10 - examples - density growth

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1 10 - examples 10 - examples - density growth 2 example - 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˚ 3 example - adaptation in bone different load cases Carter & Beaupré [2001] combination of all load cases necessary 4 example - 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]

Transcript of 10 - examples - density growth

Page 1: 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]

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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]

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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

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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]

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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

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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

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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]