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Cramp From Wikipedia, the free encyclopedia Jump to: navigation, search
For the heraldic device, see cramp (heraldry); for the band, see The Cramps
Cramps, (sometimes called charley horses in North America), are very unpleasant, often painful, sensations caused by contraction or over shortening of muscles. Cramps can be caused by cold, overexertion or low calciumlevel in blood (especially for adolescents where they need calcium forboth blood and bone maturing). Illness or poisoning can also causecramps, particularly in the stomach, which is referred to as colic if it fits particular characteristics.
[edit] CausesThere are six basic causes of cramping:[1] hyperflexion; hypoxia; exposure to large changes in temperature; dehydration; low blood salt; or low blood calcium. Muscle cramps may also be a symptom/complication of pregnancy, kidney disease, thyroid disease, hypokalemia or hypocalcemia (as conditions), restless legs syndrome, varicose veins,[2] and multiple sclerosis.[3]
Electrolyte disturbance may cause cramping and tetany of muscles, particularly hypokalaemia (a low level of potassium) and hypocalcaemia (a low level of calcium). This disturbance arises as the body loses large amounts of interstitial fluidthrough sweat. This interstitial fluid is composed mostly of water andtable salt (NaCl). The loss of osmotically active particles outsidemuscle cells leads to a disturbance of the osmotic balance and swellingof muscle cells as these contain more osmotically active particles.This causes the calcium pump between the muscle lumen and sarcoplasmic reticulum to short circuit and the calcium ions remain bound to the troponin and the muscle contraction is continued. This may occur when the lactic acid is high in the cells.
[edit] Iatrogenic causesStatins are known to cause myalgiaand cramps among other side effects. Additional factors increasingprobability for these adverse side effects are physical exercise, age,female gender, history of cramps and hypothyroidism. Up to 80% of athletes using statins suffer significant muscular adverse effects including cramps,[4] the rate appears to be approximately 10-25% in typical population using statins.[5][6]In some cases these adverse effects will disappear after switching to adifferent statin, however they should not be ignored if they persist asthey can, in rare cases, develop into a more serious problem. CoenzymeQ10 supplementation can be helpful to avoid some statin related adverseeffects but currently there is not enough evidence to proveeffectiveness in avoiding myopathy or myalgia.[7]
[edit] TreatmentMuscle cramps can be treated by applying a soft massage on thecramped muscle, stretching your hands up above you and breathing indeeply through the mouth, stretching the muscle and applying heat orcold. Heat improves superficial blood circulation and makes musclesmore flexible, so some people find heat to be soothing for musclecramps. Application of excessive heat or cold to sore muscles may bringon cramps. Pounding on a cramped muscle can increase soreness. Tryingto put weight on a cramp too soon can cause another cramp, or even atemporary loss of ability to use that muscle.
- In the case of inadequate oxygenation, excess lactic acid, produced by anaerobic respiration,builds up and stresses the muscle. In addition to the methods describedabove, cramps from poor oxygenation can be improved by rapid deepbreathing.
- Cramps from lack of water and/or salt can be treated by drinking water and/or increasing salt intake, respectively.
There is no scientific evidence to support the widely held claim bythe sports nutrition industry that intake of specially composedelectrolyte drinks has any advantage over intake of plain table salt(via drink or food) and water to counter these electrolyte disturbancesand muscle cramps in people with a well-functioning renal system.
Eating foods high in potassium can help prevent muscle cramps.[8]
In the case of cramps caused by varicose veins, treatment of theaffected veins with sclerotherapy, endovenous laser or surgery usuallyprovides relief.
Quinine has been prescribed for the treatment of leg cramps. However, because of the drug's risks, the United States FDA has declared it should not be used to prevent or treat leg cramps.[9]
[edit] Specific types of cramps
[edit] Smooth muscle crampsSmooth muscle contractions lie at the heart of the cramping (or colicky) pain of internal organs. These include the intestine, uterus, ureter (in kidney stone pain), and various others.
[edit] Menstrual crampsMain article: Dysmenorrhea
Menstruation is also highly likely to cause cramps of varying severity in the abdomen that may radiate to the lower back and thighs. Menstrual cramps can be treated with ibuprofen, acetaminophen (paracetamol),stretching exercises, or the application of heat through such means aswarm baths or heating pads. Menstrual cramps that do not respond toself-treatment can be a symptom of endometriosis or other health problems.
