Design and simulation of polymethyl methacrylate-titanium composite bone fixing plates using finite element analysis: Optimizing the composition to minimize the stress shielding effect

Abstract

Stress shielding is a mechanical phenomenon usually found in load-bearing bone implants. Difference in mechanical properties between the natural bone and the artificial implant leads to stress shielding problem. In the present work, polymethyl methacrylate and commercial pure titanium were selected to design laminate and particulate composites. Optimum composition was theoretically obtained that exhibits mechanical properties close to that of natural human bone. Bone fixing plate was designed for femur bone using computer-aided design. Finite element analysis was adopted to analyze the stress distribution in the bone and implant under static load conditions. Fixing plate with three screws was modeled and simulated using finite element analysis to investigate the stress distribution. Simulation was also done considering 316 L stainless steel as fixing implant and compared with the present optimized composition. Laminate composite with 0.3 volume fraction of titanium has shown mechanical properties close to the bone compared with other combinations. The results have clearly shown that the von-Mises stress induced in the bone with polymethyl methacrylate-titanium laminate composite plates was increased compared with the bone implanted with 316 L steel. Interestingly, laminate composites exhibited higher stresses in the bone compared with particulate composites. From the present design and simulation, it is clearly demonstrated that the laminate composites of polymethyl methacrylate–30% titanium can be an optimum choice for load-bearing implant materials with reduced stress shielding effect.

Keywords

Stress shielding titanium polymethyl methacrylate hydroxyapatite composites femur bone

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References

Park

Lakes

. Biomaterials an introduction, New York: Springer Science and Business Media, 2007, pp. 1–16.

Taylor

Tanner

Freeman

et al.

Stress and strain distribution within the intact femur: compression or bending?

Med Eng Phys 1996; 18: 122–131.

Ridzvan

MIZ

Shuib

Hassan

et al.

Problems of stress shielding and improvement to the hip implant design: a review. J Med Sci 2007; 7: 460–467.

Niinomi

Nakai

. Titanium-based biomaterials for preventing stress shielding between implant devices and bone. Int J Biomater 2011; 2011: Article ID 836587–Article ID 836587.

Wolff

Paul

Ronald

. The law of bone remodelling, New York: Springer, 1986, pp. 1–126.

Chen

Chao

Lidan

et al.

Boning up on Wolff’s Law: mechanical regulation of the cells that make and maintain bone. J Biomech 2010; 43: 108–118.

Frost

. Wolff’s Law and bone’s structural adaptations to mechanical usage: an overview for clinicians. Angle Orthod 1994; 64: 175–188.

Kristina

Gholamreza

. A discussion on plating factors that affect stress shielding using finite element analysis. J Biomech Sci Eng 2010; 5: 129–141.

Schatzker

Horne

Sumnersmith

. Reaction of cortical bone to compression by screw threads. Clin Orthop Relat Res 1975; 111: 263–263.

10.

Perren

Huggler

Russenberger

. Reaction of cortical bone to compression. Acta Orthop Scand 1969; 125: 19–29.

11.

Kristina

Gholamreza

. Prediction of stress shielding around an orthopedic screw: using stress and strain energy density as mechanical stimuli. Comput Biol Med 2013; 43: 1748–1757.

12.

Chung

. Composite materials science and applications, 2nd ed. New York: Springer, 2010, pp. 1–32.

13.

Nikhilesh

Krishna

. Metal matrix composites, 2nd ed. New York: Springer, 2010, pp. 1–36.

14.

Mehboob

Chang

. Effect of structural stiffness of composite bone plate–scaffold assembly on tibial fracture with large fracture gap. Compos Struct 2015; 124: 327–336.

15.

Pouria

Saeid

Vaclav

et al.

Investigating stress shielding spanned by biomimetic polymer-composite vs. metallic hip stem: a computational study using mechano-biochemical model. J Mech Behav Biomed Mater 2015; 41: 56–67.

16.

Kantesh

Vivek

Arvind

et al.

Biosurfaces: a materials science and engineering perspective, New York: Wiley-American Ceramic Society, 2014, pp. 1–60.

17.

Jaeblon

. Polymethylmethacrylate: properties and contemporary uses in orthopaedics. J Am Acad Orthop Surg 2010; 18: 297–305.

18.

Charles

Grabb

Smith

. Grabb and Smith’s plastic surgery, 6th ed. Philadelphia, PA: Wolters Kluwer Health, 2007, pp. 58–67.

19.

Mukhopadhyay

. Mechanics of composite material and structures, Hyderabad, India: Universities Press, 2004, pp. 17–159.