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  EMG/NCS & MRI positive for cervical radiculopathy but normal myelogram  
  I had EMG and NCS done in november99 positive for c6-7 radiculopathy also an MRI showing c 6-7 bulging disc. Just had a myelogram recently and the doc said it looked "real good", and I don't have a disc or nerve problem. Now I'm confused
  Answer Diagnosis of radiculopathy or disc herniation (root lesion) depends on clinical examination, EMG and radiology including MRI and Myelogram. The myelogram is most accurate way to detect disc herniation. Now an abnormal EMG can result from herniated disc in your case but the herniated disc may be too small to be significantly "appreciated" by myelogram, so considered insignificant by myelogram, although it is causing nerve root pressure symptoms and abnormal EMG. Furthermore, an abnormal EMG can be explained by other causes distal to roots, which could give similar EMG findings such as Brachial plexus or peripheral nerve lesions.
  Needle EMG and Radiculopathy and who is authorized to perform EMG?  
  Is a needle EMG always required to suspect that a patient has radiculopathy or can a Dermatomal Evoked Potential Test and/or a Somatosensory Evoked Potential test raise suspicion that a patient has radiculopathy? Can a chiropractor or a podiatrist perform a needle EMG?  
  Answer 1 Evoked potentials test the sensory roots (they go from the periphery to the spinal cord) but don't test the motor roots, those which, through the muscle, control movement. Therefore Evoked potentials can only tell you if you have a sensory radiculopathy. Only Needle muscle examination can tell you if the motor root is involved. You should also know that some studies indicate that EMGs may be (falsely) negative in up to 30% or 40% of root lesions.
  30-40% false negative in detecting root lesion  
  In your answer to a previous post you stated that some studies have indicated that needle EMG can give false negatives 30-40% of the time in detecting a root lesion. Why is this? Also does this apply strictly to testing for radiculopathies or other disease processes as well?  
  Answer 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
  Posterior Interosseous Nerve Syndrome (PIN)  
  I just had an EMG a few weeks after a nerve conduction test revealed concerns in my elbow to wrist area. The EMG Doctor diagnosed me with PIN Syndrome on the spot. I have not heard from my primary care physician yet with the complete analysis; however, I don't know what caused this or what to expect from here. Up till now there has been muscle loss around the wrist area and slight weakness in the hands. Is there a means to predict what I can expect in the future or what possibly causes PIN? Thanks.  
  Answer Yes, thanks for the clarification; the 30-40% false negatives in the studies I quoted applies only to radiculopathies.

This is due to many factors, including the fact that while radiculopathies may be painful, they may actually not cause any nerve damage (which is what is picked up by the needle exam of the muscle), sampling or interpretation errors, detection error due to poor relaxation, timing of the exam etc..

