title: In vivo bone strain measurements: clinical results, animal experiments, and a proposal for a study of bone demineralization in weightlessness.
abstract: An extensive review of the literature of the aetiology of bone demineralization in weightlessness underline the prevalent effect of mechanical stimulations on bone structure and metabolism. The accurate determination of the mechanical environment of bone can be realized using strain gauges. The results of more than 10 years of clinical application of bone strain measurements demonstrate the interest of this technic. We designed an implantable bone strain transducer composed of a strain gauge embedded in epoxy resin and surrounded by a porous shell. The fixation of the transducer is by bone ingrowth. Results on animals and an acute experimentation on man are presented. The objective of our study in space is to compare the mechanical response of bones of an animal or of a human submitted to normal 1-G gravity and to weightlessness. The average amount of bone strains and their variations during specific movements can be compared.
mesh_terms: D000337:Aerospace Medicine; D000818:Animals; D001696:Biomechanical Phenomena; D001842:Bone and Bones / Q000378:metabolism* / Q000502:physiology; D002118:Calcium / Q000652:urine; D004285:Dogs; D004864:Equipment and Supplies; D006801:Humans; D008903:Minerals / Q000378:metabolism*; D013026:Space Flight; D013314:Stress, Mechanical; D014159:Transducers; D014893:Weightlessness
chemical_list: D008903:Minerals; D002118:Calcium