Sciatica

Also from Answers.com... Common Sleeping Problems Find out how you can get a good night's sleep.

More about Sciatica: Causes and symptoms Diagnosis Treatment Alternative treatment Prognosis Prevention Resources

Definition

Sciatica refers to pain or discomfort associated with the sciatic nerve. This nerve runs from the lower part of the spinal cord, down the back of the leg, to the foot. Injury to or pressure on the sciatic nerve can cause the characteristic pain of sciatica: a sharp or burning pain that radiates from the lower back or hip, possibly following the path of the sciatic nerve to the foot.

Description

The sciatic nerve is the largest and longest nerve in the body. About the thickness of a person's thumb, it spans from the lower back to the foot. The nerve originates in the lower part of the spinal cord, the so-called lumbar region. As it branches off from the spinal cord, it passes between the bony vertebrae (the component bones of the spine) and runs through the pelvic girdle, or hip bones. The nerve passes through the hip joint and continues down the back of the leg to the foot.

Sciatica is a fairly common disorder and approximately 40% of the population experiences it at some point in their lives. However, only about 1% have coexisting sensory or motor deficits. Sciatic pain has several root causes and treatment may hinge upon the underlying problem.

Of the identifiable causes of sciatic pain, lumbosacral radiculopathy and back strain are the most frequently suspected. The term lumbosacral refers to the lower part of the spine, and radiculopathy describes a problem with the spinal nerve roots that pass between the vertebrae and give rise to the sciatic nerve. This area between the vertebrae is cushioned with a disk of shock-absorbing tissue. If this disk shifts or is damaged through injury or disease, the spinal nerve root may be compressed by the shifted tissue or the vertebrae.

This compression of the nerve roots sends a pain signal to the brain. Although the actual injury is to the nerve roots, the pain may be perceived as coming from anywhere along the sciatic nerve.

The sciatic nerve can be compressed in other ways. Back strain may cause muscle spasms in the lower back, placing pressure on the sciatic nerve. In rare cases, infection, cancer, bone inflammation, or other diseases may be causing the pressure. More likely, but often overlooked, is the piriformis syndrome. As the sciatic nerve passes through the hip joint, it shares the space with several muscles. One of these muscles, the piriformis muscle, is closely associated with the sciatic nerve. In some people, the nerve actually runs through the muscle. If this muscle is injured or has a spasm, it places pressure on the sciatic nerve, in effect, compressing it.

In many sciatica cases, the specific cause is never identified. About half of affected individuals recover from an episode within a month. Some cases can linger a few weeks longer and may require aggressive treatment. In some cases, the pain may return or potentially become chronic.

— Julia Barrett

Dictionary: sci·at·i·ca  (sī-ăt'ĭ-kə)

Pain along the sciatic nerve usually caused by a herniated disk of the lumbar region of the spine and radiating to the buttocks and to the back of the thigh.

[Middle English, from Medieval Latin, from feminine of sciaticus, of the hip. See sciatic.]

Definition

Sciatica is pain in the lower back that can radiate down the buttocks and leg and occasionally into the foot. The pain is a result of inflammation of the sciatic nerve, usually from a herniated vertebral disk, although other causes are common. Sciatica is one of the frequently reported causes of lower back pain.

Description

Sciatica, also known as lumbago or lumbar radiculopathy, causes pain as a result of pressure on the sciatic nerve. The sciatic nerve is formed from lumbar roots that emerge from the spinal column. It rises into the pelvis, and travels down the buttocks, the leg, and into the foot. Occurring on both the left and right side of the body, these nerves are the largest in the body, with a diameter as great as a finger; they branch at several points along their path. Sciatica occurs when these nerves become irritated, most often because of a herniated vertebral disk that puts pressure on the sciatic nerve as it emerges from the spinal column.

Sciatica causes pain that may be constant or intermittent and it may include numbness, burning, or tingling. Coughing, sneezing, bending over, or lifting heavy objects may increase the pain. In some cases, there is weakening of muscles in the buttocks, legs, and/or feet.

Demographics

Sciatica is one of the most common forms of back pain. It occurs in about 5% of people who visit their doctor for back pain and in 1–3% of the general adult population. It is most common in people who are between 30 and 50 years of age, as those are the ages most prone to herniating vertebral disks. After age 30, the tough exterior of the vertebral disks undergoes a natural thinning, making it easier for the gel-like inner core to rupture it. After the age of 50, the interior of the vertebral disk becomes slightly hardened, making it less likely to protrude out.