  Comment Thanks for the clarification. Are there any general statistics in regard to false negatives or diagnostic accuracy in general for EMG? Or are there statistics for individual disease processes such as neuropathies, myopathies etc?  
  Answer 1 Well, generally speaking, in compression or entrapment neuropathies (such as Carpal Tunnel, Ulnar, Radial or Peroneal Neuropathies, or Bell's Palsy), the yield is pretty high (I do not have numbers) even though there are still false negatives. In root lesions, as I mentioned before, the yield drops, as it does in neuropathies and myopathies, probably again in the 30-40% area. EMG is considered to have the highest yield in entrapment/compression neuropathies.  
  Answer 2 I would like to tackle this point by talking about how the electrodiagnosis contribute to diagnosis of myopathies in form of false positive or false negative. First of all, it is important to keep in mind, unfortunately, that none of the abnormalities in EMG is pathognomonic or specific for any single myopathic disease. Second, EMG is important but general guide to diagnosis, but we should keep in mind again that exceptions do occur. Now, the question, could EMG be false positive in myopathies? The answer is yes, due to technical reasons (MUP measurement, over-reading), also it can be false negative, due to again technical reasons (MUP measurement, simply missing mild changes) or mistaken the changes to be due other cause. Regarding neuropathy, again, false positive can occur due to technical reasons, temperature and age. While the false negative can also be due to some technical reasons in the recording.  
  Cold blue hands with severe pain  
  I am a 31-year-old female and have been diagnosed by 4 different doctors with abnormal nerve conduction. They are now checking chromosome 17 and a couple of them say my arms will only get worse. I am in extreme pain most of the time, I have muscle spasms in both my forearms, At times I cannot move my hands at all and the veins or nerves get so swollen they look like they are going to come out of my skin. My hands are constantly cold and my fingernails turn blue to the point where people have thought I was wearing nail polish. It pains me just to type this. The pain goes no higher than the elbow. Are there any answers you can give to me? Thank you for your time.  
  Answer I am not quite sure what the abnormality is on your nerve conductions but symptoms you describe involve more than just your nerves and at least involve collagen tissue and your blood vessels (the coldness you describe and the change of color sounds like Raynaud's phenomenon). Usually Rheumatologists are specialists in this area. Any nerve or nerve conduction abnormality is a secondary phenomenon and can be diagnosed/treated by a Neurologist.
from another
A friend’s daughter has those symptoms and she was diagnosed with Raynaud’s. Have you been checked for that? Good luck  
  MRI & EMG positive while myelography negative in cervical radiculopathy  
  I had EMG and NCS done in november99 positive for c6-7 radiculopathy also an MRI showing c 6-7 bulging disc. Just had a myelogram recently and the doc said it looked "real good", and I don't have a disc or nerve problem. Now I'm confused  
  Answer Diagnosis of radiculopathy or disc herniation (root lesion) depends on clinical examination, EMG and radiology including MRI and Myelogram. The myelogram is most accurate way to detect disc herniation. Now an abnormal EMG can result from herniated disc in your case but the herniated disc may be too small to be significantly "appreciated" by myelogram, so considered insignificant by myelogram, although it is causing nerve root pressure symptoms and abnormal EMG. Furthermore, an abnormal EMG can be explained by other causes distal to roots, which could give similar EMG findings such as Brachial plexus or peripheral nerve lesions.
  Conservative Vs. surgical management for c. radiculopathy & myelopathy  
  I had an MRI with the following impression: Narrowed right C5-6 neural foramina from osteophytes. Slight flattening of the central and left Paracentral thecal sac at C5-6 from disc bulge. I saw a neurosurgeon who recommended surgery after evaluating the history since onset (3 months ago) of arm numbness/tingling stabbing spasms, reflexes and MRI. Neck pain in almost not present now. Arm numbness/tingling pain spasms continue but are less frequent and intense. Do you think I am a candidate for surgery?  
  Answer Tough call. Generally speaking, neurosurgeons recommend surgery when they think surgery will help. They do not like bad outcomes. One thing for sure, if you start developing arm weakness/wasting, it is a sign that you're developing nerve damage and surgery becomes more of an indication. If your symptoms are improving however, waiting it out (if no weakness or wasting develops) may give you an idea if it is going to heal by itself or not. Nothing can replace a good exam however and if you are unsure of what to do, seek a second opinion.
  Comment I forgot to add that the end of my thumb, the last knuckle, is "always" "constantly" a little numb now, since mid June. Which the neurosurgeon said I would never get back because the nerve root was damaged not just irritated & inflamed. Sometimes I feel as if it's creeping up my arm and my wrist is ever so "a tiny bit" numb all the time now too (as it feels just a little off). Would this information increase your opinion that surgery would be helpful to prevent and improve my situation? Thank you by the way for your thoughts on the subject.  
  Answer Nerve damage, with no prospects of it getting better on its own, is usually an indication for surgery. Again, if you are at all unsure, it is best to seek a second opinion. It would be useful to get an EMG before the surgery however to determine the amount and location of nerve damage. Best of luck.  
  Comment Thank you again for your advice. I saw an orthopedic spine surgeon and he prescribed VIOXX and 3X's a week (for six weeks) of PT (physical therapy); heat, massage, traction and so on before re-evaluating surgery need in six weeks. My right arm reflexes are still there--- but way off, the numb/tingling stabbing pains are less intense and they now only come with certain head/neck/arm positions. I'm hopeful the PT will do the trick. Thanks again!

