The sciatic nerve is the largest nerve in the human body and is formed by the union of 5 nerve roots from the lower spine. It passes deep in the buttock and down the back of the thigh all the way to the heel and sole of the foot. The sciatic nerve serves a vital role in connecting the spinal cord with the skin and muscles of the thigh, leg, and foot. It is the longest and widest single nerve in the human body, going from the top of the leg to the foot on the posterior aspect.The sciatic nerve provides the connection to the nervous system for nearly the whole of the skin of the leg, the muscles of the back of the thigh, and those of the leg and foot. It is derived from spinal nerves L4 to S3. It contains fibers from both the anterior and posterior divisions of the lumbosacral plexus.
Sciatic Nerve Pain:
Sciatica is nerve pain from an injury or irritation to the sciatic nerve, which originates in your buttock/gluteal area. The sciatic nerve is the longest and thickest (almost finger-width) nerve in the body. It’s actually made up of five nerve roots: two from the lower back region called the lumbar spine and three from the final section of the spine called the sacrum. The five nerve roots come together to form a right and left sciatic nerve. On each side of your body, one sciatic nerve runs through your hips, buttocks and down a leg, ending just below the knee. The sciatic nerve then branches into other nerves, which continue down your leg and into your foot and toes.
True injury to the sciatic nerve “sciatica” is actually rare, but the term “sciatica” is commonly used to describe any pain that originates in the lower back and radiates down the leg. What this pain shares in common is an injury to a nerve — an irritation, inflammation, pinching or compression of a nerve in your lower back.
What does sciatic nerve pain feel like?
People describe sciatica pain in different ways, depending on its cause. Some people describe the pain as sharp, shooting, or jolts of pain. Others describe this pain as “burning,” “electric” or “stabbing.”
The pain may be constant or may come and go. Also, the pain is usually more severe in your leg compared to your lower back. The pain may feel worse if you sit or stand for long periods of time, when you stand up and when your twist your upper body. A forced and sudden body movement, like a cough or sneeze, can also make the pain worse.
Can sciatic nerve pain occur down both legs?
Sciatica usually affects only one leg at a time. However, it’s possible for sciatica to occur in both legs. It’s simply a matter of where the nerve is being pinched along the spinal column.
Does sciatica occur suddenly or does it take time to develop?
Sciatica can come on suddenly or gradually. It depends on the cause. A disk herniation can cause sudden pain. Arthritis in the spine develops slowly over time.
How common is sciatica?
Sciatica is a very common complaint. About 40% of people in the U.S. experience sciatica sometime during their life. Back pain is the third most common reason people visit their healthcare provider.
Risk factors for sciatica?
- Have an injury/previous injury: An injury to your lower back or spine puts you at greater risk for sciatica.
- Live life: With normal aging comes a natural wearing down of bone tissue and disks in your spine. Normal aging can put your nerves at risk of being injured or pinched by the changes and shifts in bone, disks and ligaments.
- Are overweight: Your spine is like a vertical crane. Your muscles are the counterweights. The weight you carry in the front of your body is what your spine (crane) has to lift. The more weight you have, the more your back muscles (counterweights) have to work. This can lead to back strains, pains and other back issues.
- Lack a strong core: Your “core” are the muscles of your back and abdomen. The stronger your core, the more support you’ll have for your lower back. Unlike your chest area, where your rib cage provides support, the only support for your lower back is your muscles.
- Have an active, physical job: Jobs that require heavy lifting may increase your risk of low back problems and use of your back, or jobs with prolonged sitting may increase your risk of low back problems.
- Lack proper posture in the weight room: Even if you are physically fit and active, you can still be prone to sciatica if you don’t follow proper body form during weight lifting or other strength training exercises.
- Have diabetes: Diabetes increases your chance of nerve damage, which increases your chance of sciatica.
- Have osteoarthritis: Osteoarthritis can cause damage to your spine and put nerves at risk of injury.
- Lead an inactive lifestyle: Sitting for long period of time and not exercising and keeping your muscles moving, flexible and toned can increase your risk of sciatica.
