Electromyography and Electroneuromyography (EMG/ENMG)

Electroneuromyography (ENMG) is a neurological investigation that evaluates the function of peripheral nerves and the muscles they control. Depending on clinical indications, it may include:

• Nerve conduction studies (NCS/ENG) — assess how electrical impulses travel along the nerves.
• Electromyography (EMG) — measures muscle electrical activity at rest and during contraction using a fine needle electrode.

In some cases, only nerve conduction studies are required, while in others EMG is added for a comprehensive evaluation of the nerve–muscle unit.

When EMG/ENMG is recommended

• in patients with muscle weakness, loss of strength, or unexplained fatigue,
• in the presence of numbness, tingling, or limb pain,
• for diagnosing peripheral neuropathies (diabetic, inflammatory, toxic),
• in radiculopathies (nerve root involvement due to disc herniation or spinal disorders),
• in compression neuropathies (e.g. carpal tunnel syndrome),
• to differentiate muscle disorders (myopathies) from neurological diseases.

How the investigation is performed

• ENG/NCS: mild electrical stimuli are applied to the nerve, and responses are recorded from the muscle or along the nerve pathway.
• EMG: a fine needle electrode is inserted into the muscle to record activity at rest and during contraction.
• The physician selects the appropriate protocol based on symptoms and clinical suspicion.

Benefits for the patient

EMG/ENMG are safe, accurate, and essential tools for diagnosing neuromuscular disorders. They allow:

• early detection of polyneuropathies and radiculopathies,
• confirmation and grading of nerve compression,
• differentiation between nerve and muscle diseases,
• guidance toward a personalized treatment plan.