True muscle weakness means that full effort does not produce a normal muscle contraction or movement. A voluntary muscle contraction is generated when the brain sends a signal through the spinal cord and nerves to a muscle. If the brain, the nervous system, the muscles or the connections are injured or effected by disease, the muscle will not contract normally and muscle weakness is the resultant symptom.
Chronic fatigue syndrome
Lou Gehrig’s disease
West Nile virus
Prolonged bed rest or immobilization
Diagnosis and Treatment
A thorough evaluation by a physician is indicated for muscle weakness. The evaluation will determine which muscles are affected, if muscle atrophy is present. Reflexes, sensation and muscle tone will be assessed. If further investigation is needed, the doctor may order diagnostic studies such as a CT scan, MRI, nerve conduction studies or electromyography as well as laboratory tests (drawing blood). The treatment will depend on the underlying problem and the severity of the symptoms.
Call your provider:
Whenever there is unexplained muscle weakness that is not due to periodic feelings of being tired or run down.
Any sudden onset of muscle weakness, such as being unable to move an arm or leg, or problems walking, standing or sitting upright
Any sudden onset of being unable to smile or make facial grimaces
Any chest muscle weakness resulting in difficulties breathing
Written by: JC Jones MA, RN Reviewed by: Paul Auerbach, MD Written: September 19, 2007 Last Updated: September 30, 2007 Published By:
Healthline Networks Inc.