Quantitative analysis of lumbar muscles performance of patients with lumbar disc herniation based on surface electromyography

The aim of this study was to analyze quantitatively the relationship between surface electromyography (sEMG) signals and the Oswestry Disability Index (ODI) in lumbar disc herniation (LDH) patients. The differences in EMG root mean square (RMS), the correlations among EMG RMS of muscles, and the correlation between EMG RMS of left side muscle and EMG RMS of right side muscle in the healthy group and the LDH group were also explored. We recruited thirty female nurses with LDH and thirty female healthy nurses. They performed maximum voluntary flexion (MVF), while sEMG data were collected from the multifidus muscles (MM), external oblique muscles (EOM) and transverse abdominal muscles (TAM). Results showed that maximum amplitude of the normalized EMG RMS of the MM, EOM and TAM all were associated with the ODI. Mean of maximum amplitude of the normalized EMG RMS was lower in the LDH group than that of the healthy group. Furthermore, for MM and TAM, there were significant differences in maximum amplitude of the normalized EMG RMS between the two groups (P<;0.05). The correlation coefficient between EMG RMS of EOM and EMG RMS of TAM in the LDH group was lower than that of the healthy group. The correlation coefficient between EMG RMS of left side TAM and EMG RMS of right side TAM in the LDH group was lower than that of the healthy group. The result of this study suggested that sEMG can be used to quantitatively access disability of LDH patients. The correlations among EMG RMS of muscles may serve as an objective reference of rehabilitation assessment of LDH patients.