Electrodiagnostic Procedures at Arthritis & Sports
Electrodiagnostic procedures like EMGs and nerve conduction studies are important tools for physicians to assess nerve and muscle function. Because nerve damage can cause a range of symptoms that can be difficult to diagnosis, these electrodiagnostic procedures are important tools that help explain why you may be experiencing these symptoms.
We are excited to offer our patients access to quality EMGs and nerve conduction studies at our Sterling location. These electrodiagnostic procedures are performed in-house by Dr. J. Austin Underwood, our newest physician at Arthritis & Sports. In addition to nerve testing, Dr. Underwood specializes in sports medicine and rehabilitation medicine.
What are electrodiagnostic procedures?
“Electrodiagnostic testing is an important tool to help us diagnose how well your nerves and muscles are functioning and locate where any nerve or muscle problems are,” says Dr. Underwood. “At Arthritis and Sports, we can then use this information to help our patients receive the treatments they need.”
When we want to do something, like lift our phone off the table, our brain tells nerve cells in the spinal cord (called motor neurons) to send a message down a long, very thin extension of itself (called an axon) to the muscles needed to perform the activity. When the message reaches the muscle, a chemical is released that causes the muscle fibers to contract. Since each motor neuron only connects to a single muscle, several of these messages may need to be sent in unison to perform the action.
A nerve conduction study, also known as an NCS, measures how fast and how well the body’s electrical signals travel down these nerves. Alternatively, electromyography, also known as an EMG, looks at the individual muscles and how well they “turn on”. While these tests can be done separately, they are often done at the same time to see if your symptoms are caused by a muscle disorder or a nerve problem.
Why are these tests important?
Since some nerve and muscle issues may be difficult to diagnose, a physical exam and/or blood tests alone may not be enough to provide a diagnosis. EMGs and nerve conduction studies can detect abnormal muscle and/or nerve properties, allowing our providers to identify why a muscle may be weak or pinpoint exactly where a nerve blockage may be occurring.
You may need one (or both) of these tests if you have symptoms that indicate a muscle or nerve disorder, including:
tingling or numbness in arms, legs, hands, and/or feet
muscle pain, cramps, spasms, and/or twitching
certain types of limb pain
paralysis of any muscles
Our providers may also recommend diagnostic nerve studies to confirm or rule out various conditions, including:
Muscle disorders (such as muscular dystrophy or polymyositis)
Disorders of nerves outside the spinal cord (such as carpal tunnel syndrome or other entrapment neuropathies)
Diseases that affect the connection between the nerve and muscle (such as myasthenia gravis)
Disorders that affect the motor neurons in the brain or spinal cord (such as amyotrophic lateral sclerosis, also known as ALS)
Disorders or injuries that affect the nerve root (such as herniated discs or nerve compression)
Other conditions of the nerves or muscles
About Nerve Conduction Studies (NCS)
Nerve conduction studies measure how fast and how well your nerves can send electrical signals. This allows our providers to find damage or disease in the peripheral nervous system – a section of the body made up of all the nerves leading away from the brain and spinal cord (and the smaller nerves that branch from those nerves).
When performing nerve conduction studies, your physician will place one or more small electrodes on your skin. These electrodes send quick, mild electrical impulses that activate the nerves one at a time, so that the physician can see the nerve or muscle’s response. This allows the physician to compare the response time between the signal and muscle reaction to what is considered “normal” to determine if there is an issue.
The nerve stimulation only causes a tingling sensation, with no pain involved in the testing.
About Electromyography (EMG)
Electromyography is a diagnostic procedure that allows our physicians to assess the health of muscles and the nerve cells that control when they contract. By measuring the electrical activity in the muscles, our physicians can determine if they are responding to nerve signals properly.
While NCSs use electrodes placed on the skin to measure activity, EMGs require the physician to insert a micro-needle into the muscle being tested. This may cause slight pain or discomfort when inserted, but is relieved once the needle is taken out. Your physician will measure the muscle activity at rest and when activate (ex. they may ask you to relax your arm straight, then ask you to bend your elbow while squeezing your arm).
How do I prepare for testing?
There are no activity restrictions before or after either EMGs or NCSs. However, it is important to not apply any body lotion in the area being tested.
Each study is designed for your symptoms so the length of the test can vary. However, they usually take between 30 to 60 minutes.
The physician performing your test may be able to explain some of your test results during your visit, but this is not always possible. Because these tests are highly technical and often need to be thoroughly reviewed, you may need to schedule a follow-up visit to discuss your condition, treatment options, and any further testing needs.
Are there any special precautions for these tests?
Your physician will make every effort to minimize any discomfort you may feel during these tests.
Be sure to inform the physician if you:
are taking blood-thinning medications, such as Coumadin
have a cardiac pacemaker or other implanted stimulators
These require the physician to determine if the testing procedure ordered is suitable at that time.
At Arthritis & Sports, our focus is on providing quality care for all of your orthopaedic needs under one roof. Since EMGs and NCSs are diagnostic medical studies, a referral from a physician or appropriate healthcare professional may be required by your insurance carrier. If you have received a referral from your physician or healthcare provider, you can schedule your appointment at Arthritis & Sports in person or by phone at 703-444-5000.