• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.6
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• pp.62-72
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• 2007

Fracture analysis of human bone is necessary to predict the failure of musculoskeletal structures and to heal them by several possible mechanisms under different loading conditions. But human bone is a complex material, with a multiphase, heterogeneous and anisotropic microstructure. Due to the difficulty of obtaining experimental and clinical results, the importance of numerical analysis and computational simulations in biomechanics are increasing gradually. In this study, stress analysis for human femur model is performed by using the 2-dimensional finite element method(FEM) and its stress distribution is determined. From these results, the fracture mechanic parameters are calculated and the fracture criteria on human femur are investigated and discussed.

• Journal of radiological science and technology
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• v.23 no.2
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• pp.13-19
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• 2000

There were some controversies about direct cause of hip fracture. We attempted to look at 40 osteoporotic proximal femur fractures in women over 50 years between March in 1999 and Febuary in 2000. The bone density of the fracture group and the healthy 85 control group was measured by Dual Energy X-ray absorptiometry(DEXA). The result was compared using age matched paired T test. The results were as follows ; 1. The femoral neck fractures were 14 cases and the trochanteric fractures were 26 cases. Mean age at a fracture was 67.1 years in neck fracture group and 76.5 years in trochanteric fracture. 2. In the control group, the bone density of both side of the proximal femur was measured and it showed statistically no difference between both sides in same person. 3. The bone density of neck, Ward's triangle, trochanter(P<0.05) and lumbar spine(P<0.001) was significantly reduced in the proximal femoral fracture group comparing with the control group. 4. The bone density of neck, Ward's triangle, trochanter(P<0.05) was significantly reduced in the proximal femoral neck fracture group comparing with the control group, but there was no statistical difference in lumbar spine comparing with the control group. 5. The bone density of neck, Ward's triangle, trochanter and lumbar spine(P<0.001) was significantly reduced in the proximal femoral neck fracture group comparing with the control group. We concluded that the bone mineral densities(BMD) of proximal femur and lumbar spine had decreased in hip fractures but that the bone mineral density and T-score % of the proximal femur were statistically lower than that of the lumbar spine. We suggest that measuring the bone mineral density of the proximal femur may reflect the weakness of the proximal femur more precisely than measuring the bone mineral density of the lumbar spine.

• Journal of Korean Physical Therapy Science
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• v.8 no.1
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• pp.841-850
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• 2001

This study was conducted to find out current status and characteristics, so that the result could provide basic data to establish prevention programs for hip fracture among the elderly. The data were coolected from 199 cases hospitalized in 4 university hospitals in Pusan during three years period from January, 1966 to December, 1998. The data were obtained from medical records and by using questionnaires through telephone contact or direct personal interview with the subjects or their family, and were analyzed with x2-test. The results were as follow: The mean age of elderly hip fractured cases was 75.7 years, and 61.8% were female. The average hospital stay of the cases was 30.8 days, and 73.9% survived. Femur neck fracture cases comprised 51.7% of the toral cases, while trochanteric fracture cases comprised 48.3%. The hip fracture occurred more frequently during the day, shown as 66.9%, and the most frequently due to trips(44.2%), followed by slips(322%), c1ash(14.6%), dizziness(7.5%), and 00 on. Femur neck fracture, however, occurred the most frequently due to trips(51.5%) and, on the other hand, trochanteric fracture due to slips(40.6%) and trips(36.5%). About two third of hip fracture(67.8%) occurred inside of the building. The most frequently mentioned location for hip fractures was rooms or floors(32.1%), followed by streets(24.1%), bathrooms(17.6%), stairways(13.1%), and so on. Trochanteric fracture, especially, more frequently occurred inside of the building(71.9%) as compared to femur neck fracture(64.1 %). The rate of independent indoor walking in femur neck fractured cases reduced from 88.3% to 74.8% after fracture incidences, while the rate reduced from 86.0% to 45.8% in trochanteric fracture cases. It indicated that trochanteric fractures affected the walking ability of the elderly more severely that femur neck fractures. In conclusion, hip fracture occurs as a combined result of aging characteristics, environmental factors, and health related characteristics. Future studies that investigaterisk factors of hip fracture in elderly are recommended.

