The effect of electromyography-triggered electrical stimulation applied to the back extensors muscles on trunk balance and muscle thickness in individuals with complete thoracic spinal cord injury: A randomized controlled trial

Impaired activation of the paraspinal muscles in individuals with complete thoracic spinal cord injury (SCI) can result in trunk instability, difficulty performing functional transfers, and an increased risk of falls. Since trunk control plays a central role in seated balance, it has a substantial impact on the ability to carry out activities of daily living and maintain independence. This study aimed to investigate the effect of electromyography-triggered neuromuscular electrical stimulation (EMG-NMES) applied to multifidus and erector spinae muscles on trunk balance and muscle thickness in individuals with complete thoracic SCI. A randomized controlled trial. A tertiary rehabilitation center in Ankara, Türkiye. Fifteen participants with complete thoracic SCI. Participants were randomized into an experimental group (n = 7) and a control group (n = 8). Both groups were given balance, mobilization, range of motion, and stretching exercises during their hospital stay. EMG-NMES was applied to the trunk muscles of the experimental group during back eccentric exercises 3 times a week for 4 weeks. The control group performed only back eccentric exercises. The primary outcome measures were the trunk control test (TCT) and the modified functional reach test (mFRT). Secondary outcome measures were paraspinal muscle thickness. The primary outcome measures improved significantly more in the experimental group than in the control group. The mean between-group difference in TCT was 1.98 points (95% CI: 0.47-3.49; effect size 0.92; p = 0.014). For mFRT area, the mean difference between groups was 156.63 cm2 (95% CI: 80.6-232.6; effect size 2.30; p < 0.001). In the experimental group, the increase in the thickness of the erector spinae and multifidus muscles was significantly greater (p < 0.05). This study found that a four-week EMG-NMES protocol combined with exercise improved trunk balance and functional reach distance in individuals with complete thoracic SCI.