Finite Element Analysis Of Clavicular Hook Plate And Plate Combined With Suture Anchor In The Treatment Of Tossy Ⅲ Acromioclavicular Joint Dislocation

Part 1 Establishment of two surgical treatment finite element models for the treatment of Tossy Ⅲ acromioclavicular joint dislocation with clavicular hook plate and plate combined with suture anchorObjective:To provide a basis for the biomechanical study of the maximum stress values on the clavicle,acromion,and acromioclavicular plate and the stability of the acromioclavicular joint under the two different fixation treatments,based on a thin-section CT image set of the left shoulder joint of a healthy adult male volunteer two finite element models for the surgical treatment of Tossy Ⅲ acromioclavicular dislocation were developed.Methods:A healthy adult male volunteer was selected,and the deformities and lesions around the clavicle,scapula and acromioclavicular joint were excluded through clinical and imaging examinations before CT data collection.A CT scan of the volunteer’s left shoulder joint was performed to obtain a complete acromioclavicular joint scan data set,which was then imported to the Mimics software to establish a three-dimensional digital model of acromioclavicular joint bony tissue.After importing the 3D digital model into the Geomagic studio software to transform the entity,the Solidworks software is used to model the clavicle hook plate and screw and perform the registration combination of the model.In the Hypermesh software,the combined digital model is meshed,and the soft tissue around the acromioclavicular joint and the finite element mesh model of the line anchor are constructed to complete the assignment of material properties.The finite element model of combined acromioclavicular joint dislocation was imported into Abaqus software,and the contact relationship and boundary constraints of the model were set.A vertical downward load of 35N was applied to the scapula,simulating the load-bearing condition of the acromioclavicular joint in a resting state.The force of the model was analyzed,and the actual clinical situation and previous reports were compared and verified.Results:Two finite element models for the treatment of Tossy Ⅲacromioclavicular joint dislocation with simple clavicular hook plate and plate combined with wire anchor were successfully established.After applying a vertical downward load of 35 N to the scapula,the arithmetic predictions showed that the stress distribution of the two surgical treatment finite element models was similar to the clinical reality and the reported results in previous biomechanical literature.Conclusion:The two surgical treatment finite element models for Tossy III acromioclavicular joint dislocation constructed in this study are realistic in geometry and similar in physical properties to the real situation.They can be used for the next step of finite element analysis.Part 2 A compare finite element analysis of clavicular hook plate and hook plate combined with suture anchor for the treatment of TossyⅢ acromioclavicular joint dislocationObjective:To provides a biomechanical basis for the rational selection of relevant surgical procedures in the treatment of Tossy Ⅲ acromioclavicular dislocation.The finite element analysis of the clavicle hook plate for the treatment of Tossy Ⅲ acromioclavicular dislocation was used to investigate the stress distribution on the clavicle,acromion,and clavicle hook plate and the stability of the acromioclavicular joint after the treatment of Tossy Ⅲ acromioclavicular dislocation by comparing the clavicle hook plate alone with the plate combined with suture anchor.Method:Based on the two surgical fixations for Tossy Ⅲ acromioclavicular dislocation finite element models developed in Part Ⅰ,three constrained loading conditions are created.The scapular glenoid was loaded with 70N in three directions:downward,forward,and backward,to simulate the stresses on the acromioclavicular joint in the downward,forward,and backward directions during non-weight-bearing activities of the upper limb,in accordance with previous biomechanical studies.The maximum stresses on the clavicle,acromion,and clavicle hook plates and the relative displacements of the acromioclavicular joint were compared for the same fixation restraint in the two surgical fixation methods with the three different load directions.Results:Under the constrained loading condition 1,the maximum stresses on the clavicle,acromion,and clavicular hook plate on the model of hook plate combined with suture anchor fixation(model two)are 12-14%lower than the hook plate model(model one):the upward displacement value of the distal clavicle in model two is reduced by 12%compared with the model one.Under the constrained loading condition 2 and 3,the maximum stresses value on the acromion and clavicular hook plate in model two are 7-28%lower than in model one.However,the maximum stress on the clavicle is not much different between these two models;there is no significant difference in the displacement value of the distal end of the clavicle between the two models.Conclusion:The predicted results of two finite element models for the surgical treatment of Tossy Ⅲ acromioclavicular dislocations suggest that on the basis of using clavicular hook plate to treat Tossy Ⅲ acromioclavicular joint dislocation,combined with suture anchor repair to replace the rostral collar ligament,can reduce the maximum stress values on the acromion,clavicle,and clavicle hook plates to varying degrees,thus playing a role in reducing the occurrence of stress concentration-related complications.However,the effect of enhancing the stability of the acromioclavicular joint under small load/displacement is not obvious,and it is predicted that it may play a certain stabilizing effect under the condition of large load/displacement of the upper limb,thereby reducing the occurrence of acromioclavicular joint re-dislocation.