Site-Specific Transmission of a Floor-Based, High-Frequency, Low-Magnitude Vibration Stimulus in Children With Spastic Cerebral Palsy

Abstract

Objective To determine the degree to which a high-frequency, low-magnitude vibration (HLV) signal emitted by a floor-based platform transmits to the distal tibia and distal femur of children with spastic cerebral palsy (CP) during standing. Design Cross-sectional study Setting University research laboratory Participants 4 to 12 year-old children with spastic CP who could stand independently (n=18) and typically developing children (n=10) participated in the study. Intervention Not applicable Main outcome measures The vibration signal at the HLV platform (~33 Hz and 0.3 g), distal tibia and distal femur was measured using accelerometers. Degree of plantar flexor spasticity was assessed using the Modified Ashworth Scale. Results The HLV signal was greater (p<0.001) at the distal tibia than at the platform in children with CP (0.36±0.06 vs. 0.29±0.05 g) and controls (0.40 ± 0.09 vs. 0.24 ± 0.07 g). Although the HLV signal was also higher at the distal femur (0.35±0.09 g, p<0.001) than at the platform in controls, it was lower in children with CP (0.20±0.07 g, p<0.001). The degree of spasticity was negatively related to the HLV signal transmitted to the distal tibia (rs=−0.547) and distal femur (rs=−0.566) in children with CP (both p<0.05). Conclusions An HLV signal from a floor-based platform was amplified at the distal tibia, attenuated at the distal femur and inversely related to the degree of muscle spasticity in children with spastic CP. Whether this transmission pattern affects the adaptation of their bones to HLV requires further investigation.

The Impact of Whole-Body Vibration Training on Bone Minerals and Lean Mass in Children and Adolescents with Motor Disabilities: A Systematic Review and Meta-Analysis

“…This may have been due to the different vibration intensities received by the different body parts. There was evidence in a study that there is an enhanced transmission of floor-based vibration at the distal tibia but a reduction at the distal femur [ 38 ]. Similarly, a previous report demonstrated significantly increased lower-limb lean mass and total body bone mineral content after a 20-week WBVT program using an identical WBVT plate from the same manufacturer of the plate used in the former study ( n = 40) [ 18 ].…”

Skeletal effects of eccentric strengthening exercise: a scoping review

“…This technique uses the bone’s response to low-frequency vibration generated by a mechanical shaker through a probe placed on the participant’s skin [ 32 ]. Since vibration transmission is site-specific and can be attenuated differentially based on body biomechanics or composition [ 63 ], mechanical response tissue analyzer output cannot be compared with the DXA technique. The third method of measurement addressed in this review is quantitative ultrasound used by Chen et al [ 22 ].…”

Vibration therapy in patients with cerebral palsy: a systematic review

“…The definition of vibration exposure varies between single 30 – 33 and repetitive bouts of vibration. 15 , 34 – 37 The duration of the applied vibration varies: 3, 15 10, 37 and 30 seconds 31 , 33 and 1, 32 , 34 , 36 3, 30 and 10 minutes. 35 Details of vibration application can be found in Table 3 .…”

“…The majority of the studies cited (21) were executed in subjects aged 3–17 years. Seven cross-sectional experiments 15 , 30 , 31 , 33 , 35 , 37 , 38 and 14 longitudinal trials 46 , 50 – 60 , 63 , 64 elaborated the efficiency of VT in children, whereas only three 32 , 34 , 36 cross-sectional and four 36 , 47 – 49 longitudinal studies included adult volunteers older than 17 years. In the last few decades, scientific debate in the field of neurorehabilitation has consistently concluded that training regimes commonly achieve higher efficiency in children compared to adolescent patient groups.…”