Electromyogram or EMG is defined as a test that records the electrical activity of muscles. Normal muscles produce a typical pattern of electrical current that is usually proportional to the level of muscle activity. Diseases of muscle and/or nerves can produce abnormal electromyogram patterns. Read more: Electromyogram (EMG) Article
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Related Disease Conditions
Muscle spasms are involuntary muscle contractions that come on suddenly and are usually quite painful. Dehydration, doing strenuous exercise in a hot environment, prolonged muscle use, and certain diseases of the nervous system may cause muscle spasms. Symptoms and signs of a muscle spasm include an acute onset of pain and a possible bulge seen or felt beneath the skin where the muscle is located. Gently stretching the muscle usually resolves a muscle spasm.
Low Back Pain (Lumbar Spine Pain)
There are many causes of back pain. Pain in the low back can relate to the bony lumbar spine, discs between the vertebrae, ligaments around the spine and discs, spinal cord and nerves, muscles of the low back, internal organs of the pelvis and abdomen, and the skin covering the lumbar area.
Piriformis syndrome may develop if the piriformis muscle spasms and compresses the sciatic nerve. This causes buttock pain that radiates down the back of the leg along the sciatic nerve. Symptoms include numbness, a pins-and-needles tingling sensation, and low back pain. Treatment of piriformis syndrome depends upon the syndrome's phase: acute, recovery, or maintenance.
Muscle cramps are involuntarily and forcibly contracted muscles that do not relax. Extremely common, any muscles that have voluntary control, including some organs, are subject to cramp. Since there is such variety in the types of muscle cramps that can occur, many causes and preventative medications are known. Stretching is the most common way to stop or prevent most muscle cramps.
Sciatica pain, caused by irritation of the sciatic nerve, typically radiates from the low back to behind the thigh to below the knee. Disc herniation is usually the cause of sciatica. Medication to alleviate pain, physical therapy, and bed rest are treatments for sciatica.
Neck Pain (Cervical Pain)
Neck pain (cervical pain) may be caused by any number of disorders and diseases. Tenderness is another symptom of neck pain. Though treatment for neck pain really depends upon the cause, treatment typically may involve heat/ice application, traction, physical therapy, cortisone injection, topical anesthetic creams, and muscle relaxants.
Peripheral neuropathy is a problem with the functioning of the nerves outside of the spinal cord. Symptoms may include numbness, weakness, burning pain (especially at night), and loss of reflexes. Possible causes may include carpel tunnel syndrome, shingles, vitamin or nutritional deficiencies, and illnesses like diabetes, syphilis, AIDS, and kidney failure. Peripheral neuropathy is diagnosed with exams and tests. Treatment for the condition depends on the cause. Usually, the prognosis for peripheral neuropathy is good if the cause can be successfully treated or prevented.
A pinched nerve causes pain, numbness, or tingling in the affected area due to pressure on a nerve. Carpal tunnel and sciatica are two examples of conditions caused by a pinched nerve. A pinched nerve is diagnosed by taking a patient history and performing a physical examination. Electromyography may be performed. Treatment for a pinched nerve depends on the underlying cause.
Myasthenia gravis, a chronic autoimmune neuromuscular disease. Varying degrees of weakness of the voluntary muscles of the body are the main characteristics. A defect in the transmission of nerve impulses of the muscles is the cause of myasthenia gravis. Myasthenic crisis is when the muscles that control breathing weaken, which requires immediate medical attention. Symptoms include weakness of the eye muscles, facial expression, and difficulty swallowing. Treatment of myasthenia gravis includes medical therapies to control the symptoms of the disease.
Radiculopathy, a condition in which a nerve or nerves along the spine are compressed causing pain, numbness, weakenss, and tingling along the nerve(s). Some causes of radiculopathy include bone spurs, disc hernation, osteoarthritis, tumors, infection, and neuropathy. There are many types of radiculopathy, including cervical radiculopathy, lumbar radiculopathy, and thoracic radiculopathy. Treatment depends on the are of nerve compression. Surgery is generally not required.
