What Is Sciatica? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Sciatica is not a medical condition on its own, but rather a nonspecific term used to describe a variety of leg or back symptoms as a result of a medical problem, according to an article published in March 2015 in The New England Journal of Medicine. (1,8)

It refers most commonly to nerve pain along the path of the sciatic nerve  — the longest and thickest nerve in the human body, extending from the back of the pelvis down through the back of the thighs to just below the knees. (2,3)

Sciatica is a common manifestation of lumbar (or lumbosacral) radiculopathy, which refers to any disorder affecting the nerve roots in the lower back, often including the sciatic nerve. The terms sciatica and lumbar radiculopathy are sometimes used synonymously, though sciatica may also be referred to as lumbosacral radicular syndrome, nerve root pain, and nerve root entrapment. (4,5,6,7)

Up to 40 percent of adults in the United States experience sciatica at some point in their life. It most often affects people who are in their forties or fifties. (8)

Research suggests sciatica resolves spontaneously (without treatment) for most people, but others experience chronic (long-lasting) sciatica that may require medical intervention, such as physical therapy, spinal injections (for pain), and surgery. (8)

The hallmark symptom of sciatica is pain that radiates from the lower back down the buttock and back of one thigh. Sciatica usually only affects one side of the body at a time, but it can also occur along both sides, depending on where the nerve is affected along the spinal column. (2,3)

But sciatica pain can vary widely from person to person. It may: (2,3,9)

• Travel all the way down the calf and to the foot
• Cause numbness or weakness in the lower back, buttock, leg, or foot
• Feel like "pins and needles," burning, or tingling sensations
• Present as a bad leg cramp with stabbing or electric-like pain

Sciatica pain may worsen: (1,9)

• With movement or after staying still for a while
• After sneezing, coughing, laughing, or straining
• While holding one's breath
• While bending backwards or walking
• At night

Learn More About Signs and Symptoms of Sciatica 

Sciatica originates from an issue with the sciatic nerve, a large nerve that provides innervation and physical sensations to various parts of the skin and muscles of the legs and feet, according to StatPearls. (10)

The sciatic nerve is made up of five nerve roots — two from the lumbar spine (lower back region) and three from the sacrum (the final section of the spine). These nerve fibers converge to form a left and right sciatic nerve, which run down the two sides of the body to the back of the knees. The sciatic nerve then branches into other nerves that continue down into the legs, feet, and toes. (2,10)

Sciatic pain is primarily caused by an injury to the nerve in your lower back region, such as from irritation, inflammation, pinching, or compression of the nerve.

The most common cause of sciatica is a herniated disc in your spine that puts pressure on the sciatic nerve roots. Some research suggests up to 90 percent of sciatica cases stem from herniated discs. (2,7)

Other spinal issues may also cause sciatica, including: (2,8)

• Spondylolisthesis, in which a vertebra slips out of alignment
• Foraminal stenosis or spinal stenosis, conditions marked by a narrowing of the spinal canal
• Synovial cysts in the spine
• Tumors of the spinal column or the nerves
• Degenerative disc disease (natural wear down of the discs)
• Bone spurs from osteoarthritis
• Cysts or inflammation of the arachnoid, one of the membranes that protect the nerves of the spinal cord

Yet there are also other mimickers of lumbar radiculopathy that can produce sciatica-like symptoms, called nondiscogenic sciatica, and other non-spine-related injuries to the sciatic nerve, such as: (2,8,20,21)

• Traumatic injury to the sciatic nerve, such as from a pelvis fracture, hip dislocation, or intramuscular injection to the buttocks
• Piriformis syndrome, a condition resulting from an injury to the piriformis muscle that's located deep in the buttocks
• Herpes zoster or shingles in the lumbar nerves
• Facet hypertrophy or other forms of degenerative disc disease
• Ankylosing spondylitis and sacroiliitis, inflammatory conditions that irritate the joints of the spine and hip
• Pregnancy (1,2,3,15)

There is no singular test that can diagnose sciatica. Instead, diagnosis is based on symptoms (and medical history), a physical examination, and imaging and other tests.

The physical exam, with special attention to your spine and legs, is an important part of sciatica diagnostic process.

