By David Doward, MD with Ehren Allen, DPT
What is Electromyography or EMG?
Electromyography or EMG is a test that doctors use to tell if a muscle is working properly. The brain tells muscle when and how much to move. When the brain tells a muscle to move, it sends a message to the muscle using nerves. The nerve delivers the message using electrical impulses. When these impulses reach the muscle, they tell the muscle to tighten or contract. With an EMG test, a tiny needle is inserted into a muscle to detect how many electrical impulses are getting to the muscle.
What is a Nerve Conduction Study (NCV)?
A Nerve Conduction Study (NCV) is a test doctors use to see how well a nerve works. Typically, electrical impulses travel really quickly along nerves. With an NCV test, a small pad called an electrode is placed on the skin in 2 places. The pads are placed over the area where the nerve lies. An electrical impulse is sent through one of the pads to stimulate the nerve. The other pad detects how long it takes for the impulse to reach it through the nerve. This allows doctors to determine the speed or velocity that the nerve conducts electrical messages. The nerve conduction velocity or speed can help determine the health of the nerve.
Why Would I Need an EMG or NCV Test?
EMG and NCV tests assist to rule out a variety of nerve-related issues. According to Dr. David Doward, the most common reason he performs EMG and NCV tests is when Carpal Tunnel Syndrome is suspected. Carpal Tunnel Syndrome is a condition that affects a nerve in the wrist and hand. But, issues in the neck can cause similar issues. By testing the nerve function, he can rule out certain nerve areas and determine the true cause of the symptoms.
Many other conditions may require an EMG and NCV test. Some of these include:
- Cervical Radiculopathy
- Lumbar Radiculopathy
- Carpal Tunnel Syndrome
- Cubital Tunnel Syndrome
- Guillain Barre’ Syndrome
- Multiple Sclerosis
Does an EMG or NCV Test Hurt?
There are rumors that EMG and NCV tests are painful. This is typically not the case. There may be discomfort, but most people do not experience a lot of pain. The needle can cause some discomfort, but it usually goes away immediately after the test. The electrical impulse with the NCV test may cause mild discomfort, but the impulse is not too intense.
Are There Any Risks with an EMG or NCV Test?
There are very slight risks with EMG and NCV tests. As with any needle, there is a slight risk of bleeding or infection. Tell the doctor if you have any internal devices such as a pacemaker or internal defibrillator, as they may have to take precautions.
Where Do I Get an EMG or NCV Test?
The Physical Medicine and Rehabilitation Physicians at the Jacksonville Orthopedic Institute are experts in performing EMG and NCV Tests. They also specialize in treating spinal issues using non-surgical interventions. If you have spine or nerve issues, JOI has the answers for you!
If you would like to learn more about Nerve Conduction Studies, this video may help.
To schedule an appointment in our offices or with telemedicine, call 904-JOI-2000 or click the link below.