Hip joint replacements represent the most effective way of treatment for patients suffering from joint diseases.Despite the rapid improvement of implant materials over the last few decades,limited longevity associated...Hip joint replacements represent the most effective way of treatment for patients suffering from joint diseases.Despite the rapid improvement of implant materials over the last few decades,limited longevity associated with wear-related complications persists as the main drawback.Therefore,improved tribological perfor-mance is required in order to extend the service life of replacements.The effect of surface texturing of ultra-high molecular weight polyethylene(UHMWPE)acetabular cup was investigated in the present study.Unique tilling method was utilized for manufacturing the dimples with controlled diameter and depths on the contact surface of the cup.The experiments with four commercial femoral components and two model lubricants were realized.The main attention was paid to a coefficient of friction considering the differences between the original and the dimpled cups.Results showed remarkable lowering of friction,in general.Focusing on the simulated human synovial fluid,friction was reduced by 40%(alumina ceramic),38.8%(zirconia toughened ceramic),25.5%(metal),and 9.9%(oxinium).In addition,the dimples helped to keep the friction stable without fluctuations.To conclude,the paper brings a new insight into frictional behaviour of the hip replacements during running-in phase which is essential for overall implant lifespan.It is believed that proper surface texturing may rapidly improve the life quality of millions of patients and may lead to considerable financial savings.展开更多
Former research work about the modeling of hip joint focus on the uppersegment of femoral, and assumes the acetabulum cup is sphere concave, and the acetabulum prosthesesis semisphere. A method of acquiring the point ...Former research work about the modeling of hip joint focus on the uppersegment of femoral, and assumes the acetabulum cup is sphere concave, and the acetabulum prosthesesis semisphere. A method of acquiring the point data on the surface of the hipbone using the reverseengineering technology is presented. After analyzing the acetabulum surface fitting error, arotation ellipsoid CAD model is applied to fit the acetabulum surface, and then optimizationtechnique is used to find the geometric parameters of the model. The fitting error between thesphere and rotation ellipsoid is compared and gets the result that the fitting error of rotationellipsoid is smaller than sphere, and the rotation ellipsoid can describe the shape of theacetabulum better.展开更多
基金The research was.carried out under the project JSPS/OF280,PE17046with financial support from the Japan Society for the Promotion of Science.This research was also supported by the project FSI-S-17-4415with financial support from the Ministry of Education,Youth and Sports of the Czech Republic(MEYS).
文摘Hip joint replacements represent the most effective way of treatment for patients suffering from joint diseases.Despite the rapid improvement of implant materials over the last few decades,limited longevity associated with wear-related complications persists as the main drawback.Therefore,improved tribological perfor-mance is required in order to extend the service life of replacements.The effect of surface texturing of ultra-high molecular weight polyethylene(UHMWPE)acetabular cup was investigated in the present study.Unique tilling method was utilized for manufacturing the dimples with controlled diameter and depths on the contact surface of the cup.The experiments with four commercial femoral components and two model lubricants were realized.The main attention was paid to a coefficient of friction considering the differences between the original and the dimpled cups.Results showed remarkable lowering of friction,in general.Focusing on the simulated human synovial fluid,friction was reduced by 40%(alumina ceramic),38.8%(zirconia toughened ceramic),25.5%(metal),and 9.9%(oxinium).In addition,the dimples helped to keep the friction stable without fluctuations.To conclude,the paper brings a new insight into frictional behaviour of the hip replacements during running-in phase which is essential for overall implant lifespan.It is believed that proper surface texturing may rapidly improve the life quality of millions of patients and may lead to considerable financial savings.
基金This project is supported by China Post Doctor Science FoundationShanghai Jiaotong University-Shanghai Second Medical University Cooperation Foundation.
文摘Former research work about the modeling of hip joint focus on the uppersegment of femoral, and assumes the acetabulum cup is sphere concave, and the acetabulum prosthesesis semisphere. A method of acquiring the point data on the surface of the hipbone using the reverseengineering technology is presented. After analyzing the acetabulum surface fitting error, arotation ellipsoid CAD model is applied to fit the acetabulum surface, and then optimizationtechnique is used to find the geometric parameters of the model. The fitting error between thesphere and rotation ellipsoid is compared and gets the result that the fitting error of rotationellipsoid is smaller than sphere, and the rotation ellipsoid can describe the shape of theacetabulum better.