Causes and symptoms

Pressure on the sciatic nerve can result from poor posture, muscle strain, pregnancy, wearing high heels, or being overweight. A herniated disk in the lumbar spine is the most common cause of sciatica. Herniated disks occur when the gel-like inner core of a vertebral disk (nucleus puposus) ruptures through the tougher outer section (annulus) of the disk. This extrusion puts pressure on the nerve root, causing it to function improperly. Another common cause of sciatica is lumbar spinal stenosis, or narrowing of the spinal canal, which puts pressure on the roots making up the sciatic nerve. Degenerative disk disease causes sciatica when the disk weakens enough to allow excessive movement of the vertebrae near the sciatic nerve. In addition, the degenerated disk may leak irritating proteins in the vicinity of the nerve. Although isthmic spondylolisthesis is relatively common in adults, it only occasionally causes sciatica. This occurs when a vertebra develops a stress fracture and slips, slightly impinging on the sciatic nerve as it exits the spine. Piriformis syndrome causes sciatica when the sciatic muscle is irritated as it runs under the piriformis muscle in the buttocks. Finally, sacroiliac joint dysfunction can put pressure on the sciatic nerve, leading to sciatica.

Diagnosis

A physician will perform a physical exam on a patient complaining of sciatica in order to try to identify the part of the nerve that is irritated. This exam may include squatting, walking, standing on toes, and leg raising tests. Most commonly, lifting the leg to a 45° angle while holding it straight helps localize the pain. Other tests that may be performed include x ray to look for stress fractures in bones and magnetic resonance imaging (MRI) or computerized tomography (CT) to look at softer tissues and ligaments. A nerve conduction velocity test and electromyography may also aid in diagnosis.

Treatment

In most cases, conservative treatments are effective for sciatica. A short period of rest, coupled with the application of cold packs and heat packs to the affected area, reduces inflammation of the nerve. Non-steroidal anti-inflammatory medicines can also be taken to decrease inflammation. Injection of corticosteriods may also be recommended to decrease swelling of the nerve. Physical therapy and short walks are also recommended.

If after three or more months, sciatica continues and become progressively worse, surgical techniques can be used to relieve the pressure on the sciatic nerve. Surgery is often very effective in relieving pain, although results can vary depending upon the cause of the sciatica. Overall, about 90% of patients undergoing surgery for sciatica pain receive some relief.

Recovery and rehabilitation

Usually, sciatica improves within a few weeks. In cases of severe injury to the nerve, such as laceration or other trauma, recovery may be not possible or may be limited. The extent of disability may vary from partial to complete loss of movement or sensation in the affected leg. Nerve pain may also persist.

Clinical trials

A recent drug trial found that the drug Remicade (infliximab), which is used to treat arthritis, is often effective for treating sciatica. The drug reduces the level of a chemical called tumor necrosis factor alpha, which plays an important role in the inflammatory response of the body. It is thought that this factor is also critical to sciatica.

The National Institutes of Health (NIH) are conducting three ongoing studies on the treatment of sciatica. One study investigates the effects of the antidepressants desipramine and benztropine on sciatica. A second looks at the effects of magnets on sciatica. A third investigates the role of two drugs, nortriptyline and MS Contin (a type of morphine), as treatment for sciatica. Contact information for these studies is the National Institute for Dental and Craniofacial Research (NIDCR), 9000 Rockville Pike, Bethesda, MD 20892; the toll-free number is (800) 411-1222.

Resources

BOOKS

Credit, Larry P., Sharon G. Hartunian, and Margaret J. Nowak. Relieving Sciatica. Vonore, TN: Avery Publishing Group, 2000.

Fishman, Loren, and Carol Ardman. Back Pain: How to Relieve Low Back Pain and Sciatica. New York: W.W. Norton and Company, 1997.

OTHER

Hochschuler, Stephen H. "What You Need to Know about Sciatica." SpineHealth.com. February 12, 2004 (April 4, 2004). http://www.spine-health.com/topics/cd/d_sciatica/sc01.html.

"Sciatica." American Association of Orthopaedic Surgeons. February 12, 2004 (April 4, 2004). http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=167&topcategory=Spine.

"Sciatica." Harvard Medical Schools Consumer Health Information. February 12, 2004 (April 4, 2004). http://www.intelihealth.com/IH/ihtIH/WSIHW000/9339/25686.html.

ORGANIZATIONS

American Academy of Orthopaedic Surgeons. 6300 North River Road, Rosemont, IL 60018-4262. (847) 823-7186 or (800) 346-AAOS; Fax: (847) 823-8125. http://www.aaos.org.

National Institute of Arthritis and Musculoskeletal and Skin Diseases. Office of Communications and Public Liaison, National Institute of Health, Bldg. 31, Room 4C02 31 Center Dr. MSC 2350. Bethesda, MD 20892-2350. (301) 496-8190; Fax: (301) 480-2814. http://www.niams.nih.gov/.

Juli M. Berwald, PhD

Pain in the lower extremities, hips, and back caused by irritation of the sciatic nerves. The location of the specific pain and the causes producing it are quite varied.

