In medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....

 a spasm is a sudden, involuntary contraction
Muscle contraction
Muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. While under tension, the muscle may lengthen, shorten, or remain the same...

 of a muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...

, a group of muscles, or a hollow organ
Organ (anatomy)
In biology, an organ is a collection of tissues joined in structural unit to serve a common function. Usually there is a main tissue and sporadic tissues . The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are...

, or a similarly sudden contraction of an orifice
An orifice is any opening, mouth, hole or vent, as of a pipe, plate, or a body.* Body orifice* Orifice plate* Calibrated orifice* Nozzle* Back Orifice-See also:* Choked flow* Needle valve* Venturi effect* Flow measurement...

. It is sometimes accompanied by a sudden burst of pain
Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...

, 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
Dystonia is a neurological movement disorder, in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The disorder may be hereditary or caused by other factors such as birth-related or other physical trauma, infection, poisoning or reaction to...


Hypertonic muscle spasms
Hypertonia a condition marked by an abnormal increase in muscle tension and a reduced ability of a muscle to stretch. It is caused by lesions to upper motor neurons in the central nervous system, which carry information from the central nervous system to the muscles and control posture, muscle...

 are caused by excessive muscle tone
Muscle tone
In physiology, medicine, and anatomy, muscle tone is the continuous and passive partial contraction of the muscles, or the muscle’s resistance to passive stretch during resting state. It helps maintain posture, and it declines during REM sleep.-Purpose:Unconscious nerve impulses maintain the...

 or residual tension in a resting muscle – the amount of contraction that remains when a muscle is not actively working. Hypertonia 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.

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
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...

, activity, emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...

, stress, or anxiety
Anxiety is a psychological and physiological state characterized by somatic, emotional, cognitive, and behavioral components. The root meaning of the word anxiety is 'to vex or trouble'; in either presence or absence of psychological stress, anxiety can create feelings of fear, worry, uneasiness,...


A subtype of spasms is colic
Colic is a form of pain which starts and stops abruptly. Types include:*Baby colic, a condition, usually in infants, characterized by incessant crying*Renal colic, a pain in the flank, characteristic of kidney stones...

, an episodic pain due to spasms of smooth muscle
Smooth muscle
Smooth muscle is an involuntary non-striated muscle. It is divided into two sub-groups; the single-unit and multiunit smooth muscle. Within single-unit smooth muscle tissues, the autonomic nervous system innervates a single cell within a sheet or bundle and the action potential is propagated by...

 in a particular organ (e.g. the bile duct
Bile duct
A bile duct is any of a number of long tube-like structures that carry bile.Bile, required for the digestion of food, is excreted by the liver into passages that carry bile toward the hepatic duct, which joins with the cystic duct to form the common bile duct, which opens into the intestine.The...

). A characteristic of colic is the sensation of having to move about, and the pain may induce nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...

 or vomiting
Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...

 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, which can cause tearing of tendons and ligaments.

Hysterical strength
Hysterical strength
Hysterical strength describes displays of extreme strength by humans, beyond what is believed to be normal. It is a speculative term that is not recognized in medical academia; the concept has only a small body of anecdotal evidence to support it....

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

Amongst causes of spasms are insufficient hydration, muscle overload, and absence of electrolytes.

See also

  • Antispasmodic
    An antispasmodic is a drug or a herb that suppresses muscle spasms.-Smooth muscle spasm:One type of antispasmodics is used for smooth muscle contraction, especially in tubular organs of the gastrointestinal tract...

  • Blepharospasm
    A blepharospasm , is any abnormal contraction or twitch of the eyelid....

  • Cadaveric spasm
    Cadaveric spasm
    Cadaveric spasm, also known as instantaneous rigor, cataleptic rigidity, or instantaneous rigidity, is a rare form of muscular stiffening that occurs at the moment of death, persists into the period of rigor mortis and can be mistaken for rigor mortis...

  • Cramp
    Cramps are unpleasant, often painful sensations caused by muscle contraction or over shortening. Common causes of skeletal muscle cramps include muscle fatigue, low sodium, and low potassium...

  • Cricopharyngeal spasm
    Cricopharyngeal Spasm
    Cricopharyngeal spasms occur in the cricopharyngeus muscle of the pharynx. These spasms are frequently misunderstood by the patient to be cancer due to the 'lump in the throat' feeling that is symptomatic of this syndrome. In practice, real lumps in the throat, such as a cancer, are generally not...

  • Ejaculation
    Ejaculation is the ejecting of semen from the male reproductory tract, and is usually accompanied by orgasm. It is usually the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. In rare cases ejaculation occurs because of prostatic disease...

  • Myoclonus
    Myoclonus is brief, involuntary twitching of a muscle or a group of muscles. It describes a medical sign and, generally, is not a diagnosis of a disease. Brief twitches are perfectly normal. The myoclonic twitches are usually caused by sudden muscle contractions; they also can result from brief...

  • Neck spasm
    Neck spasm
    -Causes of neck spasm:The possible causes of neck spasms include:* Anxiety* Muscle strain* Tension* Tetanus* Spasmodic torticollis* Stress* Viral infection* Whiplash injury* or other causes of spasm...

  • Orgasm
    Orgasm is the peak of the plateau phase of the sexual response cycle, characterized by an intense sensation of pleasure...

  • Seizure
    An epileptic seizure, occasionally referred to as a fit, is defined as a transient symptom of "abnormal excessive or synchronous neuronal activity in the brain". The outward effect can be as dramatic as a wild thrashing movement or as mild as a brief loss of awareness...

  • Spasmodic dysphonia
    Spasmodic dysphonia
    Spasmodic dysphonia is a voice disorder characterized by involuntary movements of one or more muscles of the larynx during speech.- Types of spasmodic dysphonia :...

External links

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