Clinical Interventions in Aging (Sep 2015)
Efficacy of a trunk orthosis with joints providing resistive force on low-back load in elderly persons during static standing
Abstract
Junji Katsuhira,1 Ko Matsudaira,2 Tadashi Yasui,3 Shinno Iijima,4 Akihiro Ito4 1Department of Nursing and Rehabilitation Science at Odawara, International University of Health and Welfare, Odawara, Kanagawa, 2Department of Medical Research and Management for Musculoskeletal Pain, 22nd Century Medical and Research Center, The University of Tokyo, Tokyo, 3Kawamura-Gishi Company, Ltd., Daito-shi, Osaka, 4Graduate School of International University of Health and Welfare, Otawara, Tochigi, Japan Purpose: Postural alignment of elderly people becomes poor due to aging, possibly leading to low-back pain and spinal deformity. Although there are several interventions for treating these conditions, no previous study has reported the effectiveness of a spinal orthosis or lumbosacral orthosis (LSO) in healthy elderly people without specific spinal deformity. We therefore developed a trunk orthosis to decrease low-back muscle activity while training good postural alignment through resistive force provided by joints with springs (here, called the ORF, which stands for orthosis with joints providing resistive force) as a preventive method against abnormal posture and low-back pain in healthy elderly persons. Patients and methods: Fifteen community-dwelling elderly men participated in this study. Participants stood freely for 10 seconds in a laboratory setting under three conditions: without an orthosis, with the ORF, and with an LSO. The Damen corset LSO was selected as it is frequently prescribed for patients with low-back pain. Postural alignment during static standing was recorded using a three-dimensional motion capture system employing infrared cameras. Two force plates were used to record center of pressure. Electromyograms were obtained for bilateral erector spinae (ES), left internal abdominal oblique, and right gluteus medius muscles. Results: Pelvis forward tilt angle tended to increase while wearing the ORF and decrease while wearing the LSO, but these results were not significant compared to no orthosis. Thorax extension angle and thorax angle on pelvis coordinate system significantly increased while wearing the ORF compared to the other two conditions. ES activity significantly decreased while wearing the ORF compared to the other two conditions. Internal oblique activity was significantly smaller while wearing the LSO than with no orthosis. Center of pressure did not significantly differ among the conditions. Conclusion: The ORF significantly improved trunk alignment and decreased ES activity in healthy elderly subjects during static standing. Keywords: muscular activity, center of pressure, standing posture, spine
