title: Influence of pelvic asymmetry and idiopathic scoliosis in adolescents on postural balance during sitting.
abstract: The effects of pelvic asymmetry and idiopathic scoliosis on postural balance during sitting were studied by measuring inclination angles, pressure distribution, and electromyography. Participants were classified into a control group, pelvic asymmetry group, scoliosis group, and scoliosis with pelvic asymmetry and then performed anterior, posterior, left, and right pelvic tilting while sitting on the unstable board for 5 seconds to assess their postural balance. Inclination and obliquity angles between the groups were measured by an accelerometer located on the unstable board. Pressure distribution (maximum force and peak pressure) was analyzed using a capacitive seat sensor. In addition, surface electrodes were attached to the abdominal and erector spinae muscles of each participant. Inclination and obliquity angles increased more asymmetrically in participants with both pelvic asymmetry and scoliosis than with pelvic asymmetry or scoliosis alone. Maximum forces and peak pressures of each group showed an asymmetrical pressure distribution caused by the difference in height between the left and right pelvis and curve type of the patients' spines when performing anterior, posterior, left, and right pelvic tilting while sitting. Muscle contraction patterns of external oblique, thoracic erector spinae, lumbar erector spinae, and lumbar multifidus muscles may be influenced by spine curve type and region of idiopathic scoliosis. Asymmetrical muscle activities were observed on the convex side of scoliotic patients and these muscle activity patterns were changed by the pelvic asymmetry. From these results, it was confirmed that pelvic asymmetry and idiopathic scoliosis cause postural asymmetry, unequal weight distribution, and muscular imbalance during sitting.
authors.affiliation: Department of Healthcare Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do 561-756, South Korea.
authors.forename: Ji-Yong
authors.initials: JY
authors.lastname: Jung
authors.affiliation: Department of Biomedical Engineering, College of Medicine, Chungbuk National University, 52 Naesudong-ro, Seowon-gu, Cheongju, Chungbuk 361-763, South Korea.
authors.forename: Eun-Jong
authors.initials: EJ
authors.lastname: Cha
authors.affiliation: Department of Biomedical Engineering, College of Medicine, Chungbuk National University, 52 Naesudong-ro, Seowon-gu, Cheongju, Chungbuk 361-763, South Korea.
authors.forename: Kyung-Ah
authors.initials: KA
authors.lastname: Kim
authors.affiliation: Department of Electronics and Computer Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, South Korea.
authors.forename: Yonggwan
authors.initials: Y
authors.lastname: Won
authors.affiliation: Department of Rehabilitation Medicine, Chungnam National University Hospital, 220 Gung-dong, Yuseong-gu, Daejeon-si, Chungchungnam-do 301-721, South Korea.
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Bok
authors.affiliation: Department of Rehabilitation Medicine, Chungnam National University Hospital, 220 Gung-dong, Yuseong-gu, Daejeon-si, Chungchungnam-do 301-721, South Korea.
authors.forename: Bong-Ok
authors.initials: BO
authors.lastname: Kim
authors.affiliation: Division of Biomedical Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do 561-756, South Korea.|Research Center of Healthcare & Welfare Instrument for the Aged, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do 561-756, South Korea.
authors.forename: Jung-Ja
authors.initials: JJ
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010384:Pelvic Bones / Q000002:abnormalities* / Q000503:physiopathology*; D004856:Postural Balance; D011187:Posture; D011312:Pressure; D012600:Scoliosis / Q000503:physiopathology*
keywords: Pelvic asymmetry; adolescent idiopathic scoliosis; postural balance; sitting