Sciatica refers to pain that radiates along the path of the sciatic nerve, which branches from your lower back through your hips and buttocks and down each leg. Typically, sciatica affects only one side of your body.

Sciatica most commonly occurs when a herniated disk, bone spur on the spine or narrowing of the spine (spinal stenosis) compresses part of the nerve. This causes inflammation, pain and often some numbness in the affected leg.

Although the pain associated with sciatica can be severe, most cases resolve with non-operative treatments in a few weeks. People who have severe sciatica that's associated with significant leg weakness or bowel or bladder changes might be candidates for surgery.

Pain that radiates from your lower (lumbar) spine to your buttock and down the back of your leg is the hallmark of sciatica. You might feel the discomfort almost anywhere along the nerve pathway, but it's especially likely to follow a path from your low back to your buttock and the back of your thigh and calf.

The pain can vary widely, from a mild ache to a sharp, burning sensation or excruciating pain. Sometimes it can feel like a jolt or electric shock. It can be worse when you cough or sneeze, and prolonged sitting can aggravate symptoms. Usually only one side of your body is affected.

Some people also have numbness, tingling or muscle weakness in the affected leg or foot. You might have pain in one part of your leg and numbness in another part.

When to see a doctor

Mild sciatica usually goes away over time. Call your doctor if self-care measures fail to ease your symptoms or if your pain lasts longer than a week, is severe or becomes progressively worse. Get immediate medical care if:

• You have sudden, severe pain in your low back or leg and numbness or muscle weakness in your leg
• The pain follows a violent injury, such as a traffic accident
• You have trouble controlling your bowels or bladder

Sciatica occurs when the sciatic nerve becomes pinched, usually by a herniated disk in your spine or by an overgrowth of bone (bone spur) on your vertebrae. More rarely, the nerve can be compressed by a tumor or damaged by a disease such as diabetes.

Risk factors for sciatica include:

• Age. Age-related changes in the spine, such as herniated disks and bone spurs, are the most common causes of sciatica.
• Obesity. By increasing the stress on your spine, excess body weight can contribute to the spinal changes that trigger sciatica.
• Occupation. A job that requires you to twist your back, carry heavy loads or drive a motor vehicle for long periods might play a role in sciatica, but there's no conclusive evidence of this link.
• Prolonged sitting. People who sit for prolonged periods or have a sedentary lifestyle are more likely to develop sciatica than active people are.
• Diabetes. This condition, which affects the way your body uses blood sugar, increases your risk of nerve damage.

Although most people recover fully from sciatica, often without treatment, sciatica can potentially cause permanent nerve damage. Seek immediate medical attention if you have:

• Loss of feeling in the affected leg
• Weakness in the affected leg
• Loss of bowel or bladder function

It's not always possible to prevent sciatica, and the condition may recur. The following can play a key role in protecting your back:

• Exercise regularly. To keep your back strong, pay special attention to your core muscles — the muscles in your abdomen and lower back that are essential for proper posture and alignment. Ask your doctor to recommend specific activities.
• Maintain proper posture when you sit. Choose a seat with good lower back support, armrests and a swivel base. Consider placing a pillow or rolled towel in the small of your back to maintain its normal curve. Keep your knees and hips level.
• Use good body mechanics. If you stand for long periods, rest one foot on a stool or small box from time to time. When you lift something heavy, let your lower extremities do the work. Move straight up and down. Keep your back straight and bend only at the knees. Hold the load close to your body. Avoid lifting and twisting simultaneously. Find a lifting partner if the object is heavy or awkward.

During the physical exam, your doctor may check your muscle strength and reflexes. For example, you may be asked to walk on your toes or heels, rise from a squatting position and, while lying on your back, lift your legs one at a time. Pain that results from sciatica will usually worsen during these activities.

Imaging tests

Many people have herniated disks or bone spurs that will show up on X-rays and other imaging tests but have no symptoms. So doctors don't typically order these tests unless your pain is severe, or it doesn't improve within a few weeks.

