| Objective1.Through clinical retrospective study to analyze the differences in the incidence of unilateral intertrochanteric fractures and femoral neck fractures,analyze the causes of different types of hip fractures in the elderly,based on microscopic syndrome differentiation of TCM,the main stress bones in the fall state The idea of beam affecting the type of hip fracture in the elderly.2.The finite element method was used to simulate the same lateral fall posture,and the effect of the main stress trabecular bone on the crack development of the elderly hip fracture was ve.rified.It provided a new idea and biomechanieal reference for the occurrence mechanism and prevention of hip fracture in the elderly.Methods1.Clinical study:300 patients with aged hip fracture(age≧55 years old)who were hospitalized in the Department of Trauma and Orthopaedics,First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine from January 1,2013 to January 1,2015(including femur)150 cases of intertrochanteric fractures and 150 cases of femoral neck fractures were divided into two groups according to the microscopic syndrome differentiation method of Chinese medicine.The cases were divided into two groups:femoral intertrochanteric fracture group and femoral neck fracture group.SPSS 20.0 software was used to treat the elderly hip fractures.The incidence and two different fracture types were statistically different from gender,age,Singh index,and cortical bone thickness.The def’inition of P<0.05 was statistically significant.2.Experimental study:1 Collect hip CT data of a qualified normal male volunteer,establish a three-dimensional model of the left hip skeleton through Mimics19.0 software and Geomagic studio 2017 software,and import it into Hypermesh 14.0 software for meshing.According to the Singh index classification,six models AF corresponding to 1-6 levels are obtained(the F model corresponds to the 6-level Singh index model,which is the normal group model),and the material attributes are assigned and parameterized for the six models.2 lateral fall is the most common cause of hip fracture in the elderly.The study confirmed that when the fall is 30° with the horizontal plane and 135° with the sagittal plane,it is most likely to cause intertrochanteric fractures between the femoral neck and the femur.In Hypermesh In the 14.0 software,the angles of the six models were set,the distal end of the femur was completely fixed,and the concentrated force perpendicular to the ground was loaded 750N.The K file was generated and imported into the LS-DYNA software to solve the problem.After the operation result was obtained,the dynamic result was obtained in Hyperview.Observed.The main observations were model fracture initiation time,model fracture type and Von-Mises stress cloud map.Results1.Overall,the proportion of women with hip fractures was higher than that of men.The proportion of women with femoral neck fractures and intertrochanterie fractures was higher than that of men.There was no significant difference in the proportion of males and females between the two groups(=3.597,P>The mean age of patients with femoral neck fracture was 78.057.537 years;the intertrochanteric fracture group was 80.49±6.918 years old.The average age of intertrochanteric fracture group was significantly larger than that of femoral neck fracture group.There was significant difference between the two groups(P<0.05);the mean CTI of the cortical thickness index was 0.483±0.077 in the femoral neck fracture group and 0.462±0.075 in the intertrochanteric fracture group.The mean CTI of the intertrochanteric fracture group was significantly smaller than that of the femoral neck fracture group.The dif’ference was(=2.403,P>0.05);the mean Singh index was 4.410±0.696 in the femoral neck fracture group and 4.050±0.792 in the intertrochanteric fracture group.The mean Singh index was significantly smaller in the intertrochanteric fracture group than in the femoral neck fracture group.There was a statistically significant difference between the two groups(P<0.05).2.When the femur is at 30° from the horizontal plane and falls at 135°from the sagittal plane,the starting time of hip fracture fracture is getting late from model A to model F;model A to model F are femoral neck fractures.There is no significant difference in the position of the fracture line;from model A to model F,the overall stress experienced by the model is getting smaller and smaller.Conclusions1.To establish a three-dimensional finite element model of the proximal femur with osteoporosis,which provides an experimental basis for further simulation and more accurate study of hip fracture in the elderly.2.The main stress trabeculae in the proximal femur are mainly resisting and buffering bending strain,which have the function of buffering and dispersing the stress of hip,and have certain influence on crack propagation of hip fracture in the elderly.3.The thickness of cortical bone is closely related to the type of hip fracture.The thinning of femoral intertrochanteric cortex may be one of the related factors leading to different types of hip fracture,especially in elderly patients. |
