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Is EMG test painful?
Can anyone help me interpret this: triceps has a mild increase in recruitment, amplitudes and 70% polyphagia. The only definition that I can find for "polyphagia" is food related eg. hungry. These segments are from my EMG. Thanks for any ideas or help.
I am scheduled for an EMG on Wednesday the 11th. They are looking at my neck. I was rear ended in an accident and this caused a disc to protrude and touch my spinal cord. I have been having trouble with weakness and numbing in my left arm. I'm a little nervous (also, I'm a wimp) and would like to know if it is painful. Thank you in advance. In conclusion, I wanted to know if the EMG was painful (not the neck injury).
Thank you for responding. I went through the test and it was quite tolerable. A couple of times I had pain, but mainly that was the needle. Thank you again.
Comment from another Patient
I am quite upset. I just had an EMG today performed by my doctor's associate....another doctor. He briefly explained the test. He did explain the first part about the electric current, etc., which was uncomfortable, tolerable. However, he then proceeded to unwrap a needle. I asked if it would hurt, he said "no...I'm just going to listen to changes in sound waves of the nerve." I must have asked him three times if he was going to keep sticking me with that needle and he said "no." But, as you know, he did stick me several times in my left and right arm...performed the test quickly, and I feel haphazardly. Two of the spots where he inserted the needle bled a lot and became swollen. (A hematoma, I think.) He wants me to go back for a test of my spine, which I don't want to do. I have 2 bruises and want to know how common this is with this test. I am duly upset because of his not being honest, him hurting me, and the bruises. Thanks for your feedback.
Comment from another Patient
I had an EMG and NCV about two weeks ago. The NCV was, to me, worse than the EMG, yet even the NCV itself wasn't that bad. I certainly do NOT dread my next EMG. There's just a minor pain at insertion, which I found less irritating than, for example, the needle prick associated w/ giving blood.
Thank you so much for responding. Yes, I do have to agree that it was the needle that caused the most pain, but I got through it just fine. Thank you again.
Leg is worse after EMG test done for hypokalemic periodic paralysis
My 14-year-old daughter was hospitalized a month ago after experiencing paralysis in her arms and legs. A pediatric neurologist determined that she suffered from a condition known as hypokalemic periodic paralysis. An EMG was performed the first night in the hospital, which confirmed the doctor's suspicions. An MRI, EEG, EKG and a pulmonary function test were also done to rule out anything else. Her arm function came back by the end of the first evening in the hospital. However, her legs came back a little slower. Her right leg came back suddenly three days later, however her left leg did not come back for another three days but the function came back floppy weak and painful to walk on. The neurologist scheduled another EMG five days later to again test her muscle function. Although the first test was three hours long and quite uncomfortable for my daughter, she was able to endure the pain. However, the second test was so agonizing with excruciating pain that my daughter was unable to complete the test. She only lasted about 30 minutes until it was so unbearable she could not breathe. After that second test, her left leg was worse with extreme pain. It has been almost a month now and it has not gotten any better and she is unable to bear her weight on it without pain. Could the doctor have damaged her sciatic nerve? The pain is from her hip all the way down her leg. She is on Diamox and Potassium to treat the hypokalemia. The other symptoms she had been having prior to being diagnosed with hypokalemia have disappeared (body pain and fatigue, insomnia, headaches and muscle and bladder spasms) except for this leg problem. She is receiving physical therapy twice a week and the therapist is as baffled as we are to why is not getting better. Please advise.
Nerve conduction studies and EMG are useful to diagnose hypokalemic periodic paralysis during the attack. This should reverse back to normal between the attacks. But, I am not aware of any case got sciatic nerve injury during such procedure. Please consult a neurologist to verify the problem.
Help w/ Interpretation of EMG Results please is it really poor
Can somebody help me interrupt the following EMG results? "Mild denervation potentials were identified in the left tibialis anterior alone. Changes of denervation with reinnervation were seen in the tibialis anterior and EDB." Also: MUAP L. TIB ANTERIOR Amplitude: Few+ L. EXT DIG BREVIS Amplitude: Few +, Polyphasia Few + RECRUITMENT L. EXT DIG BREVIS Pattern: - (minus sign)
EMG interpretation is best left to professionals who have performed the test and should give you an impression and interpretation of what they found. It is best to have your doctor explain it to you.
The sad part is this impression was likely written by his physician. Poor reporting.
That's possible in which case it is not an adequate report, and it is certainly incomplete.
