TY - JOUR
T1 - The Adaptive Multimode Lubrication in Knee Prostheses with Artificial Cartilage during Walking
AU - Murakami, T.
AU - Sawae, Y.
AU - Higaki, H.
AU - Ohtsuki, N.
AU - Moriyama, S.
N1 - Funding Information:
The authors wish to express their appreciation to Mr. Y. Nakanishi, graduate student at Kyushu University for his cooperation and Dr. J. B. Medley, University of Waterloo, for his advice on PI model . The measurement of AFM was conducted using AFM at the Center of Advanced Instrumental Analysis, Kyushu University. Sodium hyaluronate was prepared by Seikagaku Corporation and polyurethane was supplied by Dow Chemical Japan Ltd. Financial support was given by the Grant-in-Aid for Scientific Research of The Ministry of Education, Science, Sports and Culture, Japan ((A) No.07558256, (B) No.07458237, International Scientific Research (Joint Research) No.07044159 ).
PY - 1997
Y1 - 1997
N2 - The lubricating performance of total knee prosthesis models with compliant layer as artificial cartilage was evaluated and discussed from the viewpoint of adaptive multimode lubrication. The minimum film thickness and inclination of rubbing surface during walking were estimated by numerical analysis based on the plane inclined surface model for polyvinylalcohol (PVA) hydrogel and polyurethane. The numerical results show the effectiveness of softer material on fluid film formation during walking, although surface inclination during swing phase is larger for polyurethane than PVA hydrogel. The actual fluid film formation in knee prostheses during walking was examined by measurement of degree of separation by electric resistance method and frictional force in simulator tests. Under walking condition lubricated with lubricants of appropriate viscosity, considerable elastohydrodynamic film was formed corresponding to numerical analysis. Under thin film conditions lubricated with low viscosity lubricants where significant local direct contact occurred between rubbing surfaces due to breakdown of fluid film, the addition of proteins remarkably decreased friction and suppressed stick-slip for PVA, but increased friction for polyurethane. The addition of phospholipid liposomes had an effect in reducing of friction after repetition of rubbing process in walking motion. The adsorbed film formation of synovia constituents on stainless steel plate was observed by atomic force microscopy.
AB - The lubricating performance of total knee prosthesis models with compliant layer as artificial cartilage was evaluated and discussed from the viewpoint of adaptive multimode lubrication. The minimum film thickness and inclination of rubbing surface during walking were estimated by numerical analysis based on the plane inclined surface model for polyvinylalcohol (PVA) hydrogel and polyurethane. The numerical results show the effectiveness of softer material on fluid film formation during walking, although surface inclination during swing phase is larger for polyurethane than PVA hydrogel. The actual fluid film formation in knee prostheses during walking was examined by measurement of degree of separation by electric resistance method and frictional force in simulator tests. Under walking condition lubricated with lubricants of appropriate viscosity, considerable elastohydrodynamic film was formed corresponding to numerical analysis. Under thin film conditions lubricated with low viscosity lubricants where significant local direct contact occurred between rubbing surfaces due to breakdown of fluid film, the addition of proteins remarkably decreased friction and suppressed stick-slip for PVA, but increased friction for polyurethane. The addition of phospholipid liposomes had an effect in reducing of friction after repetition of rubbing process in walking motion. The adsorbed film formation of synovia constituents on stainless steel plate was observed by atomic force microscopy.
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U2 - 10.1016/s0167-8922(08)70466-8
DO - 10.1016/s0167-8922(08)70466-8
M3 - Article
AN - SCOPUS:33751048910
VL - 32
SP - 371
EP - 382
JO - Tribology Series
JF - Tribology Series
SN - 0167-8922
ER -