Spinal performance and functional impairment in postmenopausal women with osteoporosis and osteopenia without vertebral fracture

Previous studies have paid much attention to the impact on functional impairment or quality of life from vertebral fractures secondary to osteoporosis, but little research has addressed the function of osteoporotic women without fractures. The purposes of this study were: (1) to describe spinal performance and functional impairment in postmenopausal women with osteoporosis and osteopenia without vertebral fracture, and (2) to investigate the relationship between them. Thirty postmenopausal women diagnosed as having osteoporosis or osteopenia were recruited who fulfilled the following criteria: (1) menopause for at least 6 months; (2) no vertebral fracture; (3) no medication that would interfere with calcium intake. Measurements included assessment of functional impairment and spinal performance including trunk extension/flexion isokinetic strength, spinal range of motion (ROM) and movement velocity in three planes (sagittal, frontal and transverse). The results showed that spinal ROM and velocity were significantly reduced in the osteoporosis group compared with the osteopenia group (p < 0.05), but no significant difference in trunk strength was shown. Functional impairment level showed a slight difference between the two groups (p = 0.042). There was a significant correlation between spinal ROM and motion velocity with bone mineral density; however, functional impairment correlated with motion velocity only in the transverse plane (trunk rotation) (p < 0.05). Spinal strength did not show any correlation with other parameters. It was concluded that spinal motion performance declined and functional impairment increased in relation to the severity of bone mineral loss in postmenopausal women without vertebral fracture, but their physical performance was not correlated with functional impairments.