Your doctor will conduct a series of physical examination tests that will probe your muscle strength, nerve pain, reflexes, and flexibility. These tests aren't perfect but may help to differentiate potential causes of your sciatica and may reveal if you have: (1,22)

• Difficulty or pain bending the foot inward or down, bending forward or backward, or walking on your toes
• Poor reflexes
• Numbness or decreased physical sensations
• Leg weakness from bending the knee

The physical exam incorporates a number of different leg and foot tests, that can help try to differentiate the potential cause or causes, according to a 2019 article in BMJ, including: (11)

• Straight leg raise test and reverse straight leg raise test to stretch your nerves and see when your pain begins during movement
• Knee extension and ankle flexion to test motor weakness
• Light touches and pin pricks to identify any loss of sensations
• Reflex tests

During this physical exam, your physician will also see if you have any difficulty bending your foot, walking on your toes, and bending forward and backward. (1)

They may also order a number of tests, including any of the following, per the Cleveland Clinic: (2)

• X-rays can see if you have any potential causes of sciatica, including spinal fractures, disc problems, cysts, tumors, and bone spurs. Yet X-ray and other imaging test are not perfect in finding all of these conditions.
• A magnetic resonance imaging (MRI) scan can identify issues that may put pressure on the nerve.
• Nerve conduction tests can see how well electrical impulses travel through the sciatic and others nerve and how your muscles respond.
• A myelogram can help detect problems with the spinal cord, including herniated discs.

However, some experts only recommend these tests if your problem lasts for at least 12 weeks or if you have progressive numbness or weakness or worsening pain. The tests are not recommended for people who have nonspecific low back pain. (11)

Research shows most people with sciatica get better without medical intervention.

In fact, some reports suggest about 80 to 90 percent of people with sciatica get better over time — most often within a few weeks — without surgery. (2,9)

Prognosis of Sciatica

But there is no consensus in the scientific literature regarding sciatica prognosis.

A United Kingdom study, published in The Spine Journal in June 2018, found that 55 percent of participants with back-related leg pain improved after a year. The research also showed that two factors — a longer duration of leg pain and patients believing their sciatica would persist — were associated with a poorer prognosis. (12)

In research published in the journal BMJ Open, which evaluated a group of patients with severe disc related sciatica over five years with either early surgery or six months of conservative (physical therapy) first, researchers found that as much as 8 percent of participants showed no signs of recovery five years after receiving either conservative treatment or surgery. (11,13)

Results suggest that some patients continued to experienced symptoms at five years out that continued but fluctuated over time despite treatment.

A systematic review of patients that underwent spine surgery for sciatica, published in May 2016 in the European Journal of Pain, similarly showed that some people still experience sciatica symptoms and significant impact on their function five years after receiving surgery. (14)

Because sciatica is usually self-resolving, initial treatment is palliative in nature.

Treatment options to relieve sciatica pain include:  (1,2,3,15)

• Applying ice or heat to the painful area, starting with ice for a couple days before switching to heat
• Staying active as opposed to prolonged bed rest
• Avoiding strenuous activities, such as heavy weight lifting, and prolonged sitting or standing
• Taking over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen
• Gently stretching the spine and hamstrings
• Engaging in light activity, such as walking and swimming, as well as exercises to increase core strength
• Practicing good posture

Medication and Nonsurgical Treatment Options

If these practices are not effective, your physician may recommend: (2,7,8,15,16)

• Physical therapy
• Traction therapy or spinal manipulation
• Epidural steroid injections
• Prescription pain relief medication, such as muscle relaxants, anticonvulsants, tricyclic antidepressants, weak opioids, and oral corticosteroids
• Psychological programs, such as cognitive behavioral therapy

Alternative and Complementary Therapies

Integrative, complementary and alternative treatments may also help provide relief. These may include chiropractic treatments, yoga, acupuncture, deep tissue massage, and biofeedback. (2,7,15,23,24) Each has its own potential for benefit, risk, cost and levels of evidence for treatment forms of sciatica. Its best to speak to your primary physician or integrative medicine informed physician or specialist to help guide which therapies may be used alone or in conjunction with your mainstream treatment plans.

Your physician may recommend surgery if you have chronic sciatica, sciatica that does not improve from other treatments, or symptoms that are worsening.

The specific type of surgery you receive depends on the cause of your sciatica. One technique, for example, is a minimally invasive procedure called microdiscectomy to remove fragments of a herniated disc. (2,8)

Some research suggests cannabis could help relieve chronic sciatic pain. For instance, a study published in September 2018 in the journal Neurology found that medical marijuana may help relief chronic nerve pain by modulating the connections in the brain involved in processing pain. (17)

Learn More About Sciatica Treatments

Prevention of Sciatica

It’s not always possible to prevent sciatica.  Risk may be reduced with exercise and maintaining a strong core.

