Evaluation of the association between osteoporosis and postural balance in postmenopausal women

Abstract

The incidence of osteoporosis has been increasing, as have fractures resulting from falls. Postural balance was evaluated in postmenopausal women with and without lumbar osteoporosis. One hundred and twenty-six postmenopausal women aged 55-65 years were evaluated and separated into two groups according to the bone mineral density values of their lumbar spine: the osteoporosis group and the control group, paired by age (P = 0.219) and physical activity (P = 0.611). There was no difference between the groups (P = 0.139) regarding falls reported in the previous 12 months. Functional mobility was evaluated through the Timed Up and Go Test. Postural balance was evaluated using a portable force platform in standard standing position, with eyes open and closed, for 60s. Muscle strength was evaluated through an isokinetic dynamometer. This study shows that there is no difference in knee muscle strength and functional mobility (P = 0.121), postural balance with eyes open [mediolateral displacement (P = 0.286) and mean velocity of the center of pressure (COP) (P = 0.173)] and with eyes closed [mediolateral displacement (P = 0.163), and the mean velocity of displacement of the COP (P = 0.09)] in both groups. Subjects reporting falls had greater mediolateral displacement (P = 0.028) in both groups. Postmenopausal women aged between 55 and 65 years do not present changes in postural balance irrespective of lumbar osteoporosis. Greater COP mediolateral displacement is related to the occurrence of falls in postmenopausal women in the previous year.

Keywords: Falls; Muscle strength; Osteoporosis; Postmenopause; Postural balance.