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Effects of Mechanical Vibration on Bone Tissue
Published in Redha Taiar, Christiano Bittencourt Machado, Xavier Chiementin, Mario Bernardo-Filho, Whole Body Vibrations, 2019
Christiano Bittencourt Machado, Borja Sañudo, Christina Stark, Eckhard Schoenau
Muscles and bones form the basis of human locomotion. Muscles are responsible for the drive and represent the contractile element of movement. Bones represent the stable framework at which the muscles attach in order to fulfil their function. Muscle activity is controlled by the central and peripheral nervous system. It is well recognized that nerves, muscles and bones represent a functional unit. Already more than 100 years ago the anatomist Julius Wolff described the connection between muscles and skeletal development in his “law of the transformation of the bones” (Wolff, 1892; Frost, 1998; Frost, 2004). This law implies that the skeletal system adapts to the forces acting on it, namely the maximal forces. The decisive osteoanabolic stimulus for the osteoblasts is correspondingly the maximum forces acting on bone through the muscles resulting in shear forces. The deformation of the bone is measured by the “mechanostat”, which is formed by the network of osteocytes. In the event of maximal force application to the bone, the synthesis of the bone base substance via the osteoblasts is stimulated by the principle of the “functional muscle-bone unit”. Physical activity accordingly promotes bone formation. On the contrary, with less use, e.g. in the case of long-term immobilization, rapid degradation of bone is induced. This relationship between muscle force and bone development is described in the “functional muscle-bone unit” model and is shown in Figure 10.4.
Biological Responses in Context
Published in Arthur T. Johnson, Biology for Engineers, 2019
Normal bone loading exists in a physiological range of mechanical strain, where the Mechanostat will not activate and therefore will not trigger bone geometric adaptation. Two set-points, an upper strain level and a lower strain level, bound this physiological range and control the type of bone adaptation needed.
An enriched continuum mechanics description of bone tissue to describe mineralization and mechanobiology in bone remodeling
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
M. Martin, P. Pivonka, G. Haïat, V. Sansalone, T. Lemaire
In the past decades, numerous studies have attempted to address the various phenomena that take place simultaneously during bone remodeling. These works are based on Frost’s “mechanostat theory” (Frost 1987) and postulate the existence of a feedback mechanism between mechanical loading and the biochemical activity of bone cells in bone remodeling. Hence, in the wake of this seminal work, multiple phenomenological laws of varying complexity have been developed to describe the evolution of bone porosity (Beaupré et al. 1990; Huiskes et al. 2000), tissue orientation (Huiskes et al. 2000; Doblaré and García 2001), biological and chemical levels (Komarova et al. 2003; Pivonka et al. 2008; Klika et al. 2014) and mineralization (Hernandez et al. 2000; García-Aznar et al. 2005; Rouhi et al. 2007; Ganghoffer et al. 2016).
Cardiorespiratory fitness and arm bone mineral health in young males with spinal cord injury: the mediator role of lean mass
Published in Journal of Sports Sciences, 2019
Irene Rodríguez-Gómez, Soraya Martín-Manjarrés, María Martín-García, Sara Vila-Maldonado, Ángel Gil-Agudo, Luis M. Alegre, Ignacio Ara
Cardiorespiratory fitness (CRF) has been related with bone mass variables, such as bone mineral content (BMC) and BMD (Vicente-Rodriguez et al., 2003). This could be explained because physical activity and muscular development are major determinants of bone mass acquisition (Vicente-Rodriguez, Ara, Pérez-Gómez, Dorado, & Calbet, 2005) and this important osteogenic effect is partially mediated through the lean mass (LM). Furthermore, higher LM could generate higher bone tensions (Heinonen, Sievänen, Kannus, Oja, & Vuori, 2002). For these reasons, LM is an excellent indicator of bone mechanical stimulation and its changes are highly correlated with bone health (Vicente-Rodriguez et al., 2005; Wetzsteon et al., 2011). This could be partly explained by the mechanostat theory, which states that bone strength is regulated by modelling and remodelling processes depending on the forces acting on the bones (Schoenau & Frost, 2002). Although LM is considered the best predictor of BMC (El Hage, Courteix, Benhamou, Jacob, & Jaffré, 2009; Zhu et al., 2014), its relationship with bone health is complex due to the multiple associations in which this body composition component is involved. Moreover, no studies have jointly examined the association of these predictors with bone outcomes in SCI patients and specifically through mediation analysis. This analysis is a statistical procedure that can be used to clarify the process underlying the relationship between two variables and the extent to which this relationship can be modified, mediated or confounded by a third variable (Baron & Kenny, 1986). Therefore, it would be of interest to assess whether an optimal CRF could influence bone health through the presence of greater LM in these specific patients and above all, whether a specific adaptation in the arms is present in this population given that their upper extremities are essential for them to carry out activities of daily living.
The influence of musculoskeletal forces on the growth of the prenatal cortex in the ilium: a finite element study
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Peter J. Watson, Michael J. Fagan, Catherine A. Dobson
The remodelling of bone is believed to follow the ‘mechanostat’ model of bone regulation (Frost 2003), whereby bone is either formed or resorbed in response to the mechanical strains that it experiences. Based on this theory, it has been suggested that the internal architecture of the pelvis remodels in order to align with the principal strain trajectories associated with bi-pedal locomotion (Macchiarelli et al. 1999; Rook et al. 1999).