Rohlmann Antonius, Schmidt Hendrik, Gast Ulf, Kutzner Ines, Damm Philipp, Bergmann Georg
Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany,
Eur Spine J. 2014 Mar;23(3):666-72. doi: 10.1007/s00586-013-3087-8. Epub 2013 Nov 8.
It is assumed that whole body vibration (WBV) improves muscle strength, bone density, blood flow and mobility and is therefore used in wide ranges such as to improve fitness and prevent osteoporosis and back pain. It is expected that WBV produces large forces on the spine, which poses a potential risk factor for the health of the spine. Therefore, the aim of the study was to measure the effect of various vibration frequencies, amplitudes, device types and body positions on the loads acting on a lumbar vertebral body replacement (VBR).
Three patients suffering from a fractured lumbar vertebral body were treated using a telemeterized VBR. The implant loads were measured during WBV while the patients stood on devices with vertically and seesaw-induced vibration. Frequencies between 5 and 50 Hz and amplitudes of 1, 2 and 4 mm were tested. The patients stood with their knees straight, slightly bent, or bent at 60°. In addition, they stood on their forefeet.
The peak resultant forces on the implant increased due to vibration by an average of 24% relative to the forces induced without vibration. The average increase of the peak implant force was 27% for vertically induced vibration and 15% for seesaw vibration. The forces were higher when the legs were straight than when the knees were bent. Both the vibration frequency and the amplitude had only a minor effect on the measured forces.
The force increase due to WBV is caused by an activation of the trunk muscles and by the acceleration forces. The forces produced during WBV are usually lower than those produced during walking. Therefore, the absolute magnitude of the forces produced during WBV should not be harmful, even for people with osteoporosis.
全身振动（WBV）被认为可提高肌肉力量、骨密度、血流量及活动能力，因此被广泛应用于改善健康状况、预防骨质疏松症和背痛等领域。预计WBV会在脊柱上产生较大作用力，这对脊柱健康构成潜在风险因素。因此，本研究的目的是测量不同振动频率、振幅、设备类型和身体姿势对腰椎椎体置换物（VBR）上所受负荷的影响。
对三名腰椎椎体骨折患者采用遥测式VBR进行治疗。在患者站在垂直振动和跷跷板式振动设备上进行WBV时，测量植入物负荷。测试了5至50赫兹的频率以及1、2和4毫米的振幅。患者站立时膝盖伸直、微屈或弯曲60°。此外，他们还踮着脚站立。
相对于无振动时产生的力，振动使植入物上的合成峰值力平均增加了24%。垂直振动时植入物峰值力的平均增加幅度为27%，跷跷板振动时为15%。腿部伸直时的力高于膝盖弯曲时的力。振动频率和振幅对测量到的力影响较小。
WBV导致的力增加是由躯干肌肉的激活和加速力引起的。WBV期间产生的力通常低于行走时产生的力。因此，即使对于骨质疏松症患者，WBV期间产生的力的绝对值也不应有害。
