سید مجید علوی مهر

Background: Low back pain is a common musculoskeletal condition that can impact a person's ability to walk and move comfortably. Pronated foot posture has been suggested as a potential contributor to low back pain, and this study examines its impact on muscle activity during gait in individuals with low back pain. Aim: This study aimed to investigate whether pronated foot alters the activity timing of trunk and lower limb muscles during gait in low back pain patients. Materials and Methods: The sample of this study included 32 men with low back pain and pronated foot. Participants were divided into control (n=15, with foot pronated only) and experimental (n=17, with both low back pain and foot pronated) groups. The experimental group did resistance training with Thera-band for 12 weeks, 3 sessions per week. A wireless electromyography system with 9 pairs of bipolar surface electrodes was used to record the electromyography activity timing of back and lower limb muscles (sample rate: 2000 Hz). Two-way ANOVA was used for statistical analysis. Results: Significant between-group differences were found at baseline onset of EMG activity timing for gastrocnemious medialis ( P <0.001), gluteus medius ( P <0.001) and erector spinae at 3rd lumbar vertebral level ( P =0.001) muscles. Results indicated significant main effects of “Time” for erector spinae at 3rd lumbar vertebral level offset ( P =0.023), significant main effects of “group” for tibialis anterior offset ( P = 0.039) and for erector spinae at 3rd lumbar vertebral level offset ( P = 0.010). Conclusion: The selected training program changed the timing of erector spinae at 3rd lumbar vertebral level in older adults with both low back pain and pronated feet during walking.