Join this vibrant community of professionals eager to exchange ideas, share resources, and engage in meaningful discussions. Use this platform as a sounding board to seek advice for navigating challenging cases or career decisions, and receive expert guidance from generous peers who want to help you succeed.
In order to comment on posts and view posts in their entirety, please login with your AANEM member account information.
I was wondering how many of our members have been monitoring or requiring their staff members to receive COVID-19 vaccination.With regard to patients, we have been administering antigen rapid testing in the office to all the unvaccinated . While this is not as accurate as laboratory PCR testing, at least it gives us some information. Regardless of the patient's vaccination status, we still require masking of all staff members and patients.
59 yo female with numbness on the the thenar eminence following a repeat CTS release in 01/2021 (first release surgery was in 2005). Both open release. The numbness pre-op was on the median fingers. NCS (median SNAP with mid palm stim, median CMAP, median-radial thumb comparison) and EMG (including APB, OPPONENS) are normal. Suspecting damage to the palmar cutaneous branch of the median nerve. I do not know how to assess this branch. Help me please.
I was hoping to get some input on this interesting EMG case that I saw the other day. The patient is 65 year old female who was referred for an electrodiagnostic study to evaluate the bilateral lower extremities. Patient presented to the hospital on 4/19/21 s/p being down for 2 days secondary to shock requiring intubation and pressor support. She had a complicated hospital course and ultimately was suspected to have an acute spinal cord process causing paraplegia, however, MRI C/T/L-spine was unrevealing (MRI limited by motion artifact, body habitus, and body wall edema). There were no sensory or motor impairments in the bilateral upper extremities. She was referred for EMG of the bilateral lower extremities due to concern for critical illness neuropathy vs. spinal cord infarct.
EMG of the bilateral lower extremities was performed on 8/16/21.
Physical exam: 0/5 strength in the bilateral lower extremities (hip flexors, hip adductors, hip abductors, knee flexors, knee extensors, ankle dorsiflexors, ankle plantar flexors), absent sensation to light touch distal to the groin bilaterally, and absent patellar and achilles reflexes bilaterally. There was significant pitting edema in the bilateral lower extremities to the knee bilaterally.
NCS: Sural and superficial sensory responses were unobtainable bilaterally. Fibular and tibial motor responses were unobtainable bilaterally. Right median sensory, ulnar sensory, and superficial radial sensory responses were normal. Right ulnar motor and median motor responses were normal. Right ulnar F wave was slightly prolonged at 33.2ms.
Needle EMG: There was active denervation in proximal (TFL) and distal lower extremity muscles (vastus lateralis, tibialis anterior, fibularis longus, medial gastrocnemius, and short head of biceps femoris) bilaterally with no evidence of axonal continuity in any sampled muscles of the bilateral lower extremities. There was active denervation in the right middle/lower lumbar paraspinal muscles. The left middle/lower lumbar paraspinal muscles were normal. The right first dorsal interosseous and right deltoid muscle were normal.
Conclusion:
Abnormal study. Technically challenging study due to significant bilateral lower extremity edema and limited mobility due to bilateral paraplegia.
Bilateral lower extremity sural sensory, superficial fibular sensory, fibular motor, and tibial motor nerve conduction studies showed no response. Needle EMG examination of the bilateral lower extremities showed diffuse active denervation in proximal and distal muscles with no evidence of axonal continuity in any sampled muscles. Taken together, these findings localize the pathologic process distal to the level of the dorsal root ganglion, and could be explained by severe bilateral lumbosacral plexopathies vs. a severe axonal, sensorimotor peripheral polyneuropathy.
There is a possible superimposed right lumbosacral radiculopathy that is non-localizable.
There is no electrodiagnostic evidence of a superimposed left lumbosacral radiculopathy.
There is no definitive electrodiagnostic evidence of median neuropathy, ulnar neuropathy, or myopathy in the right upper extremity.
My practice is devoted exclusively to EMG/NCS testing. I do not provide ongoing care for any patients and all my testing is non-urgent. During this time of the delta variant surge, and in the interest of the safety of my vaccinated patients and staff, I am considering limiting my practice to vaccinated patients.
What are the thoughts in the AANEM community regarding this? Has anyone limited their practice in this way?
Do we have a consensus for the standard of practice for IVIg treatment small fiber neuropathy?
Some insurers will cover, others not. I understand the literature, such as it is, does not clearly support IVIg one way or the other.
I would like to open a discussion about the p-value fallacy.
As a preface – The p-value fallacy has been known and discussed for many years. Yet, little to no change seems to be happening in the medical sciences with regards to how we use and interrupt p-values (though alternate solutions have been proposed). I have only recently read into this topic and feel the implications for medical research are large and unpromising (hence my desire to hear the community’s opinion on the matter).
