Electromyography is a test used to evaluate the performance of nerves and muscles of the body. The test is performed by using an instrument named electromyography. This technology records the electrical potential generated by muscle fibers when the muscle tissue contracts. It also records the electrical signal produced along the nerve to analyze nerve potentials, conduction speed, and quality.

Why should an EMG be performed?

EMG is used to diagnose neuromuscular conditions. Thus, any condition resulting in abnormal function of peripheral nerves, muscle, or junction between the nerve and muscle may be evaluated using this tool.

What disorders may be analyzed by EMG?

• Axillary nerve dysfunction
• Becker's muscular dystrophy
• Brachial plexopathy
• Carpal tunnel syndrome
• Cervical spondylosis
• Charcot-Marie-Tooth disease
• Common peroneal nerve dysfunction
• Denervation (reduced nervous stimulation)
• Dermatomyositis
• Duchenne muscular dystrophy
• Facioscapulohumeral muscular dystrophy (Landouzy-Dejerine)
• Familial periodic paralysis
• Femoral nerve dysfunction
• Friedreich's ataxia
• Guillain-Barre
• Lambert-Eaton Syndrome
• Mononeuritis multiplex
• Mononeuropathy
• Motor neuron disease
• Myasthenia gravis
• Myopathy
• Neuromyotonia
• Peripheral neuropathy
• Poliomyelitis
• Polymyositis
• Radial nerve dysfunction
• Sciatic nerve dysfunction
• Sensorimotor polyneuropathy
• Shy-Drager syndrome
• Spinal stenosis
• Thyrotoxic periodic paralysis
• Tibial nerve dysfunction
• Ulnar nerve dysfunction
• and other medical conditions


How do I prepare for my EMG evaluation?

Part of the study may involve small needles that are inserted into the muscle. Mild electrical shocks are given to stimulate the nerve. You may experience some discomfort during the tests, but they generally are not painful. These tests take less than one hour.

To prepare for an EMG, please do the following:

• Bathe or shower on the day of the test. Wash arms and legs well to remove body oils. Don't use lotion, bath oils or creams

• Wear comfortable, loose-fitting clothes

• Eat your normal meals (but you may wish to avoid tobacco or caffeine for a few hours prior to your test)

• Bring a list of medications you are taking, especially any blood thinners

Tell Dr. Klos if you:

...bruise easily
...have hemophilia
...have a pacemaker
...have a skin infection

You may take over-the-counter pain medication if you wish, as they do not affect test results.