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Approach to the patient with muscle weakness

Marc L Miller, MD
Section Editors
Ira N Targoff, MD
Jeremy M Shefner, MD, PhD
Deputy Editor
Monica Ramirez Curtis, MD, MPH


The evaluation of the patient presenting with a complaint of “weakness” involves three steps:

Distinguishing true muscle weakness from asthenia or motor impairment not due to loss of muscle power

Localizing, within the neuromuscular system, the site of the lesion that is producing weakness

Determining the cause of the lesion

This topic will review the approach to the patient with muscle weakness by addressing these three issues. The specific tests used to assess muscle weakness are discussed separately, as are the clinical manifestations and evaluation of respiratory muscle weakness. (See "Muscle examination in the evaluation of weakness" and "Respiratory muscle weakness due to neuromuscular disease: Clinical manifestations and evaluation".)


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Literature review current through: Apr 2017. | This topic last updated: Aug 28, 2015.
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