Low Back Pain: Is It Picture Perfect?
For many years there has been a controversy about the connection between back pain and what doctors can see on X-rays and other special pictures of the spine. The problem is that about 30% of people without any back pain show abnormal findings on pictures of the spine. Also, some people with severe back pain have entirely normal spine pictures. Is there really a connection between abnormal back pictures and back pain?

A seven-year study showed that there is, in fact, a connection between abnormal spine pictures and low back pain. The study also looked at men who did different types of labor. The results also suggest that the type of work can affect the odds of developing certain types of back pain.

Groups of Finnish machine workers, carpenters, and office workers were examined and questioned about back pain two times, with three years in between examinations. Each man was asked the same set of questions both times and then underwent a magnetic resonance imaging (MRI) study of his lower spine. The men were divided into groups that had no back symptoms, low back pain that stays in the lower back (local back pain), or back pain that moves from the lower spine down into the leg (sciatic pain).
An MRI produces a very clear picture of the bones, discs, and overall structure of the spine. A team of three radiologists (physicians that read imaging tests) checked for signs of abnormal wear and tear (degeneration) or bulging of the discs within the spine. Then the researchers determined whether the men with pain had abnormal MRI pictures. They also looked to see if the type of work made a difference in the men's risk for getting back pain.

The pictures showed that when signs of wear and tear were present on the MRI, the chances of back pain were significantly higher. There was a strong connection between degeneration or bulging on the MRI and sciatic pain. However, the chances of having local low back pain did not seem to be affected by the number of worn, degenerated discs seen on the MRI pictures.

Machine drivers (including bulldozer operators, longshoremen, and heavy equipment operators) do a lot of sitting on large machines that are constantly vibrating. They do not have a lot of opportunities to get up, move, or change position. Occasionally they have to lift heavy materials. These men had the highest risk of all types of back pain. Over 50% of them suffered from sciatic pains.

Carpenters do a lot of lifting, carrying, and moving around on the job. Their chances of having an accident are high due to climbing, uneven work surfaces, and obstacles at the work site. Their chances of having lower back pain were about as high as the machine operators, but far fewer of the carpenters had sciatic pain. Office workers had the lowest chance of having lower back pain.

So researchers concluded that your type of work does indeed affect your risk of back problems. And if you are having low back pain, chances are that a MRI study will show degeneration or bulging discs.
K. Luoma , MD, et al. Low Back Pain in Relation to Lumbar Disc Degeneration. In Spine. February 15, 2000. Vol. 25. No. 4. Pp. 487-492.