Do epidurals alter EMGs?

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facetguy

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I have a patient who is scheduled to get a lumbar epidural and a lumbar/lower EMG in close proximity. Can an epidural alter EMG findings?

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I have a patient who is scheduled to get a lumbar epidural and a lumbar/lower EMG in close proximity. Can an epidural alter EMG findings?

No. But poorly trained techs can. So can lotion, edema, dry skin, neurometrx, submaximal stim, poor measurements, enclosed noise, residents, and non physiatrists, non- neurologists. And 1000 other things. If no weakness, sensory loss, and reduced reflex- then no acute denervation is likely. F wave is useless unless gbs is in the differential. And you patient will have an Adonai and demyelinating neuropathy affecting the incompetent electromyograher. My 2 cents. I order so few emg these days cause they aren't done like they used to be.
 
It's funny you mention demyelinating disorder, because her paresthesia is non-dermatomal and bilateral, and has been progressing proximally from the plantar surfaces to the knees over the last few weeks. Motor normal and no hyperreflexia. No diabetic issues, although her internist just ordered some add'l labs. Denies visual changes. She's involved in a work-comp situation, so I have only limited control over her care but I've been pushing for the EMG. I've had MS on my mind since she started describing her symptoms to me.

PS She is also seeing an ortho and a pain mgmt doc (anesth.) for the work-comp injuries.
 
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I thought you could see positive sharps and fibs in the paraspinals near the epidural site. Am i remembering that wrong. I agree though, it certainly wouldn't effect any other aspect of the test
 
Wc neurosis. Or her transverse myelitis is really taking it's time.
Neuro consult on private insurance if she is legit and concerned about this.
 
It's funny you mention demyelinating disorder, because her paresthesia is non-dermatomal and bilateral, and has been progressing proximally from the plantar surfaces to the knees over the last few weeks. Motor normal and no hyperreflexia. No diabetic issues, although her internist just ordered some add'l labs. Denies visual changes. She's involved in a work-comp situation, so I have only limited control over her care but I've been pushing for the EMG. I've had MS on my mind since she started describing her symptoms to me.

PS She is also seeing an ortho and a pain mgmt doc (anesth.) for the work-comp injuries.

MS will not show up on an EMG study. there will be essentially normal findings (sometimes there is some decreased muscle activation, but this is subtle and can easily be missed)
 
And you patient will have an Adonai and demyelinating neuropathy affecting the incompetent electromyograher.

you will have the jewish name of the lord? how do you treat THAT?!?!
 
MS will not show up on an EMG study. there will be essentially normal findings (sometimes there is some decreased muscle activation, but this is subtle and can easily be missed)

She does have a prior hx of lumbar disc herniation and radiculopathy. The EMG would only be to get current/comparative findings on this and assess for multilevel radiculopathies. In the absence of radicular findings, demyelinating would have to remain on the list.

I'm trying to get her to a neuro on her private insurance, but with the work-comp overlap it's a bit tricky.
 
She does have a prior hx of lumbar disc herniation and radiculopathy. The EMG would only be to get current/comparative findings on this and assess for multilevel radiculopathies. In the absence of radicular findings, demyelinating would have to remain on the list.

I'm trying to get her to a neuro on her private insurance, but with the work-comp overlap it's a bit tricky.

wait. what? you are not really making any sense here.

lets define things. radiculopathy = objective evidence of injury to the radicle. this means a finding of weakness on exam, decreased reflex, or previous EMG finding. it is not correct to call leg pain with evidence of a disc herniation a "radiculopathy".

now, "radicular findings" can mean anything. any pain, numbness, tingling, or weakness shooting down the leg may be "radicular" but not necessarily radiculopathy. a demyelinating process, therefore, may be radicular as well.

its not clear if your patinet has had a previous EMG.

"demyelinating" can be central or peripheral, and my point was that central CNS lesions (like MS) will be normal on an EMG.

im not trying to be high and mighty here, just making sure we are talking the same language.
 
wait. what? you are not really making any sense here.

lets define things. radiculopathy = objective evidence of injury to the radicle. this means a finding of weakness on exam, decreased reflex, or previous EMG finding. it is not correct to call leg pain with evidence of a disc herniation a "radiculopathy".

now, "radicular findings" can mean anything. any pain, numbness, tingling, or weakness shooting down the leg may be "radicular" but not necessarily radiculopathy. a demyelinating process, therefore, may be radicular as well.

its not clear if your patinet has had a previous EMG.

