A charley horse is a painful involuntary cramp in the

legs A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element c ...

and/or foot, lasting anywhere from a few seconds to a day. The term formerly referred more commonly to bruising of the quadriceps muscle of the anterior or lateral thigh, or contusion of the femur, that commonly results in a

haematoma A hematoma, also spelled haematoma, or blood suffusion is a localized bleeding outside of blood vessels, due to either disease or trauma including injury or surgery and may involve blood continuing to seep from broken capillaries. A hematoma is b ...

and sometimes several weeks of pain and disability. In this latter sense, such an injury is known as dead leg. Dead legs and charley horses are two different types of injuries: A charley horse involves the muscles contracting without warning, and can last from a few seconds to a few days. A dead leg often occurs in

contact sport Contact sports are sports that emphasize or require physical contact between players. Some sports, such as mixed martial arts, are scored on impacting an opponent, while others, including rugby football, gridiron football and Australian rules f ...

s, such as football when an athlete suffers a knee (blunt trauma) to the lateral quadriceps causing a haematoma or temporary paresis and antalgic gait as a result of pain. Colloquially, taking a hit in the thigh area (thigh contusion) can also be referred to as a ''charley horse'' or even simply a ''charley.''

Cause

They have many possible causes directly resulting from high or low pH or substrate concentrations in the blood, including hormonal imbalances,

dehydration In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mil ...

, low levels of

magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...

potassium Potassium is the chemical element with the symbol K (from Neo-Latin '' kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmos ...

, or

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar ...

(evidence has been mixed), side effects of medication, or, more seriously, diseases such as

amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or Lou Gehrig's disease, is a neurodegenerative disease that results in the progressive loss of motor neurons that control voluntary muscles. ALS is the most commo ...

and

neuropathy Peripheral neuropathy, often shortened to neuropathy, is a general term describing disease affecting the peripheral nerves, meaning nerves beyond the brain and spinal cord. Damage to peripheral nerves may impair sensation, movement, gland, or o ...

. They are also a common complaint during

pregnancy Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins. Pregnancy usually occurs by sexual intercourse, but ...

Treatment

Relief is given by massaging or stretching the leg or foot in the opposite direction of the cramp. Relief also comes from standing up, which serves to counter the muscle-tightening signal.

Notes

References

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External links

* {{Nervous and musculoskeletal system symptoms and signs Muscular disorders Colloquial terms