My understanding is such:
The common way (in medical sciences) p-value is taught/understood is categorically wrong. P-value was developed as part of significance testing. However, it has been erroneously applied to represent a type I error rate (or alpha level) in hypothesis testing. In hypothesis testing - null and alternative hypothesis are developed. Then an alpha level is set (usually and arbitrarily set at .05 or 5%) and an experiment is done. If the observed difference between the null and alternative hypothesis meets or exceeds a p-value of 5%, we reject the null hypothesis in favor of the alternative hypothesis (with the understanding that there is a 5% chance that the observation we made was by chance alone).
The problem is that assumptions made in significance testing (p-value) cannot be seamlessly transitioned to hypothesis testing (type I errors). Yet, this is exactly how it is taught and what is routinely done in medical sciences. Specifically, the null hypothesis in significance testing is assumed to be true. Therefore, it is categorically incorrect to apply it to hypothesis testing where the null hypothesis can be rejected. To bridge the p-value of significance testing with the type I error rate of hypothesis testing, and to mathematically quantify the p-value fallacy, researchers have used a Bayesian framework. Conclusions resulting from Bayesian analysis are multifold with two notable issues, 1) p-values routinely (and at times wildly) underestimate the false positive rate, and by extension, 2) p-values cannot give a specific percentage to uncertainty without considering priors (i.e., if we reject the null hypothesis, we cannot say there is a 5% probability what we are seeing is from chance alone without considering the prior probability the hypothesis was true pre-experiment).
Taken together this would argue the p-value is widely misunderstood and misused with one corollary being we are routinely reporting “statistically significant” findings when none exist. This problem is superimposed on a myriad of other potential problems in medical research – some related to p-values (the reproducibility, or lack thereof, of p-values under theoretically identical experimental conditions) and some not (wide-spread bias, confounding, small sample sizes, lack of reproducibility of new research findings, conflicts of interest, etc).
Below are some resources that have shaped my view. I am very interested to hear the community’s thoughts and the possible implications for medical research.
Colquhoun, D. (2017). The reproducibility of research and the misinterpretation of p-values. Royal society open science, 4(12), 171085.
Gao, J. (2020). P-values–a chronic conundrum. BMC medical research methodology, 20(1), 1-8.
Wasserstein, R. L., & Lazar, N. A. (2016). The ASA statement on p-values: context, process, and purpose.
Goodman, S. (2008, July). A dirty dozen: twelve p-value misconceptions. In Seminars in hematology (Vol. 45, No. 3, pp. 135-140). WB Saunders.
Hey all, I'm in the process of starting up a PM&R EDX Lab in the context of an existing academic EDX lab and I would like to set things up so that patients can electronically enter their history information prior to the visit to help with clinic flow. Does anyone have a patient intake form that they really like that we can use as a template that they would be willing to share? We are also giving a talk on Building a Successful Neuromucular practice at the fall meeting and would love to share it there as well or share a composite of the ones that we find. Thanks everyone and happy Friday! JWN
Hi all,
I wanted to ask for community/expert input on how you approach interpretation of distal latency with regards to demyelination, in the setting of severe axonal loss and muscle atrophy?
I believe it’s generally accepted that distal latency can be prolonged up to about ~130% of the upper limit of normal in the setting of axonal loss (without implying superimposed demyelination)-- largely due to loss of the fastest fibers. For more proximal conduction velocities, ~75% of the lower limit of normal is used, which seems roughly commensurate.
However, when amplitudes are extremely low (e.g., 0.1 mV for a motor NCS), it seems plausible that other factors (beyond loss of fastest fibers) could cause further latency prolongation (without implying demyelination). Some of these include:
(a) distal collateral sprouting: increased NMJ transmission time
(b) distal collateral sprouting: more slowly conducting immature myelin (and decreased spacing of nodes of Ranvier)
(c) increased electrical transmission time through muscle due to atrophy
(d) inability to accurately measure motor onset latency (only seeing "tip of the iceberg" of the motor response
Importantly, it seems to me that all of these factors would affect the terminal portion of the study (distal latency) disproportionately (relative to the more proximal conduction velocity measurements)-- without implying demyelination-- and that these mechanisms bring us beyond what's expected for loss of the fastest fibers. In this context, 130% of the upper-limit-of-normal as a threshold seems too low/lax (might overcall demyelinating disease in the setting of end-stage axonal loss?). I don't know if this has systematically been explored: the range of latency prolongations expected in extreme axonal loss.
In this context, do you have a threshold for assessing distal latencies potentially concerning for focal demyelination in the setting of extreme axonal loss? (A relevant clinical application would be looking for evidence of superimposed ulnar neuropathy at the wrist in a patient with established ulnar neuropathy at the elbow with severe and chronic end-stage axonal loss).
Sandra
I am curious if anyone in the audience is a Medical Director of all Electrodiagnostic Services at a large hospial system (preferably academic medical center), particulary where neurology and PM&R labs are combined under this Medical Director? What are the job responsibilities of the Medical Director in this situation, who do they report to in the hospital? Do they receive any compensation for their time? What has been some of the pros/cons of this arrangement? Thanks for your help!