I have another question. What is the significance of a diagnosis of cervical spondylosis with myelopathy? What is Myelopathy and how does a neurosurgeon diagnose it. Another words what are the symptoms of cervical myelopathy (at the C5-6 level for example)?

  Answer Cervical Spondylosis with myelopathy means that you have a tight spinal canal in the neck area. The spinal cord is inside that canal of course and it comes under pressure because of the lack of space. This is what is referred to as a myelopathy (myelo refers to the spinal cord and pathy is used to indicate disease). The diagnosis is made by CT or MRI and or myelogram. The symptoms may involve root symptoms (the ones you described above) and also some weakness and increased reflexes in the legs if the canal is too tight.  
  Comment Thanks for all your input. Seeing another doctor helped. After 6wks of PT I saw the Orthopedic doctor yesterday again, for re-eval after PT. He said I have beaten the odds.. Considering how large my disc bulge was, the swelling has gone done enough so that I no longer have myelopathy nor is there permanent damage. He did say that I had about a 30% change of needing the surgery sometime in the future, due to the nature of cervical spondylosis.

In your experience would you agree or disagree with the likelihood of future surgery need in such cases?

And what would be the best course of action to optimize my continued recovery, non-recurrence (including myelopathy) and therefore the need of surgery (ACDF)? Thank you!

  Answer I cannot say what the chances exactly are but I think 30% is about right. I also understand your concern about doing the right thing to avoid recurrence. In such cases however it is difficult to predict what may cause such recurrence. Needless to say staying fit and getting right away in treatment (PT, anti-inflammatory etc.) when symptoms develop would help. Other than that, in all practicality, there is little you can do to prevent events outside of your control.
  Comment Thanks again; gee I've said that a lot. My doctor advised me also about staying fit. I am slowing entering back to my workout routines. He also gave me an "ER" prescription (fill only if symptoms come back) for anti-inflammatory and advised me to 'save up' PT visits encase of reoccurrence; as insurance cuts one off after X amount of visits per contract year. Should symptoms reoccur would you advise getting a myelography before surgery this time? And why?  
  Answer If you mean a myelogram, that's a purely surgical decision, in most instances an MRI will suffice to see if there are any significant changes since your last visit.  
  Husband EMG who has shoulder neck and elbow pain with negative MRI  
  I'm concerned over my husband. He had a negative MRI and had following EMG findings. He has gone through Facet block with no relief and has bad L Shoulder, neck, and L elbow pain going down two small fingers with positive Tinel sign. Other options we could look for it has been a year now. Test was 4 month after accident. Muscle Ins Act Fibs PSW FASC CRD AMPL Duration Poly REC The reading for his lumbar area was L Tib anterio I 0 0 0 0 n n I rr R " " I 0 0 0 n n I rr L Medial Gas I 0 0 0 n n n rr R " " I 0 0 0 n n n rr L Vastus Med n 0 0 0 0 n n n rr L Bicep Fem I 0 0 0 0 n n n rr L Paraspinal I 0 0 0 0 R " " I 0 0 0 The upper area showed L deltoid I for insertion and rr for recruitment, rest normal L Infraspinatus all normal L tricep I for insertion and rr for recruitment, rest normal L flexor carpi ulnaris I for insertion, PSW, RR recruitment, rest normal R flexor carpi ulnaris I for insertion, rr for recruitment L & R first dorsal interosseous I for insertion, PSW, rr for recruitment, rest normal L & R extensor digitorum communis I for insertion, rr recruitment, rest normal L paraspinals I for insertion, rr recruitment, rest normal. My husband had no readings for any fibs or fasc just 0. Any help appreciated thank you  
  Answer It is very difficult to interpret an EMG study over the web. Naturally the EMGer who performed the test is best qualified to give you the definitive answer.

From the limited information I have, these findings (PSW, polyphasic units.) can be seen when there are pinched nerves in the back and the neck. In the example you give me, the muscles involved point to the L5-S1 nerve roots in the low back and to the C8-T1 nerve roots in the neck.

