Effects of tendon vibration during one-legged and two-legged stance in elderly individuals

Abstract

The purpose of this study was to analyze the effects of vibration of the tibialis anterior and Achilles tendons during one-legged and two-legged stance in young and elderly individuals. Sway in the center of pressure (COP) and plantar pressure was observed in four vibration conditions, which included single vibration, combined vibration and non-vibration applied to the tibialis anterior and/or Achilles tendons of the supporting leg. For single vibration, whole-body tilts were directed backward and forward according to the location of the vibration. In combined vibration, very small amplitude body shifts were observed. Using combined vibration of the tibialis anterior and Achilles tendons, the decrease in the COP sway may improve the ability to balance during onelegged stance in elderly individuals. In particular, the decrease in COP sway may improve the ability to balance during one-legged stance by combined vibration in elderly subjects. These findings are important for the use of somatosensory information processing to regulate postural adjustments in the elderly

The Focal Mechanical Vibration for Balance Improvement in Elderly – A Systematic Review

“…Most of the included studies [26][27][28][29][30][31] featured a control group of similar age, except for Yu et al 32 and Ehsani et al, 33 in which the elderly treatment group was compared with healthy young people. These 2 studies sought to explain how and why vibration conditions could affect balance control in the elderly population compared with young adults.…”

“…Ehsani et al 33 only used evaluation scales to stratify the sample, based upon the Center for Disease Control and Prevention's STEADI Risk for Falling Assessment questionnaire, 34 and administered a visual analog pain scale for the lower extremities (VAS-10), 35 during a 2-week period prior to the visit and at the time of the visit, and administered the short Falls Efficacy Scale-International (Short FES-I) to assess the fear of falling. 36 When assessing balance as the primary outcome, 4 studies Bellomo et al, Filippi et al, Wanderley et al, and Yu et al [26][27][28][29][30][31][32] used balance platforms to evaluate postural stability by calculating body sway relative to CoP displacement. In contrast, Ehsani et al 33 used a wearable motion sensor (a tri-axial gyroscope designed to estimate 3-dimensional ankle and hip angles) to calculate the center of gravity (CoG).…”

“…Tankisheva et al did not report any improvements in muscle strength or physical performance assessment, 30 whereas Ehsani et al detected improvements in balance after 1 month of followup. 33 Given the discordant results between the only 2 studies that used low-frequency FV parameters (from 25 to 45 Hz) Tankisheva et al and Ehsani et al, [30][31][32][33] we cannot conclude that low-frequency FV has positive effects. However, the limitations and poor quality of some of the included studies must be considered: in fact, this review included 3 articles with a PEDro score of 4 (fair quality), including 2 non-randomized articles (cross-sectional and clinical study) 32,33 and 1 randomized, clinical trial.…”

“…Based on the studies that showed improvements in motor performance and balance, the FV stimulus must selectively stimulate the type Ia futsal afferents, using frequencies at 100 Hz and amplitudes from 0.2 to 0.5 mm. 45 These parameters were used by 5 of the included studies, [27][28][29][30][31][32] whereas type Ib and II afferent fibers can be recruited when larger amplitudes are used. 46 Several receptor structures have been reported to be sensitive to vibratory stimuli.…”

“…In contrast, Bellomo et al 26 used 300-Hz stimulations with high-intensity frequencies and observed improvements; however, this study did not include long-term follow-up. Unusual parameters were reported for the studies performed by Tankisheva et al and Ehsani et al [30][31][32][33] who applied a frequency of 30-45 Hz. Tankisheva et al did not report any improvements in muscle strength or physical performance assessment, 30 whereas Ehsani et al detected improvements in balance after 1 month of followup.…”