The Biomechanical Research Of Tui-na Rotating Manipulation Based On The Finite Element Model Of The Knee Injury Joint Ligament

Objective: To collect and analyze the kinematic parameters of the Rotating manipulation method on the knee jiont,to provide the function condition of manipulation for the finite element analysis.Using MRI to collect anatomical tomography images,to create the three-dimensional model of knee joint by using Mimics and Ansys softwares and proceed the damage simulation.Analyzing the stress changes of the knee joint ligament and articular cartilage by the method of the Rotating manipulation,to provide a evidence for the clinical application of the Rotating manipulation.Method: 1?Data conllection and analysis of the kinematic parameters of the Rotating manipulation:Used the Vicon optical motion capture system to collects the kinematics of the Rotating manipulation,and analysed the kinematic data including the three-dimensional displacement?velocity and acceleration,and obtained the kinematic parameters function conditions for the finite element analysis;2?Scaned and obtained the MRI images of the knee joint of healthy and medial collateral ligament injury by using GE Discovery MR 750 3.0T MRI scanner,and established the finite element model of the knee joint based on the biological data of human anatomy using the bioengineering software(Mimics,Ansys etc).comparing the results of stress and displacement of the model with those of in vitro biomechanical study we tested The effectiveness of the model under the the same load and boundary conditions and performed the injury simulation-based verification of the model;3?the regular analysis of biomechanical stress based on the finite element model for the knee joint: by reprogramming the kinematic data of the Rotating manipulation for the computer analog analysis,the computer mechanics function data is synthesized,analysis the corresponding stress change law between the main anatomical structural parts(ligament,articular cartilage)of the knee joint under the dynamic simulation of the rotating manipulation.Results: 1?the kinematic parameters of the three-dimensional direction of the knee joint(x-axis,y-axis,z-axis)between the 2 test cycles is basically no significant difference(p?0.05),indicating the success of the kinematic parameters conllection of the rotating manipulation.The Results shows that the operator proceeded a perfect performance,such as velocity?acceleration?displacement.so the manipulation is relatively stable.The mathematical function condition of the manipulation is good for the finite element analysis;2?Each model is a the High-order 4-Body 10-node mesh model composed of 263966 elements and 452056 nodes.the compress-strain curve of the model was in agreement with the biomechanical experimental results in the other researches,and the model damage simulation succeed,so the model was established and validated successfully;3?the regular stress analysis shows that the maximal stress of articular cartilage and anterior cruciate ligament is most obvious,and the results of different injury degree of knee joint stress are significant difference,especially the degree of injury and anatomical structure of knee joint are significantly correlated,The interaction influence between the degree of injury and the different parts of the joint on the stress is most obvious.Conclusion: 1?the dynamic characteristics of the rotating manipulation are as follows: the operator mainly use the wrist joint and elbow joint to control the movement of rotating manipulation while the hip and knee joint of the subject keep stationary as far as possible,it shows that the rotating manipulation perform even and gentle,ease of operation to keep the leg of subjects doing circular movement;2?both of these construction of normal and injured knee ligament three-dimensional finite element model can reflect the reality of knee ligament anatomy and the biomechanical characteristics of the knee ligament.The finite element model is highly positive for the finite element biomechanical analysis;3?the biomechanical analysis of the main ligament of the knee under the finite element simulation showed the ligament stress regularly changes with the different organization structure,different manipulation rotating angle and different degree of injury,especially the interaction influence between the degree of injury and the injured part was obvious;4?Suggestion of stress analysis results: Because of the biomechanical characteristics of the anatomical parts,the manipulation operation can increase the stress of every parts of the knee joint,but in a certain angle,it can also be appropriate to reduce the stress during the change process of rotation angle.however there were no significant correlation(statistical significance).So the standard rotating manipulation operation is safe and reliable for minor knee injury.it has a great interaction effect on the anterior cruciate ligament and articular cartilage,especially between the degree of damage and the ACL,suggesting that for the severity of the damage at the specific damage site,the manipulation should be used restrainedly.