Total Hip Replacement Austin Ferro, Julie Lajoie, Michelle
Medina, Maddy Ramos
Slide 2
Background Information Total Hip Replacement (THR) A surgical
procedure in which diseased cartilage and bone of hip joint is
replaced with artificial materials Used to treat osteo
degeneration, fractures 2.5 million people in the United States
have had a total hip replacement surgery
Slide 3
Background Information Artificial Hip Implantation: Surgery
lasts 1-2 hours 3-5 days in hospital after surgery 3-6 months for
full recovery
Slide 4
Current Problems Mechanical wear -Prominent in metal on metal
designs -Leads to particulate debris and osteolysis -Limited
bearing surface lifespan Resection -Large volume of healthy,
natural bone removed Stress Shielding -Large differences in elastic
moduli of bone and implant material results in bone
degradation
Slide 5
Problem Statement To create an alternate design for hip
replacements incorporating mechanical and material changes to
address market gaps in young, active recipients
Slide 6
Material Criteria All criteria in reference to the standard hip
implant: (Cobalt- Chromium on CLPE) Wear rate less than 0.6 m/year
Lifespan greater than 20 years Elastic modulus of bone interface
material close to 17.4 GPa
Slide 7
Testing Design Criteria Wear testing performed for all
directions of natural motion (adduction & abduction, flexion
& extension, circumduction) Minimum of one million cycles on
wear testing machine Implant fixated at 22 for load bearing
capacity testing Circumduction
Slide 8
Materials Considered Bearing surfaces: Ti-6Al-4V on Ultra high
molecular weight polyethylene (UHMWPE) Zirconia Toughened Alumina
Ceramic (ZTA) on ZTA ZTA on UHMWPE with Poly(2-methacryloyloxyethyl
phosphorylcholine) (PMPC) Graft
Slide 9
Decision Matrix Criteria Low WeightToughnessWear
rateLifespanMaterial CostLoadabilityBiocompatibility
Manufacturabilit y Weight269748105 UHMWPE & Cobalt Chrome
**00000000 PMPC & ZTA121 02 40 ZTA on ZTA-2212 0128 **
Datum
Slide 10
Proposed Solution
Slide 11
Mechanical Design Combination of multiple successful designs o
Birmingham Mid Head Resection (BMHR) o Metha Short Hip Preserve
femoral neck o Load distribution proximal loading Rectangular
cross-section Less invasive revision
Slide 12
Acetabular Cup and Stem Material Titanium alloy
(Ti-20Nb-10Zr-5Ta) Biocompatible (low toxicity, corrosion) High
hardness value and UTS E closer to human bone than Ti Titanium
plasma-spray surface (TPS)
Slide 13
Acetabular Lining Material Cross-linked UHMWPE With a PMPC
graft mechanical integrity, biocompatibility Cross linking
increases wear resistance, wear rate between bearing surfaces 0.2
m/year PMPC graft significantly suppressed wear in liner
Slide 14
Femoral Head Material Zirconia toughened Alumina Ceramic (ZTA)
Biolox Delta Ceramic o Alumina (75%) Biocompatibility o Zirconia
(25%) Mechanical properties Increased toughness Crack resistance
Reduced wear debris
Load testing Fixture -Instron 1122 Material Testing Machine
-Femur cemented at 22 degrees -Load testing will be performed by
testing our -4 strain gauges -(1) 45 degree stacked proximal medial
-(3) axial strain gauges proximal lateral, distal medial, and
distal lateral. Data Collection -Device implanted in six femurs
-Comparing microstrain to a Native femur through an ANOVA repeated
measures test. -Gauge locations for Native femur comparison data
has already been recorded by Dr. Hazelwood.
