LOW BACK PAIN
Why does my back hurt and what can I do about it?
By John A. Vallin, MD
INTRODUCTION
In modern society one would be hard-pressed to overestimate the impact of low back pain. The costs, in terms of suffering and money spent, are staggering. At any time in our lives up to 85 percent of us will experience low back pain. Low back pain is the fifth ranking cause of hospital admissions and the third most common cause for surgical procedures in the United States. A 1985 study estimated that 14 percent of the entire population in the United States misses at least one work day per year due to back pain. Some experts calculate that the economic cost of this low back pain epidemic exceeds 100 billion dollars per year. In this article I would like to review with you the basic anatomy of the spine, the causes of low back pain, and how it is commonly treated. I will also provide you with some guidelines on how you can treat your own back pain.
Where does all this back pain come from and who are the people most at risk?
Overall the ratio between men and women is about equal; younger patients with back pain tend to be male and women report more low back pain after the age of 60. Many studies have shown an association between low back pain and poor general health. The number one culprit is obesity, followed by smoking, low levels of physical activity and poor strength and flexibility. Not surprisingly, jobs involving heavy physical labor and participation in certain sports have been associated with higher incidents of low back pain.
Before discussing the various causes of low back pain, let’s take a tour through the anatomy of the lumbar spine (Figure 1).
The spinal column consists of five vertebrae, which are bones that make up the lumbar spine. The spinal canal is a tunnel formed by the vertebrae and contains a sac that holds all of our nerve roots. These nerves carry signals between the brain and our lower extremities including our bowel and bladder. The lamina of each vertebrae forms the back of the spinal canal. A foramen is a small opening between the vertebrae. This is where the nerve leaves the spinal canal. A facet joint is where two vertebrae meet.
Our discs (figure 2) act as cushions between the vertebrae. A disc has a soft gelatinous (nucleus) and a tough outer wall (annulus). Ligaments are bands of tissue that connect the vertebrae.
Constant wear and tear can weaken and damage a disc over time. The disc’s nucleus can then begin to bulge through the annulus and cause a pinched nerve. If the outside of the disc tears, the nucleus will then squeeze through the annulus resulting in a herniation (Figure 3). This type of condition can cause mild to severe back pain and/or leg pain, numbness, tingling and weakness.
As the spine ages and begins to wear out, the discs shrink and get thinner. Unfortunately the discs not only shrink but also expand backward into the spinal canal where the nerves are (Figure 4). As the vertebrae get closer together, spurs form. These boney growths or spurs can form on the vertebrae near the facet joints. This results in narrowing (stenosis) of the foramen or spinal canal.
So what are the most common causes of back pain?
Fortunately about 85 percent of all low back pain is mechanical. It is usually the result of a mild sprain or strain involving the muscles or ligaments in the spine. This is usually the result of prolonged sitting, bending, lifting, twisting, or any other type of physical activity. The good news is that for the most part over 90 percent of the time the symptoms resolve within one-three weeks. In back pain that persists the most common causes arise from the discs, facet joints, sacroiliac joints, and muscles of the low back. In older individuals spurring from degenerative disc disease and arthritis of the facet joints usually cause spinal stenosis. The clinical hallmark of this diagnosis includes low back pain and leg pain while walking with relief when sitting or resting.
What are the red flags of low back pain and when should one be concerned about persistent symptoms?
Night pain, fever, recent history of unexplained weight loss, or a prior history of cancer in the presence of a recent onset of low back pain is very suspicious for a neoplasm. Fever alone or history of IV drug abuse raises the suspicion for infection of the disc or spinal canal. Bowel or bladder dysfunction particularly urinary retention or a sudden onset of weakness in the legs, is suggestive for severe spinal stenosis. This condition is referred to as cauda-equina syndrome and is most commonly the result of a massive midline disc herniation. Severe back pain following trauma may be the result of a compression fracture of the vertebrae.
Now that you are familiar with the anatomy of the spine and the various causes for most low back pain, how do you go about being evaluated and treated should your symptoms persist?
As previously mentioned, most low back pain resolves within a few weeks with rest, activity modification, or over-the-counter analgesics. However, should your back pain persist you should be evaluated by your doctor. Accurate diagnosis requires a complete medical history, physical examination and often laboratory and x-ray studies.
X-rays of your spine reveal bony changes such as arthritis and do not show soft tissue injuries such as sprains or disc herniations. If your doctor suspects injury to the disc or nerves, a magnetic resonance image (MRI) of your spine is typically ordered. This is an advanced image of your spine which outlines in detail the anatomy of your discs, spinal canal, nerves, joints, and bones.