Sciatica may result from mechanical pressure on the nerves or their roots in the cord. Trauma, herniated intervertebral disks, pregnancy, inflammation, or tumors may cause compression. Toxic or metabolic disorders, such as lead poisoning, diabetes mellitus, alcoholism, and vitamin-B deficiency may induce sciatic pain by producing changes in the nerves. Inflammations, both local and systemic, may also cause temporary or permanent nerve injury. Certain viral diseases, syphilis, and local infections act in this manner. See also Syphilis; Virus; Vitamin.

In addition, lesions in the anal region and the prostate may induce sciatica through reflex stimulation. Joint diseases, pelvic strain, and injury most often precipitate an attack. The pain of sciatica may begin suddenly and violently or gradually, as a nagging discomfort. The pain is usually along the leg, with later extension to the thigh and back. Numbness of the outside of the foot may occur. See also Pain.

A severe pain radiating down the lower back into the leg. It is caused by inflammation or irritation of the sciatic nerve, the longest and largest nerve in the body. The sciatic nerve supplies the hamstring muscles and runs from the spinal cord to the knee where it divides into two smaller nerves. Onset of sciatica may be sudden; it is often brought on by strain of the lower back or a slipped disc (see prolapsed intervertebral disc).

Definition

Sciatica refers to pain or discomfort associated with the sciatic nerve. This nerve runs from the lower part of the spinal cord down the back and side of the leg to the foot. Injury to or pressure on the sciatic nerve can cause the characteristic pain of sciatica: a sharp or burning pain or even numbness that radiates from the lower back or hip, possibly following the path of the sciatic nerve to the foot.

Description

The sciatic nerve is the largest and longest nerve in the body. About the thickness of a person's thumb, it spans from the lower back to the foot. The nerve originates in the lower part of the spinal cord, the so-called lumbar region. As the sciatic nerve branches off from the spinal cord, it passes between the bony vertebrae (the component bones of the spine) and runs through the pelvic girdle, or hip bones, and the buttock area. The nerve passes through the hip joint and continues down the back and side of the leg to the foot.

Sciatica is a fairly common disorder, approximately 40% of the population experiences it at some point in their lives. However, only about 1% have coexisting sensory or motor deficits. Sciatic pain has several root causes and treatment may hinge upon the underlying problem.

Of the identifiable causes of sciatic pain, lumbosacral radiculopathy and back strain are the most frequently suspected. The term lumbosacral refers to the lower part of the spine, and radiculopathy describes a problem with the spinal nerve roots that pass between the vertebrae and give rise to the sciatic nerve. This area between the vertebrae is cushioned with a disk of shock-absorbing tissue. If this disk shifts or is damaged through injury or disease, the spinal nerve root may be compressed by the shifted tissue or the vertebrae.

This compression of the nerve roots sends a pain signal to the brain. Although the actual injury is to the nerve roots, the pain may be perceived as coming from any point along the sciatic nerve.

The sciatic nerve can be compressed in other ways. Back strain may cause muscle spasms in the lower back, placing pressure on the sciatic nerve. In rare cases, infection, cancer, bone inflammation, or other diseases may cause the pressure. More likely, but often overlooked, is the piriformis syndrome. As the sciatic nerve passes through the hip joint, it shares the space with several muscles. One of these muscles, the piriformis muscle, is closely associated with the sciatic nerve. In some people, the nerve actually runs through the muscle. If this muscle is injured or has a spasm, it places pressure on the sciatic nerve—in effect, compressing it.

In many sciatica cases, the specific cause is never identified. About half of affected individuals recover from an episode within a month. Some cases can linger a few weeks longer and may require aggressive treatment. In other cases, the pain may return or potentially become chronic.

Causes & Symptoms

Persons with sciatica may experience some lower back pain, but the most common symptom is pain that radiates through one buttock and down the back of the adjoining leg. The most identified cause of the pain is compression or pressure on the sciatic nerve. The extent of the pain varies among individuals. Some people describe pain that centers in the area of the hip, and others perceive discomfort all the way to the foot. The quality of the pain also varies; it may be described as tingling, burning, prickly, aching, or stabbing.

Onset of sciatica can be sudden, but it can also develop gradually. The pain may be intermittent or continuous. Certain activities, such as bending, coughing, sneezing, or sitting, may make the pain worse.

Chronic pain may arise from more than just compression on the nerve. According to some pain researchers, physical damage to a nerve is only half of the equation. A recent theory proposes that some nerve injuries result in a release of neurotransmitters and immune system chemicals that enhance and sustain a pain message. Even after the injury has healed or the damage has been repaired, the pain continues. Control of this abnormal type of pain is difficult.