- Smoke: The nicotine in tobacco can damage spinal tissue, weaken bones, and speed the wearing down of vertebral disks.
Is the weight of pregnancy the reason why so many pregnant women get sciatica?
It’s true that sciatica is common in pregnancy but increased weight is not the main reason why pregnant women get sciatica. A better explanation is that certain hormones of pregnancy cause a loosening of their ligaments. Ligaments hold the vertebrae together, protect the disks and keep the spine stable. Loosened ligaments can cause the spine to become unstable and might cause disks to slip, which leads to nerves being pinched and the development of sciatica. The baby’s weight and position can also add pressure to the nerve.
The good news is there are ways to ease sciatic pain during pregnancy, and the pain goes away after birth. Physical therapy and massage therapy, warm showers, heat, medications and other measures can help. If you are pregnant, be sure to follow good posture techniques during pregnancy to also ease your pain.
What causes sciatica?
Sciatica can be caused by several different medical conditions including:
- A herniated or slipped disk that causes pressure on a nerve root. This is the most common cause of sciatica. About 1% to 5% of all people in the U.S. will have a slipped disk at one point in their lives. Disks are the cushioning pads between each vertebrae of the spine. Pressure from vertebrae can cause the gel-like center of a disk to bulge (herniate) through a weakness in its outer wall. When a herniated disk happens to a vertebrae in your lower back, it can press on the sciatic nerve.
- Degenerative disc disease is the natural wear down of the disks between vertebrae of the spine. The wearing down of the disks shortens their height and leads to the nerve passageways becoming narrower (spinal stenosis). Spinal stenosis can pinch the sciatic nerve roots as they leave the spine.
- Spinal stenosis is the abnormal narrowing of the spinal canal. This narrowing reduces the available space for the spinal cord and nerves.
- Spondylolisthesisis a slippage of one vertebra so that it is out of line with the one above it, narrowing the opening through which the nerve exits. The extended spinal bone can pinch the sciatic nerve.
- Osteoarthritis. Bone spurs (jagged edges of bone) can form in aging spines and compress lower back nerves.
- Trauma injury to the lumbar spine or sciatic nerve.
- Tumors in the lumbar spinal canal that compress the sciatic nerve.
- Piriformis syndrome is a condition that develops when the piriformis muscle, a small muscle that lies deep in the buttocks, becomes tight or spasms. This can put pressure on and irritate the sciatic nerve. Piriformis syndrome is an uncommon neuromuscular disorder.
- Cauda equina syndrome is a rare but serious condition that affects the bundle of nerves at the end of the spinal cord called the cauda equina. This syndrome causes pain down the leg, numbness around the anus and loss of bowel and bladder control.
Symptoms of sciatica
The symptoms of sciatica include:
- Moderate to severe pain in lower back, buttock and down your leg.
- Numbness or weakness in your lower back, buttock, leg or feet.
- Pain that worsens with movement; loss of movement.
- “Pins and needles” feeling in your legs, toes or feet.
- Loss of bowel and bladder control (due to cauda equina).
Diagnosis of Sciatica Pain
Straight Leg Test
First, your healthcare provider will review your medical history. Next, they’ll ask about your symptoms.
During your physical exam, you will be asked to walk so your healthcare provider can see how your spine carries your weight. You may be asked to walk on your toes and heels to check the strength of your calf muscles. Your provider may also do a straight leg raise test. For this test, you’ll lie on your back with your legs straight. Your provider will slowly raise each leg and note the point at which your pain begins. This test helps pinpoint the affected nerves and determines if there is a problem with one of your disks. You will also be asked to do other stretches and motions to pinpoint pain and check muscle flexibility and strength.
The FAIR test is a sensitive and specific test for detection if irritation of the sciatic nerve by the piriformis. FAIR stands for flexion, adduction and internal rotation. Also known as piriformis test.
Depending on what your healthcare provider discovers during your physical exam, imaging and other tests might be done. These may include:
- Spinal X-rays to look for spinal fractures, disk problems, infections, tumors and bone spurs.
