Effect of whole-body vibration exercise in preventing falls and fractures: a systematic review and meta-analysis

Abstract

Objective: To investigate the effect of whole-body vibration exercise (WBV) on fracture risk in adults ≥50 years of age.

Design: A systematic review and meta-analysis calculating relative risk ratios, fall rate ratio and absolute weighted mean difference using random effects models. Heterogeneity was estimated using I² statistics, and the Cochrane Collaboration's risk of bias tool and the GRADE approach were used to evaluate quality of evidence and summarise conclusions.

Data sources: The databases PubMed, Embase and the Cochrane Central Register from inception to April 2016 and reference lists of retrieved publications.

Eligibility criteria for selecting studies: Randomised controlled trials examining the effect of WBV on fracture risk in adults ≥50 years of age. The primary outcomes were fractures, fall rates and the proportion of participants who fell. Secondary outcomes were bone mineral density (BMD), bone microarchitecture, bone turnover markers and calcaneal broadband attenuation (BUA).

Results: 15 papers (14 trials) met the inclusion criteria. Only one study had fracture data reporting a non-significant fracture reduction (risk ratio (RR)=0.47, 95% CI 0.14 to 1.57, P=0.22) (moderate quality of evidence). Four studies (n=746) showed that WBV reduced the rate of falls with a rate ratio of 0.67 (95% CI 0.50 to 0.89, P=0.0006; I²=19%) (moderate quality of evidence). Furthermore, data from three studies (n=805) found a trend towards falls reduction (RR=0.76, 95% CI 0.48 to 1.20, P=0.24; I²=24%) (low quality of evidence). Finally, moderate to low quality of evidence showed no overall effect on BMD and only sparse data were available regarding microarchitecture parameters, bone turnover markers and BUA.

Conclusions: WBV reduces fall rate but seems to have no overall effect on BMD or microarchitecture. The impact of WBV on fractures requires further larger adequately powered studies. This meta-analysis suggests that WBV may prevent fractures by reducing falls.

Prospero registration number: CRD42016036320; Pre-results.

Keywords: accidental falls; exercise; fractures; meta-analysis; wbv; whole-body vibration.

Figure 1

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow diagram presenting the literature searches and the included studies.

Figure 2

The risk of bias assessment.

Figure 3

Effect of WBV on the relative risk of experiencing a fracture. WBV, whole-body vibration.

Figure 4

Forest plot of the effect of WBV. (A) The rate ratio of the fall rate/person-years between the WBV and control group. (B) The RR of experiencing one or more falls. Area of each square is proportional to study weight in meta-analysis and horizontal lines represent exact 95% CIs. Diamonds represent pooled effect estimates from random effects meta-analysis. RR, risk ratio; WBV, whole-body vibration.

Figure 5

The effect of WBV exercise in forest plots on (A) areal BMD of the lumbar spine with weighted mean difference and 95% CI, divided in subgroups with vertical vibration and side-alternating vibration, (B) areal BMD in total hip with weighted mean difference and 95% CI, (C) volumetric BMD of the distal tibia with weighted mean difference with 95% CI and (D) WBVs effect on volumetric BMD of the distal radius with weighted mean difference and 95% CI. Area of each square is proportional to study weight in meta-analysis and horizontal lines represent exact 95% CI. Diamonds represent pooled effect estimates from random effects meta-analysis. BMD, bone mineral density; WBV, whole-body vibration.

Figure 6

Presents the effect of WBV exercise on bone resorption markers in forest plot with CTX and the reported effect on bone formation marker amino terminal P1NP. Area of each square is proportional to study weight in meta-analysis and horizontal lines represent exact 95% CIs. Diamonds represent pooled effect estimates from random effects meta-analysis. CTX, carboxy-terminal collagen cross-link; P1NP, propeptide of type I collagen; WBV, whole-body vibration.