Diagnosis

Before treating sciatic pain, as much information as possible must be collected. The individual is asked to recount the location and nature of the pain, how long it has continued, and any accidents or unusual activities prior to its onset. This information provides clues that may point to back strain or injury to a specific location. Back pain from disk disease, piriformis syndrome, and back strain must be differentiated from more serious conditions such as cancer or infection. Lumbar stenosis, an overgrowth of the covering layers of the vertebrae that narrows the spinal canal, must also be considered. The possibility that a difference in leg lengths is causing the pain should be evaluated; the problem can be easily be treated with a foot orthotic or built-up shoe.

Often, a straight-leg-raising test is done, in which the person lies face upward and the healthcare provider raises the affected leg to various heights. This test pinpoints the location of the pain and may reveal whether it is caused by a disk problem. Other tests, such as having the individual rotate the hip joint, assess the condition of the hip muscles. Any pain caused by these movements may provide information about involvement of the piriformis muscle, and piriformis weakness is tested with additional leg-strength maneuvers.

Further tests may be done depending on the results of the physical examination and initial pain treatment. Such tests might include magnetic resonance imaging (MRI) and computed tomography (CT) scans. Other tests examine the conduction of electricity through nerve tissues, and include studies of the electrical activity generated as muscles contract (electromyography), nerve conduction velocity, and evoked potential testing. A more invasive test involves injecting a contrast substance into the space between the vertebrae and making x-ray images of the spinal cord (myelography), but this procedure is usually done only if surgery is being considered as an option. All of these tests can reveal problems with the vertebrae, the disk, or the nerve itself.

Treatment

Massage is a recommended form of therapy, especially if the sciatic pain arises from muscle spasm. Symptoms may also be relieved by icing the painful area as soon as the pain occurs. Ice should be left on the area for 30–60 minutes several times a day. After two or three days, a hot water bottle or heating pad can replace the ice. Chiropractic or osteopathy may offer possible solutions for relieving pressure on the sciatic nerve and alleviating the accompanying pain. Biofeedback may also be useful as a pain control method. Bodywork, such as the Alexander technique, can assist an individual in improving posture and preventing further episodes of sciatic pain.

Acupuncture is another alternative approach that appears to offer relief to many persons with sciatica, as indicated by several clinical trials in the United States and Europe. The World Health Organization (WHO) lists sciatica as one of 40 conditions for which acupuncture is recognized as an appropriate complementary treatment.

Practitioners of Ayurvedic medicine regard sciatica as a disorder resulting from an imbalance in vata, one of three doshas or energies in the human body. The traditional Ayurvedic treatment for vata disorders is vasti, or administration of an oil-based enema to cleanse the colon. An Ayurvedic herbal preparation that is used to treat sciatica is made from the leaves of Nyctanthes arbor tristis, which is also known as Parijat or "sad tree." A recent study of an alcohol-based extract of this plant indicates that it is effective as a tranquilizer and local anesthetic, which supports its traditional Ayurvedic use.

Western herbalists typically treat sciatica with valerian root to relax the muscle spasms that often accompany sciatica, and with white willow bark for pain relief.

Homeopathic remedies for sciatica include Ruta graveolens, Colocynth (for sciatic pain that is worse in cold or damp weather), or Magnesium phosphoric (for lightning-like pains that are soothed by heat and made worse by coughing).

Allopathic Treatment

Initial treatment for sciatica focuses on pain relief. For acute or very painful flare-ups, bed rest is advised for up to a week in conjunction with medication for the pain. Pain medication includes acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, or muscle relaxants. If the pain is unremitting, opioids may be prescribed for short-term use, or a local anesthetic will be injected directly into the lower back. Massage and heat application may be suggested as adjuncts.

If the pain is chronic, different pain relief medications are used to avoid long-term dosing of NSAIDs, muscle relaxants, and opioids. Antidepressant drugs, which have been shown to be effective in treating pain, may be prescribed alongside short-term use of muscle relaxants or NSAIDs. Local anesthetic injections or epidural steroids are used in selected cases.

As the pain allows, physical therapy is introduced into the treatment regime. Stretching exercises that focus on the lower back, buttock, and hamstring muscles are suggested. The exercises also include finding comfortable, pain-reducing positions. Corsets and braces may be useful in some cases, but evidence for their general effectiveness is lacking. However, they may be helpful to prevent exacerbations related to certain activities.

With less pain and the success of early therapy, the individual is encouraged to follow a long-term program to maintain a healthy back and prevent re-injury. A physical therapist may suggest exercises and regular activity, such as water exercise or walking. Patients are instructed in proper body mechanics to minimize symptoms during light lifting or other activities.

If the pain is chronic and conservative treatment fails, surgery to repair a herniated disk or to cut out part or all of the piriformis muscle may be suggested, particularly if there is evidence of nerve or nerve-root damage.

A new minimally invasive surgical treatment for sciatica was introduced in 2002. It is known as microscopically assisted percutaneous nucleotomy, or MAPN. MAPN allows the surgeon to repair a herniated disk with less damage to surrounding tissues; it shortens the patient's recovery time and relieves the pain of sciatica as effectively as more invasive surgical procedures.

