total hip replacement austin ferro, julie lajoie, michelle medina, maddy ramos

Total Hip Replacement Austin Ferro, Julie Lajoie, Michelle Medina, Maddy Ramos

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

Background Information Artificial Hip Implantation: Surgery lasts 1-2 hours 3-5 days in hospital after surgery 3-6 months for full recovery

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

Problem Statement To create an alternate design for hip replacements incorporating mechanical and material changes to address market gaps in young, active recipients

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

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

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

Decision Matrix Criteria Low WeightToughnessWear rateLifespanMaterial CostLoadabilityBiocompatibility Manufacturabilit y Weight269748105 UHMWPE & Cobalt Chrome **00000000 PMPC & ZTA121 02 40 ZTA on ZTA-2212 0128 ** Datum

Proposed Solution

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

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)

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

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

Testing Design Testing Aspects: -Load testing -Wear debris & mobility testing -Biocompatibility testing

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.

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

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

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

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

Limitations of Proposal Unable to address the following criteria: Longevity of PE with PMPC grafting Fixation testing

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]

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

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 Reduces Production of Wear Particles." Journal of the Mechanical 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.

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 Biocompatibility of." Metallurgical and Materials Transactions A 45.7 (2014): 3110-143. Novel Quaternary Titanium Alloy with near Structure. 01 June 2014. Web. 12 Mar. 2015.

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total hip replacement austin ferro, julie lajoie, michelle medina, maddy ramos

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