View source for Spasm

{{SignSymptom infobox |
  Name        = Muscle spasm |
  ICD10       = {{ICD10|R|25|2|r|25}} |
  ICD9        = {{ICD9|728.85}} |
  MeshID      = D013035 |
}}
{{for|the 1993 metal album|Spasm (album)}}
{{redirect|Spasmodic|the British literary movement|Spasmodic poets}}

A '''spasm''' is a sudden, involuntary contraction of a [[muscle]], a group of muscles,<ref>{{DorlandsDict|seven/000098803|spasm}}</ref> or a hollow [[Organ (anatomy)|organ]], or a similarly sudden [[contraction]] of an [[orifice]].  It is sometimes accompanied by a sudden burst of [[pain]], but is usually harmless and ceases after a few minutes. Spasmodic muscle contraction may also be due to a large number of medical conditions, including the [[dystonia]]s.

“Hypertonic muscle spasm”, also known as hypertonus, means “too much muscle tone”, and is unfortunately very common. [Muscle tone is the residual tension in a resting muscle – the amount of contraction that remains when a muscle is not actively working.] Hypertonus is beyond conscious control, it does not always produce direct awareness of its presence, and it surfaces in many ways not normally associated with muscle. What may appear as skeletal, circulatory, nerve, or inflammatory distress usually begins with hypertonic muscle spasm, a condition caused by the interruption of nerve feedback loops between muscle and brain.

We tend to think of “spasm” as a cramp or tic, usually temporary and caused by lack of circulation.  But true hypertonic spasm is caused by malfunctioning feedback nerves, is much more serious, and is permanent unless treated. Simply put, the hypertonic muscle is muscle tone run amok – the muscles are unable to relax.

By extension, a spasm is a temporary burst of [[energy]], [[Physical_activity|activity]], [[emotion]], [[stress (biological)|stress]], or [[anxiety]].

A subtype of spasms is [[colic]], an episodic pain due to spasms of [[smooth muscle]] in a particular organ (e.g. the [[bile duct]]). A characteristic of colic is the sensation of having to move about, and the pain may induce [[nausea]] or [[vomiting]] if severe. Series of spasms or permanent spasms are called a spasmism.

In very severe cases, the spasm can induce muscular contractions that are more forceful than the sufferer could generate under normal circumstances. This can lead to torn tendons and ligaments.

[[Hysterical strength]] is argued to be a type of spasm induced by the brain under extreme circumstances.


Spasms can be caused by insufficient hydration, muscle overload or absence of some minerals (such as magnesium).
 
==See also==
{{col-begin}}{{col-break}}
* [[Antispasmodic]]
* [[Blepharospasm]]
* [[Cadaveric spasm]]
* [[Cramp]]
* [[Cricopharyngeal spasm]] {{nb10}}
{{col-break}}
* [[Myoclonus]]
* [[Neck spasm]]
* [[Orgasm]]
* [[Seizure]]
* [[Spasmodic dysphonia]]
{{col-end}}

==Notes==
{{reflist}}

==External links==
{{wiktionary|spasm}}
* [http://www.nlm.nih.gov/medlineplus/ency/article/003193.htm NIH Medical Encyclopedia] 
* [http://health.howstuffworks.com/question223.htm How Stuff Works]


{{Nervous and musculoskeletal system symptoms and signs}}
{{Myopathy}}
[[Category:Medical signs]]
[[Category:Symptoms and signs: Nervous and musculoskeletal systems]]

{{med-sign-stub}}

[[bs:Mišićni spazam]]
[[cs:Křeč]]
[[de:Krampf]]
[[es:Espasmo muscular]]
[[fa:تنجش]]
[[fr:Spasme]]
[[it:Spasmo]]
[[lt:Spazmas]]
[[ja:痙攣]]
[[pl:Kurcz]]
[[pt:Espasmo]]
[[ru:Спазм]]
[[sr:Мишићни спазам]]
[[fi:Spasmi]]
[[sv:Spasm]]
[[tl:Pasma]]
[[uk:Спазм]]
[[Category:2Fix]]