Slide 17
Wear Debris and Mobility Testing AMTI Bragdon CR & Harris
HW - 12 stations - 3 axes - Anatomical position head - Up to 4500 N
loading - Flexion-Extension ( 25) - Abduction-Adduction ( 9) -
Internal-External Rotation ( 20) - Wear Rate = 4.8 1.1 mg/Mc
Slide 18
Biocompatibility Testing UHMWPE With a PMPC graft [3] water
contact angle of UHMWPE decreased from 80 to 15 after grafting PMPC
for 45 min wear rate of modified samples decreased blood
compatibility increased significantly
Slide 19
Relevant ISO Docs ISO 10993 histology bench testing ISO 7206-2
standard spec. for THR bearing surfaces of metallic, ceramic,
polymeric material ISO 14242-2 periods of 500,000 cycles
Slide 20
Cost Fixed 510K : $6,100 Testing Mechanical testing -Femurs:
$1,200 -Instron 1122 Material Testing Machine: Free on Cal Poly
Campus -Strain gauges: Free on Cal Poly Campus -Contact angle
measurement system: Free on Cal Poly Campus Biocompatibility
testing -Sheep: $3,000 -Equipment: $10,000 Variable Manufacturing:
$800 - $1300 Materials: $200 Unknown Quality control Salaries Total
Estimated Product Cost: $3,000
Slide 21
Limitations of Proposal Unable to address the following
criteria: Longevity of PE with PMPC grafting Fixation testing
Slide 22
Future Considerations In Vivo Testing Clinical Trials FDA
Approval Class Level II 510 K Pathways CDRH learn video and
feedback Review and registration Possible Adaptations Implementing
a blending of Vitamin-E with UHMWPE for hip prostheses prevent
oxidative degradation VE containing debris may elicit a reduced
bio. response [2]
Slide 23
Summary Over 30,000 revision hip replacement surgeries are
performed in the United States every year [13] Path to Market 510K
Total Pre-fabrication cost: $23,000 Total Product costs $1,500
Industry GapsOur Design Changes Wear debrisMaterials Bone resection
volumeSmaller stem Stress ShieldingNovel Titanium Alloy for stem
and acetabular cup
Slide 24
References [1] ASTM F2033-12, Standard Specification for Total
Hip Joint Prosthesis and Hip Endoprosthesis Bearing Surfaces Made
of Metallic, Ceramic, and Polymeric Materials, ASTM International,
West Conshohocken, PA, 2012, www.astm.orgwww.astm.org [2] Uetsuki,
K Sugimoto, T Turner, A C Tomita, N. Controversial effects of
blending Vitamin-E with UHMWPE on the wear resistance of Hip and
Knee prostheses R&D Center, Nakashima Medical Co. Ltd., Kyoto
Japan, 2012 [3] Dangsheng X. and Yaling Deng, Nan Wang, Yuanyuan
Yang. Influence of surface PMPC brushes on tribological and
biocompatibility properties of UHMWPE Elsvier 5661, Science Direct
2014. [4] Moro, Toru, Hiroshi Kawaguchi, Kazuhiko Ishihara,
Masayuki Kyomoto, Tatsuro Karita, Hideya Ito, Kozo Nakamura, and
Yoshio Takatori. "Wear Resistance of Artificial Hip Joints with
Poly(2-methacryloyloxyethyl Phosphorylcholine) Grafted
Polyethylene: Comparisons with the Effect of Polyethylene
Cross-linking and Ceramic Femoral Heads." Biomaterials 30.16
(2009): 2995-3001. Web. [5] Moro, Toru, Masayuki Kyomoto, Kazuhiko
Ishihara, Kenichi Saiga, Masami Hashimoto, Sakae Tanaka, Hideya
Ito, Takeyuki Tanaka, Hirofumi Oshima, Hiroshi Kawaguchi, and
Yoshio Takatori. "Grafting of Poly(2-methacryloyloxyethyl
Phosphorylcholine) on Polyethylene Liner in Artificial Hip Joints
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Behavior of Biomedical Materials 31 (2014): 100-06. Web. [6] Davis,
Jennifer. "Adding up How Many Americans Are Living With Hip and
Knee Implants." Arthritis Foundation. N.p., 28 Mar. 2014. Web. [7]
"Questions and Answers About Hip Replacement." Questions and
Answers about. N.p., n.d. Web. 12 Mar. 2015.
Slide 25
References [8] Mckellop, H., I. Clarke, K. Markolf, and H.
Amstutz. "Friction and Wear Properties of Polymer, Metal, and
Ceramic Prosthetic Joint Materials Evaluated on a Multichannel
Screening Device." Journal of Biomedical Materials Research 15.5
(1981): 619-53. Web. [9] Bergmann, G., F. Grachien, A. Rohlmann, A.
Bender, B. Heinlein, GN Duda, MO Heller, and MM Morlock. "Realistic
Loads for Testing Hip Implants." Biomedical Materials Engineering
(2010): 66-75. Pub Med. Web. [10] Callaghan, John J., and Steve S.
Liu. "CERAMIC ON CROSSLINKED POLYETHYLENE IN TOTAL HIP REPLACEMENT:
ANY BETTER THAN METAL ON CROSSLINKED POLYETHYLENE." Iowa Orthopedic
Journal (2009): 1-4. Pub Med. Web. [11] Disegi, John. "Ceramic
Implant Materials." Composites 23.5 (1992): 380. Nov. 2008. Web.
[12] Furmanski, Jevan, Martin Anderson, Sonny Bal, A. Seth
Greenwald, David Halley, Brad Penenberg, Michael Ries, and Lisa
Pruitt. "Clinical Fracture of Cross-linked UHMWPE Acetabular
Liners." Biomaterials 30.29 (2009): 5572-582. Web. [13] Hip
Revision Surgery. AAOS Patient Education. smith&nephew. Wed.
[14] Popa, Monica, Ecaterina Vasilescu, Paula Drob, Doina Raducanu,
Jose Maria Calderon Moreno, Steliana Ivanescu, Cora Vasilescu, and
Silviu Iulian Drob. "Microstructure, Mechanical, and Anticorrosive
Properties of a New Ti-20Nb-10Zr-5Ta Alloy Based on Nontoxic and
Nonallergenic Elements." Metals and Materials International 18.4
(2012): 639-45. Web. [15] Popa, Monica, Ecaterina Vasilescu, Paula
Drob, Doina Raducanu, Jose Maria Calderon Moreno, Steliana
Ivanescu, Cora Vasilescu, Silviu Iulian Drob, and Ingrid Milosev
[16] "Structural Analysis, Electrochemical Behavior, and
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45.7 (2014): 3110-143. Novel Quaternary Titanium Alloy with near
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