Human Evolution, Low Back Pain, and Dual-Level Control

Abstract The Ubiquity of Back Pain “Oh, my aching back!” is a cry familiar to everyone, and for good reason. From 18% to 26% of the general population in urban industrial societies will be experiencing low back pain (LBP) at any one moment in time (the point prevalence rate). Each year, as much as 45% of a population may experience an attack of LBP (the annual prevalence rate). The lifetime prevalence of LBP in urban industrial societies ranges from 50% to 80%. That is, at one time or another, from half to three-quarters of all men and women are likely to experience at least one episode of back pain severe enough to incapacitate them for up to a month. It is not clear that lifetime prevalence is lower in smallscale or less technologically developed societies, as some have stated (Fahrni, 1976). The evidence on that point is equivocal (Anderson, 1987). Most sufferers recover, but 2% or 3% of those afflicted in any society do not fully recover. They continue to experience back pain as a chronic and more or less incapacitating affliction. Almost all of the LBP that creates these remarkable prevalence rates is mechanical in origin, as will be explained below (Allan and Waddell, 1989, Anderson, 1992; Frymoyer, 1990; Papageorgiou and Rigby, 1991).