Biomedical Engineering Reference
In-Depth Information
of the long-term behavior of the bone under loading, but also in its rate of adaptation
and the specific role of bone cells at each stage of the mechanosensation and
adaptation processes. In this direction, some attempts have been made toward its
modeling [18-20, 51-55].
In this sense, a first mechanistic model of bone remodeling is the one proposed by
Huiskes
et al
. [51]. In this mathematical model, they proposed that bone resorption
(by osteoclasts) and bone formation (by osteoblasts) coupled activity is exclusively
regulated by mechanical factors. In fact, they considered the strain energy density
rate as the regulator mechanical stimulus while the osteocytes' spatial distribution
defines the mechanosensor system attenuated by the distance. The osteoclast
activation is considered to be regulated by disuse and microdamage, while bone
formation is activated when the mechanical stimulus at a surface location exceeds
a threshold value.
Load history
Material properties
Bone geometry
Daily strain
stimulus
x
Genetic, hormonal
and metabolic factors
Mechanical
damage
Damage
growth
d
>
0
Transducer
Bone
remodeling
Inhibitory signal
s
BMU
Activity
d
<
0
Σ
Damage
repair
Osteoclast
activity
Osteoblast
activity
Mineralization
activity
Σ
Bone volume
fraction (v
b
)
Damage (d)
Mineralization (
a
)
Figure 4.1
Scheme of the bone remodeling theory described in Garcıa-Aznar
et al
. [20].
