Three-Dimensional Finite Element Analysis Of Biomechanical Pullout Strength Characteristics Of Screw With Different Materials And Structures In Cancellous Bone

To demonstrate whether the material properties and structure affect the pullout strength of screw in cancellous bone, 3D finite element analysis (FEA) method was performed to simulate the models of four different structure types of screws with 316L stainless steel and biodegradable magnesium pulled out in cancellous bone. After verified FEA method due to results comparison with prior studies of solid screw in cancellous bone with three densities, models determine that biodegradable magnesium material has the same fixation capacity with traditional screw material. Since side holes in current cannulated screw made pullout strength decreasing and mises stress increasing of screws, the study explored that package of bone flap in cannuated pore could favorably help the structure improve biomechanical characteristics of the screw. This study provide a basis for design and application of biodegradable screws, which could help the development of osteoporotic implant research.