[edit] Skeletal muscle crampsSkeletal muscles are muscles that can be voluntarily controlled. Of the skeletal muscles, those which cramp the most often are the calves, thighs, and arches of the foot. These cramps are seemingly associated with strenuous activity and can be intensely painful.
[edit] Nocturnal leg crampsNocturnal leg cramps are involuntary muscle contractions that occur in the calves, soles of the feet,or other muscles in the body during the night or (less commonly) whileresting. Only a few fibers of a muscle may be activated.[10]The duration of nocturnal leg cramps is highly variable with crampssometimes only lasting a few seconds and other times several minutes.Soreness in the muscles may remain for some time after the cramp ends.These cramps are more common in older people but may happen to anyone.They can happen quite frequently in teenagers and in some people whilethey are exercising at night. Nocturnal leg cramps can be very painful,especially if the person is dehydrated. Usually, putting some pressureon the affected leg by walking some distance will make the cramp goaway.
The precise cause of these cramps is unclear. Potential contributing factors are believed to include dehydration, low levels of certain minerals (magnesium, potassium, calcium, and sodium),and the reduced blood flow through the muscles attendant in prolongedsitting or lying down. Less common causes include more seriousconditions or the use of drugs.
Nocturnal leg cramps may be relieved by stretching the affected legstraight out and pointing the toes upward. People report that quicklystanding up and walking a few steps may also shorten the duration of acramp.
Nocturnal leg cramps (almost exclusively calf cramps) are consideredto be 'normal' during the late stages of pregnancy. They can howevervary in intensity from mild to incredibly painful. Also, the standard R.I.C.E. treatment may be used.
[edit] See also
[edit] References- ^ http://www.medicinenet.com/muscle_cramps/page2.htm#2whatare
- ^ Bergin J. The Vein Book, Hardcover text, Editor Bergin J , 2007.
- ^ Muscle Cramps at WebMD
- ^ SinzingerH, O'Grady J (2004). "Professional athletes suffering from familialhypercholesterolaemia rarely tolerate statin treatment because ofmuscular problems". Br J Clin Pharmacol 57 (4): 525–8. doi:10.1111/j.1365-2125.2003.02044.x. PMID 15025753.
- ^ BruckertE, Hayem G, Dejager S, Yau C, Bégaud B (2005). "Mild to moderatemuscular symptoms with high-dosage statin therapy in hyperlipidemicpatients--the PRIMO study". Cardiovasc Drugs Ther 19 (6): 403–14. doi:10.1007/s10557-005-5686-z. PMID 16453090.
- ^ Dirks, A. J. (2006). "Statin-induced apoptosis and skeletal myopathy". Am. J. Physiol., Cell Physiol. 291 (6): C1208–12. doi:10.1152/ajpcell.00226.2006. PMID 16885396.
- ^ Lamperti C, Naini AB, Lucchini V, et al (2005). "Muscle coenzyme Q10 level in statin-related myopathy". Arch. Neurol. 62 (11): 1709–12. doi:10.1001/archneur.62.11.1709. PMID 16286544.
- ^ Ohio State University Extension: News Chow Line: Potassium-rich foods deter muscle cramps
- ^ United States Food and Drug Administration (2006-12-11). [http://www.fda.gov/bbs/topics/NEWS/2006/NEW01521.html"FDA Orders Unapproved Quinine Drugs from the Market and CautionsConsumers About Off-Label Use Proxy-Connection: keep-aliveCache-Control: max-age=0 Quinine to Treat Leg Cramps"]. http://www.fda.gov/bbs/topics/NEWS/2006/NEW01521.html. Retrieved on 2008-02-15.
- ^ http://www.medicinenet.com/muscle_cramps/article.htm
Muscle Cramp
Who Gets Cramps
Cause
Prevention
Symptoms
Diagnosis
Treatment
Have you ever experienced a "charley horse"? If yes, you probably stillremember the sudden, tight and intense pain caused by a muscle lockedin spasm.
A cramp is an involuntary and forcibly contracted muscle that does notrelax. Cramps can affect any muscle under your voluntary control(skeletal muscle). Muscles that span two joints are most prone tocramping. Cramps can involve part or all of a muscle, or severalmuscles in a group.
The most commonly affected muscle groups are:
- Back of lower leg/calf (gastrocnemius)
- Back of thigh (hamstrings)
- Front of thigh (quadriceps)
Cramps in the feet, hands, arms, abdomen, and along the rib cage are also very common.