Variation in normal EMG
My daughter age 19 had an EMG today due to a cervical spine injury 2 years ago. MRI shows minimal bulge at C4-5, 5-6, spur at C2 and an annular tear HIZ at c 5-6. She has complained of pain in her neck, shoulders, and right arm with numbness and tingling of her right 3rd, 4th, and 5th fingers. The EMG was read as normal but in looking at the numbers there was variation in the conduction velocity in her arms. Right Median 56.5 Left median 57.5 Right ulnar-elbow to wrist 64.4 Left ulnar-elbow to wrist 59.2 Right ulnar-across elbow 65.4 Left ulnar-across elbow 58.7 I understand these are normal ranges but should there be this much difference between right and left or could this be an indication of some early damage? She believes that the pain and sensory deficits are getting worse. On physical exam she has hyper-reflexia of her upper extremities and bilateral positive Hoffman's sign. The neurologist that did her EMG today said that she may have had some bruising of the cord resulting in these symptoms of cord compression. Thanks in advance for any information you can give me.
These values are still normal. The variation does not indicate damage in this case. You see, the difference has to reach certain value such as 15 m/s, to be significant or by itself reach lower certain values. However, the treating doctor always would take the findings within the clinical context.
Curious about EMG testing in CTS
My Doctor wants me to have an EMG test. I have carpal tunnel syndrome in both hands. I've heard it's very painful and many times not 100% accurate. Is the test very painful? and how accurate are they? Is there a surface test that can be done that's less painful and just as accurate? Please answer my questions as this test just around the corner for me, and I'm scared. Thank You
The study is divided into 2 parts; the nerve conduction studies, NCS, (surface test, no needle), where there is little electric shocks to study the nerves. The other part consists of inserting electrode (needle) in the muscle, little distance and it would induce little discomfort and pain. This pain is quite variable between individuals, but in vast majority both tests are tolerable and no squeal. It is important to do in patients with carpal tunnel syndrome (CTS). It is highly sensitive and accurate in CTS. I would, personally, say more than 90% (scientifically difficult to say 100%). Now, it is up to the examiner to perform both tests or would get away with the nerve conduction without the needle part. Actually, not every patient with CTS needs the needle part. It depends mainly on the patient's symptoms and signs, and obviously, on the obtained results of NCS, as well.
Please don't take Offense at this question! Can EMG be Rigged?
What about Valium / Xanax / or others before the test to calm the patient who has a driver???? I am rather needle phobic (though getting less each test) If a drug will help me feel better about the test and will not interfere with the test results than I would like some feedback. I am currently taking Vicadin and Oxyctin 10(at night time only). Anything with the word "NEEDLE" freaks me out. Sticking me multiple times, and leaving it in seems worse. Though many have told me that the EMG is not pleasant but bearable I still would like to know about possible med's for scary cats like me.
First of all; I do accept your question, no offense, it is nice interesting question. Now, back to question, EMG and nerve conduction studies are done under strict internationally controlled criteria, similar to operating computer or driving a car. You must follow rules. In our field, therefore, EMG and nerve conduction studies follow 2 lines: one is technical which cannot be rigged; we go by numbers and parameters. Having said that, we should always know that these studies have limitations and can be normal even if the patient has symptoms. This brings me to the second line, the interpretation part. Here the doctor explains the findings and then would attempt put data or findings together for certain disorder and to correlate the findings with the patient symptoms. Here, comes the experience of the examiner and "tailoring or rigging", but do not get me wrong, even here we follow rules of medicine in interpretation but of course depends on experience and knowledge of examiner in putting the data together and considering some findings as significant or not. That is why, in our reports we always have the technical data are written down for the referring doctor to see, followed by examiner report and interpretation, this may vary but usually well agreed upon. You see we do, with God help, our best for the patient care. Regarding your other point, EMG can be normal if you have tingling in both little fingers. EMG is useful to diagnose a lesion of the nerve itself or radicular lesion. But, if due to central lesion (spinal cord or brain), then EMG does not help, other radiological evaluation is needed, but it is up to treating doctor.
Hello. Could you provide reference to the criteria which you refer to - i.e. what is the governing organization or standard? And is there a web site? Also, is there a type of EMG which does not have any numbers of a graph associated with it- and if so when would this be the case. Thanks
The website of American Association of Electrodiagnostic Medicine is useful: www.aaem.net, especially go to practice parameters (http://www.aaem.net/practice_parameters.htm) or (http://www.aaem.net/publications/ practiceaids.html#Guidelines%20in%20Electrodiagnostic%20Medicine). Regarding your last point, I am not aware of EMG without numbers or graph.
I am thinking those machines are messed up also cause I have severe pain and numbness in my right leg and foot and they said that everything showed normal but I told them that something isnt normal.
In need to understand some terms in NCV report for CTS
I have had a nerve conduction study of the upper extremities: revealed prolonged terminal latencies of the Rt. median motor, sensory, midpalmer bilaterally; left mid sensory mildly prolonged as well. Abnormal nerve conduction exam of both upper extremities are suggestive of focal median nerve entrapment neuropathy across the wrist (CTS) bilaterally, Rt. > left. I have yet to actually see the neurologist, appt set up; however in the mean time, what's the translation of terminal latencies prolonged, abnormal exam. What is a large fiber diffuse peripheral neuropathy, (states no evidence of). The only repetitive motion I have in my life is 6-8 hours (intermittently) on my job, I case and deliver mail. I have filed wc/occupational illness. I had the NCS done before filing so to have proof of condition. Talk to me someone! I am in braces 24/7 weight limit 15lbs lifting until owcp gives an answer. I'm concerned...surely my job duties has caused this, right? Intimidation is not a pleasant experience.