Polymyositis and Dermatomyositis
Polymyositis is a disease of the muscle featuring inflammation of the muscle fibers. It results in weakness of the muscles which can be severe and when associated with skin rash, is referred to as dermatomyositis. Although the cause of this disease is unknown, diagnosis includes physical examination of muscle strength, blood tests for muscle enzymes, electrical tests of muscle and nerves, and conformation by a muscle biopsy. Treatment of polymyositis and dermatomyositis includes high doses of cortisone-related medications, immune suppression, and physical therapy.
Swallowing Problems (Dysphagia)
Dysphagia or difficulty in swallowing, swallowing problems. Dysphagia is due to problems in nerve or muscle control. It is common, for example, after a stroke. Dysphagia compromises nutrition and hydration and may lead to aspiration pneumonia and dehydration.
MS (Multiple Sclerosis) vs. ALS (Amyotrophic Lateral Sclerosis) Differences and Similarities
ALS (amyotrophic lateral sclerosis, Lou Gehrig's disease) and MS (multiple sclerosis) are both diseases of the nervous system (neurodegenerative). ALS is a disease in which the nerve cells in the body are attacked by the immune system, although it's not considered an autoimmune disease by some scientists. MS is an autoimmune disease in which the insulated covering of the nerves (myelin sheath) in the CNS (central nervous system) degenerate, or deteriorate. Scientists don't know the exact cause of either problem. However, they have discovered that mutations in the gene that produces the SOD1 enzyme were associated with some cases of familial ALS. Scientists also theorize that multiple sclerosis may be caused by infection or vitamin D deficiency. ALS occurs between 50-70 years of age (the average age of occurrence ALS is 55), and mostly affects men. While MS occurs between 20-60 years of age, and mostly affects women. About 30,000 people in the US have ALS, and an average of 5,000 new diagnoses per year (that's about 15 new cases per week). Worldwide, MS affects more than 2.3 million people, with about 10,000 new cases diagnosed each year (that's about 200 new diagnoses per week).Some of the signs and symptoms of both diseases include muscle weakness, muscle spasms, problems walking, fatigue, slurred speech, and problems swallowing. ALS signs and symptoms that are different from MS include problems holding the head upright, clumsiness, muscle cramps and twitches, problems holding objects, and uncontrollable periods of laughing or crying. MS signs and symptoms that are different from ALS include vision problems, vertigo and balance problems, sexual problems, memory problems, depression, mood swings, and digestive problems. There is no cure for either disease, however the prognosis and life expectancy are different. Multiple sclerosis is not a fatal condition, while ALS progresses rapidly and leads to death.
A herniated disc may be caused by injury or degeneration from age. Symptoms depend on the location of the herniation and whether nerve tissue is being irritated. An MRI or CT scan is performed to diagnose a herniated disc. Treatment may involve physical therapy, cortisone injection, pain medications, anti-inflammatory medications, muscle relaxants, and surgery.
There are many types of urinary incontinence (UI), which is the accidental leakage of urine. These types include stress incontinence, urge incontinence, and overflow incontinence. Urinary incontinence in men may be caused by prostate or nerve problems. Treatment depends upon the type and severity of the UI and the patient's lifestyle.
Cauda Equina Syndrome
Cauda equina syndrome is a medical emergency condition that is caused by the uncommon compression of the nerves at the end of the spinal cord. Symptoms of cauda equina syndrome include lower back pain, tingling and/or numbness in the buttocks and lower extremities, bowel or bladder incontinence, and weakness in the legs. Causes of cauda equina syndrome include herniated discs, hematomas, or infection. Treatment is generally prompt surgery.
Sleep apnea is defined as a reduction or cessation of breathing during sleep. The three types of sleep apnea are central apnea, obstructive apnea (OSA), and a mixture of central and obstructive apnea. Central sleep apnea is caused by a failure of the brain to activate the muscles of breathing during sleep. OSA is caused by the collapse of the airway during sleep. OSA is diagnosed and evaluated through patient history, physical examination and polysomnography. There are many complications related to obstructive sleep apnea. Treatments are surgical and non-surgical.
Degenerative Disc Disease and Sciatica
Degenerative disc disease makes the disc more susceptible to herniation (rupture) which can lead to localized or radiating pain. The pain from degenerative disc or joint disease of the spine is usually treated conservatively with intermittent heat, rest, rehabilitative exercises and medications to relieve pain, muscle spasm and inflammation.
