Did you know that your body is an electrical generator? Nerves and muscles create electrical signals that deliver messages to and from your brain. Sensory nerves deliver information about your surroundings to the brain. Motor nerves deliver signals from the brain to activate your muscles.
Injuries or diseases that affect nerves and muscles can slow or halt the movement of these electrical signals. If you have pain, weakness or numbness in your back, neck or hands, measuring the speed and degree of electrical activity in your muscles and nerves can help your doctor make a proper diagnosis. This process is called electrodiagnostic testing.
Two tests are commonly used:
Nerve conduction studies (NCS)
These tests are usually administered by a neurologist (a doctor who specializes in the study of the nerves) or a physiatrist (a specialist in rehabilitation medicine). The tests can be done in less than an hour (AAOS, 2015).
When would my doctor consider an electrodiagnostic (EDX) study?
This study is considered when the reason for pain or tingling or weakness is not clear. This study can also be used to determine the severity of a nerve injury or how badly a nerve is being pinched in the neck or back. Occasionally other conditions can mimick a pinched nerve in the back or neck. Electrodiagnostic studies can also help determine if other conditions are occurring.
What should my doctor know about me to determine if I should have an EDX?
The doctor performing the electrodiagnostic test will ask questions about the nature of your pain, tingling and weakness. This will help them determine which nerves and muscles to test. The physician may also ask questions about other conditions which may affect the nerves and muscles, such as diabetes and thyroid problems. Your doctor should know if you have ever had a neck or back surgery.
Are there any reasons I should not have an EDX study?
If you are on blood thinning medications, such as aspirin, plavix, heparin or warfarin (Coumadin), the physician may not perform certain portions of the test. If that information is absolutely necessary, you may be asked to stop blood thinning medication prior to the electrodiagnostic test. If you have a pacemaker or similar device, certain portions of the test may not be able to performed.
Nerve conduction studies
The doctor performs these studies by placing sensors over nerves in the arms and legs and then stimulating those nerves with small electric sensations. The doctor is able to see how fast or slow nerves are functioning. Comparisons are made to averages to see if see the nerves are working properly.
EMG is performed by placing small needles in the muscles of the arm, leg or back to directly evaluate the electrical activity caused by a muscle contraction. EMG allows the physician to evaluate how well muscles are functioning. In addition, the EMG study can help determine if muscles are receiving the proper signal from nerves.
It’s not always possible to prevent spine and nerve conditions. The following suggestions can play a key role in protecting your back:
- Exercise regularly. This is the most important thing you can do for your overall health as well as for your back. Pay special attention to your core muscles — the muscles in your abdomen and lower back that are essential for proper posture and alignment. Ask your doctor to recommend specific activities.
- Maintain proper posture when you sit. Choose a seat with good lower back support, arm rests and a swivel base. Consider placing a pillow or rolled towel in the small of your back to maintain its normal curve. Keep your knees and hips level.
- Use good body mechanics. If you stand for long periods, rest one foot on a stool or small box from time to time. When you lift something heavy, let your lower extremities do the work. Move straight up and down. Keep your back straight and bend only at the knees. Hold the load close to your body. Avoid lifting and twisting simultaneously. Find a lifting partner if the object is heavy or awkward.