"demyelinating" can be central or peripheral, and my point was that central CNS lesions (like MS) will be normal on an EMG.

im not trying to be high and mighty here, just making sure we are talking the same language.

Sorry for being vague. This patient is a 50 year old female with a recent work-comp related back injury (actually it was a fall, and there are bilateral wrist and left shoulder injuries as well), for which she is under the care of a WC-appointed ortho and pain mgmt doc. I've been treating her on/off for years for neck and back pain. Prior hx includes two MVAs, multilevel cervical disc herniations, EMG + cervical radiculopathy, at least one lumbar disc herniation (L3-4 as I recall, going from memory right now), and I believe a + EMG for lumbar radic.

So now she falls a few months ago at work and, among other things, she has recently been complaining of the paresthesia I described in my prior post: had begun distally at the plantar surface bilaterally, described as a "cold, wet" sensation, non-dermatomal. Over the last few weeks, per her description, this paresthesia has been creeping proximally and is now at about the knee level bilaterally. No motor or reflex abnormalities.

Pain doc wants to do a lumbar epidural, which is why I asked if an epidural would alter an EMG if she were to undergo an EMG shortly afterward. I don't think the EMG will be particularly helpful, but given her past hx may shed some light on the status on her lumbar spine. As noted earlier, I'm trying to get her to a neurologist because of the distribution of the paresthesia, which just seems weird to me (yes, it is work comp but I don't think she's fakin' it; never know though).
 
Sorry for being vague. This patient is a 50 year old female with a recent work-comp related back injury (actually it was a fall, and there are bilateral wrist and left shoulder injuries as well), for which she is under the care of a WC-appointed ortho and pain mgmt doc. I've been treating her on/off for years for neck and back pain. Prior hx includes two MVAs, multilevel cervical disc herniations, EMG + cervical radiculopathy, at least one lumbar disc herniation (L3-4 as I recall, going from memory right now), and I believe a + EMG for lumbar radic.

So now she falls a few months ago at work and, among other things, she has recently been complaining of the paresthesia I described in my prior post: had begun distally at the plantar surface bilaterally, described as a "cold, wet" sensation, non-dermatomal. Over the last few weeks, per her description, this paresthesia has been creeping proximally and is now at about the knee level bilaterally. No motor or reflex abnormalities.

Pain doc wants to do a lumbar epidural, which is why I asked if an epidural would alter an EMG if she were to undergo an EMG shortly afterward. I don't think the EMG will be particularly helpful, but given her past hx may shed some light on the status on her lumbar spine. As noted earlier, I'm trying to get her to a neurologist because of the distribution of the paresthesia, which just seems weird to me (yes, it is work comp but I don't think she's fakin' it; never know though).

Multiple injured body parts from a single fall at work + pre-existing multi-area chronic pain + multiple MVAs = dreadful patient. I have several of these. They are never, ever, ever any better, and in the rare chance one body part gets better after a series of treatments over many months, another will take over as the main pain and disabler. Their entire lives are wrapped up in their injuries. That and the lawsuits.
 
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Uggh...I have to jump in here, because this thread is fraught with incorrect statements, and this forum has repeatedly knocked non-anesthesiology-trained pain physicians, most recently by an anesthesia-trained pain fellow.

I don't know how many times I've had anesthesiology-trained pain fellows and attendings make annoying comments about how they are so advantaged doing procedures because they did epidurals all throughout their training, yada yada...

Just as annoying is the fact that so many of the same idiots have no clue how to perform a neuro exam, read an MRI or understand the purpose of EMG/NCS.

For clarification:
MS is NOT a peripheral nerve problem, it implicates oligodendroglia (CNS), not schwann cells (PNS).

EMG's don't diagnose central disorders.

Acute, ascending, bilaterally symmetric sensory dysfunction begs an urgent EMG and LP.

Demyelinating disorders of the peripheral nervous system? AIDP, CIDP, MMN, anti-sulfatide, anti-GM2, POEMS, amyloid, DM2, MGUS, monoclonal gammopathies, cryoglobulinemia, multiple myeloma, waldenstrom's, glycogen storage diseases, paraneoplastic (anti-Hu, anti-MAG), etc. to name a few...

