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Electromyography (EMG) Explained

 

Electromyography (EMG)

EMG stands for Electromyography. It is a medical test used to check how well your muscles and the nerves that control them are working.

What it does

EMG measures the electrical activity in your muscles. When nerves send signals to muscles, they create tiny electrical impulses—EMG records these.

Why doctors use it

Doctors may recommend EMG if you have symptoms like:

  • Muscle weakness
  • Numbness or tingling
  • Muscle pain or cramping
  • Suspected nerve disorders

It helps diagnose conditions such as:

  • Carpal Tunnel Syndrome
  • Amyotrophic Lateral Sclerosis (ALS)
  • Peripheral Neuropathy

How it’s done

  1. Nerve conduction study (NCS) – small electrical pulses are applied to test nerve signals
  2. Needle EMG – a thin needle electrode is inserted into muscles to record activity

Does it hurt?

  • You might feel mild discomfort (like a quick pinch or muscle soreness)
  • Most people tolerate it well

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