Bone fracture is one of the most frequent damage happening to the human body. Orthopedic screws and plates are used for fracture fixation and allow bone to have a proper healing. But commercial bone plates causes problems in blood supply and bone mass decreases in long time. Also applying plates on bone fracture in some cases are complicated. Lag plate is a new design for dynamic compression plates that some of Mashhad Orthopedic Research Center professors made. This small plate has a hook and a dynamic hole that inserting the hook in the one side of fracture bone and inserting the screw in the other side make required pressure between bone segments. In this study the function of lag plate in tibia fracture fixation compared to a commercial plate with 8 hole. By applying 200 N force to screws, fracture segments was fixed one time with two lag plate and one time with the commercial plate. The results show that lag plate provided sufficient pressure between bone segments and leads the bone to direct healing. Also it shows that lag plate decreased stress shielding in bone so the loss of bone mass will reduce.

Keywords