The other day, in an attempt to teach a senior anesthesia resident the importance of a good neuro exam, I described a garden variety case of an older patient who over 6 months gradually developed neck pain (no arm symptoms), progressively worsening bilateral lower extremity weakness, spasticity, proprioceptive loss, hyperreflexia, clonus and babinski signs, with a wide-based ataxic gait (just to make things more obvious). I asked her where the lesion was...she said "Parkinson's"? Wow...really? There are so many things wrong with that answer I don't know where to begin. Sadly enough, even radiology residents/fellows would question why a cervical MRI was ordered since "it just couldn't be a cervical cord lesion because they had no arm symptoms", and would further schedule a lumbar MRI instead... worthless.

We all have our skillsets, and we all are idiots in fields that we're not trained in.
 
Uggh...I have to jump in here, because this thread is fraught with incorrect statements, and this forum has repeatedly knocked non-anesthesiology-trained pain physicians, most recently by an anesthesia-trained pain fellow.

I don't know how many times I've had anesthesiology-trained pain fellows and attendings make annoying comments about how they are so advantaged doing procedures because they did epidurals all throughout their training, yada yada...

Just as annoying is the fact that so many of the same idiots have no clue how to perform a neuro exam, read an MRI or understand the purpose of EMG/NCS.

For clarification:
MS is NOT a peripheral nerve problem, it implicates oligodendroglia (CNS), not schwann cells (PNS).

EMG's don't diagnose central disorders.

Acute, ascending, bilaterally symmetric sensory dysfunction begs an urgent EMG and LP.

Demyelinating disorders of the peripheral nervous system? AIDP, CIDP, MMN, anti-sulfatide, anti-GM2, POEMS, amyloid, DM2, MGUS, monoclonal gammopathies, cryoglobulinemia, multiple myeloma, waldenstrom's, glycogen storage diseases, paraneoplastic (anti-Hu, anti-MAG), etc. to name a few...

The other day, in an attempt to teach a senior anesthesia resident the importance of a good neuro exam, I described a garden variety case of an older patient who over 6 months gradually developed neck pain (no arm symptoms), progressively worsening bilateral lower extremity weakness, spasticity, proprioceptive loss, hyperreflexia, clonus and babinski signs, with a wide-based ataxic gait (just to make things more obvious). I asked her where the lesion was...she said "Parkinson's"? Wow...really? There are so many things wrong with that answer I don't know where to begin. Sadly enough, even radiology residents/fellows would question why a cervical MRI was ordered since "it just couldn't be a cervical cord lesion because they had no arm symptoms", and would further schedule a lumbar MRI instead... worthless.

We all have our skillsets, and we all are idiots in fields that we're not trained in.

Larry I like your style... a man after my own heart
 
he is a question then, if these fellowships are suppose to be multi-discliplinary, and the big bad anesthesia doctors are forced to train all the PMR, neurology folks these procedures, etc., then how come the PMR and neurology guys dont teach anesthesia folks how to do EMGs?

seems fair that we should teach everyone everything, right? If EMGs are part of pain management (at least PMR and neurology folks will say they are) then shouldnt this be taught to those that didnt train primarily in these fields?

im mainly playing devils advocate here, as i could give a **** about EMGs as i believe they basically worthless and overutilized for "pain" issues. They are definitly helpful in some neurological issues, but when i hear of someone doing an EMG on a 30 year old with 3 weeks of pain in the low back and the posterior leg with a huge L5-S1 disc, it seems silly.
 
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he is a question then, if these fellowships are suppose to be multi-discliplinary, and the big bad anesthesia doctors are forced to train all the PMR, neurology folks these procedures, etc., then how come the PMR and neurology guys dont teach anesthesia folks how to do EMGs?

seems fair that we should teach everyone everything, right? If EMGs are part of pain management (at least PMR and neurology folks will say they are) then shouldnt this be taught to those that didnt train primarily in these fields?

im mainly playing devils advocate here, as i could give a **** about EMGs as i believe they basically worthless and overutilized for "pain" issues. They are definitly helpful in some neurological issues, but when i hear of someone doing an EMG on a 30 year old with 3 weeks of pain in the low back and the posterior leg with a huge L5-S1 disc, it seems silly.

Thought I’d chime in here (I can’t resist an EMG thread :)). I certainly don’t consider myself a pain physician (not at your guys’ level anyway), but in the interest of disclosure I have anesthesia-based pain fellows who periodically rotate through my PM&R clinic as part of their training. So technically I am considered adjunct pain faculty.

