Bone Adaptation in Response to Different Load Cases: A Comprehensive Study

1. 10 - examples - density growth 10 - examples

2. different load cases [1] midstance phase of gait 2317 N 24˚ 703 N 28˚ [2] extreme range of abduction 1158 N -15˚ 351 N -8 ˚ [3] extreme range of adduction 1548 N 56˚ 468 N 35˚ Carter & Beaupré [2001] example - adaptation in bone

3. different load cases combination of all load cases necessary Carter & Beaupré [2001] example - adaptation in bone

4. 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] example - adaptation in bone

5. node point based - h-refinement example - adaptation in bone

6. node point based - p-refinement example - adaptation in bone

7. integration point based - p-refinement example - adaptation in bone

8. parameter sensitivity - instabilities certain parameters induce checkerboard modes Harrigon & Hamilton [1992],[1994] example - adaptation in bone

9. comparison with x-rays Pauwels [1973] coxa vara coxa norma coxa valga excellent agreement of simulation and x-ray pattern example - adaptation in bone

10. 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 example - hip replacement

11. convential total hip replacement ward‘s triangle • trabeculae • dense cortical shaft example - hip replacement

12. convential total hip replacement stress shielding • bone resorption • implang loosening example - hip replacement

13. new birmingham hip resurfacing ward‘s triangle • trabeculae • dense cortical shaft example - hip replacement

14. new birmingham hip resurfacing improved ingrowth • anatomic situation • less resorption example - hip replacement

15. computer tomography of human femur patient specific medical treatment example - hip replacement

16. wound healing Murray [2003] • epidermal migration / spreading of existing cells • increase of mitotic activity of about15 times in 1mm wide zone @wound edge example - wound healing

17. wound healing Edwin Smith Surgical Papyrus [13th Dynasty] „…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] example - wound healing

18. tension - single edge notched specimen example - wound healing

19. tension - single edge notched specimen increased cell activity @wound edge example - wound healing

20. tension - surface cut specimen increased cell activity @wound edge example - wound healing

21. tension - crack mouth opening displacement increased cell activity - wound healing & closure example - wound healing

22. bending - single edge notched specimen increased cell activity @wound edge example - wound healing

23. bending - surface cut specimen increased cell activity @wound edge example - wound healing

24. bending - crack mouth opening displacement increased cell activity - wound healing & closure example - wound healing

25. form follows function optimal material distribution I load case I load case II structural design example - topology optimization

26. form follows function bicycle frames 1817-2005 example - topology optimization

27. form follows function Armstrong [2005] Kuhl [2005] design of bicycle frame example - topology optimization