Lower back pain seems to be one of those maladies that most of us have to suffer through from time to time, especially as we get older. For some it is a rare problem that comes and goes, but others struggle with ongoing pain that makes it difficult to function at full capacity. Back and lower body pain can be tied to many causes, but there is much that can be done to prevent and alleviate it in most situations. One possible cause of such pain is a condition called sciatica.
What is Sciatica?
Sciatica (sahy-AT-i-kuh) is a condition of pain associated with the sciatic nerve, which is the largest and longest nerve in the entire body. Sciatica is not an illness, but rather a symptom of other conditions that result in pain along the path of the sciatic nerve, which runs from the pelvis through the buttocks and hip area, and down the back of each leg. The pain of sciatica is characterized by a sharp or burning pain that radiates along the nerve, and may be found anywhere along the pathway.
The sciatic nerve is a critical part of the nervous system that controls many of the muscles of the lower legs, and is responsible for providing feeling to the thighs, legs, and feet. It originates at the base of the spinal chord in the lower back, or lumbar region, and eventually ends at the feet. Sciatica is a relatively common complaint, with approximately 40% of individuals experiencing it at some point in their lives. However, only about 1% of sufferers have any sensory or motor problems that accompany their sciatic pain.
Most cases of sciatica are very treatable with noninvasive therapies such as applications of heat and cold, exercise, and physical therapy, and symptoms are usually resolved within four to six weeks. Surgical options are available for severe or chronic sciatica that does not respond well to other treatments.
What Are the Signs and Symptoms of Sciatica?
The most common symptom of sciatica is pain that travels from the lower back, through one buttock, and down the back of the same leg. The pain can be felt anywhere along the route that the sciatic nerve takes, but is most common between the lumbar region and the back of the calf. The degree and type of pain can vary widely between individuals. Descriptions include sharp, burning, aching, or a jolting electric shock. Severity can run the whole gamut, from mild to excruciating. It is progressive with most patients, starting out gradually and worsening over time. However, some folks have experienced sudden onsets of sciatica. The pain can be continuous or intermittent, and is often exacerbated by sudden movements such as coughing or sneezing, walking, or long periods of uninterrupted sitting. It is usually found in only one extremity at a time, but may affect both simultaneously in some cases.
A small minority of patients will also experience other symptoms, such as:
- Tingling or pins-and-needles, usually in the toes or elsewhere in the foot.
- Muscle weakness and/or numbness in the lower legs or feet. Some folks get pain in one part of the leg, and numbness in another.
- A rare condition known as cauda equina syndrome can produce symptoms such as loss of bladder and/or bowel control. This is a serious disorder that requires immediate medical care.
What Are the Causes of Sciatica?
There are many possible causes for sciatica. Some of the more common ones include:
- Lumbrosacral radiculopathy is one of the most common causes of sciatica. It involves the compression of nerves in the lumbar, or lower spine area. These nerves run between the vertebrae, and are the very beginning of the sciatic nerve. The nerves are most often compressed due to a herniated disk. These disks are made of cartilage, and act as shock absorbers for the vertebrae. As we age, the disks tend to become drier and more brittle, and eventually may develop tears that allow the disks to lose the gelatin-like liquid that is found inside. These are then referred to as herniated or ruptured disks. These herniated disks can put pressure on the sciatic nerve, and cause the resulting pain and other symptoms associated with sciatica.
- Back strain is considered the second most common cause of sciatica. When you lift too much weight or use poor lifting form, the muscles of the lower back can be strained, putting pressure on the sciatic nerve.
- Piriformis syndrome: The piriformis muscle runs from the lower spine, is connected to each thighbone (femur), and is associated with the sciatic nerve. As the sciatic nerve runs through the hip area, it shares space with several muscles, one of them being the piriformis. In some individuals, the sciatic nerve actually runs directly through the piriformis muscle. Piriformis syndrome occurs when the muscle becomes tightened or spasms, and puts pressure on the sciatic nerve. The syndrome typically causes pain in the back of the thigh, and is especially common in women who are very active—such as runners and serious walkers.
- Spondylolisthesis is often the result of degenerative disk disease, and happens when one vertebrae slips slightly over another, causing the sciatic nerve to be pinched where it exits the spine.
