Electromyographic analysis of core training exercises performed with stable and unstable surfaces in people with Adoloscent Idiopathic Scoliosis (AIS).

Purpose: Adolescent Idiopathic Scoliosis (AIS) is one of the most common spinal disease during growth. Although the role of physical exercise has been previously demonstrated in AIS treatment, a debate still exists about the most efficient exercise setting to approach this problem. Recently, several studies demonstrated that self-correction, core training, instability and balance training exercises decrease Cobb angle and improve AIS. Since trunk muscle activity evidences differences between convex and concave side of the spine, asymmetric exercises seem to obtain better result in improving muscular balance. The aim of this study is to investigate paraspinal muscles activity during core training and balance exercises performed in stable (MAT) and unstable condition (BOSU) in people with AIS. Methods: Five people (2 M and 3 F; age range: 11-15 years) with clinical diagnosis of AIS were recruited in a physiotherapy centre. Muscle activity (EMG) has been recorded with surface electromiography (BTS Free EMG) during 2 balance training and 3 core training exercises using MAT and BOSU. Electrodes were placed bilaterally in T5 (T: Trapezius Ascendens), T10 (ES: Erector Spinae) and L5 (M: Multifidus) area. Balance exercises were 1 leg standing balance with right (MBR) and left (MBL) foot. Core training exercises were Prone Plank (PP), Side Plank on right side (SPR) and left side (SPL). All exercises were performed in static condition using MAT and then BOSU. Data were recorded and analyzed in order to describe EMG differences between MAT and BOSU for left (L) and right (R) side of the body (reference condition: MAT). Results: Global EMG during BOSU exercises showed greater activity compared to MAT for MBR, MBL, PP and SPR (respectively, 213,55%, 230,67%, 107,5 and 120,5%), while SPL evidenced lower values (88%). Higher differences between R and L have been found during BOSU MBL and MBR for M, T and ES muscles related to spine curvature and body perturbation, while PP, SPR and SPL showed differences specially in T muscle using BOSU. Conclusion: Balance and core exercises using unstable surface (BOSU) increase muscle activity in people with AIS. Since 1 leg standing balance requires stability and neuromuscular control, MBR and MBL exercises could enhance asymmetric EMG of paraspinal muscles in order to oppose against trunk sway and perturbation. Consequently, BOSU can be a useful tool for specific training in scoliotic people. References: Czaprowsky D, Afeltowicz A, Gebicka A, Pawiowska P, Kedra A, Barrios C, Hadala M (2014), Abdominal muscle EMG-activity during bridge exercise on stable and unstable surfaces, Physical Therapy in Sport, 15(3): 162-168 Farahpour N, Ghasmi S, Allard P, Sadegh Saba M (2014), Electromyographic responses of erector spinae and lower limb’s muscles to dynamic postural perturbations in patients with adolescent idiopathic scoliosis, Journal of Electromyography and Kinesiology, 24(5): 645-651