- Magnetic resonance imaging (MRI) or computed tomography (CT) scans to see detailed images of bone and soft tissues of the back. An MRI can show pressure on a nerve, disk herniation and any arthritic condition that might be pressing on a nerve. MRIs are usually ordered to confirm the diagnosis of sciatica.
- Nerve conduction velocity studies/electromyography to examine how well electrical impulses travel through the sciatic nerve and the response of muscles.
- Myelogram to determine if a vertebrae or disk is causing the pain.
Self-care treatments include:
- Appling ice and/or hot packs: First, use ice packs to reduce pain and swelling. Apply ice packs or bag of frozen vegetables wrapped in a towel to the affected area. Apply for 20 minutes, several times a day. Switch to a hot pack or a heating pad after the first several days. Apply for 20 minutes at a time. If you’re still in pain, switch between hot and cold packs – whichever best relieves your discomfort.
- Taking over-the-counter medicines: Take medicines to reduce pain, inflammation and swelling. The many common over-the-counter medicines in this category, called non-steroidal anti-inflammatory drugs (NSAIDs), include aspirin, ibuprofen (Advil®, Motrin®) and naproxen (Naprosyn®, Aleve®). Be watchful if you choose to take aspirin. Aspirin can cause ulcers and bleeding in some people. If you’re unable to take NSAIDS, acetaminophen (Tylenol®) may be taken instead.
- Performing gentle stretches: Learn proper stretches from an instructor with experience with low back pain. Work up to other general strengthening, core muscle strengthening and aerobic exercises.
Your healthcare provider may prescribe muscle relaxants, such as cyclobenzaprine (Amrix®, Flexeril®), to relieve the discomfort associated with muscle spasms. Other medications with pain-relieving action that may be tried include tricyclic antidepressants and anti-seizure medications. Depending on your level of pain, prescription pain medicines might be used early in your treatment plan.
An injection of a corticosteroid, an anti-inflammatory medicine, into the lower back might help reduce the pain and swelling around the affected nerve roots. Injections provide short-time (typically up to three months) pain relief and is given under local anesthesia as an outpatient treatment. You may feel some pressure and burning or stinging sensation as the injection is being given. Ask your healthcare provider about how many injections you might be able to receive and the risks of injections.
Alternative therapies are increasingly popular and are used to treat and manage all kinds of pain. Alternative methods to improve sciatic pain include spine manipulation by a licensed chiropractor, yoga or acupuncture. Massage might help muscle spasms that often occur along with sciatica. Biofeedback is an option to help manage pain and relieve stress.
Physical therapy and exercise help strengthen and mobilize tissues in the lower back, pelvis, abdomen, buttocks, and thighs.
The goals of physical therapy and exercise in treating the signs and symptoms of sciatica are to:
- Restore pain-free functional movement patterns
- Relieve lower back, buttock, thigh, and leg pain
- Reduce muscle spasm
- Restore function of the lumbar spine and the sacroiliac joint
- Improve mobility of the lower body
- Foster a better healing environment in the lower back
- Promote neurologic adaptations to reduce the perception of pain
- Prevent future pain flareups and reduce fear associated with movement
Commitment and frequency are important attributes to a successful treatment outcome when using physical therapy and exercise for sciatica. Physical therapy may or may not be combined with the use of pain-relieving treatments, such as over-the-counter (OTC) or prescription medications or epidural steroid injections.
Reclining pigeon pose
Pigeon pose is a common yoga pose. It works to open the hips. There are multiple versions of this stretch. The first is a starting version known as the reclining pigeon pose. If you are just starting your treatment, you should try the reclining pose first.
- While on your back, bring your right leg up to a right angle. Clasp both hands behind the thigh, locking your fingers.
- Lift your left leg and place your right ankle on top of the left knee.
- Hold the position for a moment. This helps stretch the tiny piriformis muscle, which sometimes becomes inflamed and presses against the sciatic nerve, causing pain.
- Do the same exercise with the other leg.
Once you can do the reclining version without pain, work with your physical therapist on the sitting and forward versions of pigeon pose.
