Biomechanics

Mechanics is the science of motion and force. Biomechanics is the human equivalent of this concept. It is the study of the mechanical operation of the human body, or the science of motion and force in living organisms. In biomechanics, the function of the body components is monitored and job requirements are modified to lower internal and external stresses. The musculoskeletal system provides the foundation data for the study of biomechanics. As in anthropometries, there are two types of biomechanical measurements  

Statics the study of bodies remaining at rest (equilibrium) as a result of forces acting upon them 

Load the external forces upon a structure or organism 

Stresses the internal forces generated in the structure as a result of loading 

In human bodies, all movement is possible due to the application of load and stress to biological levers. The field of biomechanics, which teaches about joints, bones, and muscles, provides safety professionals with an understanding of how the musculoskeletal levers of the body are designed to work. This awareness can be applied to identify and eliminate unnatural movements resulting in ergonomic problems. Evaluation activities such as monitoring frequency and duration of 

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A significant aspect of hip joint biomechanics is that the stmctural components are not normally subjected to constant loads. Rather, this joint is subject to unique compressive, torsion, tensile, and shear stress, sometimes simultaneously. Maximum loading occurs when the heel strikes down and the toe pushes off in walking. When an implant is in place its abiUty to withstand this repetitive loading is called its fatigue strength. If an implant is placed properly, its load is shared in an anatomically correct fashion with the bone. 

Biomechanical Machines. The mechanical properties of fibrous polypeptides could be put to use for the commercial production of fibers (qv) that are more elastic and resiUent than available synthetics (see Silk). The biochemical properties of proteins could also be harnessed for the conversion of mechanical energy to chemical energy (35). 

Faria, I., and Cavanaugh, P. (1978). The Physiology and Biomechanics ol Cycling. New York Wiley. 

Penner, D. E., Lehrer, R., Schauble, L. (1998). From physical models to biomechanics A design based modeling approach. The Journal of the Learning Sciences, 7, 429 149. 

One of the major concerns for law-enforcement agencies in using less-lethal ammunition projectiles is the delicate balance between their effectiveness and their lethality. Impact biomechanics studies of a human body, including the use of less-lethal projectiles, are critically important when considering the protection of military personnel and civilians from accidental injury. 

Bir et al." have analyzed the effect of blunt ballistic impact of a baton-type, less-lethal projectile on the thoracic region using human cadavers. She determined human-response corridors and developed biomechanical surrogates, which can be used for testing different new projectiles for their blunt ballistic impact. The human-response force corridor for blunt thoracic impact by a thermoplastic polyurethane-based baton round with 37 mm diameter, weighing 30 g, and traveling... 

Atkinson, P.J., Ewers, B.J., and Haut, R.C. Blunt injuries to the pateUofemoral joint resulting from transarticular loading are influenced by impactor energy and mass, J. Biomech. Eng., 123, 293, 2001. Cooper, G.J. et al. The biomechanical response of the thorax to nonpenetrating impact with particular... 

Viano, D.C. et al. Ballistic impact to the forehead, zygoma, and mandible Comparison of human and frangible dummy face biomechanics, J. Trauma, 56, 1305, 2004. 

Bir, C., Viano, D., and King, A. Development of biomechanical response corridors of the thorax to blunt ballistic impacts, J. Biomech., 37, 73, 2004. 

Shewry, P.R., Tatham, A.S., and Bailey, A.J. (Eds.), Elastomeric Proteins Structures, Biomechanical Properties and Biological Roles, Cambridge University Press, Cambridge, 2002. 

Burrows, M., Biomechanics Froghopper insects leap to new heights. Nature, 424, 509, 2003. 

Figures 4 and 5 give a broad indication of the relevant biomechanical properties of a number of flow sensitive biomaterials. In the case of the data shown in Fig. 5, the surface mechanical properties are lumped into a single measure of the surface integrity. Admittedly, in view of what has been said in the introduction about the viscoelastic nature of the wall material, the information given in Figs. 4 and 5 are oversimplistic. The data in Fig. 5 are based on reported critical minimum stresses (often expressed in terms of the mean bulk fluid stresses) at which physical damage is first observed. Figure 6 gives an indication of the...

Andersen SO (2003) In Shewry PR, Tatham AS, Bailey AJ (eds) Elastomeric proteins structures, biomechanical properties, and biological roles. Cambridge University Press, Cambridge, pp 259-278... 

OA develops when systemic factors and biomechanical vulnerabilities combine. Systemic factors include age, gender, genetic predisposition, and nutritional status. Age is the strongest predictor of OA, although advanced age alone is insufficient to cause OA. 

Stress lifestyle modifications for rehabilitation and prevention. Recommend strength training, range-of-motion exercises, and a warm-up period before exercise. In repetitive-motion injury, recommend methods to correct biomechanical abnormalities and vary work tasks as applicable. Refer to a physical therapist or sports trainer as needed. 

Giraud-Guille, M.M., Besseau, L. and Martin, R. (2003) Liquid crystalline assemblies of collagen in hone and in vitro systems. Journal of Biomechanics, 36, 1571-1579. 

Currey, J.D. (1998) The effect of porosity and mineral-content on the Youngs modulus of elasticity of compact-bone. Journal of Biomechanics, 21, 131-139. 

In the normal healthy IVD, the cells not only produce matrix macromolecules and growth factors, they also produce a myriad of proteases [26, 27]. Included in this list of proteases are the matrix metalloproteinases (MMPs) and aggrecanolytic members of the disintegrin and metalloproteinase with thrombospondin motif family (ADAMTS) as well as their respective inhibitors. It is the maintenance of this critical balance that results in a healthy IVD ECM that is subsequently well adapted for its physiologic and biomechanical function. 

Bastian L et al (2001) Evaluation of the mobility of adjacent segments after posterior thoracolumbar fixation a biomechanical study. Eur Spine J 10(4) 295-300... 

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