Recent research has suggested spinal manipulation may have a direct neurophysiological effect on pain perception through dorsal horn inhibition. This study has aimed to add this literature by investigating whether spinal manipulation hypoalgesia was local to anatomical areas innervated by the lumbar spine, correlated with psychological variables, greater than hypoalgesia from physical activity and different for A-delta and C-fiber mediated pain perception. Asymptomatic subjects were randomized to ride a stationary bicycle, perform lumbar extension exercise, or receive spinal manipulation. A hypoalgesic response was recorded following spinal manipulation but the results were only significantly different for C-fiber mediated pain perception compared with stationary bicycle riding.
BMC Musculoskeletal Disorders, 2006, 7:68, online.