Simulation of Osteoporotic Bone Remodeling - Computational Biomechanics of the Musculoskeletal System - page 341

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Tibia cortical bone
Femur cortical bone

50

40

30

20

10

0 0

10 20

Time post-injury (year)

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FIgure 25.5 Changes of mechanical load for both models.

Biological factors such as aging, menopause, and drug treatment can modulate the system by
changing the thresholds or changing the intensities of certain signals (Li et al., 2001). In the bone
remodeling system, the contributions of mechanical factors and biological factors are coupled.
Consideration for changes in the mechanical environment, in biological factors, and in particular
their coupling relationships may offer a deeper understanding of osteoporosis. Because of the discrep-
ancies in different individuals, this simulation method can be used to predict bone loss patterns for each
individual according to his or her personal characteristics, for example mechanical environment and
biological conditions, such as the level of physical activity, gender, age, hormone levels, and so on. In
addition, if the change of bone mass could be obtained, and changes in one of the biological or mechan-
ical factors were known, the simulation method developed may also be used to predict the changing
patterns of the other. For example, age-related bone loss can be simulated when the age-related muscle
strength is available (e.g., Brooks and Faulkner, 1994). The effects of mechanical loading can also be
simulated given the bone loss patterns (Gong et al., 2006). These parameters are important for evaluat-
ing the biological and mechanical status of bone, and may help to provide more insight into the mecha-
nism of osteoporosis and identify improved osteoporosis treatment and prevention.

aCknowledgmentS
This work is supported by a grant from the National Natural Science Foundation of China (No.
11120101001, 11322223, 11272273) and the Program for New Century Excellent Talents in University
(NCET-12-0024).

reFerenCeS
Baron, R., Tross, R., and A. Vignery. 1984. Evidence of sequential remodeling in rat trabecular bone: morphol-
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Beaupré, G. S., Orr, T. E., and D. R. Carter. 1990. An approach for time-dependent bone modeling and remodeling—
application: a preliminary remodeling simulation. J Orthop Res 8:662-70.
Brooks, S. V., and J. A. Faulkner. 1994. Skeletal muscle weakness in old age: underlying mechanisms. Medical
Science of Sports and Exercise 26:432-39.
Currey, J. D. 1988. The effect of porosity and mineral content on the Young's modulus of elasticity of compact
bone. J Biomech 21:131-39.