Sitting pigeon pose
- Sit on the floor with your legs stretched out straight in front of you.
- Bend your right leg, putting your right ankle on top of the left knee.
- Lean forward and allow your upper body to reach toward your thigh.
- Hold for 15 to 30 seconds. This stretches the glutes and lower back.
- Repeat on the other side.
Forward pigeon pose
- Kneel on the floor on all fours.
- Pick up your right leg and move it forward on the ground in front of your body. Your lower leg should be on the ground, horizontal to the body. Your right foot should be in front of your right knee while your right knee stays to the right.
- Stretch the left leg out all the way behind you on the floor, with the top of the foot on the ground and toes pointing back.
- Shift your body weight gradually from your arms to your legs so that your legs are supporting your weight. Sit up straight with your hands on either side of your legs.
- Take a deep breath. While exhaling, lean your upper body forward over your front leg. Support your weight with your arms as much as possible.
- Repeat on the other side.
Knee to opposite shoulder
This simple stretch helps relieve sciatica pain by loosening your gluteal and piriformis muscles, which can become inflamed and press against the sciatic nerve.
- Lie on your back with your legs extended and your feet flexed upward.
- Bend your right leg and clasp your hands around the knee.
- Gently pull your right leg across your body toward your left shoulder. Hold it there for 30 seconds. Remember to pull your knee only as far as it will comfortably go. You should feel a relieving stretch in your muscle, not pain.
- Push your knee so your leg returns to its starting position.
- Repeat for a total of 3 reps, and then switch legs.
Sitting spinal stretch
Sciatica pain is triggered when vertebrae in the spine compress. This stretch helps create space in the spine to relieve pressure on the sciatic nerve.
- Sit on the ground with your legs extended straight out with your feet flexed upward.
- Bend your right knee and place your foot flat on the floor on the outside of your opposite knee.
- Place your left elbow on the outside of your right knee to help you gently turn your body toward the right.
- Hold for 30 seconds and repeat three times, then switch sides.
Standing hamstring stretch
This stretch can help ease pain and tightness in the hamstring caused by sciatica.
- Place your right foot on an elevated surface at or below your hip level. This could be a chair, ottoman, or step on a staircase. Flex your foot so your toes and leg are straight. If your knee tends to hyperextend, keep a slight bend in it.
- Bend your body forward slightly toward your foot. The further you go, the deeper the stretch. Do not push so far that you feel pain.
- Release the hip of your raised leg downward as opposed to lifting it up. If you need help easing your hip down, loop a yoga strap or long exercise band over your right thigh and under your left foot.
- Hold for at least 30 seconds, and then repeat on the other side.
Some sources of sciatica may not be preventable, such as degenerative disk disease, sciatica due to pregnancy or accidental falls. Although it might not be possible to prevent all cases of sciatica, taking the following steps can help protect your back and reduce your risk:
- Maintain good posture: Following good posture techniques while you’re sitting, standing, lifting objects and sleeping helps relieve pressure on your lower back. Pain can be an early warning sign that you are not properly aligned. If you start to feel sore or stiff, adjust your posture.
- Don’t smoke: Nicotine reduces the blood supply to bones. It weakens the spine and the vertebral disks, which puts more stress on the spine and disks and causes back and spine problems.
- Maintain a healthy weight: Extra weight and a poor diet are associated with inflammation and pain throughout your body. To lose weight or learn healthier eating habits, look into the Mediterranean diet. The closer you are to your ideal body weight the less strain you put on your spine.
- Exercise regularly: Exercise includes stretching to keep your joints flexible and exercises to strengthen your core – the muscles of your lower back and abdomen. These muscles work to support your spine. Also, do not sit for long periods of time.
- Choose physical activities least likely to hurt your back: Consider low-impact activities such as swimming, walking, yoga or tai chi.
- Keep yourself safe from falls: Wear shoes that fit and keep stairs and walkways free of clutter to reduce your chance of a fall. Make sure rooms are well-lighted and there are grab bars in bathrooms and rails on stairways.