A muscle that involuntarily contracts is called a spasm. If the spasm is forceful and sustained, it becomes a cramp. A muscle cramp is thus defined as an involuntarily and forcibly contracted muscle that does not relax. This causes a visible or palpable hardening of the involved muscle. A muscle cramp, technically, occurs when muscle tightens and shortens causing a sudden severe pain. Muscle cramps can last anywhere from a few seconds to a quarter of an hour or occasionally longer. They can recur frequently.

 

A muscle that involuntarily contracts is called a spasm. If the spasm is forceful and sustained, it becomes a cramp. A muscle cramp is thus defined as an involuntarily and forcibly contracted muscle that does not relax. This causes a visible or palpable hardening of the involved muscle. A muscle cramp, technically, occurs when muscle tightens and shortens causing a sudden severe pain. Muscle cramps can last anywhere from a few seconds to a quarter of an hour or occasionally longer. They can recur frequently. The cramp may involve a part of a muscle, the entire muscle, or a group of muscles. Cramps are extremely common. Cramps are very unpleasant, often painful and lead to a feeling of discomfort.

Causes of Muscle Cramps

• Exertion
• Exercise
• Exercise
• Electrolyte imbalance
• Excessive perspiration
• Loss of salt
• Viral Infection
• Bacterial infection
• Muscle injury
• Muscle metabolism disorders
• Dermatomyositis - cause multiple muscle cramps
• Polymyositis - cramps in many muscles
• Polymyalgia rheumatica
• Diabetes - may cause muscle cramps if undiagnosed or poorly controlled
• Diabetic ketoacidosis - muscle breakdown may cause muscle cramps
• Rheumatoid arthritis
• Thyroid disease
• Circulatory disorders
• Intermittent claudication - usually causing calf muscle pain
• Tetanus
• Unaccustomed exercise
• Cauda equine ischemia
• McArdle's disease
• Lipid storage myopathy
• Myophosphorylase deficiency
• Phosphofructokinase deficiency
• Hypocalcaemia

Medicines Resulting in Muscular Cramps

• Salbutamol and terbutaline
• Raloxifene
• Opiate withdrawal
• Diuretics cause electrolyte loss
• Nifedipine
• Phenothiazines
• Penicillamine
• Nicotinic acid

Symptoms and Signs

• Sudden and sharp muscle pain which may be spasm, contraction most commonly affecting lower limbs
• A hard lump of muscle tissue that can be easily felt and it may be visible beneath skin

Diagnostic Investigations

Following investigations can be performed depending on case to case basis

• Liver function tests
• Thyroid function tests
• Serum calcium or magnesium
• Creatine kinase if a myopathy is suspected
• Lead levels if plumbism is suspected

Preventive Measures

• Drink plenty of water with glucose or juices
• Eat plenty of vegetables, nuts and dry fruits 
• Take a break when you happen to walk/ work / travel continuously
• Rest with legs elevated if there is any swelling or edema 
• Treatment for vascular disorders or varicose veins, if any
• Prefer walk before going to bed
• Shake the part involved to get quick circulation
• Warm up of muscles must be done before straining them
• Stretching or massaging of the muscles involved 
• Regular exercising
• Legs must be kept warm by covering it with blanket while sleeping  
• One should avoid unnecessary medications
• Avoid standing in water or walking or swimming for a prolonged time
• Avoid wearing tight under garments and tight-fitting socks and shoes
• Avoid Smoking, drinking and illicit drugs

 

Treatment and Drugs

Mainstay of the treatment is on stretching unless there is some underlying cause. If a underlying cause is detected then a cause specific treatment can be started which will subside the cause in the due course of treatment.