  Radiculopathy with negative EMG for nerve damage  
  I have constant numbness/tingling in my R LE (bi lateral at times), increased with activity. Can you explain how I can have the diagnosis of radiculopathy with a negative EMG? What exactly does it mean, and will epidural steroid injections help? Does it mean it's permanent? Also, how could a sensory root lesion be detected, by NCS?  
  Answer To explain further why the EMG is negative in some cases with radiculopathy. The medical reasons were pointed out in previous posting. But I would like to say, if you have a car with maximum speed limit of, say 120, then it cannot go faster than that. Similarly, in EMG it has its own limitations we cannot exceed. We cannot do more than what it could give; otherwise, we do not need any other tests. The EMG is complementary or extension to medical examination and it does not replace or substitute a good medical examination by all standards. To go back to your question of epidural steroid injection, it may help, and it is up to your treating doctor to decide. A negative EMG in your case does not mean that your symptoms are permanent. On the contrary, a negative EMG can be reassuring. Finally, I am sorry, I do not know how to help you with the last point.
  Puncture to nerve in inner elbow area  
  I was in for a routine physical on March 29th. And upon a blood draw I experienced intense pain shooting to my left hand. I thought right away it was my nerve. The lady that took the blood said she had never experienced that either. I have been seeing an intern and he had his dad who semi-retired and is a neurologist do a nerve conduction test last Wednesday. The test came out negative. I have numbness in my hand and fingers I have had what my therapist call a lot of trigger points in all areas of my lower and upper arm all the way to my underarm. I have been going to therapy for three weeks being treated with heat and electro therapy. Should I be as concerned as I'm on Vioxx for the inflammation if I don't take it by the end of the day my arm is clinched so close to my side because my whole arm hurts. Is there another test I should have done? Should I continue the therapy and give it time? Would an MRI tell me what is going on in there, could she have got a tendon also? I thought I should give you all of my symptoms. It started with tingling in my hand and fingers shortly after it happened. The tingling started spreading up my arm and I started getting increased discomfort in my elbow area. Within 5 day's the muscles in my arm started hurting. Today my fingers are numb and are very sore and stiff. My muscles in my underarm hurt a great deal as well as my forearm and bicep. The discomfort in my arm changes spots. The pain in my fingers is consistent I'm sorry to post twice before a response but I just found this forum and I have been searching for answers to insure I am getting the right treatment. I have never had something like this. It's been a month. I have been told it takes a long time for nerves to heal. I guess I just want to know how long, and is it my nerve. Will an MRI show what it is or would you recommend an EMG? Thanks so much, I'm scared! Thank you for any advises you can give me.  
  Answer According to your symptoms, it seems like a nerve lesion by injury or pressure, probably the median nerve was injured during needle puncture. I wonder did you have an EMG needle examination of the muscles or just nerve conduction studies. If it is so, then I think you need to see your neurologist again to do (or repeat) EMG needle examination of the muscles, which should be helpful to exclude nerve lesion and its degree. I think the EMG is more helpful in your case than MRI.
  Comment I went to a Neurologist yesterday and was diagnosed with a median nerve lesion. I have been treated for 6 weeks for ulnar neuropathy. Lots of therapy and taking Vioxx but I still had a lot of pain. You suggested I see a neurologist and get an EMG. I found a sharp Dr. and the Dr. agreed he will be doing the test on the 22 of May.
My question is He gave me a prescription for Neurontin, I was wondering if it will interfere with the test in any way.
I am very thankful for this forum and for all your help. I will keep you posted. I still have a great deal of pain in my whole arm and I hope the Neurontin will help.
  Answer I hope all the best for you and to get well soon. About the Neurontin, it does not interfere with EMG test at all.  
  Comment Hello Dr., I have appreciated all of your advise in the past.
I went to the Neurologist Wednesday he does believe I have a Median Nerve lesion. He did a nerve conduction test and told me it did not show any concerns of permanent nerve damage or motor skill damage. He has me on Neurontin, I am up to 4x/300mg per day. I was told He does believe I have pain and that the nerve will take time to heal. I was very relieved to hear that and left his office feeling good, then when I got home I started thinking why did nothing show up when I have so much pain.
The pain is mostly in my finger index, middle, and ring finger. If I wait to long before I take the medicine I have a lot of discomfort in my elbow and lower arm.
The Doctor said, “be patient”. Those nerves heal an inch a Month.
I called the office back today and asked if he would send me for an MRI and he had the nurse tell me he would not OK it. I was hoping I would have someone tell me exactly what is happening in there.
Should I just give it time he wants me back in 2 Months.
Thank you in advance,
  Answer Thank you. I am pleased that you feel better. All the best  
poster later
by the same
I have post several times in the past and you have been very helpful. I currently am healing I hope from a puncture during a blood draw. I am concerned and have asked my Doctor about a tingling in my cheek that started shortly after the injury. It is not always there and changes to different areas of my left cheek. The elbow that was injured is my left elbow. It has been 5 months.

