Such pharmacologic treatments are now commonly used on children (sometime extremely young) during long periods (2–5 years) with the rationale to maximize the impact on a growing skeleton. However, some concerns have been raised about the equivocal efficiency on the fracture reduction [4] and [5], the accumulation of those long life drugs
and the impact of inhibiting bone remodelling over long periods, which results in the build-up of poor quality, highly mineralized bone [1] and [6]. GDC-0199 mouse It is recognized that the bone tissue is highly responsive to dynamic loading and is able to adapt its architecture and mass to the mechanical loading environment [7], [8] and [9]. Bone remodelling is sensitive to strain magnitude [10] and [11], frequency [12] and [13], number of loading cycles [14], strain rate [15] and rest periods between stimulation [16]. In addition to bone response to high peak strains [17] and [18], there is also evidence of bone adaptation at low strain but high frequency loading [9] and [19]. Because high strain exercises in patient suffering from OI may result in fracture, high frequency low amplitude whole body mechanical
vibration (WBV) is an attractive low-impact and drug-free approach to stimulate bone formation. The therapeutic impact of Stem Cell Compound Library WBV treatment has been observed on muscle strength, motion, posture and bone density in various osteopenic populations: young women [20] and [21], post-menopausal women [22], [23], [24] and [25] or children with disabling conditions like cerebral palsy [26] or with OI [27] but no effect has been observed on healthy adults [28]. However more investigations are required to confirm the impact of WBV on
bone mass and to identify the most efficient vibration parameters and the most responsive target population [29], [30], [31], [32] and [33]. Numerous studies have investigated the influence of WBV on bone formation using a large variety of animal models (sheep, rat, mouse) [34], [35], [36] and [37], age (growing, young or old adults) [38], [39] and [40], L-gulonolactone oxidase vibration frequency (from 20 to 90 Hz) [41], [42] and [43], maximum peak acceleration (from 0.1 to 3 g) [43] and [44], treatment duration (from 10 to 30 min) and treatment length (from 2 weeks to 1 year). A significant osteogenic effect was observed in the trabecular bone of both the femoral condyle and tibial metaphysis of adult sheep (1 year treatment, 30 Hz, 0.3 g) [35] and [36]. In adult mice, an osteogenic response to WBV is observed in the tibial metaphysis with a non-dose dependent response to acceleration (5 weeks treatment, 45 Hz, 0.1, 0.3 and 1 g) [44]. An influence of the mouse genotype was observed: the osteogenic response to WBV inversely correlated to the low (C57Bl/6J), medium (BALB/c) or high (C3H) bone density of the mouse strain (2 to 3 weeks treatment, 45 Hz, 0.25 g) [37].