How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dr. Frank Your Own Question
Dr. Frank
Dr. Frank, Board Certified Physician
Category: Neurology
Satisfied Customers: 9000
Experience:  Board certified general Adult Neurologist, with experience in experimental neuroimaging and neurodiagnostics.
Type Your Neurology Question Here...
Dr. Frank is online now
A new question is answered every 9 seconds

Will an EMG find lower extremities weakness , MRI showed no

This answer was rated:

Will an EMG find lower extremities weakness , MRI showed no blockage in spine.

Hello. an EMG is a neurodiagnostic test, it looks at nerve function a few different ways, and tests the nerve as if it were a wire, looking at the insulation (conduction velocity) efficiency, and the health of the nerve axon itself (motor or sensory amplitudes) by sending a little electrical impulse down the nerve. Diseases of the nerve, either demyelinating or axonal will show problems on this part of the test, so neuropathies from a variety of causes, diabetes, myeloma, whatever, will be found on this part of the test,. The second part is the needle examination, which is able to look at the nerve muscle interface, and nerve or muscle diseases will be seen on this test.

So the answer is that the EMG is the way to assess nerve function, especially if you are weak and your back does not seem to be involved. Please get back to me with questions, and I will return to reply. Dr Frank T.

Customer: replied 4 years ago.

Which area of nerve bundle should accesed for lower body weakness during EMG WITH nO BLOCKAGE OF SPINE

Hi. I saw there was no blockage of the spine. that doesn't mean you cannot have a disease of the nerve itself, it is called Neuropathy. And it comes about because the nerve has a disease within it, that makes it difficult for it to work. There is two types of damage the nerve can have, it can lose its insulation , or the inside of the nerve can lose its jelly for transport of electrical impulses. They do different things to the nerve.

Your question is ,"what area or nerve bundle should be looked at for lower body weakness:" Well that depends on the specific weakness. If it is your lower leg, the ability to get up on your toes, or walk on your heels, then that is the sciatic nerve, which divides into the tibial and common peroneal nerves. If you have problems lifting your straight leg off the bed when laying on your back, then that is the femoral nerve on the front of your thigh.

There are motor or strength parts and sensory parts to these nerves, so you have to look at both parts, are you numb anywhere, or just weak? let me know. Dr Frank T

Customer: replied 4 years ago.

just weak from waste down

Customer: replied 4 years ago.

total lower extremity

Ok. So you are saying that symmetrically you are weak and it is not more in your lower legs than in your thighs. correct? everything is weak, and again do you have numbness? that is really important to decide if the entire nerve is involved (motor and sensory) or just the motor part, and that lowers the possibilities.

Also do you have pain in your muscles? especially if you squeeze them? You could have a muscle problem, or something called a neuromuscular problem. Again the EMG will be able to tell the neurologist about that as a possibility. Did you have a viral disease, a fever about 2 weeks before this all started? or is this a chronic problem? Let me know and I can give you some ideas, it might not be correct as I cannot examen you, but I can give you some choices maybe. Dr Frank T.

Dr. Frank and other Neurology Specialists are ready to help you

Are you on any medications? for high cholesterol?