10 - examples - density growth
Transcript of 10 - examples - density growth
110 - examples
10 - examples -
density growth
2example - adaptation in bone
different load cases
Carter & Beaupré [2001]
[1]
[2]
[3]
midstance phase of gait
extreme range of abduction
extreme range of adduction
2317 N
1158 N
1548 N
24˚
-15˚
56˚
703 N
351 N
468 N
28˚
-8 ˚
35˚
3example - adaptation in bone
different load cases
Carter & Beaupré [2001]
combination of all load cases necessary
4example - adaptation in bone
experiment vs simulation
• dense system of compressive trabaculae carrying stress into calcar region
• secondary arcuate system, medial joint surface to lateral metaphyseal region
• ward‘s triangle, low density region contrasting dense cortical shaft
Carter & Beaupré [2001]
5example - adaptation in bone
node point based - h-refinement
6example - adaptation in bone
node point based - p-refinement
7example - adaptation in bone
integration point based - p-refinement
8example - adaptation in bone
parameter sensitivity - instabilities
certain parameters induce checkerboard modesHarrigon & Hamilton [1992],[1994]
9example - adaptation in bone
comparison with x-rays
excellent agreement of simulation and x-ray pattern
Pauwels [1973]
coxa norma coxa valgacoxa vara
10example - hip replacement
total hip replacement vs hip resurfacing
• about 120,000 artificial hip replacements in us per year
• aseptic loosening caused by adaptive bone remodeling
• goal prediction of dredisctribution of bone density
11example - hip replacement
convential total hip replacement
ward‘s triangle • trabeculae • dense cortical shaft
12example - hip replacement
convential total hip replacement
stress shielding • bone resorption • implang loosening
13example - hip replacement
new birmingham hip resurfacing
ward‘s triangle • trabeculae • dense cortical shaft
14example - hip replacement
new birmingham hip resurfacing
improved ingrowth • anatomic situation • less resorption
15example - hip replacement
computer tomography of human femur
patient specific medical treatment
16example - wound healing
wound healing
• epidermal migration / spreading of existing cells
• increase of mitotic activity of about15 times in 1mmwide zone @wound edge
Murray [2003]
17example - wound healing
wound healing
„…thou shouldst bind it with fresh meet the first day,
and thou shouldst treat afterword with grease and
honey every day until he recovers…“ Breadsted [1930]
Edwin Smith Surgical Papyrus [13th Dynasty]
18example - wound healing
tension - single edge notched specimen
19example - wound healing
tension - single edge notched specimen
increased cell activity @wound edge
20example - wound healing
tension - surface cut specimen
increased cell activity @wound edge
21example - wound healing
tension - crack mouth opening displacement
increased cell activity - wound healing & closure
22example - wound healing
bending - single edge notched specimen
increased cell activity @wound edge
23example - wound healing
bending - surface cut specimen
increased cell activity @wound edge
24example - wound healing
bending - crack mouth opening displacement
increased cell activity - wound healing & closure
25example - topology optimization
form follows function
structural design
load case I load case IIoptimal
material distribution I
26example - topology optimization
form follows function
bicycle frames 1817-2005
27example - topology optimization
form follows function
design of bicycle frame
Armstrong [2005] Kuhl [2005]