A paradigm for the development and evaluation of novel implant topologies for bone fixation: In vivo evaluation

JOURNAL OF BIOMECHANICS

卷:45

Article

Long, Jason P.¹  Hollister, Scott J.^2,3,4  Goldstein, Steven A.^1,2,3 

[1] Univ Michigan, Dept Orthopaed Surg, Ann Arbor, MI 48109 USA

[2] Univ Michigan, Dept Biomed Engn, Ann Arbor, MI 48109 USA

[3] Univ Michigan, Dept Mech Engn, Ann Arbor, MI 48109 USA

[4] Univ Michigan, Dept Surg, Ann Arbor, MI 48109 USA

关键词: Orthopedic implant design;    Osseointegration;    Bone;    Mechanical stimulation;   

DOI  :  10.1016/j.jbiomech.2012.08.011

来源: Elsevier

【 摘 要 】

While contemporary prosthetic devices restore some function to individuals who have lost a limb, there are efforts to develop bio-integrated prostheses to improve functionality. A critical step in advancing this technology will be to securely attach the device to remnant bone. To investigate mechanisms for establishing robust implant fixation in bone while undergoing loading, we previously used a topology optimization scheme to develop optimized orthopedic implants and then fabricated selected designs from titanium (Ti)-alloy with selective laser sintering (SLS) technology. In the present study, we examined how implant architecture and mechanical stimulation influence osseointegration within an in vivo environment. To do this, we evaluated three implant designs (two optimized and one non-optimized) using a unique in vivo model that applied cyclic, tension/compression loads to the implants. Eighteen (six per implant design) adult male canines had implants surgically placed in their proximal, tibial metaphyses. Experimental duration was 12 weeks; daily loading (peak load of +/- 22 N for 1000 cycles) was applied to one of each animal's bilateral implants for the latter six weeks. Following harvest, osseointegration was assessed by non-destructive mechanical testing, micro-computed tomography (microCT) and back-scatter scanning electron microscopy (SEM). Data revealed that implant loading enhanced osseointegration by significantly increasing construct stiffness, peri-implant trabecular morphology, and percentages of interface connectivity and bone ingrowth. While this experiment did not demonstrate a clear advantage associated with the optimized implant designs, osseointegration was found to be significantly influenced by aspects of implant architecture. (C) 2012 Elsevier Ltd. All rights reserved.

【 授权许可】

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