Chronic sciatica, with or without surgical intervention previously, may lead to a few different complications, including: (2,3)

• Increased pain, and chronic pain
• Weakness in your affected leg
• Permanent nerve damage, which can cause loss of feeling in the affected leg
• Loss of bowel or bladder control

If the nerve is seriously damaged, it could lead to foot drop or drop foot, in which you're unable to lift the front of the foot. Foot drop makes normal walking impossible and falls more likely. (2,18)

Research suggests 10 to 40 percent of people experience sciatica in their lifetime.

Most people get it in their forties and sciatica rarely occurs before age 20 unless a traumatic injury is involved. Some other risk factors may include:

• Genetic predisposition
• Strenuous physical activity if you've experience sciatica symptoms before
• Height, if you're in your fifties or sixties (risk increases with height)
• Smoking
• Stress
• Truck driving and machine operating
• Osteoarthritis
• Being overweight

Depression, low socioeconomic status, and poor movement during work may also lead to an increased chance of chronic or recurrent sciatica. (2,7,15)

Because a number of conditions produce sciatica-like symptoms, sciatica may be misdiagnosed as another condition or disease (and vice versa). Conditions similar or related to sciatica include: (8,15,19)

• Piriformis syndrome, which can cause sciatica but can also produce symptoms that mimic sciatica
• Vascular disease
• Peripheral neuropathy
• Peroneal neuropathy
• Herpes zoster, which is caused by varicella zoster, the virus behind shingles and produces severe nerve pain but no rash
• Potts disease or spinal tuberculosis
• Epidural abscess
• Epidural hematoma
• Muscle spasms

Favorite Orgs for Essential Sciatica Info

Spine-Health Knowledge From Veritas: Sciatica

Veritas Health is a consumer health organization and website full of articles written by medical professionals. It has pages on various aspects of sciatica, including causes, symptoms, treatment, and surgical procedures for the condition. Its library of strengthening and stretching exercises may help you get started improving your health.

American Academy of Physical and Rehabilitation (AAPM&R)

AAPM&R is the primary medical society for physical medicine and rehabilitation, also known as physiatry. Founded in 1938, AAPM&R advocates for and provides education about physiatry, and it publishes the peer-reviewed PM&R Journal. The website includes various pages about a number of sciatica-related and sciatica-causing conditions, such as lumbar radiculopathy. It also has a tool to find a PM&R physician.

OrthoInfo by the American Academy of Orthopaedic Surgeons (AAOS)

Developed by AAOS, OrthoInfo provides a wealth of information about injuries and diseases that affect your body's musculoskeletal system, including sciatica. OrthoInfo has guides on various conditions that can cause sciatica, including herniated disc and spinal stenosis, as well as information about recovery and staying healthy.

Favorite Websites for Information About Sciatica Diagnosis and Tests

American Association of Neuromuscular and Electrodiagnostic Medicine

AANEM's goal is to improve the lives of people with neuromuscular diseases. This association can help you better understand some of the tests that physicians may do to diagnose sciatica and other nerve disorders. The website also has a tool to help you find a specialist.

American Chronic Pain Association

Established in 1980, the American Chronic Pain Association offers peer support and education in pain management skills not only to people with pain, but also their family, friends, and health care professionals. The association’s Consumers’ Guide on Practice Guidelines for Low Back Pain explains the process of assessing and diagnosing low-back pain and describes a range of treatments.

Radiological Society of North America

The nonprofit Radiological Society of North America hosts the world’s largest radiology conference and publishes two peer-reviewed journals, Radiology and RadioGraphics. The society's patient information site, RadiologyInfo.org, explains what epidural injections are, why they’re used, and how they work. It also has an in-depth guide about MRIs of the spine.

Our Favorite Sciatica Support Groups

Sciatica Support Group

SupportGroups.com hosts chat groups to discuss a range of physical and mental health issues. On the website, hear from others with sciatic pain, post your own story, and exchange tips for coping with the symptoms.

Drugs.com Sciatica Support Group

Drugs.com is a treasure trove of information about drugs to treat a huge variety of conditions. Its support group page for sciatica contains messages boards that cover dozens of popular questions that focus largely on the use of drugs to treat sciatica.

Spine-Health Forums

Spine-Health's forums cover numerous painful conditions involving the spine, as well as other common musculoskeletal conditions, some of which are associated with sciatica. The forums also contain message boards specifically about chronic pain and low back pain.

Learn More About Sciatica Resources