Approach to the patient with muscle weakness
- Author
- Marc L Miller, MD
Marc L Miller, MD
- Clinical Assistant Professor of Medicine
- Tufts University School of Medicine
- Section Editors
- Ira N Targoff, MD
Ira N Targoff, MD
- Section Editor — Muscle Disease
- Professor of Medicine, Section of Rheumatology
- University of Oklahoma Health Sciences Center
- Jeremy M Shefner, MD, PhD
Jeremy M Shefner, MD, PhD
- Section Editor — Neuromuscular Disease
- Professor and Chair of Neurology, Barrow Neurological Institute
- Professor of Neurology, University of Arizona, Phoenix
- Clinical Professor of Neurology, Creighton University
- Deputy Editor
- Monica Ramirez Curtis, MD, MPH
Monica Ramirez Curtis, MD, MPH
- Deputy Editor — Rheumatology
- Instructor of Medicine, Part-time
- Harvard Medical School
INTRODUCTION
The evaluation of the patient presenting with a complaint of "weakness" involves three steps:
●Distinguishing true muscle weakness from lassitude 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".)
Subscribers log in here
To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:Literature review current through: Jun 2017. | This topic last updated: Jun 13, 2017.The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.References- Medical Research Council. Aids to the Examination of the Peripheral Nervous System. Memorandum no. 45. London, Her Majesty's Stationery Office, 1981.
- Rosow LK, Amato AA. The Role of Electrodiagnostic Testing, Imaging, and Muscle Biopsy in the Investigation of Muscle Disease. Continuum (Minneap Minn) 2016; 22:1787.
- Warren JD, Blumbergs PC, Thompson PD. Rhabdomyolysis: a review. Muscle Nerve 2002; 25:332.
- Dalakas MC. Inflammatory Muscle Diseases. N Engl J Med 2015; 373:393.
- Targoff IN. Laboratory testing in the diagnosis and management of idiopathic inflammatory myopathies. Rheum Dis Clin North Am 2002; 28:859.
Top- INTRODUCTION
- DISTINGUISHING TRUE MUSCLE WEAKNESS FROM LASSITUDE
- History
- Physical examination
- LOCALIZING THE SITE OF THE LESION
- Distribution of weakness as a guide to localizing the lesion
- DETERMINING THE CAUSE OF THE LESION
- Sites of lesions
- - Lesions of upper motor neurons
- - Anterior horn cell lesions
- - Lesions of the peripheral nervous system
- - Myopathy
- Clinical investigations
- - Laboratory studies
- - Electrophysiologic studies
- - Magnetic resonance imaging
- - Muscle biopsy
- - Genetic testing
- RESPIRATORY MUSCLE WEAKNESS
- SUMMARY
- REFERENCES