title: Effects of 18-month low-magnitude high-frequency vibration on fall rate and fracture risks in 710 community elderly--a cluster-randomized controlled trial.
abstract: This study is a prospective cluster-randomized controlled clinical trial involving 710 elderly subjects to investigate the long-term effects of low-magnitude high-frequency vibration (LMHFV) on fall and fracture rates, muscle performance, and bone quality. The results confirmed that LMHFV is effective in reducing fall incidence and enhancing muscle performance in the elderly.
  
  
  BACKGROUND
  Falls are direct causes of fragility fracture in the elderly. LMHFV has been shown to improve muscle function and bone quality. This study is to investigate the efficacy of LMHFV in preventing fall and fractures among the elderly in the community.
  
  
  METHODS
  A cluster-randomized controlled trial was conducted with 710 postmenopausal females over 60 years. A total of 364 participants received daily 20 min LMHFV (35 Hz, 0.3 g), 5 days/week for 18 months; 346 participants served as control. Fall or fracture rate was taken as the primary outcome. Also, quadriceps muscle strength, balancing abilities, bone mineral density (BMD), and quality of life (QoL) assessments were done at 0, 9, and 18 months.
  
  
  RESULTS
  With an average of 66.0% compliance in the vibration group, 18.6% of 334 vibration group subjects reported fall or fracture incidences compared with 28.7% of 327 in the control (adjusted HR = 0.56, p = 0.001). The fracture rate of vibration and control groups were 1.1 and 2.3 % respectively (p = 0.171). Significant improvements were found in reaction time, movement velocity, and maximum excursion of balancing ability assessment, and also the quadriceps muscle strength (p < 0.001). No significant differences were found in the overall change of BMD. Minimal adverse effects were documented.
  
  
  CONCLUSIONS
  LMHFV is effective in fall prevention with improved muscle strength and balancing ability in the elderly. We recommend its use in the community as an effective fall prevention program and to decrease related injuries.
authors.affiliation: Department of Orthopaedics and Traumatology, 5/F, Clinical Sciences Building, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China.
authors.forename: K S
authors.initials: KS
authors.lastname: Leung
authors.forename: C Y
authors.initials: CY
authors.lastname: Li
authors.forename: Y K
authors.initials: YK
authors.lastname: Tse
authors.forename: T K
authors.initials: TK
authors.lastname: Choy
authors.forename: P C
authors.initials: PC
authors.lastname: Leung
authors.forename: V W Y
authors.initials: VW
authors.lastname: Hung
authors.forename: S Y
authors.initials: SY
authors.lastname: Chan
authors.forename: A H C
authors.initials: AH
authors.lastname: Leung
authors.forename: W H
authors.initials: WH
authors.lastname: Cheung
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control*; D000368:Aged; D015519:Bone Density / Q000502:physiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D015663:Osteoporosis, Postmenopausal / Q000503:physiopathology / Q000628:therapy; D058866:Osteoporotic Fractures / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D004856:Postural Balance / Q000502:physiology; D011446:Prospective Studies; D052097:Quadriceps Muscle / Q000502:physiology; D011788:Quality of Life; D012307:Risk Factors; D016037:Single-Blind Method; D016896:Treatment Outcome; D014732:Vibration / Q000009:adverse effects / Q000627:therapeutic use*