To be precise and go to the first point, "the terminal latency prolonged" means that, there is pressure or entrapment of the median nerve causing slow of conduction or response on electrical stimulation of the nerve. The second point, "large fiber diffuses peripheral neuropathy"; there are 2 kinds of nerve fibers; small and large nerve fibers. The usual nerve conduction studies deal only with large nerve fibers. Therefore, when those nerve conductions are abnormal, then we refer to large fiber affection. Now, the last point. The CTS is very common condition all over the world. It is related to repetitive actions. Thus, it can be an occupational illness.
Thank you so very much for the response. This is about all the response I can muster right now.
EMG Technique (description)
I am scheduled for an EMG Test after some concerns were noted in my nerve conduction test in the upper extremities. Could someone explain his experiences with the test? Painful? How long does it take? In general, what can I expect? Thanks.
The needle EMG part of the test consists of inserting needle probes in the muscles, usually, 4-5 such insertions per extremity. No electrical currents are delivered by the needle, no blood is drawn and nothing injected; just a sampling of the muscle to see if it is normal or not. Though the sticks are less painful than injections, they are nevertheless uncomfortable. One extremity needle testing takes about 10-15 minutes and usually reveals very useful information about the nerves and muscles.
EMG Technique (use in determination of injury duration)
Can an EMG and nerve conduction test tell if nerve damage is from an old injury or a new injury?
Yes, the needle part of the test can usually tell whether an abnormality is from an old injury or a recent one (under 6 months old)
Heat role in EMG results
I was given an EMG test, the doctor did not like the results of the test. So he placed heating pads on both of my hands/wrists/arms for about 10 minutes & re-took the test, right side first. I passed on the right side but again failed on the left. So he heated me left side up again & I passed. Is this a normal procedure to heat up the arms & etc. I was not cold nor cold to the touch? What is the reasoning behind the heating procedure if it is normal?
The change in temperature can affect the nerve conduction studies to great deal even in normal persons; the cold (even if you do not feel it) can cause slowing in nerve conduction. Therefore, it is important to check the temperature (skin temperature) before, during the test or at least in case of slow nerve conduction.
Practical use of EMG in trauma
Can an EMG and NCS differentiate when an injury actually occurred? I would like to email someone to discuss this more
Yes, EMG and NCS studies are helpful in nerve injuries, for instance after trauma
Nerve injury due to bulged disc; is it reversible?
If a disc has caused nerve damage in an arm, will it be permanent or can it be fixed?
Nerve damage is reversible when the nerve is still connected (in continuity) and the cause of the damage has been removed. Disc bulges usually leave the nerve connected, so when the cause is eliminated (or gets better on its own) the nerve regenerates. Nerve Growth is slow though, about 1 mm/day.
Mixed median nerve neuropathy with demyelinating features
I was tested two years ago and just advised today that I have the above diagnosis. I would like more information as I was told there is nothing to do since the damage has been done, except pain control and seeing a neurologist. Where do I find out more about this?
That does not sound like a very good EMG diagnosis because it doesn't tell you much. Usually demyelinating lesions of the peripheral nerves heal very quickly, unlike axonal lesions, where the nerve fiber is cut, which take longer to heal. I would have that report looked at by a qualified EMGer, neurologist or physiatrist
Increased insertional activity
How does increased insertional activity sounds like? (The one, which is seen early in the course of denervation)? Does it sound different than cramps - poorly relaxed muscle?
That's a tough one to describe in words, but basically what I call increased insertional activity is when I begin to see insertional potentials (and I am away from an end-plate zone) which look like fibs and positive waves but which never become spontaneous and persist after I stop the insertion. The sound is a bit similar to a brief end-plate zone noise, which does not persist. It is a much "quieter" sound than that of a cramp or a poorly relaxed muscle.
Hi! Thank you for your elaborated answer. I know that a cramp (or poorly relaxed muscle) sounds like a high frequency, repetitive bursts very very very fast (like a machine gun fire)-does increased insertional activity SOUNDS also like that?
No, nothing like a cramp, much quieter.
Normal EMG in a complaining patient
Well I had my EMG done and it wasn't too painful but they didn't find anything in it so they really don't know what's wrong with me. My orthopedic now suggests physical therapy. This is driving me crazy I've had this injury since November. I just want to know what's wrong with me.
An EMG can still be negative and you may still have a pinched nerve. But in situation like yours the pain may also be musculo-skeletal in nature, that means from muscle spasm, local joint inflammation or a sprain. If Physical Therapy doesn't help, an MRI of the spine would be useful to make sure there is no pinched nerve.