Muscle function loss is when a muscle doesn't work or move normally. The medical term for complete loss of muscle function is paralysis.
Paralysis; Paresis; Loss of movement; Motor dysfunction
Loss of muscle function may be caused by:
A disease of the muscle itself (myopathy)
A disease of the nervous system: nerve damage (neuropathy), spinal cord or nerve injury, or brain damage (stroke or other brain injury)
The loss of muscle function after these types of events can be severe. Often it will not completely return, even with treatment.
Paralysis can be temporary or permanent. It can affect a small area (localized) or be widespread (generalized). It may affect one side (unilateral) or both sides (bilateral).
If the paralysis affects the lower half of the body and both legs it is called paraplegia. If it affects both arms and legs, it is called quadriplegia. If the paralysis affects the muscles that cause breathing, it is quickly life-threatening.
Diseases of the muscles that cause muscle-function loss include:
Congenital myopathies (usually due to a genetic disorder)
Sudden loss of muscle function is a medical emergency. Get medical help right away.
After you have received medical treatment, your doctor may recommend some of the following measures:
Follow your prescribed therapy.
If the nerves to your face or head are damaged, you may have difficulty chewing and swallowing or closing your eyes. In these cases, a soft diet may be recommended. You will also need some form of eye protection, such as a patch over the eye while you are asleep.
Long-term immobility can cause serious complications. Change positions often and take care of your skin. Range-of-motion exercises may help to maintain some muscle tone.
Griggs RC, Jozefowicz RF, Aminoff MJ. Approach to the patient with neurologic disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA. Saunders Elsevier; 2011:chap 403.
Mammen AL, Amato A. Statin myopathy: a review of recent progress. Curr Opin Rheum. 2010;22:644-650.
Joseph V. Campellone, M.D., Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.