Is this something that can happen when you have an injury of this kind?

I have the physical therapist tell me everything is connected and as long as I take the Neurontin I am on regularly it is not as noticeable.

  Answer I cannot see a relationship between the problem at the elbow and the tingling in your cheek. I am not sure why do you have cheek tingling. It seems coincidental.
  Comment I got my injury to my nerve back at the end of March (blood draw, elbow). I have had a lot of different stages of healing, and strange feelings at different times. I get jabs and pains in my fingers but I also get jabs and pains in my toes. Do you think this is all a normal part of healing? I had an EMG in May and I was told it did not show any sign of Permanente damage.

Should I have another test done? I am on Neurontin 600 mgs three times a day. I get these pains if I go to long between doses.

Should I get another EMG?

Is this normal?

Should I see another Doctor?

  Answer I can understand the pain in the fingers but not the pains in the toes. Therefore, it would be good idea to consult another doctor before you proceed to another EMG.  
  Comment I have posted before and you have given me good advice. I the best advise you gave me was to see another Doctor. I did and was given diagnoses of Venipuncture RSD, are you at all familiar with this? I am hoping I have not waited to long to get the right Doctor. I have had two visits with Dr. who is in Florida and he has treated RSD in patients for 30 years. I feel I am getting the proper treatment although he has said that my type of RSD is the most vicious type to have. He has me on 4 medications and I am in Physical therapy and I am using a heat pad and feel somewhat better. I have stopped taking the Neurontin that was making me very tired all the time and that caused me to gain 20 lbs. in 8 months. I have a very scary health problem that might be with me for life.

I had told you and you asked me to keep you posted so I am doing that. I hope that if there are other patients out there that don't feel the Doctor understands their pain that they get other help and with someone that knows about RSD.

  Neck/Arm Nerve damage from Anesthesia Needle  
  Hello, I have a friend that was to undergo surgery about 5 weeks ago. In the course of having the anesthesia put into his neck, the anesthesiologist hit a nerve. My friend's arm became uncontrollable and through some very scary moments, the anesthesiologist succeeded in applying the full anesthesia -- but the surgery was canceled due to the immediately obvious consequences: right arm in severe pain, limp and no motor control. After 5 weeks, the pain is at a constant level - no change. He still has virtually no motor ability in his right arm. He describes what he feels this way: "It is like my arm is going to explode from pressure." He has the sensation of his arm being completely "inflated", though there is no inflation apparent on the outside. Multiple physicians have been consulted. Everyone has a "wait and see" conclusion, as this is such a rare thing, and none consulted have had any experience with this kind of incident. At this point in time, my friend lives with pain every second. He is looking for ideas -- directly or anonymously -- as to how he can 1) perhaps stimulate nerve regeneration, 2) expedite nerve regeneration, 3) any experiments.  
  Answer It is difficult to imagine exactly what happened, but in such instances, it is not uncommon that the nerve can get damaged as a result of the puncture or the injection. Nerve damage resulting from puncture or injection can take a long time to recover. In such cases I recommend seeing a neurologist to get an EMG and assess the amount of nerve(s) damage and then a Neurosurgeon who specializes in peripheral nerve surgery in particular. This will be useful to determine if any surgical intervention may be necessary, now, or after a certain period of time has elapsed to give the nerve enough time to heal on its own.
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