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HSS Journal

, Volume 2, Issue 1, pp 19–21 | Cite as

EMG: Myths and Facts

  • Joseph Feinberg
Original Article

Electrodiagnostic testing, more commonly known as the EMG test, to many is a “black box.” It is a commonly ordered test that can provide very definitive information that is often not well understood. A large amount of information is usually provided, yet most clinicians rely primarily on the concluding statements, which may or may not be well substantiated. Added insight into this test demands understanding some basic facts about the “EMG” test and dispelling some of the myths.

The timing for ordering an EMG study

One of the most common myths about EMG tests is that one must wait 2–3 weeks following a nerve injury before reliable information can be obtained. It is true that the degree of muscle denervation that occurs after nerve injury can not be determined until Wallerian degeneration is complete and this can take as short as 1 week or as long as 4 weeks [1]. This is a length-dependent process so that the longer the length of the injured axon, the longer Wallerian degeneration will...

Keywords

Motor Unit Nerve Conduction Study Axonal Regeneration Neurological Recovery Motor Unit Recruitment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Hospital for Special Surgery 2006

Authors and Affiliations

  1. 1.Physiatry Department at the Hospital for Special SurgeryHospital for Special SurgeryNew YorkUSA

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