Use of the surface EMG coactivational pattern for functional evaluation of trunk muscles in subjects with and without low-back pain

Abstract

This study not only examined the differences among coactivational activities of eight trunk muscles in static holding tasks between normal subjects and low-back pain (LBP) patients, but also selected an evaluation task for LBP patients from the experiment. In a study of 87 subjects, 47 with and 40 without LBP, eight channels of EMG were recorded using a multichannel EMG system. Surface IEMG signals of four right- and left-trunk muscles (rectus abdominis, external oblique, erector spinae, and latissimus dorsi) were obtained in static holding tasks. Trunk muscle groups have different muscle coactivational patterns in functional posture of load holding. For erector spinae muscles, more significant IEMG pattern changes occurred than other trunk muscles between LBP patients and normal subjects in static holding tasks. Using surface IEMG of erector spinae muscle in static holding task can discriminate LBP patients from normal subjects. Relevance to industry Back and overexertion injuries are of relevant concern in industry. This study examined the feasibility of using surface EMG to measure muscle coactivation in functional posture of load holding. This evaluation method could be continuously used to screen workers for reducing back injuries in industry.