According to the curriculum I’m supposed to be teaching the fellows electrodiagnosis in addition to neuromuscular/musculoskeletal exam knowledge/skills. So I do. And I do think it’s important, because at the fundamental level, non-PM&R or non-neuro pain docs should at least be able to understand the indications and limitations of EDX testing, and how to better interpret a study. I actually agree with you in that NCS/EMGs are not particularly useful with regards to pure pain management. And that’s coming from a primary EMGer. But is there some overlap between pain and neuromuscular disorders? Certainly.

I don’t teach the fellows the technical aspects of EDX testing since they are only with me 3-4 weeks at a time. If you use PM&R residency standards, you need to perform at least 200 EMGs during residency to be considered competent. You need an additional 200 post-residency to sit for the EMG boards (although not an ABMS recognized subspecialty board, it is well regarded in PM&R/neuro circles). There is no way any novice will get all of that in one month. That’s not the focus of pain fellowship training and, quite frankly, none of the fellows have ever expressed any interest in learning how to perform EMGs.

Are EMGs on the pain boards?
 
basic EMGs are on the pain boards but mostly testing to see if you can interpret the findings.

When I interviewed at Penn, they said they were going to teach anesthesia fellows to perform EMGs during the fellowship. Not sure if they actually accomplished that.

I agree - from a pure pain perspective - EMG/NCS is pretty useless. I treat a lot of subacute and acute pain - if there is weakness or numbness that is persistent after conservative measures and there is either no finding on MRI that correlate or more than one pathological levels that could correlate, I will do an EMG/NCS to help diagnose the cause of weakness/numbness and possibly decrease the amount of surgery needed. (one level microdiskectomy/foraminotomy vs multi level fusion)

No point in testing for just pain
 
When I took the pain boards, I remember one or two very complex EMG questions that I thought were waaay to complex for non PM&R fellows. But there were not many EMG questions at all.
 
If pain is the only symptom, EMG and NCV are usually normal and further frustrate the patient until they f/u with the ordering physician. They do serve as a shot-in-the-dark CYA.

I see no reason an anesthesiologist could not do a fellowship in EMG, if they so desired. They would start out the equivalent of a 2nd year PM&R or neuro resident, but should catch up quickly.

I'd be willing to bet, though, they'd see the same bias as a Neuro or PM&R applying for anesthesia fellowships.
 
I thought you could see positive sharps and fibs in the paraspinals near the epidural site. Am i remembering that wrong. I agree though, it certainly wouldn't effect any other aspect of the test


your probably thinking of medial br RF- affects multifidus
 
I thought you could see positive sharps and fibs in the paraspinals near the epidural site. Am i remembering that wrong. I agree though, it certainly wouldn't effect any other aspect of the test

yeah, i dont think an epidural would change an EMG at all. if you have the paper/reference id like to take a look, but i dont think it is so.
 
this is one of the problems with pain education....

did i learn good MSK, EMG, etc stuff during pain fellowship? not really... it was basic, nominal coverage.... did I learn how do do great discographies during fellowship? no, but enough to understand and get by...

what i have learned about our specialty is that as of right now these fellowships are really a platform from which we can dive into the real world, but we will be useless pain practitioners (nothing but stupid needle monkeys) if we don't spend time learning MSK, Neurodiagnostics, Imaging etc...

It is so important to constantly fine-tune these skills....

I am now 5 years out of fellowship and am still constantly learning and studying... I consider my MRI knowledge to be at the top of the game, my MSK is about 90% there - my understanding of various peripheral neuropathies is growing, have become a post-polio syndrome pseudo-expert.... but there are still gaps that i am constantly trying to plug...

so the argument that anesthesia fellows are dumb - is not an unfair argument but not entirely accurate... they are like all fellows: in need of learning...

why would an anesthesia resident/fellow be expected to understand the intricacies of a waldenstrom's macroglobulinemia?
why would a PMR resident/fellow be expected to understand the physiology behind a vagal episode?
why would a neurology resident/fellow be expected to understand how to do a good shoulder MSK exam?

so for all those guys/gals who posted about how much smarter they are than the folks they are supposed to be educating... your posts are inane because 1) you are supposed to be smarter than the folk you teach 2) you should take pride in taking an ignoramus and turn them into a smarty-pants and not deride them
 
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