TREATMENT
An array of treatment options are available for the back pain sufferer, some of which are quite effective, while others are not. With respect to medications, your doctor may prescribe or instruct you to take anti-inflammatories or muscle relaxants. Individuals suffering from an acute disc herniation with leg pain as a result of a pinched nerve may benefit from a cortisone injection referred to as an epidural. Epidural injections in the spinal canal appear to speed the rate of recovery in acute injuries due to the potent anti-inflammatory effects. In addition, steroid medication deposit at the site of injury has also been shown to block pain transmission from entering the spinal cord and brain.
The most common non-operative treatment prescribed for back pain sufferers is physical therapy and chiropractic manipulative therapy. Following an evaluation with your therapist, various modalities, such as electrical stimulation, heat, and ice, are typically utilized for acute symptoms. Next would come a progressive exercise program, focusing on abdominal or core stabilization, along with improving spinal and lower extremity flexibility. In addition, a therapist will also review with the patient appropriate posture and mechanics including the do’s and don’ts with respect to standing, walking, driving, sitting, and sleeping. Often exercise programs are tailored to individual needs, and, as the patient improves, more advanced exercises are given. (See below some of the most common core exercises that are taught in our office practice.)
Chiropractic manipulative therapy has also been shown to be an effective treatment for low back pain. Some studies have shown that combining manipulative therapy with stretching, exercises and steroid injections can achieve greater gains in pain reduction and reduce disability than usual care. There is moderate evidence that spinal manipulation can also be effective in treating chronic nonspecific low back pain.
People can also take advantage of complementary therapies, such as massage, acupuncture, acupressure, yoga, Pilates, Tai chi, meditation, to name only a few.
Aside from going to a provider for treatment, what can I do when my back is hurting?
Unfortunately there is no simple solution to back pain. Although your doctor or health care provider can guide you on the road to recovery, a healthy, pain-free back is almost always up to you. The best advice that I can give is common sense, and I am sure you have heard it many times before: Lose weight, stop smoking, and exercise!
When an overweight individual injures his back, it is much harder to treat. A large pendulous abdomen results in a swayback and places excessive mechanical strain on the facet joints leading to premature arthritis. As a result of this poor posture, the low back is subjected to excessive strain making it more vulnerable to injury.
Smokers also have a very high incidence of low back pain. Nicotine has been shown to inhibit the formation of collagen, which is the building block of all of our tissues including the spine. Last but not least, it is critical for anybody with back pain to begin an independent exercise program. This is typically taught by your physical therapist. This would include cardiovascular reconditioning, improving flexibility through various stretching exercises, and core strengthening. Early mobilization and appropriate exercise facilitate the healing process, increases strength, flexibility, and endurance. Core exercise and stretching will also help to support your back in a balanced and stable position.
Back pain sufferers should also be cognizant of appropriate posture and mechanics at all times. It is important to avoid frequent to continuous bending, lifting and twisting. When required to lift, use your legs and squat rather than bend forward with your knees straight. Walk with good posture, keeping your head high, your chin tucked in, and your feet straight ahead. Wear comfortable low heeled shoes. When sitting in a car, move your seat forward to keep your knees level with your hips and sit up straight. A lumbar roll placed in the small of your back may also help with prolonged driving.
When sitting for extended periods of time, try to pick an appropriate orthopedic chair low enough to place both feet on the floor with your knees level with your hips. As a general rule of thumb a good night’s sleep on a firm mattress is more supportive for your lumbar spine. It may also be more comfortable to sleep on your side with your knees bent or on your back with a pillow under or between your knees.
In summary, it is important to remember that low back pain is a symptom and not a disease. The good news is that in the majority of cases low back pain resolves within a few weeks. For those with chronic symptoms, it will be incumbent upon the individual to take charge of their own back pain. Restoring the health of your spine takes effort; it won’t happen overnight. It is important to stay fit and trim and exercise regularly. If you are opposed to a gym, walking and swimming are excellent forms of exercise as well. Those seeking a “quick fix” to their chronic back problem are usually disappointed. Those who take an active role in the care of their back usually succeed and are able to successfully return to work and their normal activity levels without undue disability.
So if you ever develop back pain, and most of you will, don’t despair. If you get evaluated by a qualified health care professional and follow some of the basic principles outlined in this article, I am confident you too will be successful in conquering your aching back.
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