Hi my name is David Phrathep and I'm a second year medical student that just recently became a member of the AANEM. I'm currently looking for research opportunities involving neuromuscular medicine and PM&R. I'd be appreciative of any opportunity and I'm eager to learn. I'm able to start assisting immediately and I'm enthusiastic about the field. Thank you.
A young male (well...my age of 46) body model and actor came to me for electrodiagnostic testing that revealed a fairly textbook left sided C8 radiculopathy. Imaging revealed single level severe neuroforaminal combined spondylotic and discogenic stenosis. cervical injection improved pain but he was not recovering sufficiently and opted to single level neuroforamenotomy.
All of his symptoms resolved and his strength has improved to a self-reported 80%.He is still fasciculating in those C8 muscle groups.
Prior history of healed triceps rupture but with residual loss of muscle bulk many years ago. This has compromised his ability to sculpt his left pectoral muscles to the same degree as the right.
He is looking to get as close to 100%. I already explained to him that collateral sprouting has a timeline and that he should keep working out (without overdoing it) to optimize recovery.
Is there anything else you would recommend? I was considering functional neuromuscular electrical stimulation but i'm not optimistic that it will help.
A patient recently reported that immediately following NCS performed for neuropathy that he suffered severe constipation and then an inability to distinguish between the need to defecate and urinate. He attributed this to the "amperage" used during the study and that these symptoms continue (two months). I indicated I had not heard of such a thing but would inquire of my colleagues.
How do paralytic meds (in the ICU for example) stay in the body and what is the effect on the EMG and NCS? And how soon can you do a SFEMG or rep stim after the patient is given a paralytic?
I came across the above normative values (see hyperlink above) and appreciate the new acceptable CV drop for the Ulnar nerve across the elbow as at least 15m/s or 23% drop in CV. This was introduced in the Spring meeting.
However,
Is the absolute value of less than 43m/s across the elbow significant as quoted in the normative value chart ? Even if there is no significant drop in CV in comparision to below / above the elbow (i.e. a drop of less that 15m/s) ?
I have seen three people in the past couple weeks who believe their acute neurological symptoms in the upper limbs were related to the vaccines with onset within a few days. One had profound denervation consistent with a plexopathy, but he also had significant cervical spondylosis.
I just had 28 year old man referred for an EMG. Symptoms started about 6 months ago. Numbness in arms and legs . All the same. He was much worse at the beginning and was unable to walk. He uses a cane currently. Poor historian. 2+ upper and absent lower. Full strength.
All thought to be alcoholic. He was a heavy drinker for few months per his report???
could not get any sensory in 4 rextremities. LE motor, very low amplitude or absent. Upper motor is normal. No delayed latency or slow conduction velocity.
No pain at the onset.
EMG is the confusing part. Quads with 3+ fibs. Legs with no fibs but slightly large and polyphasic units. Upper is ok. Lumber paraspinal with no fibs.
I was thinking sensory neuronopathy until I stuck the needle in the quads.
My emg machine finally died, so I borrowed my friend's Cadwell Sierra Ascent. Works great besides for a phantom waveofrm with sensory studies. It always occurs around 1.2 ms at 8 cm or 1.5 ms at 10 cm. I think it's shock artifact but I'm not sure. I have the notch filter on, exam table unplugged, use a shielded shuttle cable, keep the electrode and stimulus cables away from each other, tried using the machine in different rooms, etc.
I attached the waveforms below (or at least I hope I did).
Does anyone know what this wavefore is and how I might get rid of it?
Hi there. I run a quite busy EMG lab that is accredited and I am employed under a huge medical system. I am wondering about venturing to establish my own independent EMG lab. Are there any guidance or resources out there that can help me? Thank you in advance.
Does anyone have any experience with ultrasound billing? Is anyone doing it as an extension to the NCS/EMG?
Can you still do Ultrasound when a primary asks for NCS/EMG only?
How should increased ulnar distal sensory latency, with normal sensory nerve action potential and normal ulnar motor NCS, and otherwise normal NCS of the median and radial nerves, be interpreted?
There have been references to "muscle pairs" for example in the Peripheral Nerve questions (question 3 on my set), it said that fibularis brevis and fibularis longus (peroneus brevis and peroneus longus) are a muscle pair.
There was another question suggesting that coracobrachialis and pectoralis are another muscle pair. Also, extensor pollicis longus and latissimus dorsi as another pair.
Please can anyone explain the defintion of a muscle pair.
I enjoy participating in the AANEM Connect Forum for a number of reasons. There are very fundamental questions posed on a frequent basis that cause me to pause and ask myself, ‘Why didn’t I think of that?’ Also, I continue to learn
new things when others contribute their thoughts and experiences. Connect is an excellent opportunity for members to interact and to address any topic, including those that may not be discussed
at an annual meeting or journal article.
