single block, applied for partially selected patients, yields 27% false-positive results. The excuse of "common practice" as a reason not to perform double blocks may be related to the authors' practice only. Moreover, the claim of superfluous nature of controlled blocks is not only light-minded but also potentially dangerous. By means of this "recommendation" one could apply an unnecessary radiofrequency procedure for every third patient, which certainly would result in patient dissatisfaction, breach of trust, and waste of time, not to mention monetary cost.

A concern was raised about needing a best two out of three injections.

Kaplan M, Dreyfuss P, Halbrook B, Bogduk N.
The ability of lumbar medial branch blocks to anesthetize
the zygapophysial joint: A physiologic challenge.
Spine 1998;23:1847–52.

documented a false negative rate of 11%. The Schwarzer article cited above estimated it at <5%.

 

[Mister Mxyzptlk]

I have not had time to read the entire text of these articles. The abstracts, however, all seem to show the same faulty assumption: the first block was automatically assumed to be a false-positive if the subsequent block, using a different drug, was negative.

All you really know is that they didn't agree, not why they didn't agree. I will have to tweak Nik about this. He is usually very unforgiving when others make assumptions not in evidence.

The first Dreyfuss paper appears to be about RF, not the validity of MBBs.

 

[ampaphb]

The first Dreyfuss paper appears to be about RF, not the validity of MBBs.

I thought we had already agreed that, other than in Paducah, MBBs are generally diagnostic tools. That being the case, they are included in the inclusion/exclusion criteria for an RCT regarding RF.

Dreyfuss's openng paragraphs state:

The prevalence of chronic lumbar zygapophysial joint pain ranges from 15% in younger patients to as high as 40% among elderly patients. The only proven treatment for this source of back pain is radiofrequency medial branch neurotomy. This operation is not a placebo. Van Kleef et al showed clearly, under double-blind controlled conditions, that patients treated with sham lesions did not obtain relief of pain. However, in patients treated with active neurotomy, Van Kleef et al obtained only modest results. The mean pain scores of their patientsdecreased only slightly, from 5 on a 10-point scale to 3. A minority of their patients obtained complete pain relief.

The rationale of lumbar medial neurotomy is that patients with zygapophysial joint pain should obtain complete relief of their pain if the nerves that innervate the painful joint are coagulated. The failure of Van Kleef et al to secure this outcome consistently can be attributed to either of two factors: First, they selected their patients on the basis of single, diagnostic blocks, whereas controlled studies have shown that single blocks carry a false-positive rate of 38%. Therefore, patients without true zygapophysial joint pain may have been treated.

Second, they placed the electrodes at an angle to the target nerve, whereas laboratory studies have shown that the electrode must lie parallel to the nerve if the nerve is to be maximally and optimally coagulated. Consequently, in some of their patients, Van Kleef et al may have failed to coagulate the target nerve adequately. In their study, adequate coagulation of the target nerves was not assessed with segmental electromyography of the multifidus.

The current study was undertaken to document the efficacy of lumbar medial branch neurotomy under optimal conditions. Patients were selected on the basis of controlled diagnostic blocks to ensure that they had zygapophysial joint pain, and electrodes were placed meticulously to optimize coagulation of the target nerve. Furthermore, measures were taken to ensure that the nerve was indeed coagulated. The anatomy of the medial branches of the lumbar dorsal rami is such that each supplies a unique and accessible band of the multifidus muscle. Consequently, if the nerve is successfully coagulated, its respective band of multifidus should show signs of denervation. Accordingly, postoperative electromyography was performed to check for successful coagulation of the target nerves.
​

 

[ampaphb]

I have not had time to read the entire text of these articles. The abstracts, however, all seem to show the same faulty assumption: the first block was automatically assumed to be a false-positive if the subsequent block, using a different drug, was negative.

All you really know is that they didn't agree, not why they didn't agree. I will have to tweak Nik about this. He is usually very unforgiving when others make assumptions not in evidence.

The first Dreyfuss paper appears to be about RF, not the validity of MBBs.

Best two out of three does seem as though it would be optimal.

I am not aware of any data, other than the personal experience of practitioners, that support the one confirmatory block is as good as two theory you propose. Can anyone direct me to a prospective (preferably RCT) study? 🙂

 

[Mister Mxyzptlk]

The Dreyfuss paper is not about the validity of MBBs. It is about the validity of RF. Discussion and data are two different things.

As an aside, the other Dreyfuss paper, although interesting, does not look at double blocks. The technique of using capsular distension is intriguing though, but assumes that capsular distention will always reproduce facet pain and/or that failure of MBBs to block same indicates false positive, also an assumption not in evidence.

I will just continue to make my patients happy and save them money with single blocks until someone can tell my why so many of my alleged false positives get pain relief for a year or so.

 

[ampaphb]

I will just continue to make my patients happy and save them money with single blocks.

