indications

Last reviewed 01/2018

Electromyographic responses from muscle can indicate the site and severity of nerve damage. Results depend on the completeness of injury and the time from injury to recording: after a complete nerve lesion, EMG changes may not develop for 2-3 weeks, and the investigation may have to be delayed to obtain worthwhile data.

A combination of nerve conduction studies and EMG can show the location of nerve damage, its severity, and gives some hint to prognosis.

EMG can be used in the diagnosis of and quantification of the extent of:

  • motor neurone disease
  • myasthenia gravis
  • neuropathy
  • myotonic dystrophy
  • polymyositis