Effect of whole-body vibration on BMD: a systematic review and meta-analysis

Our systematic review and meta-analysis of randomized controlled trials (RCTs) examining wholebody vibration (WBV) effect on bone mineral density (BMD) found significant but small improvements in hip areal BMD (aBMD) in postmenopausal women and in tibia and spine volumetric BMD in children/adolescents, but not in other BMD measurements in postmenopausal women and young adults. Introduction Animal experiments report anabolic bone changes in response to WBV, but data in humans are limited. Our objective is to conduct a systematic review and meta-analysis of RCTs examining WBV effect on BMD. Methods Eligible RCTs included randomized or quasi-randomized trials, with follow-up of >= 6 months, examining WBV effects on BMD in ambulatory individuals without secondary causes of osteoporosis. The weighted mean differences between WBV and control groups in absolute pre-post change in spine and hip aBMD, and in spine and tibia trabecular volumetric BMD (vBMD) were calculated. Results Eight RCTs in postmenopausal women (five RCTs), young adults (one RCT), and children and adolescents (two RCTs) were included. The regimens were heterogeneous, study durations were relatively short, and available data was mostly per-protocol. In postmenopausal women, WBV was found to significantly increase hip aBMD (0.015 g cm(-2); 95% confidence interval (CI), 0.008-0.022; n=131) versus controls, but not spine aBMD (n=181) or tibia trabecular vBMD (n=29). In young adults, WBV did not increase spine or hip bone mineral content, or tibia trabecular vBMD (n=53). In children and adolescents, WBV significantly increased spine (6.2 mg cm(-3); 95% CI, 2.5-10.0; n=65) and tibia (14.2 mg cm(-3); 95% CI, 5.2-23.2; n=17) trabecular vBMD. Conclusions We found significant but small improvements in BMD in postmenopausal women and children and adolescents, but not in young adults. WBV is a promising new modality, but before recommendations can be made for clinical practice, large-scale long-term studies are needed to determine optimal magnitude, frequency, and duration.