While I will sleep well at night knowing that I will be destroying only those medial branches I can, with 90% confidence, say were actually the pain generator[FONT=Arial,Helvetica][FONT=Arial, Helvetica]. Not doing RF on those patients who don't need it will both save them money AND preserve their anatomy from an unnecessary destructive procedure.
..

 

[Mister Mxyzptlk]

You don't "know" that. You're probably bypassing people who really do have facet disease. You can't blindly accept the assumptions made in these flawed papers just because they're in print. All they show is that if you do two blocks they often disagree. They do not show why. Hence they cannot show that two blocks are better than one.

 

[ampaphb]

You are absolutely right - according to the published literature I am missing between 5-11% of patients and you are doing unnecessary RF's on 28% of patients. I prefer to err on the side of caution.

It makes no difference to me how established practitioners practice, but when we post on public forums like this, giving residents and fellows the green light re not following validated guidelines like those from ISIS, strikes me as unwise.

 

[Mister Mxyzptlk]

You are absolutely right - according to the published literature I am missing between 5-11% of patients and you are doing unnecessary RF's on 28% of patients. I prefer to err on the side of caution.

It makes no difference to me how established practitioners practice, but when we post on public forums like this, giving residents and fellows the green light re not following validated guidelines like those from ISIS, strikes me as unwise.

I'm just going repeat myself one more time and maybe the message will get through: You are too accepting of the printed word. A published paper isn't magical. It has no inherent validity. These papers, as with most papers published in pain management, suffer from terrible flaws either in design, statistical analysis, or conclusions - often all three.

Your appeal to authority regarding the ISIS Guidelines equally overstates their value and their validity. They are opinions based on interpretation of the literature by a very small group of people and those people are not without their own biases. There are other guidelines that disagree with ISIS. Indeed, many ISIS instructors do not follow ISIS Guidelines, which irritates some of the ISIS leadership no end because they teach non-ISIS techniques at the ISIS seminars.

Although I admire your self-appointed guardianship of the malleable minds of the residents and fellows, I feel compelled to warn them that most of what we "know" from the literature is plain and simple horse**** and to blindly follow it just because it's in print and a famous person endorses it in no way validates it.

In the past year I have reviewed three different topics for ISIS - nucleoplasty, adhesiolysis, and PRF. It feels a lot like what the cops must feel like when they have to sift through the garbage dump looking for evidence.

IMHO, the whole specialty needs to be torn down intellectually and rebuilt. Until then, we are not algologists, or algiatrists as AAPM has declared - we are merely anecdotalists.

Doctors must learn how to read critically. Learn how to analyze a paper. Don't just read the abstracts or accept something because someone famous said it.

 

[ampaphb]

I'm just going repeat myself one more time and maybe the message will get through: You are too accepting of the printed word. A published paper isn't magical. It has no inherent validity. These papers, as with most papers published in pain management, suffer from terrible flaws either in design, statistical analysis, or conclusions - often all three.

Your appeal to authority regarding the ISIS Guidelines equally overstates their value and their validity. They are opinions based on interpretation of the literature by a very small group of people and those people are not without their own biases. There are other guidelines that disagree with ISIS. Indeed, many ISIS instructors do not follow ISIS Guidelines, which irritates some of the ISIS leadership no end because they teach non-ISIS techniques at the ISIS seminars.

Although I admire your self-appointed guardianship of the malleable minds of the residents and fellows, I feel compelled to warn them that at most of what we "know" from the literature is plain and simple horse**** and to blindly follow it just because it's in print and a famous person endorses it in no way validates it.

In the past year I have reviewed three different topics for ISIS - nucleoplasty, adhesiolysis, and PRF. It is feels a lot like what the cops must feel like when they have to sift through the garbage dump looking for evidence.

IMHO, the whole specialty needs to be torn down intellectually and rebuilt. Until then, we are not algologists, or algiatrists as AAPM has declared - we are merely anecdotalists.

Doctors must learn how to read critically. Learn how to analyze a paper. Don't just read the abstracts or accept something because someone famous said it.

We have been down this road before, and I know your final refuge generally is the "appeal to authority" response when the literature disagrees with you. I prefer to think of it as being humble, and recognizing that mine is not the last word on any subject, and that I am not arrogant enough to think I can't learn from others' experience.

I too read the literature critically, and dismiss what I consider to be horse****. But unless you are willing to accept SOME literature (and the Dreyfuss RF article is a prime example of what I consider to be a first rate study), why would you bother to go to work in the first place? Or do you just do it because, in your opinion, it works, regardless if there is literature to back up what we do?

As for the "other guidelines", are you referring to the ACOEM or ODG guidelines, designed to enable insurance companies to not pay for anything we do? Or perhaps the ASSIP guidelines, written to enable us to do virtually anythig we please?

 

[Mister Mxyzptlk]

it is interesting when you talk to the RF gurus - they are doing less and less sensory stimulation (they consider it unreliable and a waste of tiem) and they focus on motor a lot more...

i find this to be especially true in post-surgical patients - i rarely get good sensory but frequently get motor response and the RFs turn out ok.

