Cross-sectional properties along the diaphysis of the rat femur as influenced by forced running exercise.

Postcranial robusticity in Homo. II: Humeral bilateral asymmetry and bone plasticity

“…This research began with efforts to document, both macroscopically and histologically, the nature of changes in diaphyseal bone in contrasting mechanical environments, using mechanical devices, partial paralysis, surgical osteotomies, and exercise regimes (e.g., Rutishauser and Majno, 1949;Riesenfeld, 1966;Tschantz and Rutishauser, 1967;Saville and Whyte, 1969;Liskova and Hert, 1971;Chamay and Tschantz, 1972;Amtmann and Oyama, 1973). This work has been followed (e.g., Goodship et al, 1979;Woo et al, 1981;Lanyon et al, 1982;Lanyon, 1982;Matsumura and Okada, 1987;Burr et al, 1989;Turner et al, 1991) by experiments in which the nature of the response has been increasingly documented, assessing the degrees of subperiosteal vs. endosteal deposition and resorption, the effects of age of the individual on remodeling patterns, and the resultant consequences on the strength of the diaphysis after recovery (in cases of surgical intervention) or at the end of the exercise regime. In general, these studies have demonstrated that bone will atrophy or experience hypotrophy (in cases of developmental changes) under conditions of either constant (static) or reduced mechanical stress (and associated strain) levels and will hypertrophy under conditions of elevated, but physiologically intermittent, mechanical stress (and strain), provided that failure of the system does not occur.…”

Robusticity versus Shape: The Functional Interpretation of Neandertal Appendicular Morphology.

“…There is little question that all appendicular skeletal morphology, in conjunction with its surrounding soft tissue, has a geneticallydetermined developmental baseline. However, it has also been documented through clinical cases, experimental work with non-human mammals, and post-traumatic remodeling in fossil remains (e.g., ARKIN and KATZ, 1956;RIESENFELD, 1966;HOUSTON and ZALESKI, 1967;TSCHANTZ and RUTISHAUSER, 1967;LISKOVA and HERT, 1971;GOODSHIP et al, 1979;LANYON, 1980LANYON, , 1982LANYON et al, 1982;MATSUMURA and OKADA, 1987; that there is considerable plasticity in the development of most aspects of appendicular skeletal morphology. This applies in particular to diaphyseal shape and size and to articular orientations, since levels and patterns of biomechanical stress can alter levels and patterns of subperiosteal and endosteal deposition/resorption and of metaphyseal apposition.…”

Bending strength of the rat femur as influenced by running exercise and diet program.

“…It has been shown that both bone density and strength responded to exercise and muscle activity in animals (SMITH and SAVILLE, 1966;AMT-MANN, 1979;MALINA, 1979). On the other hand, it is well known that the restriction of calcium intake exerts a negative influence on bone strength and density (GALFSKY et al, 1975;EZAWA et al, 1979 The present authors previously reported the effects of nutritive condition and enforced running exercise on musculo-skeletal growth in rats (MATSUMURA, 1982) and cross-sectional properties of the femur shaft (MATSUMURA et al, 1983;MATSUMURA and OKADA, 1987). The purpose of this paper is to examine the effect of nutritive conditions and exercise factors on the strength and density of the rat femur.…”

“…On the other hand, the authors previously found in the proximal half of the rat femur shaft that the cross-section was elongated due to the influence of running exercise increasing the area moment of inertia in the direction of maximum principal axis which is close to medio-lateral direction (MATSUMURA, et al, 1983, MATSUMURA andOKADA, 1987).…”