Biomechanical Comparison Of Triple Endobutton Technique And Double Endobutton Technique For Reconstruction Of Acromioclavicular Dislocation

Objective:A three-dimensional finite element model was established to compare the biomechanical results of Triple Endobutton and Double Endobutton reconstruction of acromioclavicular joint dislocation.Methods:3D solid modeling of the shoulder joint was carried out by using the virtual finite element method.The dislocation of the acromioclavicular joint was used as the injury model.Three micro metal buttons and two No.5 fiber sutures were used to reconstruct the acromioclavicular joint on the injury model.The maximum equivalent stress(MES)and total displacement of clavicle,button and suture were analyzed.Results: Compared with the Double Endobutton reconstruction,the stress on the clavicle and Endobutton of the Triple Endobutton reconstruction is smaller,which is53.6% and 104% lower,respectively.The total displacement on the clavicle and Endobutton of the Triple Endobutton reconstruction was smaller,which decreased by43.2% and 34.2%,respectively.The stress of Triple Endobutton reconstruction on the suture line is obviously reduced and the stress distribution is more balanced.The stress of Triple Endobutton suture line is 146.97 MPa,155.97 MPa,212.22 MPa,199.84 MPa,and the stress of double Endobutton suture line is 386.57 MPa,413.7MPa.The total displacement of the clavicle in the normal model was 0.9116 mm,and that in the Triple Endobutton reconstruction was 0.9515 mm.There was no significant difference between the two models.Conclusions:Compared with the Double Endobutton reconstruction,the maximum equivalent stress and displacement of clavicle and implant of the Triple Endobutton reconstruction of the coracoclavicular ligament are smaller,and the biomechanical results of the Triple Endobutton reconstruction are closer to the original intact ligament,which can better restore the function of the coracoclavicular ligament,and the acromioclavicular joint is more stable.