Visual feedback using a smart-phone mirroring system influences trunk muscle activity and kinematics of the trunk and pelvis in healthy and chronic low-back pain groups during arm and leg lift in quadruped position

BACKGROUND: Inappropriate motor patterns such as incorrect roll out of the pelvis should be avoided during stabilization exercise in patients or also in healthy individuals. OBJECTIVE: To investigate the effects of visual feedback (VF) on internal oblique (IO), external oblique (EO), multifidus (MF), and erector spinae (ES) and the kinematics of the trunk and pelvis between healthy and chronic low back pain (CLBP) groups during arm and leg lift in quadruped (ALLQ) position. METHODS: Ten apparently healthy subjects and 10 patients with CLBP performed ALLQ position with and without VF while being monitored using sEMG and a motion analysis system. RESULTS: In comparison to non-VF condition, a VF was associated with a significant increase in the EMG activity of both IOs, decrease in MF and decrease in right ES in the CLBP. Right ES activity significantly increased in the CLBP when VF was not present. Axial rotation of the pelvis decreased in the healthy group with VF. CONCLUSION: VF applied through wireless smart-phone mirroring system has a selective positive effect on trunk muscles and pelvic movement and may be beneficial for CLBP patients. Further research is necessary to explore this novel approach to muscle and segment action.