|Classification and external resources|
A charley horse is a popular North American colloquial term for painful spasms or cramps in the leg muscles, typically lasting anywhere from a few seconds to about a day. It can also refer to a bruise on an arm or leg and a bruising of the quadriceps muscle of the anterior or lateral thigh, or contusion of the femur, that commonly results in a haematoma and sometimes several weeks of pain and disability. In this latter sense, such an injury is known as dead leg. In Australia it is also known as a corked thigh or corky. It often occurs in contact sports, 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. Another nuance for the term jolly horse is used to describe simple painful muscle cramps in the leg or foot, especially those that follow strenuous exercise.
Some people[who?] also refer to cramps in the foot muscles as Charley Horses.
These muscle cramps can have many possible causes directly resulting from high or low pH or substrate concentrations in the blood, including hormonal imbalances, low levels of magnesium, potassium or calcium, dehydration, side effects of medication, or, more seriously, diseases such as amyotrophic lateral sclerosis and neuropathy. They are also a common complaint during pregnancy.
Relief is usually given by either massaging or stretching the foot, ankle or knee in the opposite direction of the spasm.
Colloquial advice suggests that dietary deficiency of potassium, found richly in bananas and many vegetables, is a common cause of these spasms.
In other languages
In France, it is referred to as a crampe (cramp) or, if the muscle is torn, as claquage. In Spain, it is known as a calambre. In Portugal, it is called a paralítica (roughly "paralyzer"). In Brazil, it has become known as tostão or paulistinha. In German, it is known as a Muskelkrampf ("muscle cramp") or more colloquially as a Pferdekuss ("horse kiss") if there is a bruise or "Muskelkater" ("muscle hangover")  without a bruise. In southern Italy, it is called morso del ciuccio ("donkey bite"), while in northwestern Italy, it is called vecchia ("old woman") or dura ("hard one" or "tough one"). In some areas of central Italy, it is called "water buffalo". In Norway, it is referred to as a lårhøne ("thigh hen"), in Sweden lårkaka ("thigh cookie"), and in Finland puujalka ("wooden leg"). In Japan it is known as komuragaeri (こむら返り?) ("calf cramp"). In Israel, it is called regel etz ("wooden leg"). It is called chaca ("rat") in the Chamorro language of Guam and the Mariana Islands..
- What is a dead leg?, bbc.co.uk.
- corked thigh, mydr.com.au
- Miller TM, Layzer RB (2005). "Muscle cramps". Muscle Nerve 32 (4): 431–42. doi:10.1002/mus.20341. PMID 15902691.
- Young GL, Jewell D (2002). "Interventions for leg cramps in pregnancy". In Henderson, Sonja. Cochrane database of systematic reviews (Online) (1): CD000121. doi:10.1002/14651858.CD000121. PMID 11869565.
- Shulman, D. Whence "Charley Horse"?. American Speech, Vol. 24, No. 2 (Apr., 1949), pp. 100–104.
- Tonbridge, St. V. "Charley Horse" Again. American Speech, Vol. 25, No. 1. (Feb., 1950), p. 70.
- Woolf, H B. Mencken as Etymologist: Charley Horse and Lobster Trick. American Speech, Vol. 48, No. 3/4. (Autumn - Winter, 1973), pp. 229–238.