Electromyography (EMG) measures and records the electrical activity of a muscle. The test can record a muscle's electrical activity at rest or during a muscle contraction.

An EMG is often done with nerve conduction studies. These studies can analyze the electrical activity in your nerves.

EMG of the Shoulder
EMG shoulder 2
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EMG is most often done to:

  • Aid in diagnosing the source of pain, cramping, or weakness
  • Differentiate between true muscle weakness and limitations due to pain
  • Determine if muscles and nerves are working properly
  • Distinguish between muscle and nerve disorders