Thoracic Outlet Syndrome (TOS)
Thoracic outlet syndrome is a condition where symptoms are produced from compression of nerves or blood vessels because the passageway through the neck and armpit is inadequate. Symptoms of thoracic outlet syndrome include neck, shoulder, and arm pain, and numbness or impaired circulation to the extremities.
Botulism is an illness caused by a neurotoxin produced by the bacterium Clostridium botulinum. There are three types of botulism: food-borne, wound, and infant. Symptoms include muscle paralysis, dry mouth, constipation, slurred speech, and blurred vision. If food-borne and wound botulism are detected early enough, they may be treated with an antitoxin.
Carpal Tunnel Syndrome
Carpal tunnel syndrome is a condition in which irritation of the wrist's median nerve causes tingling and numbness of the thumb, index, and the middle fingers. Treatment of carpal tunnel syndrome depends on the severity of the symptoms and the nature of any disease that might be causing the symptoms.
Dystonia disorders cause involuntary movements and prolonged muscle contraction, resulting in twisting body motions, tremor, and abnormal posture. There are many forms of dystonia. Some types of dystonia respond to dopamine, or can be controlled with dedative-type medications, or surgery.
ALS (Amyotrophic Lateral Sclerosis) Symptoms, Causes, Life Expectancy
Amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease) is a neurological disease that progresses rapidly. The disease attacks the nerve cells responsible for the control of voluntary muscles. Early symptoms include cramping, twitching, or stiffness of the muscles; slurred nasal speech; difficulty swallowing or chewing, and muscle weakness in an arm or leg. Currently, the cause of ALS is not known. ALS is a fatal disease. No cure has been found for ALS, however, the drug riluzole (Rilutek) is FDA approved, and this drug reduces the damage to motor neurons by decreasing the release of glutamate.
Lumbar Spinal Stenosis
Lumbar stenosis can be caused by degenerative arthritis (the most common cause), tumor, infection, or metabolic disorders (Paget's disease of the bone). Symptoms include low back pain, weakness, pain, numbness, and loss of sensation in the legs. Other conditions may cause similar symptoms of lumbar stenosis, including diabetic neuropathy, claudication, and peripheral vascular disease. Lumbar stenosis may be treated with medication or surgery.
Charcot-Marie-Tooth Disease (CMT)
Charcot-Marie-Tooth disease is one of the most common inherited neurological disorders. Charcot-Marie-Tooth disease affects the peripheral nerves. CMT symptoms and signs include weakness of the lower leg muscles and foot, foot drop, foot deformities, etc. There are several forms of Charcot-Marie-Tooth disease. Inherited gene mutations are the cause of Charcot-Marie-Tooth disease. There is no cure for Charcot-Marie-Tooth disease, however, therapeutic measures and mild exercise may help symptoms.
Friedreich's Ataxia Syndrome
Friedreich's ataxia syndrome is a rare inherited (genetic) disease that causes progressive nervous system damage and movement problems. Friedreich's ataxia syndrome usually begins in childhood and leads to impaired muscle coordination (ataxia) that worsens over time. Symptoms of Friedreich's ataxia syndrome include poor balance, slurred and jerky speech, and difficulty with coordination. Genetic testing and other procedures are used to confirm the diagnosis of Friedreich's ataxia syndrome. There is no effective treatment or cure for Friedreich's ataxia syndrome, however; the symptoms of Friedreich's ataxia syndrome can be treated.
Post-polio syndrome (PPS) is a group of signs and symptoms that show up two to four decades after the initial polio infection. Symptoms of PPS include fatigue, pain, sleep disorders, muscle twitching, gastrointestinal problems, and weakness. Treatment focuses on slowing down to conserve energy and relieving symptoms with pain relievers.
Nerve Disease and Bladder Control
A nerve problem might affect your bladder control if the nerves that are supposed to carry messages between the brain and the bladder do not work properly. Such problems include urine retention, poor control of sphincter muscles, and overactive bladder. Treatment depends upon the cause of the nerve damage and resulting type of bladder control problem.
Variant Creutzfeldt-Jakob Disease (vCJD)
Variant Creutzfeldt-Jakob disease (vCJD) is a degenerative, fatal brain disorder in humans. Symptoms are initially psychiatric or sensory and include neurological abnormalities such as ataxia, dementia, and myoclonus. There is no known treatment for vCJD.
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