The Three-dimensional Finite Element Model And Biomechanical Analysis Of The New Locking Plate For Proximal Humeral

【Objectives】 The biomechanical characteristics of the four-part proximal humerusfractures treated with The New Locking Plate is unclear. A biomechanical finite elementanalysis of the stress patterns and peak stresses involved with The New Locking Platefixation and AO-PHILOS+Screws fixation for the four-part proximal humerus fractureswas performed.【Methods】 Finite element models of The New Locking Plate fixation andAO-PHILOS+Screws fixation for the four-part proximal humerus fractures were built andthe results were compared with two models of fracture fixation process in shoulderabduction of four different functional position.【Results】In a simulated in four different function position of shoulder abductionstress comparison: in shoulder abduction0°the maximum Von Mises stress, The NewLocking Plate fixation (1033.0Mpa)> AO-PHILOS (743.1Mpa); the maximum Von Misesstress in shoulder abduction30°, The New Locking Plate (904.1Mpa)> AO-PHILOS(692.4Mpa); in shoulder abduction60°, The New Locking Plate (888.1Mpa)>AO-PHILOS (486.4Mpa); maximum Von Mises stress in abduction90°, The NewLocking Plate (1062.0Mpa)> AO-PHILOS (393.5Mpa). Two models stress distributioncomparison: in shoulder abduction0°,30°,60°stress distribution of new locking platewith AO-PHILOS+Screws stresses are concentrated in the medial support,there is nosignificant difference; while in abduction90°the new locking plate and AO-PHILOS+Screws fixation stresses are concentrated in medial support, AO-PHILOS stressconcentration range is larger than the new locking plate, the difference is significant. Thenew locking plate relative stress disperse stress, the stress distribution. there is nosignificant difference between the two models of fracture fixation in maximumdisplacement in the shoulder abduction activities. 【Conclusions】Two internal fixation treatments of complex four-part proximalhumerus fractures, stress distribution were not significantly different, the stress isconcentrated at the medial support, have shown obvious biomechanical stability, bothstress-shielding effects are obvious. But compared to the new locking plate, AO-PHILOS+Screws fixation model stress concentration was slightly larger than the other at themedial support. Therefore, we believe the new locking plate for the unique anatomicaldesign and four-part proximal humeral fracture fixation also can get a better biologicalproperties. 【Objectives】To compare the stress patterns and peak stresses of greater tuberosityfractures of the humerus treated by three different fixation model with finite elementanalysis【Methods】Through finite element analysis,to build the stress patterns and peak stressesof greater tuberosity fractures of the humerus treated by three different fixation models(screws, tension band, locking plate, respectively)and the results were were compared withthree models of fracture fixation process in shoulder abduction of four different functionalposition.【Results】In a simulated in four different function position of shoulder abduction stresscomparison: the maximum Von Mises stress in shoulder abduction0°,Tension band(568.4MPa)> Screws (318.7MPa)> The New Locking Plate (298.9MPa). the maximumVon Mises stress in shoulder abduction30°, Tension band (886.3MPa)> humeral greatertuberosity new locking plate (291.1MPa)> Screws (266.0MPa). in shoulder abduction60°,Tension band (817.0MPa)> humeral greater tuberosity new locking plate (282.5.MPa)>Screws (277.6MPa); maximum Von Mises stress in abduction90°, Tension band(593.4MPa)> Screws (284.3MPa)> humeral greater tuberosity new locking plate(247.8MPa).Three internal fixation stress distribution comparison: new locking plate and the stress is concentrated and dispersed with posterolateral screws on; tension with a stressconcentration in the "8" in the middle is more concentrated, fixed area of minimal stressconcentration significantly; screws small size, the relative stress concentration。Generally,three different fixed overall stress are gradually reduced in the four different shoulderabduction process, but The New Locking Plate dispersed stress transfer faster and moreergonomic features; tension with stress to "8" in the middle is more concentrated, a verysmall contact area, the stress concentration is more significant, the stress dispersion slowly;the small screw fixed size, the more significant stress concentration, relatively speaking,the dispersion of stress transfer are also evident. there is no significant difference there isno significant difference between the two models of fracture fixation in maximumdisplacement in the shoulder abduction activities.【Conclusions】The New Locking Plate model showed a stress distribution similar to theintact shoulder, The locking plates show more obvious biomechanical stability than screwsand tension band, which provides a new and better choice for treatment of the isolatedgreater tuberosity fractures of the humerus.