Feature of surface electromyography of lumbar erector spinae muscle in fighter pilots with nonspecific

Abstract

Objective To explore objective diagnostic and evaluative surface electromyography (sEMG) feature for the fighter pilots with nonspecific low back pain.Methods The erector spinae muscle sEMG of 39 fighter pilots with nonspecific low back pain (as case group) and 12 pilots without painful symptom (as control group) was measured by ME-6000-T8 electromyograph.All pilots were asked to contract their lumbar muscle steadily and move from an erect to a flexion posture.sEMG signal processing was conducted by MEGAWIN 700046,2.4 software.The fatigue indexes such as median frequency slope (MFs),mean power frequency slope (MPFs),zero crossing rate slope (ZCRs),average electromyography (AEMG) and coordination index flexion extension ratio (FER)were analyzed by SPASS 13.0.Results There were no significant differences between case group and control group with respect of sEMG indexes when isometric contraction of erector spinae muscle was applied.AEMG and FER indexes showed significant difference between groups under erector spinae muscle flexion and extension (t =1.979-5.387,P＜0.05 or P＜0.01).Conclusions Pilots with low back pain show different FER index of sEMG from normal pilots.Their erector spinae muscle sEMG has such feature as increased or decreased amplitude corresponding to the state of flexion and isometric contraction.FER is suggested to be an objective index to evaluate nonspecific low back pain of fighter pilots. Key words: Low back pain; Disease attributes; Electromyography