EMG and Nerve Conduction Study

Electrical testing that shows whether a nerve is genuinely damaged, which nerve it is, and how badly.

What it is

An MRI shows anatomy. It cannot tell you whether a nerve is actually working. EMG and nerve conduction studies measure function directly, which is why they resolve questions imaging cannot — such as whether arm symptoms come from the neck or the wrist.

What we use it for

• Separating cervical radiculopathy from carpal tunnel syndrome
• Confirming and grading peripheral neuropathy
• Documenting objective nerve injury after an accident or work injury
• Deciding whether weakness is neurological or from pain inhibition

What to expect

• Two parts: small electrical pulses along the nerve, then a fine needle electrode in selected muscles.
• The pulses feel like a static shock. The needle portion is uncomfortable but brief.
• Allow about 45 minutes. No sedation, and you can drive yourself.
• Do not use lotion on the skin that morning, and tell us if you take a blood thinner or have a pacemaker.

Risks

This is a test rather than a treatment and its risks are minimal. The needle portion causes brief discomfort and occasionally a small bruise. Tell us in advance if you take anticoagulants, if you have a pacemaker or implanted defibrillator, or if you have lymphoedema in a limb — each changes how or whether parts of the study are done. Do not apply lotion or cream to the skin that morning, as it interferes with the surface electrodes.

To discuss whether this is appropriate for you, call (314) 310-5577 or request an appointment.

How we judge whether it worked

The value is that it measures function rather than appearance. Imaging can show a compressed nerve that is working perfectly and can look normal beside a nerve that is not.

It also grades severity, which changes decisions. Mild compression with intact motor responses is a conservative problem; established axonal loss with muscle wasting is a surgical referral, and the distinction is not visible any other way.