Top of page
Who Gets Cramps
Just about everyone will experience a muscle cramp sometime in life. Itcan happen while you play tennis or golf, bowl, swim, or do anyexercise. It can also happen while you sit, walk, or even just sleep.Sometimes the slightest movement that shortens a muscle can trigger acramp.
Some people are predisposed to muscle cramps and get them regularly with any physical exertion.
Those at greatest risk for cramps and other ailments related toexcess heat include infants and young children, people over age 65, andthose who are ill, overweight, overexert during work or exercise, ortake drugs or certain medications.
Muscle cramps are very common among endurance athletes (i.e.,marathon runners and triathletes) and older people who performstrenuous physical activities.
- Athletes are more likely to get cramps in the preseason when the bodyis not conditioned and therefore more subject to fatigue. Cramps oftendevelop near the end of intense or prolonged exercise, or 4-6 hourslater.
- Older people are more susceptible to muscle cramps due to normal muscleloss (atrophy) that begins in the mid-40s and accelerates withinactivity. As you age, your muscles cannot work as hard or as quicklyas they used to. The body also loses some of its sense of thirst andits ability to sense and respond to changes in temperature.
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Cause
Although the exact cause of muscle cramps is unknown (idiopathic), someresearchers believe inadequate stretching and muscle fatigue leads toabnormalities in mechanisms that control muscle contraction. Otherfactors may also be involved, including poor conditioning, exercisingor working in intense heat, dehydration and depletion of salt andminerals (electrolytes).
Stretching and Muscle Fatigue Muscles are bundles of fibers that contract and expand to producemovement. A regular program of stretching lengthens muscle fibers sothey can contract and tighten more vigorously when you exercise. Whenyour body is poorly conditioned, you are more likely to experiencemuscle fatigue, which can alter spinal neural reflex activity.Overexertion depletes a muscle's oxygen supply, leading to build up ofwaste product and spasm. When a cramp begins, the spinal cordstimulates the muscle to keep contracting.
Heat, Dehydration, and Electrolyte Depletion Muscle cramps are more likely when you exercise in hot weather becausesweat drains your body's fluids, salt and minerals (i.e., potassium,magnesium and calcium). Loss of these nutrients may also cause a muscleto spasm.
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Prevention
To avoid future cramps, work toward better overall fitness. Do regularflexibility exercises before and after you work out to stretch musclegroups most prone to cramping.
Warm Up. Always warm up before stretching.
Calf Muscle Stretch. In a standing lunge with both feet pointed forward, straighten the rear leg. (Repeat with opposite leg.)
Hamstring Muscle Stretch. Sit with one leg folded inand the other straight out, foot upright and toes and ankle relaxed.Lean forward slightly, touch foot of straightened leg. (Repeat withopposite leg.)
Quadriceps Muscle Stretch. While standing, hold top of foot with opposite hand and gently pull heel toward buttocks. (Repeat with opposite leg.)
Hold each stretch briefly, then release. Never stretch to the point of pain.
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Symptoms
Muscle cramps range in intensity from a slight tic to agonizing pain. Acramping muscle may feel hard to the touch and/or appear visiblydistorted or twitch beneath the skin. A cramp can last a few seconds to15 minutes or longer. It might recur multiple times before it goesaway.
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Diagnosis
Although most muscle cramps are benign, sometimes they can indicate a serious medical condition.
See your doctor if cramps are severe, happen frequently, respond poorlyto simple treatments, or are not related to obvious causes likestrenuous exercise. You could have problems with circulation, nerves,metabolism, hormones, medications, or nutrition.
Muscle cramps may be a part of many conditions that range from minor tosever, such as Lou Gehrig's disease (amyotrophic lateral sclerosis),spinal nerve irritation or compression (radiculopathy), hardening ofthe arteries, narrowing of the spinal canal (stenosis), thyroiddisease, chronic infections, and cirrhosis of the liver.
Give the doctor your medical history including details about allergies, illnesses, injuries, surgeries, and medications.
How long have you experienced cramps? Is there a family history of theproblem? Do your cramps occur only after exercise, or do they happenwhile at rest? Does stretching relieve the cramps? Do you have muscleweakness or other symptoms? Your doctor may want to take a routineblood test to rule out diseases.
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Treatment
Cramps usually go away on their own without seeing a doctor.
- Stop doing whatever activity triggered the cramp.
- Gently stretch and massage the cramping muscle, holding it in stretched position until the cramp stops.
- Apply heat to tense/tight muscles, or cold to sore/tender muscles.
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