‘Sciatica’ describes persistent pain felt along the sciatic nerve. This nerve runs from the lower back down through the buttock and into the lower leg. It is the longest nerve in the body. Pain results when this nerve is compressed or injured. It most commonly results from inflammation, bony enlargement due to arthritis, or a displaced (herniated) disk in the lower spine. Sciatic pain symptoms can be felt at any part of the nerve or along its entire length. Sciatica may take several forms, including:
- Dull or sharp pain in the buttocks area or leg that worsens with standing
- Mild to extreme pain
- Burning sensation
- "Pins and needles" or a tingling sensation down the leg
- Pain that makes it difficult to stand up and lasts for weeks or occurs only “now and then”
- Weakness in the the leg, knee, or foot
- Pain when sneezing or coughing
Activity may make the pain more intense. For some patients, sciatica is worse at night.
Herniated (Slipped) discs account for most cases of sciatica. Discs are rings with tough exteriors and soft insides. They are located between the bones of the spine and act as shock absorbers.
Discs can become weak because of pressure from twisting and bending movements, heavy lifting, bad posture, pregnancy, obesity or other conditions that place strain on them. A weakened disc may herniate (bulge out). If the bulge pushes up against the sciatic nerve or crushes it, sciatica occurs.
In most cases, sciatica goes away on its own after a few days or weeks, and the patient is able to go back to routine activities.
In order to pinpoint the exact diagnosis, physicians must first determine if evidence of compression or irritation of the spinal nerve root exists. X-rays do not show the nerve or nerve roots; however, MRI scans are utilized if treatment options such as injections or surgery are a possibility. For this reason, a combination of diagnostics is often used. Common diagnostics include:
- X-rays: X-rays show the bones and tissues located in the back and can help pinpoint any fractures or bone abnormalities.
- Computer Tomography (CT scan): CT scans use an X-ray machine and computer to take photos of the legs, thighs, and hips. CT scans use resulting images to depict the sciatic nerve, blood vessels, and muscles. Dyes are sometimes injected into a patient beforehand to help the CT images appear more clearly.
- Myelogram: Although older technology, a myelogram is the only test that can show nerves in a standing posture. This is important if instability is a suspected symptom. This procedure involves an x-ray and the injection of a dye.
- Nerve conduction tests: Nerve conduction tests monitor how nerves near the surface of the skin and in related muscles respond to electrical stimulation. Small electrodes are placed on areas near the buttocks and legs for the most accurate readings.
- Electromyography (EMG): An EMG test measures muscle function and nerve function. It uses electrodes to measure the electrical activity of the muscles in multiple situations.
- Magnetic Resonance Imaging (MRI): MRI scans utilize magnets and a computer in order to take photos of the hips, legs, and thighs. This tool can show damage in muscles, bones, nerves, and blood vessels. Much like CT scans, dye is sometimes used to improve imaging.
Once the pain of sciatica passes, there are exercises, stretches and other measures that may prevent it from returning. Your doctor may refer you to a physical therapist to develop a personalized program. Here are some steps you can take in the meantime:
- Practice good posture. Stand up straight with your ears aligned with your shoulders. Align your shoulders with your hips and your buttocks tucked in. Your knees should be bent slightly.
- Do abdominal crunches. These exercises strengthen the abdominal muscles that help to support your lower back. Lie with your back on the floor, hands behind your head and knees bent. Press your lower back to the floor. Lift your shoulders up about 10 inches off the floor and then lower them. Don't go that high if it causes more pain. Repeat 10 to 20 times, once a day.
- Walk/swim. Walking and swimming can help to strengthen your lower back.
- Lift objects safely. Always lift from a squatting position, using your hips and legs to do the heavy work. Never bend over and lift with a straight back.
- Avoid sitting or standing for extended periods. If you sit at work, take regular breaks to stand and walk around. If you must be on your feet, prop one foot on a small block or footrest. Switch feet throughout the day.
- Use proper sleeping posture. Take pressure off your back by sleeping on your side or on your back. Put a pillow under your knees.
- Stretch. Sit in a chair and bend down toward the floor. Stop when you feel just slight discomfort, hold for 30 seconds, then release. Repeat 6 to 8 times.
- Avoid wearing high heels. Shoes with heels that are more than 1 1/2 inches high shift your weight forward, throwing the body out of alignment.
At first, rest may be necessary until inflammation in the nerve is reduced. To keep the patient comfortable, anti-inflammatory drugs or simple pain medications may be taken. Applying heat or cold to the affected area may also help relieve the symptoms.
As soon as possible, the patient should resume being active by going back to work, doing physical therapy, walking, and stretching. This is the best way to reduce inflammation in the sciatic nerve.
Nonoperative treatment may include epidural injections into the spinal canal.
Surgery is recommended only if sciatica becomes overwhelming and lasts for an extended period of time. The surgeon will remove part of the bulging disc so that it is no longer pressing against the nerve.