The relationship between paraspinal EMG and chronic low back pain.

Two models of the relationship between paraspinal EMG and low back pain have been proposed. Specific predictions arising from these are listed and the literature relating to them reviewed. Recent research on patterns of EMG rather than absolute levels is also discussed. It is concluded that there is no consistent evidence that low back pain patients have elevated paraspinal EMG, or that its reduction is likely to be an active ingredient in biofeedback therapy. Research on paraspinal EMG patterns is still preliminary, and therefore treatment based on their modification is experimental.