Effect of low-magnitude, high-frequency mechanical stimulation in the rat osteoporosis model

Introduction: Non-pharmacological treatment options as physical exercise are an essential corner stone in the treatment of osteoporosis. In this study, the effects of low-magnitude, high-frequency mechanical stimulation, in the form of whole-body vertical vibration (WBVV) on vertebra bone quality and density were evaluated using an osteoporotic rat model. Methods: Sixty female Sprague Dawley rats were tested for this study. At the age of 3 month they were ovariectomized or sham operated. Each group was divided into two subgroups. 3 months later one of the subgroups received WBVV at 90Hz two times a day, each for 15min, for 30 days. The other group got no treatment. After the vibration treatment, the rats were sacrificed and we evaluated histomorphometric parameters, bone strength and bone mineral density (BMD) of lumbar vertrebrae. Results: WBVV significantly improved trabecular and cortical bone quality in all histomorphometric parameters. Biomechanical properties, in terms of yield load and stiffness of the bone, improved significantly by WBVV. The maximum load showed higher but non-significant changes in mean values. The ash-BMD index showed significant differences between treated and untreated rats. Conclusion: Using low-magnitude, high-frequency mechanical stimulation, in the form of WBVV demonstrated an enhancement of bone quality, bone strength and bone mass. This non-pharmacological treatment showed potential for the treatment of osteoporosis. Further studies are needed to evaluate this new treatment option and potential side effects.2020-08-0