Biomechanical Investigation of Locking Compression Plate for the Treatment of Distal Femoral Fractures Using Finite Element Analyses and Mechanical Tests

• Main Authors: Sung-Min Hsu, 徐嵩閔
• Other Authors: Ching-Kong Chao
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/4d6evb

碩士 === 國立臺灣科技大學 === 機械工程系 === 103 === High-energy impact and osteoporosis are the main causes of femoral fractures. Fixation stability can make a difference between success and failure in surgical operations. Locking-plate system has been widely used in the treatment of a big variety of bone fractures. The chance of occurring complications has been significantly reduced thanks to the invention of the Less Invasive Stabilization System (LISS).There are many screw holes on the plate allow surgeons to insert screws. The number and pattern of screws in use are critical because of the strong link to fixation stability. However, the biomechanical behaviors of plating system with different number and pattern of screw haven’t been investigated and studied in a comprehensive model. Therefore, the aim of this study is to obtain the biomechanical properties, using diverse numbers and patterns of screw and fracture sites in a relatively comprehensive numerical model. The numerical model used in this study includes lower three segments of lumbar (cortical and cancellous bone), discs, pelvis, joints and femur. They are all created by applying the technique, Computer Tomography Scan(CTS). The plating system including locking plate, screws is developed with the software Solidworks. All numerical parts are imported into ANSYS 14.5 to do analyses. This study takes into account two models (lumbar-pelvis-femur model and only femur model), three fracture sites, eight different screw numbers and six screw configurations. Stresses on the top surface of bone plate and displacement of whole system are available in the numerical results. Biomechanical experiments are conducted with the equipment, INSTRON-8872. Six varying number of screws in use are chosen to carry out compression tests. Force-displacement curves are obtained during the biomechanical tests. Numerical and experimental outcomes are compared in the form of displacement and stiffness. Biomechanical experiments and numerical analyses show that less number of screws in use can raise the displacement of whole system. The screw configurations with shorter working length are most likely to have low displacement as a result. Nearer to distal end fracture occurs, more unstable the system would be.