Study On Healing Effects Of CF/PEEK Bone Plate And The Design Principle Of Bone Plate

Bone plates have been widely used in internal fixation for fracture healing. After the broken bones are fixed, its activity is determined by the load, the construction stiffness of fixation system and bridging tissue. The traditional bone plates are often made of metallic materials which generally result in a series disadvantages to fracture healing, including the mismatch between the elastic modulus of them and the cortical bone, leading to "stress-shielding effect", poor corrosion resistance and fatigue resistance, leading to the failure of fixation, and too large contact area between the plate and the bone, retarding the blood supply of the bone. Carbon fibre reinforced poly-ether-ether-ketene composite (CF/PEEK) can overcome the above shortcomings. Furthermore the composite is radiolucent for X-ray, which is benefit for the observation and analysis after operation. These make the CF/PEEK to be ideal for bone plates. In the paper, the fixation effect of CF/PEEK bone plate and the design principle of bone plate are studied, which is the basis for CF/PEEK bone plate design in the next step. The main contents and results are as followings.Using FEA software ANSYS, three mechanical models of bone plate fixation (traditional screw fixation (pattern one), screw omitted fixations (pattern two and three) are established, and the fixation effects of CF/PEEK bone plate are analyzed. The results indicate that: 1) compared with metallic bone plates, CF/PEEK plate is more helpful for fracture healing due to the reasons of lower stress concentration within bone plates and screws, evener strain distribution within broken bones and minimum strain increase within intact bone, which makes more area of intact bone falls into the physiological strain range; 2) compared of three fixation patterns shows : for metallic bone plates, pattern three is more advantageous to healing for increasing minimum strain within intact bone and evener strain distribution within broken bone ; for CF/PEEK bone plate both the pattern two and pattern three are advantageous to fracture healing.By systematic study on the design principle of bone plate, the main principles about bone plate design are gained. The biocompatibility and mechanical property...