The Finite Element Simulation And Experiments Of The Interface Integration After Articular Cartilage Defect Repair

Articular cartilage defects has become a more common clinical disease,has a higher incidence of a disease,and not timely treatment may lead to defect continues to expand,and finally lead to osteoarthritis,bring patients great pain.Cartilage tissue engineering as a kind of more permanent repair cartilage defect treatment becomes the focus of tissue engineering.To improve the quality,the tissue engineering cartilage has a huge impact.But if inappropriate implanted tissue engineering cartilage will change the knee joint complex biomechanical environment,and make the artificial cartilage and host cartilage integration problems,and may damage cells directly,or through the biological factors to guide the cells from the formation of cartilage matrix,and hinder the cartilage defect parts of regeneration,finally cause the failure of transplantation.So studying the cartilage repair mechanics environment and exploring the best mechanical properties of artificial cartilage is very important.This paper uses ABAQUS two-dimensional finite element model of solid and liquid phase,including cartilage of porous and viscoelastic characteristics,different layers of different material properties,etc.And we research the influence of mechanical state by different material properties and different amount of compression and the integration of repair area.The cartilage compression experiment,combined with the digital correlation technique for image data processing,discusses the influence of strain distribution by compression on repair area..And The comparison with experimental data and simulation data is used to verify the correctness of the simulation results.The results show that the joint surface with integrated contrast without integration has good mechanical environment.In the absence of integration,there has the phenomenon of cracking,the relative slip on both sides of the interface,pore pressure slightly high,and the velocity is too fast at cracking and so on.The maximum relative slip is in an surface area where is the host cartilage combined with artificial cartilage,and stress concentration occur.Too high or too low elastic modulus of artificial cartilage are not suitable for transplantation,similar with the middle host cartilage has good mechanical properties.The increased amount of compression combined with the biggest influence,intensifying the combination of the stress concentration and cracking phenomenon,but also not conducive to the mutual transfer of nutrients.We should choose artificial cartilage transplants which close to the host cartilage in clinical treatment,and the patients should avoid too intense exercise after transplantation.Due to the process of cartilage defect repair area will influence on the mechanics of the repair as a result,the difference of mechanical state about integration is bigger,the clinical restoration should focus on this issues.