Prosthetics/orthotics/devicesA 3-dimensional finite element model of the human foot and ankle for insole design
Section snippets
Methods
The geometry of the finite element model was obtained from 3-D reconstruction of magnetic resonance (MR) images from the right foot of a healthy man in his mid twenties (height, 174cm; weight, 70kg). Coronal MR images were taken at intervals of 2mm in the neutral unloaded position. The images were segmented using MIMICS, version 7.10,a to obtain the boundaries of skeleton and skin surface. The boundary surfaces of the skeletal and skin components were processed using SolidWorks 2001b to form
Results
We constructed a 3-D finite element model of the human foot and ankle to study the effects that stiffness and shape of foot insole have on plantar pressure distribution, and to study the internal stresses in the bones during balanced standing. Figure 2 depicts the plantar pressure distribution obtained from the F-scan measurements and figure 3 gives the pressure distribution predicted by finite element simulation during balanced standing. Both the measured and predicted values showed high
Discussion
The predicted plantar pressure distribution pattern was, in general, comparable to the F-scan measurement. However, the predicted values of peak pressure were higher than the F-scan measurements. The difference may be caused by resolution differences between the F-scan measurement and the finite element analysis. Having a spatial resolution of about 4 sensors per cm2, the F-scan sensors recorded an average pressure for an area of 25mm2. By contrast, the finite element analysis provided
Conclusions
A geometric, detailed 3-D finite element model of the human foot and ankle was developed to estimate the plantar pressure and the internal stress and strain in the bony and soft tissue structures under various loading and supporting conditions. Finite element analysis indicated that the insole’s custom-molded shape is more important in reducing peak plantar pressure than the stiffness of the material from which it is made. A comprehensive, finite element, ankle-foot model makes monitoring the
Acknowledgment
We thank the Scanning Department of St. Teresa’s Hospital, Kowloon, Hong Kong, for facilitating the MR scanning.
References (25)
- et al.
Orthotic management of plantar pressure and pain in rheumatoid arthritis
Clin Biomech (Bristol, Avon)
(1999) - et al.
The reduction and redistribution of plantar pressures using foot orthoses in diabetic patients
Diabetes Res Clin Pract
(1996) - et al.
Effect of customized insoles on vertical plantar pressures in sites of previous neuropathic ulceration in the diabetic foot
Foot
(2000) - et al.
A study of in-shoe plantar shear in normals
Clin Biomech (Bristol, Avon)
(2000) Plantar soft tissue loading under the medial metatarsals in the standing diabetic foot
Med Eng Phys
(2003)- et al.
The effect of insoles in therapeutic footweara finite-element approach
J Biomech
(1997) - et al.
Biomechanical assessment of plantar foot tissue in diabetic patients using an ultrasound indentation system
Ultrasound Med Biol
(2000) - et al.
In vitro method for quantifying the effectiveness of the longitudinal arch support mechanism of a foot orthosis
Clin Biomech (Bristol, Avon)
(1995) - et al.
Prevalence of foot pathology and lower extremity complications in a diabetic outpatient clinic
J Rehabil Res Dev
(1989) - et al.
Reduction of plantar pressure with the rigid relief orthosis
J Am Podiatr Med Assoc
(1993)
Pressure distribution under symptom-free feet during barefoot standing
Foot Ankle
Effects of total contact insoles on the plantar stress redistributiona finite element analysis
Clin Biomech (Bristol, Avon)
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Supported by the Hong Kong Jockey Club (endowment) and The Hong Kong Polytechnic University (research studentship and research grant G-T888).
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.