Electroneuromyography is used to detect, localise and define nerve and muscle disorders.
Two different methods are used:
Electroneurography (ENG) investigates nerve conduction in the peripheral nerves (hands and feet). The nerves are stimulated using surface electrodes. Simultaneously, measurements are taken of the speed with which a nerve transmits electrical signals and the strength of nerve stimulation in the corresponding muscle. An ENG may, for example, be carried out in cases of polyneuropathy (damage to the peripheral nerves) or to localise and determine the extent of the damage when nerves have been injured or pinched (e.g. carpal tunnel syndrome).
Electromyography (EMG) is used to record electrical activity in a muscle. Thin needle electrodes are inserted directly into the patient's muscle. The activity of individual muscle fibres can thereby be determined. This examination method can, for example, determine whether muscle weakness is due to the muscle itself being diseased or whether the flow of information from the nerve to the muscle is disrupted. An EMG can also indicate the likelihood of recovery when muscles have become paralysed due to nerve damage or nerve inflammation. Nerve damage can also be localised by means of an EMG.