• X-ray. An X-ray of your spine may reveal an overgrowth of bone (bone spur) that may be pressing on a nerve.
• MRI. This procedure uses a powerful magnet and radio waves to produce cross-sectional images of your back. An MRI produces detailed images of bone and soft tissues such as herniated disks. During the test, you lie on a table that moves into the MRI machine.
• CT scan. When a CT is used to image the spine, you may have a contrast dye injected into your spinal canal before the X-rays are taken — a procedure called a CT myelogram. The dye then circulates around your spinal cord and spinal nerves, which appear white on the scan.
• Electromyography (EMG). This test measures the electrical impulses produced by the nerves and the responses of your muscles. This test can confirm nerve compression caused by herniated disks or narrowing of your spinal canal (spinal stenosis).

If your pain doesn't improve with self-care measures, your doctor might suggest some of the following treatments.

Medications

The types of drugs that might be prescribed for sciatica pain include:

• Anti-inflammatories
• Muscle relaxants
• Narcotics
• Tricyclic antidepressants
• Anti-seizure medications

Physical therapy

Once your acute pain improves, your doctor or a physical therapist can design a rehabilitation program to help you prevent future injuries. This typically includes exercises to correct your posture, strengthen the muscles supporting your back and improve your flexibility.

Steroid injections

In some cases, your doctor might recommend injection of a corticosteroid medication into the area around the involved nerve root. Corticosteroids help reduce pain by suppressing inflammation around the irritated nerve. The effects usually wear off in a few months. The number of steroid injections you can receive is limited because the risk of serious side effects increases when the injections occur too frequently.

Surgery

This option is usually reserved for when the compressed nerve causes significant weakness, loss of bowel or bladder control, or when you have pain that progressively worsens or doesn't improve with other therapies. Surgeons can remove the bone spur or the portion of the herniated disk that's pressing on the pinched nerve.

For most people, sciatica responds to self-care measures. Although resting for a day or so may provide some relief, prolonged inactivity will make your signs and symptoms worse.

Other self-care treatments that might help include:

• Cold packs. Initially, you might get relief from a cold pack placed on the painful area for up to 20 minutes several times a day. Use an ice pack or a package of frozen peas wrapped in a clean towel.
• Hot packs. After two to three days, apply heat to the areas that hurt. Use hot packs, a heat lamp or a heating pad on the lowest setting. If you continue to have pain, try alternating warm and cold packs.
• Stretching. Stretching exercises for your low back can help you feel better and might help relieve nerve root compression. Avoid jerking, bouncing or twisting during the stretch, and try to hold the stretch for at least 30 seconds.
• Over-the-counter medications. Pain relievers such as ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve) are sometimes helpful for sciatica.

Alternative therapies commonly used for low back pain include:

• Acupuncture. In acupuncture, the practitioner inserts hair-thin needles into your skin at specific points on your body. Some studies have suggested that acupuncture can help back pain, while others have found no benefit. If you decide to try acupuncture, choose a licensed practitioner to ensure that he or she has had extensive training.
• Chiropractic. Spinal adjustment (manipulation) is one form of therapy chiropractors use to treat restricted spinal mobility. The goal is to restore spinal movement and, as a result, improve function and decrease pain. Spinal manipulation appears to be as effective and safe as standard treatments for low back pain, but might not be appropriate for radiating pain.

Not everyone who has sciatica needs medical care. If your symptoms are severe or persist for more than a month, though, make an appointment with your primary care doctor.

What you can do

• Write down your symptoms and when they began.
• List key medical information, including other conditions you have and the names of medications, vitamins or supplements you take.
• Note recent accidents or injuries that might have damaged your back.
• Take a family member or friend along, if possible. Someone who accompanies you can help you remember what your doctor tells you.
• Write down questions to ask your doctor to make the most of your appointment time.

For radiating low back pain, some basic questions to ask your doctor include:

• What's the most likely cause of my back pain?
• Are there other possible causes?
• Do I need diagnostic tests?
• What treatment do you recommend?
• If you're recommending medications, what are the possible side effects?
• For how long will I need to take medication?
• Am I a candidate for surgery? Why or why not?
• Are there restrictions I need to follow?
• What self-care measures should I take?
• What can I do to prevent my symptoms from recurring?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

• Do you have numbness or weakness in your legs?
• Do certain body positions or activities make your pain better or worse?
• How limiting is your pain?
• Do you do heavy physical work?
• Do you exercise regularly? If yes, with what types of activities?
• What treatments or self-care measures have you tried? Has anything helped?