Are gurus exempted from following the literature? I ask because as a lesser being some would hold me to that standard when I jettison double blocks as a waste of time.

 

[Mister Mxyzptlk]

I too read the literature critically, and dismiss what I consider to be horse****.

I would like to hear your critical assessment of:

Schwarzer AC, Aprill CN, Derby R, Fortin J, Kine G, Bogduk N.
The false-positive rate of uncontrolled diagnostic blocks of the lumbar zygapophysial joints. Pain 1994;58:195–200.

 

[Tenesma]

well there is an interesting article by Cohen and Stojanovic where they argue that RF can be helpful for longer-term pain control even in those with only 50% relief w/ MBB... hmmm...

 

[ampaphb]

Are gurus exempted from following the literature? I ask because as a lesser being some would hold me to that standard when I jettison double blocks as a waste of time.

Given that the ISIS Guidelines do NOT recommend sensory stim, I hate to break it to you, but in this instance, you are not an iconoclast - you are just in with the rest of we mere mortals

 

[ampaphb]

I would like to hear your critical assessment of:

Schwarzer AC, Aprill CN, Derby R, Fortin J, Kine G, Bogduk N.
The false-positive rate of uncontrolled diagnostic blocks of the lumbar zygapophysial joints. Pain 1994;58:195–200.

Feel free to post your thoughts, and I will be happy to respond, but I feel no need to prove my ability to critically read literature.

Should you require an example of my propensity to rip bad science apart, please refer to my recent post on the PM&R board

Arch Phys Med Rehabil. 2008 Jun;89(6):1011-5.
The relationship between repeated epidural steroid injections and subsequent opioid use and lumbar surgery.
Friedly J, Nishio I, Bishop MJ, Maynard C.

OBJECTIVES: To evaluate whether the use of epidural steroid injections (ESIs) is associated with decreased subsequent opioid use in patients in the Department of Veteran's Affairs (VA) and to determine whether treatment with multiple injections are associated with decreased opioid use and lumbar surgery after ESIs.

DESIGN: VA patients undergoing ESIs during the study period for specific low back pain (LBP) diagnoses were identified, and lumbar surgery and opioid use were examined for 6 months before and after

ESI. SETTING: National VA administrative data.

PARTICIPANTS: U.S. veterans (retrospective data analysis).

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURES: Opioid use and lumbar surgery after ESIs.

RESULTS: During the 2-year study period, 13,741 different VA patients underwent an ESI for LBP. The majority of patients were using opioids before their ESIs (64%), as were the majority after their ESIs (67%). Of patients not on opioids before the ESIs, 38% were prescribed opioids afterward, whereas only 16% of people on opioids before the ESIs stopped using opioids afterward. Patients who received more than 3 injections were more likely than patients receiving fewer injections to start taking opioids after ESIs (19% vs 13%, P<.001) and to undergo lumbar surgery after ESIs (8.7% vs 6.3%, P=.003).

CONCLUSIONS: Opioid use did not decrease in the 6 months after ESIs. In this population, patients who received multiple injections were more likely to start taking opioids and to undergo lumbar surgery within the 6 months after treatment with ESIs. These findings are concerning because our data suggest that ESIs are not reducing opioid use in this VA population.
No no, it's much better than that -

1) It doesn't make clear, and therefore I am assuming, these were both blind and fluoroscopically guided epidurals

2) It doesn't distinguish between transforaminal, interlaminar, or caudal procedures

3) It compares >3 vs 3 or less, within a 2 year period, but does not discuss whether these were done in a series, or over time. One series of three which then needed an additional injection is thus lumped in the same category as patients that had one injection every six months

4) 35% of patients who were not on opioids pre-procedure received opioid prescriptions after - were these short term, post-procedure prescriptions, or were they chronic opioid users - they do not distinguish.

5) They measured those who d/c'd their opioid use, but did not look at whether opioid use was decreased, even if not discontinued.

6) If a patient got better after one or two injections, you would expect them to stop using opioids, right? You would expect that THEY would be the ones more likely to not need surgery, right? Not these guys - they expect that, if you needed more than three injections, you should reduce your opioid use, and so were surprised when that population was more likely to go onto surgery.

Admittedly, if you didn't get better after either one or a series of three injections, you would also probably need opiods or surgery, but to me, that just belies the basic problem of the premise of the study - the assumptions they made, definitions they used, and methods they chose to employ to answer their questions, were imprecise (I am being kind).

What is really interesting is that, despite what a mess this paper is, it was published. Now each time you get turned down for an ESI, this is yet another horrendously flawed study that is going to be included in ACOEM, ODG, etc, and you are going to have to take time to explain to the medical director of the insurance carrier why they should not pay attention to "peer reviewed literature". Better still, some genius is going to include this nonsense in a meta-analysis, and tell you that 30 out of 42 published articles on ESI's show they don't work (I am making those numbers up).

You can thank the Dr. Friedly, The PM&R Department at The University of Washington, the Archives, and the Academy for adding to both of those particular headaches.