Expected Results

Most cases of sciatica are treatable with pain medication and physical therapy. After four to six weeks of treatment, an individual should be able to resume normal activities.

Prevention

Some sources of sciatica are not preventable, such as disk degeneration, back strain due to pregnancy, or accidental falls. Other sources of back strain, such as poor posture, overexertion, being overweight, or wearing high heels, can be corrected or avoided. Cigarette smoking may also predispose people to pain, and should be discontinued with the onset of pain.

General suggestions for avoiding sciatica or preventing a repeat episode include sleeping on a firm mattress; using chairs with firm back support; and sitting with both feet flat on the floor. Habitually crossing the legs while sitting can place excess pressure on the sciatic nerve. Sitting for long periods of time can also place pressure on the sciatic nerves, so it is recommended to take short breaks and move around during the work day, during long trips, or in other situations that require sitting for extended periods of time. If lifting is required, the back should be kept straight and the legs should provide the lift. Regular exercise, such as swimming and walking, can strengthen back muscles and improve posture. Exercise can also help maintain a healthy weight and lessen the likelihood of back strain.

Resources

Books

Maigne, Robert. "Sciatica." In Diagnosis and Treatment of Pain of Vertebral Origin: A Manual Medicine Approach. Baltimore: Williams & Wilkins, 1996.

Pelletier, Kenneth R., MD. The Best Alternative Medicine, Part II, "CAM Therapies for Specific Conditions: Sciatica." New York: Simon & Schuster, 2002.

Rydevik, Björn, Mitsuo Hasue, and Peter Wehling. Etiology of Sciatic Pain and Mechanisms of Nerve Root Compression, vol. 1: The Lumbar Spine, 2d ed., edited by Sam W. Wiesel, et al. Philadelphia: W.B. Saunders Company, 1996.

Periodicals

Chiodo, A., and A. J. Haig. "Lumbosacral Radiculopathies: Conservative Approaches to Management." Physical Medicine and Rehabilitation Clinics of North America 13 (August 2002): 609-621.

Douglas, Sara. "Sciatic Pain and Piriformis Syndrome." The Nurse Practitioner 22 (May 1997): 166.

Greiner-Perth, R., H. Bohm, and H. El Saghir. "Microscopically Assisted Percutaneous Nucleotomy, An Alternative Minimally Invasive Procedure for the Operative Treatment of Lumbar Disc Herniation: Preliminary Results." Neurosurgical Review 25 (August 2002): 225-227.

Parziale, John R., Thomas H. Hudgins, and Loren M. Fishman. "The Piriformis Syndrome." The American Journal of Orthopedics (December 1996): 819.

Saxena, R. S., B. Gupta, and S. Lata. "Tranquilizing, Antihistaminic and Purgative Activity of Nyctanthes arbor tristis Leaf Extract." Journal of Ethnopharmacology 81 (August 2002): 321-325.

Wheeler, Anthony H. "Diagnosis and Management of Low Back Pain and Sciatica." American Family Physician (October 1995): 1333.

Organizations

American Academy of Medical Acupuncture (AAMA). 4929 Wilshire Blvd., Suite 428, Los Angeles, CA 90010. (323) 937-5514. .

American Academy of Orthopaedic Surgeons (AAOS). 6300 North River Road, Rosemont, IL 60018. (847) 823-7186 or (800) 346-AAOS. .

American Physical Therapy Association (APTA). 1111 North Fairfax Street, Alexandria, VA 22314. (703) 684-APTA or (800) 999-2782. .

National Center for Homeopathy. 801 North Fairfax Street, Alexandria, VA 22314. (703) 548-7790. .

National Institute of Ayurvedic Medicine. 584 Milltown Road, Brewster, NY 10509. (845) 278-8700. .

[Article by: Kathleen Wright; Rebecca J. Frey, PhD]

For more information on sciatica, visit Britannica.com.

Irritation or inflammation of the sciatic nerve characterized by a severe pain radiating down the nerve, from the lower back into the leg. True sciatica causes symptoms below the knee and into the foot. The onset of sciatica may be sudden, and brought on by a strain to the lower back or a slipped disc (see prolapsed intervertebral disc), although sometimes no cause can be identified.

Chronic pain in the hip and upper leg caused by irritation of a large nerve — the sciatic nerve — that runs through the pelvis and down the back of the thigh.

Sciatica
Classification & external resources

Left gluteal region, showing surface markings for arteries and sciatic nerve.
ICD-10	M54.3-M54.4
ICD-9	724.3
eMedicine	emerg/303
MeSH	D012585

Sciatica is pain caused by general compression and/or irritation of one of five nerve roots that are branches of the sciatic nerve. The pain is felt in the lower back, buttock, and/or various parts of the leg and foot. In addition to pain, which is sometimes severe, there may be numbness, muscular weakness, and difficulty in moving or controlling the leg. Typically, the symptoms are only felt on one side of the body.