- Lumbar spinal stenosis: Ever hear the term “bundle of nerves?” Well, that, in essence, is what the spinal chord is. It is protected by the vertebrae, which surround it in the spinal canal. There are thirty-one pairs of nerves that branch off the spinal chord and enable the brain to communicate with the rest of the body. Spinal stenosis causes the spinal canal to be narrowed, putting pressure on the nerve roots found at the point of constriction. If this occurs near the base of the spinal chord, the sciatic nerve may be affected.
- Spinal tumors: Tumors can grow directly in the spine, in the meninges (membranes) of the spinal chord, or in the space between the spinal chord and the vertebrae, the most common site for spinal tumors. As the tumor grows, it can compress the spinal chord or the nerve roots in the area, and cause quite intense back, hip, and lower extremity pain, as well as muscle weakness and numbness in the legs. Severe cases can result in difficulty walking or bladder/bowel incontinence.
- Other causes may include spinal chord trauma such as a blow to the spine or an automobile accident; rarely an injury or illness that directly affects the sciatic nerve; certain medical conditions that can aggravate the sciatic nerve by affecting the bones, joints, and muscles.
- Researchers have discovered an interesting theory that indicates some immune system involvement in sciatica. After a time, certain neurotransmitters and chemicals that are released in response to the pain may sustain a pain message, even after the condition that is causing the sciatica has been healed. This phenomenon can cause “ghost pain,” so to speak, and is rather difficult to treat. Perhaps we will learn more in the future about the mechanics of this, and how to alleviate it.
How is Sciatica diagnosed?
Your health care provider will usually rely heavily on your symptoms and past medical history to pinpoint a diagnosis of sciatica. Certain tests that measure muscle strength and reflexes are often helpful. One particular diagnostic tool called a straight-leg raising test attempts to pinpoint areas of pain as the leg is raised to various levels while extended straight out. This also helps to identify the involvement of any disk problems associated with the pain. It is also important to try to identify any underlying conditions that could be causing the sciatica. One common source of sciatic pain is when one leg is slightly shorter than the other. This can be a birth defect, or the result of trauma.
Sometimes imaging tests are recommended, and they can be appropriate under some circumstances. Magnetic Resonance Imaging (MRI) is the one I would pick if I felt it was necessary. Stay away from computed tomography scans (CT), as these expose you to unusually high levels of radiation (up to five times that of an ordinary x-ray).
What Treatments Are Available for Sciatica?
Mainstream medicine has a bundle of invasive treatments available that are mainly focused on drugs or surgery. As you might suspect, many of these are laden with potential risks. The good news about sciatica is that there are many good options for self-care that can relieve your symptoms without dangerous side effects to be concerned about. Most of the time you will be able to carry on with your daily activities as you undergo these therapies. Severe pain may dictate a day or so of bed rest, but it is not recommended for much longer than that. Too much inactivity can make things worse and not better. Some effective strategies include:
- Cold packs applied to areas of pain can initially result in less inflammation and reduced sensitivity. An ice pack or bag of frozen vegetables wrapped in a towel should be used for no more than twenty minutes at a time, applied at least four times per day.
- After the first 48 hours, switch to a heating pad or hot water bottle. Sometimes alternating between hot and cold applications will help relieve stubborn pain.
- Gentle stretching is an excellent therapeutic measure to both help relieve pain, and to prevent bouts of sciatica from occurring. It can lessen compression on the nerve roots, and help relax tense muscles. Be sure you go slowly, and avoid jerking motions and twisting or bouncing your muscles.
- A routine of regular exercise is a great preventative and therapeutic approach as well. A combination of strength training, aerobics, and stretching helps to strengthen your body and avoid degenerative diseases of the back and spine that can lead to sciatica and other disorders. Physical activity also releases endorphins, hormones that help to block pain signals and also boost your emotional mood.
- Physical therapy is very effective for many folks with a herniated disk or other issues that result in sciatic pain. It can initially reduce acute pain, as well as teach you how to deal with and avoid future or chronic pain. Goals of a physical therapy program include strengthening the muscles that support your back, increasing flexibility, and correcting your posture. You should learn well during your sessions, and make them part of your permanent routine at home.
- Hydrotherapy, which is a fancy name for a good old-fashioned hot bath, is also very useful for many sciatica sufferers. Soaking helps relax muscles and relieve tension that may be contributing to nerve compression.