In the present study, we used a Digital Image Correlation (DIC) technique to answer the following question: Does a PEEK TKA femoral component induce a more physiologically normal bone strain distribution than a CoCr component?  To achieve this, a DIC test protocol was developed for periprosthetic bone strain assessment using an analog model; the protocol aimed to minimize errors in strain assessment through the selection of appropriate analysis parameters.


 All models were subjected to standing loads on the corresponding polyethylene (ultrahigh-molecular-weight polyethylene) tibial component, and speckle image data were acquired for surface strain analysis using DIC in six repeat tests.  Surface analog bone strain after CoCr implantation indicated strain shielding (R2 = 0.6178 with slope, β = 0.4314) and was lower than the intact case (p = 0.014). 
DIC
Does a PEEK Femoral TKA Implant Preserve Intact Femoral Surface Strains Compared With CoCr?  A polyetheretherketone (PEEK) femoral implant has the potential to promote bone strains closer to that of natural bone as a result of its low elastic modulus compared with cobalt-chromium (CoCr).


 In the present study, we used a Digital Image Correlation (DIC) technique to answer the following question: Does a PEEK TKA femoral component induce a more physiologically normal bone strain distribution than a CoCr component?  One was implanted with a CoCr femoral component and one with a PEEK femoral component.  The strain after implantation with the PEEK implant deviated less from the intact case (R2 = 0.7972 with slope β = 0.939) with no difference (p = 0.231).


 The strain shielding observed with the contemporary CoCr implant, consistent with clinical bone mineral density change data reported by others, may be reduced by using a PEEK implant.


 This bone analog in vitro study suggests that a PEEK femoral component could transfer more physiologically normal bone strains with a potentially reduced stress shielding effect, which may improve long-term bone preservation. 
PEEK
Does a PEEK Femoral TKA Implant Preserve Intact Femoral Surface Strains Compared With CoCr?  A polyetheretherketone (PEEK) femoral implant has the potential to promote bone strains closer to that of natural bone as a result of its low elastic modulus compared with cobalt-chromium (CoCr).


 In the present study, we used a Digital Image Correlation (DIC) technique to answer the following question: Does a PEEK TKA femoral component induce a more physiologically normal bone strain distribution than a CoCr component?  One was implanted with a CoCr femoral component and one with a PEEK femoral component.  Surface analog bone strain after CoCr implantation indicated strain shielding (R2 = 0.6178 with slope, β = 0.4314) and was lower than the intact case (p = 0.014).  The strain shielding observed with the contemporary CoCr implant, consistent with clinical bone mineral density change data reported by others, may be reduced by using a PEEK implant.



CoCr