Although sciatica is a relatively common form of low back pain and leg pain, the true meaning of the term often is misunderstood. Sciatica is a set of symptoms rather than a diagnosis for what is irritating the root of the nerve, causing the pain. This point is important, because treatment for sciatica or sciatic symptoms often will be different, depending upon the underlying cause of the symptoms.

The first cited use of the word "sciatica" was registered in 1450.^[1]

Causes of sciatica

Sciatica is generally caused by the compression of a lumbar spine nerve root L4 or L5 or sacral nerve roots S1, S2 or S3, or far less commonly, by compression of the sciatic nerve itself. When sciatica is caused by compression of a lumbar nerve root it is considered a lumbar radiculopathy (or radiculitis when accompanied with an inflammatory response) from a spinal disc herniation (a herniated intervertebral disc in the spine), or from roughening, enlarging, and/or misaligning of the vertebrae (spondylolisthesis), or degenerated discs.^[2]

"Pseudo-sciatica", which causes symptoms similar to spinal nerve root compression, is caused by the compression of peripheral sections of the nerve, usually from soft tissue tension in the piriformis or related muscles (see piriformis syndrome and see below).

Spinal disc herniation

Main article: Spinal disc herniation

One cause of sciatica is a spinal disc herniation, pressing on one of the sciatic nerve roots. The spinal discs are composed of a spongiform cartilage with a liquid center. The discs separate the vertebrae, thereby allowing room for the nerve roots to properly exit through the spaces between the L4, L5, and sacral vertebrae. The discs cushion the spine from compressive forces, but are weak to pressure applied during rotational movements. That is why a person who bends to one side, at a bad angle, to pick up a piece of paper may more likely herniate a spinal disc than a person falling from a ladder and landing on his or her back. Herniation of a disc occurs when the liquid center of the disc bulges outwards, tearing the external ring of fibers, and compresses a nerve root against the lamina or pedicle of a vertebra, thus causing sciatica.

Spinal stenosis

Main article: Spinal stenosis

Other compressive spinal causes include Spinal Canal Stenosis, a condition wherein the spinal canal (the spaces through which the spinal cord runs) narrows and compresses the spinal cord. This narrowing can be caused by bone spurs, vertebral dislocation, inflammation, or herniated disc which decreases available space for the spinal cord, thus pinching nerves in the spinal cord that travel to the sciatic nerve and irritating them with friction.

Piriformis syndrome

Main article: Piriformis syndrome

The sciatic nerve runs through the piriformis muscle in the buttocks region beneath the gluteal muscles. When the muscle shortens or spasms due to trauma, it can compress or strangle the sciatic nerve beneath the muscle. This cause of sciatic symptoms is piriformis syndrome. This may be the major cause of sciatica when the nerve root is normal.^[3]

The risk of self-inflicted sciatica has increased in recent years with the fashion trend of lower-hanging trousers as well as lower-positioning of the pockets. For instance, sitting on a wallet for prolonged hours every day can cause self-inflicted sciatica.^[4] Symptoms of numbness and/or pain behind the knee cap are associated with this form of sciatica.

NonSurgical Treatment Options

Chiropractic
Doctors of Chiropractic medicine provide many conservative, non-invasive and drug-free therapies to reduce sciatic nerve symptoms.

Stronger Medication
If pain is severe, the doctor may prescribe a more potent NSAID. Chronic sciatica may require a muscle relaxant and/or anti-depressant medication. Certain anti-seizure and anti-depressant medications are effective in blocking pain messages sent to the brain. Some of these drugs may enhance the body's production of natural pain killers - endorphins.

Epidural Steroid Injection
This type of spinal injection places a steroid (corticosteroid) medication near spinal nerve roots. Steroids reduce inflammation and can help to ease back and leg pain. An epidural steroid injection may provide pain relief for several months or longer.

Structured Physical Therapy Program
Physical therapy and rehabilitation include passive treatments and therapeutic exercises customized to meet the patient's individual needs. Physical therapists work one-on-one with the patient to reduce pain, increase flexibility, and build strength.

Sacroiliac joint dysfunction

Another cause of sciatic symptoms is sacroiliac joint dysfunction^{[citation needed]}. Unhealthy postural habits, such as excessive time sitting in chairs, and sleeping in the fetal position, along with insufficient stretching and exercise of the relevant myofascial areas, can lead to both the vertebral and soft tissue problems associated with sciatica .

