The comparison of stress and strain between custom-designed bone plates (CDBP) and locking compression plate (LCP) for distal femur fracture.

BACKGROUND: Distal femur fracture is considered one of the most common fractures due to high-energy traumas such as car accidents or low-energy traumas such as osteoporosis. Locking plates are orthopedic implants used for stabilized femur fracture. Thus, designing a bone plate fitted exactly with the patient's bone and correctly fixing bone segments are required for better fracture healing. OBJECTIVES: This study aims to design a bone plate based on anthropometric characteristics of patients' femurs and compare performing custom-designed bone plates (CDBP) with the locking compression plate (LCP) by finite element method. MATERIALS AND METHODS: In this analytical study, a 3D model of four patients' femur and CDBP were firstly designed in MIMICS 19.0 based on the patient's femur anatomy. After designing the bone plate, the CDBPs and LCP were fixed on the bone and analyzed by finite element method (FEM) in ANSYS, and stress and strain of bone plates were also compared. RESULTS: The maximum principal stress for all 3D models of patients' fracture femur by CDBPs was stabilized better than LCP with a decrease by 39.79, 12.54, 9.49, and 20.29% in 4 models, respectively. Also, in all models, the strain of CDBPs is less than LCP. Among the different thicknesses considered, the bone plate with 5 mm thickness showed better stress and strain distribution than other thicknesses. CONCLUSION: Customized bone plate designed based on patient's femur anatomical morphology shows better bone-matching plate, resulting in increasing the quality of the fracture healing and fails to any need for additional shaping. TRIAL REGISTRATION NUMBER: Design and analysis of an implant were investigated in this study. There was no intervention in the diagnosis and treatment of patients and the study was not a clinical trial.