Electroneuromyography – For the Diagnosis of Neuromuscular Diseases

In Which Cases Should We Consider Electroneuromyography (ENMG)?

Electroneuromyographic testing is used to diagnose peripheral and neuromuscular diseases, which can present with a variety of symptoms. Patients may experience:

• Sensory disturbances such as numbness, burning, tingling (pins and needles), primarily in the extremities—feet, hands, and toes;
• Abnormal fatigue, double vision, difficulty with swallowing and speech;
• Limited movement due to muscle weakness and/or muscle pain or atrophy, especially during physical activities (like climbing stairs, standing up from a chair).

For Which Conditions Is the Test Important?

Electroneuromyography evaluates the conductive function of peripheral nerves by stimulating them with electrical impulses. It helps assess:

• Neuropathies: brachial or lumbar plexus injuries of various origins (plexitis, radiculopathy, trauma), polyneuropathies (inherited or acquired), primary and secondary mononeuropathies (including diabetic, entrapment, or traumatic), etc.;
• Hereditary and acquired muscle pathologies (e.g., polymyositis, muscular dystrophy, various forms of hereditary myopathy);
• Neuromuscular transmission disorders (myasthenia gravis and myasthenic syndromes);
• Motor neuron diseases (e.g., amyotrophic lateral sclerosis, spinal muscular atrophy, etc.).

How Safe and Quick Is the Procedure?

ENMG is a widely used, safe, and non-harmful electrophysiological method. It is performed using a portable device connected to a computer. It assesses damage to the peripheral neuromotor system. Depending on the cause and location of the damage, symptoms and the scope, sequence, and duration of diagnostics may vary. The test itself typically lasts 20–40 minutes.

Does the Test Cause Discomfort, and How Often Can It Be Done?
During electroneurography, single-use adhesive surface electrodes are placed on the patient’s skin, and each nerve is stimulated with a low-amperage (100 mA) electric impulse at a few short points (lasting 0.2 ms). A ruler is used to measure nerve length over the tested segment to calculate the conduction speed of the nerve impulse. This method, despite minor discomfort, is well-tolerated.
Electromyography is performed using a fine (26G) needle-like disposable electrode inserted into the muscle to assess its electrical activity.

In most cases, one ENMG session is sufficient for diagnosis. However, in rare cases, follow-up monitoring may be needed after a minimum of 3 months.

Is a Doctor’s Referral Required for the Test?

Patients may be referred for ENMG by neurologists, family doctors, traumatologists, ophthalmologists, rehabilitation specialists, oncologists, rheumatologists, and other specialists.
Before the test, a neurological evaluation is necessary to determine symptom distribution, duration, and to create a personalized testing plan and scope.

Is Any Preparation Required for the Test?

No special preparation is needed. However, patients should wear loose clothing to allow easy access to limbs. The skin should be clean, free of calluses, and not covered with moisturizing creams. It should also be warm.
For facial nerve assessment, men should be clean-shaven.