Trigger points

Main article: Trigger points

Another source of sciatic symptoms is active trigger points of the lower back and the gluteus muscles.^{[citation needed]} In this case, the referred pain is not consequent to compression of the sciatic nerve, though the pain distribution down the buttocks and leg is similar. Trigger points occur when muscles become ischemic (low blood flow) due to injury or chronic muscular contraction. The most commonly associated muscles with trigger points triggering sciatic symptoms are: the quadratus lumborum, the gluteus medius, the gluteus minimus, and the deep hip rotators ^{[citation needed]}.

Pregnancy

Sciatica may also be experienced in late pregnancy, primarily resulting from the uterus pressing on the sciatic nerve, and, secondarily, from the muscular tension and / or vertebral compression consequent to carrying the extra weight of the fetus, and the postural changes inherent to pregnancy.^{[citation needed]}

Diagnosis and treatment

Because of the many conditions which can compress nerve roots and cause sciatica, treatment and symptoms often differ from patient to patient. Diagnostic tests can come in the form of a series of exams a physician will perform. Patients will be asked to adopt numerous positions and actions such as squatting, walking on toes, bending forward and backward, rotating the spine, sitting, lying on back, and raising one leg at a time. Increased pain will occur during some of these activities.

Treatment of the underlying cause of the compression is often the most effective course. When the cause is due to a prolapsed or lumbar disc herniation, research has shown that, with supportive treatment to help relieve pain, 90% of disc prolapse will recover with no specific intervention. Genetics appear to influence the risk of developing disc herniation.

Imaging methods such as MR neurography may help diagnosis and treatment of sciatica. MR neurography has been shown to diagnose 95% of severe sciatica patients, while as few as 15% of sciatica sufferers in the general population are diagnosed with disc-related problems.^[5] MR neurography is a modified MRI technique using MRI software to provide better pictures of the spinal nerves and the effect of compression on these nerves. MR neurography may help diagnose piriformis syndrome which is another cause of sciatica that does not involve disc herniation.^{[citation needed]}

Most cases of sciatica can be effectively treated by one or a combination of the following:

Medication therapies

• Anti-inflammatory medications (i.e. NSAIDs or oral steroids)
• Pain medications (e.g. acetaminophen)
• Epidural steroid injections to deliver local anti-inflammatory agents (and possibly a pain medication) directly to the affected area

Invasive therapies

• Surgery
• Minimally invasive procedure

Minimally invasive procedures

Intradiscal Electrothermoplasty (IDET)

A needle is inserted into the affected disc, guided by x-ray. A wire is then threaded down through the needle and into the disc until it lies along the inner wall of the annulus. The wire is then heated which destroys the small nerve fibers that have grown into the cracks and have invaded the degenerating disc. The heat also partially melts the annulus, which triggers the body to generate new reinforcing proteins in the fibers of the annulus.

Radiofrequency Discal Nucleoplasty (Coblation Nucleoplasty)

A needle is inserted into the affected disc, although instead of a heating wire, a special RF probe (radio frequency) is used. This probe generates a highly focused plasma field with enough energy to break up the molecular bonds of the gel in the nucleus, essentially vaporizing some of the nucleus. The result is that 10-20% of the nucleus is removed which decompresses the disc and reduces the pressure both on the disc and the surrounding nerve roots. This technique may be more beneficial for sciatica type of pain than the IDET, since nucleoplasty can actually reduce the disc bulge, which is pressing on a nerve root. The high-energy plasma field is actually generated at relatively low temperatures, so danger to surrounding tissues is minimized.^[6]

Alternative therapies

The approach to treating Sciatica is to reduce the compressive forces causing the pressure upon the sciatic nerve. This can be accomplished through traction and realignment therapeutic procedures in the case where the sciatica is spinal-related.

• Acupuncture
• Chiropractic manipulation for the restoration of normal joint biomechanics and reduction of histochemical irritation to the involved nerves. ^[7][8][9]
• Massage therapy to the involved lumbopelvic muscles.
• Structural Integration A systematic approach designed to reorganize major joints, and body segments (such as the lower back region and sacrum), while releasing the chronically held tension and torsion patterns. The goal is to achieve a rapid change in structural mechanics and correction of chronic musculoskeletal pain or dysfunction.

See also

• Back pain
• Piriformis syndrome
• Spinal disc herniation
• Laminectomy
• Hemilaminectomy

