Understanding Low Back Pain

Article written by Eeric Truumees, MD

Low back pain is one of the most common reasons why adults in North America visit their doctor or miss work. Some estimate that as many as 70% of us will have at least one major episode of debilitating low back pain during their lifetime. Why? No one is really sure why back problems are so common, but there are a number of theories. First is the evolutionary theory that suggests that because we started walking upright late in our evolution, our backs are not as strong as other areas of the body. Others suggest that back injuries are common because: we weigh too much, we don’t exercise enough, we don’t use proper technique when lifting, or we are genetically programmed to have disk problems.

In fact, there are many types of low back pain and each probably has several factors contributing to it. Among the most common causes of back pain are muscular problems (lumbar strain) and disc degeneration. At least three quarters of back problems involve the muscles and may be related to a lifting injury, poor posture, improper sleeping position, or chronic overuse. These problems often build up gradually over a couple of days. They can affect the whole back and are often worst along the waist line, where the large back muscles attach to the pelvis. When muscles hurt, they often hurt worst where they attach to the bone. Muscular back pain tends to get better on its own over a few days. Bed-rest is no longer recommended, but one should limit high stress activities. Careful stretching, heat, massage, and medications like Ibuprofen, Tylenol, or Aspirin may be helpful.

Disc problems tend to cause pain in the middle of the back. While not as common as muscular pain, disc pain is more chronic in nature and can come and go often. Patients with disc pain flare-ups should avoid excessive bending, lifting and twisting. Disc problems may represent degeneration (arthritis) of the disk with back pain alone or there may be an accompanying disc herniation. Here, a piece of the disc breaks off and pinches one of the nerves that goes down the leg. This leg pain (also known as sciatica or radiculopathy) can be very severe or very mild. Like the other common causes of back pain, even sciatica has a high rate of getting better on its own.

Other than muscular and disc problems, there are many other causes of back pain. Pain in the other joints of the spine (the sacroiliac and facet joints, for example) can occur just like pain in the joints of the arms and legs. Back pain can also be due to kidney problems. Symptoms that should lead you to call your doctor include a recent unexplained weight loss, fevers, chills, night-sweats, or pain that doesn’t begin to improve after a few days. More severe symptoms such as an inability to walk, feeling weakness in the arms or legs, bowel or bladder problems, or tearing pain in the middle of the back should probably be evaluated in the emergency room. Certainly, if you have other major medical problems, persistent back pain should be evaluated. Discuss any severe, recurring, or puzzling symptoms with your doctor.

Like so many other medical problems, an ounce of prevention is worth a pound of cure and, toward that end, maintaining appropriate body weight, getting regular exercise, and using proper technique when lifting will decrease how often you injure your back. Stronger backs may also get better faster. Standard recommendations include weight-bearing aerobic exercise (that is walking or cycling, as opposed to swimming) and lumbar flexor muscle strengthening (abdominal crunches and straight leg lifts). When lifting, remember to use your knees and keep the weight close to your body, not far out in front of you.

There are many reasons to quit smoking, and low back problems are another reason. Normally, the discs have a poor blood supply. Nicotine clamps down the blood vessels that supply oxygen and nutrition to the disc making it unable to repair normal wear and tear. Over time, these changes accumulate and the disc can degenerate faster.

If your back pain does not go away or returns frequently, a visit to the doctor is recommended. A careful history and physical examination will often help the doctor tell what kind of back pain you have. Sometimes, we never really do find out the cause of low back pain. X-rays can show the alignment and the amount of arthritis in your back. Magnetic Resonance Imaging (MRI) is a more sophisticated test that shows the nerves and discs. Once a diagnosis has been made, various medications and physical therapy are often recommended. In other patients, various patches, braces, joint injections, or muscle stimulators are used. Only a small percentage of patient with back pain need spine surgery.