Establishment Of Finite Element Model Of Rabbits' Knee Joint And Analysis Of Biomechanics After Anterior Cruciate Ligament Reconstruction

Objective: To establish the animal experimental models of anterior cruciate ligament(ACL)injury and reconstruction with remnant preservation(femoral tensionong and augmented suture)and a finite element modle of rabbits' knee joint.To analyze the biomechanics of this model in the condition of normal,injury and reconstructed anterior cruciate ligament with remnant preservation(femoral tensionong and augmented suture).To evaluate the results of anterior cruciate ligament(ACL)reconstruction and to provide a consensus regarding treatment of ACL injuries.Methods: 20 healthy male New Zealand white rabbits were divided into two groups at random: control group and experimental group.The experimental rabbits' anterior cruciate ligament were broken and taken surgical reconstruction.12 weeks after the operation 1 rabbit were randomly selected and scanned by spiral CT in the control group.Then the experimental group and control group animals were executed respectively and collected all specimen of the knee joint.Tensile experiment tested the graft tendon maximum load and displacement.At last according to the access of spiral CT scan data set up three-dimensional finite element model of knee joint,analyze the biomechanics of this model in the condition of normal,injury and reconstructed anterior cruciate ligament with remnant preservation(femoral tensionong and augmented suture).Results: The rabbit general equilibrium between the two groups,no significant statistical difference.Tensile test results show that: When the ACL normal rabbit can withstand maximum tension is(100.05±1.09)N,the tendon reconstruction after transplantation can withstand the maximum tension is(38.11± 5.04)N,two sets of data between a statistically significant difference(P<0.05).According to obtain the spiral CT scan data successfully establish a rabbit knee joint of the three-dimensional finite elementmode.The finite element mechanics analysis shows: ACL under normal,damage and reconstruction with remnant preservation(femoral tensionong and augmented suture)of three kinds of states tibia platform of inside and outside,inside and outside of the lateral meniscus within the knee joint and femoral condyle biomechanical comparison of differences,Tibia after an ACL injury inside and outside the lateral meniscus within the platform,and the lateral femoral condyle were respectively increased by 23.3%?40.6%?39.8%?32.3%?21.4%?18.5% when the pressure is normal,the force is improved from the previous after reconstruction,but than normal after reconstruction is still respectively increased by 19.3%?11.4%?6.6%?10.7%?13.0%?7.0%.Conclusion: 12 weeks after ACL reconstruction with remnant preservation(femoral tensionong and augmented suture)of tendon transplantation biology performance than normal ACL.The knee joint 3-d finite element mechanics analysis shows:Reconstruction of ACL doesn't fully recover after an ACL injury force situation of each part of the knee joint,but the damage after each part stress distribution are improved.Knee joint reconstruction is necessary after an ACL injury,but still need to continue to improve,to improve the effect of the reconstruction of the ACL.