References

1. ^ Oxford English Dictionary, 2nd Ed. "a1450a Mankind (Brandl)."
2. ^ Spine Health.com
3. ^ Lewis AM, Layzer R, Engstrom JW, Barbaro NM, Chin CT (2006). "Magnetic resonance neurography in extraspinal sciatica". Arch. Neurol. 63 (10): 1469-72. DOI:10.1001/archneur.63.10.1469. PMID 17030664. 
4. ^ BBC News: Is your wallet a pain in the back?
5. ^ Filler, Aaron; Haynes, J., Sheldon, E., Prager, J., Villablanca, J.P., Farahani, K., McBride, D., Tsuruda, J.S., Morisoli, B., Batzdorf, U. & Johnson, J.P. (February 2005). Sciatica of nondisc origin and piriformis syndrome: diagnosis by magnetic resonance neurography and interventional magnetic resonance imaging with outcome study of resulting treatment. 99-115.
6. ^ SpineUniverse: New Sciatica Treatments
7. ^ Cramer GD: Basic and Clinical Anatomy of the spine, spinal cord and ans, St Louis, 1995, Mosby
8. ^ Jeffries B: Facet Joint Injections, Spine: State of the Art Reviews 2:409, 1988
9. ^ Sall JS: The role of inflammation in lumber pain, Spine 20:1821, 1995

External links

• Sciatica - Information for Patients
• Sciatica Health Hub
• What you need to know about sciatica
• Causes of Sciatica

Diseases of the musculoskeletal system and connective tissue (M, 710-739)
Arthropathies	Arthritis (Reactive arthritis, Rheumatoid arthritis, Psoriatic arthritis, Felty's syndrome, Juvenile idiopathic arthritis, Still's disease) - crystal (Gout, Chondrocalcinosis) - Osteoarthritis (Heberden's node, Bouchard's nodes) - acquired deformities of fingers and toes (Boutonniere deformity, Bunion, Hallux rigidus, Hallux varus, Hammer toe) - other acquired deformities of limbs (Valgus deformity, Varus deformity, Wrist drop, Foot drop, Flat feet, Club foot, Unequal leg length, Winged scapula) - Chondromalacia patellae
Systemic connective tissue disorders	Polyarteritis nodosa - Churg-Strauss syndrome - Kawasaki disease - Hypersensitivity vasculitis - Goodpasture's syndrome - Wegener's granulomatosis - Arteritis (Takayasu's arteritis, Temporal arteritis) - Microscopic polyangiitis - Systemic lupus erythematosus (Drug-induced) - Dermatomyositis (Juvenile dermatomyositis) - Polymyositis - Scleroderma - Sjögren's syndrome - Behçet's disease - Polymyalgia rheumatica - Eosinophilic fasciitis - Hypermobility
Dorsopathies	Kyphosis - Lordosis - Scoliosis - Scheuermann's disease - Spondylolysis - Torticollis - Spondylolisthesis - Spondylopathies (Ankylosing spondylitis, Spondylosis, Spinal stenosis) - Schmorl's nodes - Degenerative disc disease - Coccydynia - Back pain (Radiculopathy, Sciatica, Lumbago, Low back pain)
Soft tissue disorders	Myositis - Myositis ossificans (Fibrodysplasia ossificans progressiva) - Synovitis - Tenosynovitis (Stenosing tenosynovitis, Trigger finger, DeQuervain's syndrome) - Bursitis (Olecranon, Prepatellar, Trochanteric) - fibroblastic (Dupuytren's contracture, Plantar fasciitis, Nodular fasciitis, Necrotizing fasciitis, Fasciitis, Fibromatosis) - enthesopathies (Iliotibial band syndrome, Achilles tendinitis, Golfer's elbow, Tennis elbow, Metatarsalgia, Bone spur, Tendinitis) - Myalgia
Osteopathies	Osteoporosis - Pseudarthrosis - Stress fracture - Monostotic fibrous dysplasia - Skeletal fluorosis - Aneurysmal bone cyst - Osteomyelitis - Avascular necrosis - Paget's disease of bone - Algoneurodystrophy - Osteolysis
Chondropathies	Juvenile osteochondrosis (Legg-Calvé-Perthes syndrome, Osgood-Schlatter disease, Köhler disease, Sever's disease) - Tietze's syndrome
See also congenital conditions (Q65-Q79, 754-756)

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
n. - ischias

Nederlands (Dutch)
ischias

Français (French)
n. - sciatique

Deutsch (German)
n. - (Med.) Ischias

Ελληνική (Greek)
n. - (ιατρ.) ισχιαλγία

Italiano (Italian)
sciatica

Português (Portuguese)
n. - ciática (f)

Русский (Russian)
пояснич- но-крестцовый, люмбо-сакральный радикулит, ишиас

Español (Spanish)
n. - ciática

Svenska (Swedish)
n. - ischias

中文（简体） (Chinese (Simplified))
坐骨神经痛

中文（繁體） (Chinese (Traditional))
n. - 坐骨神經痛

한국어 (Korean)
n. - 좌골 신경통, 좌골통

日本語 (Japanese)
n. - 座骨神経痛, 腰痛

العربيه (Arabic)
‏(الاسم) ألم ألنسا أو ألعصب ألوركي‏

עברית (Hebrew)
n. - ‮נשית (כאב עצבים בגיד הנשה, במותן ובירך)‬

If you are unable to view some languages clearly, click here.

To select your translation preferences click here.