Immediate effects of trunk stabilizer muscles training on muscle response time in individuals with non-specific chronic low back pain.

OBJECTIVE: To investigate immediate effects of biofeedback training on motor control performance in participants with nonspecific chronic low back pain. MATERIAL AND METHOD: RCT was conducted. The training group received isolated and co-contraction training of trunk stabilizers in lying on the left side, sitting on stool and sitting on a gymnastic ball, while the control group was asked to rest comfortably on a chair. Trunk muscles response time during rapid arm movement test was recorded using surface electromyography. Two-way ANOVA and Bonferroni post hoc test were used to detect changes within and between groups. RESULTS: In the training group, the trunk muscles response times were significantly decreased after training when compared with those in the control group (p<0.05). CONCLUSION: Trunk stabilizer training has a beneficial effect on motor response time of the trunk muscles. The long-term effects of exercise should be further considered with a larger sample size.

Comparison of musculoskeletal load using two devices for manual height adjustment of the hospital bed.

Objectives. Patient manual handling in bed causes lower back pain (LBP) among Thai nurses. This study aims to develop an extension device for manual height adjustment of the hospital bed, and to evaluate its efficiency in preventing LBP among Thai nurses. Methods. Eleven participants were enrolled for electromyography measurement in eight right muscles. Subsequently, 56 volunteer nurses were recruited by convenience sampling for observational risk assessment by rapid entire body assessment (REBA) and satisfaction evaluation. The characteristics of the participants, percentage of maximum voluntary contraction (%MVC) of each muscle, REBA scores and satisfaction in using the device were analyzed by descriptive statistics, multivariate analysis of variance, paired t test and Wilcoxon signed-rank test, respectively. Results. %MVC values of the six muscles, i.e., biceps brachii, deltoideus, trapezius, latissimus dorsi, erector spinae and hamstring, were found to have a 4-18% decrease. The REBA scores decreased for both left and right when using the extension device, and all participants were more satisfied with the extension device than the hand crank of the hospital bed. Conclusions. The use of the extension device for manual height adjustment of the hospital bed developed from this study helps to prevent LBP among healthcare workers across settings.