Although low back pain is a symptom, according to the NIH Task Force on Research Standards for Chronic Low Back Pain (cLBP), “there is now growing evidence that in its chronic form, it can progress like other chronic pain conditions, beyond a symptomatic state to a complex condition unto itself.” Defined as “low back pain that occurs at least half of the days in the past six months,” symptoms include dull aching, sharp pain and/or tingling or burning sensations in the low back, defined as the lumbar region of the back between the posterior margin of the rib cage and the horizontal gluteal fold. Weakness in the legs or feet may also accompany these symptoms.

With a worldwide lifetime prevalence of approximately 39 percent and a point prevalence of 8.1 percent in American adults, cLBP occurs from adolescence through the elderly. As the Task Force document summarizes, a wide range of inclusion/exclusion criteria and case definitions are used in cLBP research, making study findings difficult to interpret.

This includes cost estimates for cLBP; a 2012 claims database study of nearly 40,000 cLBP patients found the direct annual cost of the disorder to be approximately $96 million,  although other studies reporting simply on “low back pain” estimate the economic burden to be much higher, nearing $100 billion in direct and indirect costs annually.