Back pain is one of the most common complaints treated by physicians. Nearly 4 out of 5 people will experience back pain at some time in their life. The vast majority of these cases do not have a definable cause for their pain. This is an important, common problem and the annual cost of treating this pain runs in the tens of billions of dollars.

Back pain can develop in association with a number of causes, including muscle strain, injury to the back, overuse, muscle disorders, pressure on a nerve root, poor posture, and many others. Pregnant women, smokers, construction workers, and people who perform repetitive lifting all have increased risk of back pain. (See also low back pain).