• Journal of the Ergonomics Society of Korea
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• v.27 no.2
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• pp.83-89
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• 2008

Study was developed the metallic plate for fixation in the femur fracture and plates has a firm place in fracture treatment. This plates can be stabilized for fracture fixation as well as biological and dynamical device. The device's designation and sizing has a optimization with bending structural stiffness and strength, known meaning that is reliable regardless of the plate by the short type and long type. The bending strength of the curved metallic long plate has to evaluate a 11,000N and the bending strength of the curved metallic short plate has to evaluate a 6,525N. This see the X-ray image of bending angle made certain of 15$^{\circ}$ at number 2 and same 82.87$^{\circ}$ at number 2, 4, 5, 7, 8, 9, 10 by outside angle, and confirmed 25.26$^{\circ}$ at number 3, 3.68$^{\circ}$ at number 6, 15.64$^{\circ}$ at number 9 by inside angle. This study shows that keep up the metallic plate for fixation in the femur fracture through X-ray Image and the device can be used to support Revision case of Hip Implant and to use a case of Hip screw compression of Hip Neck Fracture. Short plate have a wrapping of femur and long plate have to preserve a pole of femur.

• Journal of Trauma and Injury
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• v.18 no.2
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• pp.87-93
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• 2005

Background: The most frequent fracture seen at the emergency department (ED) in the elderly is a femur fracture whereas they do not know the degree of osteoporosis. We analyzed the degree of osteoporosis in patients with femur fractures and compared patients with only femur fractures (FX) to patients with femur and vertebral fractures (VX) by examining the clinical features, the bone mineral density (BMD), and biochemical markers. Methods: From January 2004 to December 2004, we enrolled prospectively 30 femur fracture patients who visited the ED. The bone mineral densities of the lumbar spine and the femur were examined. Total calcium, phosphate, alkaline phosphatase, osteocalcin, and serum C-terminal telopeptide (s-CTx) were measured. The patients with femur fractures were divided into two subgroups according to the presence of vertebral fracture. Results: All BMDs of the FX group showed osteoporosis. The s-CTx levels were higher than normal. The patients in the FX with VX were older than those in the FX only group, and had lower BMDs. There were no significant differences in markers between the subgroups, but the incidence of trochanteric fractures was higher in FX with VX group than in the FX only group. Conclusion: Femur fractures in the elderly were associated with osteoporosis. In our study, despite a considerable difference in BMD between patients with femur fractures and those with femur fractures combined with vertebral fractures, there was no difference in biochemical markers on bone formation nor in the those of bone resorption. We will further investigate the biochemical markers and BMD in the population of osteoporotic fractures. So those indicators should be helpful for planning treatment and for prevention of FX in the elderly.

• Archives of Plastic Surgery
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• v.35 no.1
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• pp.92-95
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• 2008

Purpose: Heterotopic ossification in pressure sore patients is reported to rarely develop, but once it occurs, it frequently causes joint stiffness and mobilization restriction. The aim of this article is to report our experience of atypical bone growing at femur neck fracture site with chronic, extensive pressure sore in patient with paraplegia secondary to spinal injury. Methods: A 28-year-old male patient presented with atypical bone growth at femur neck fracture site with pressure sore. He had undergone atypical growth bone removal and separation of united iliac bone and femur, and then pressure sore was covered by advanced rotation flap. Results: The patient mobilized hip joint and rode in a wheelchair. Complications such as dehiscence, infection, hematoma and flap necrosis did not occur. Conclusion: We experienced successful correction of atypical bone growth removal and recovery of pressure sore. We report our experience of atypical bone growth of fracture site and the related literature was reviewed.

• Structural Engineering and Mechanics
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• v.60 no.3
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• pp.405-412
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• 2016

Bone is a living material with a complex hierarchical structure that gives it remarkable mechanical properties. Bone constantly undergoes mechanical. Its quality and resistance to fracture is constantly changing over time through the process of bone remodeling. Numerical modeling allows the study of the bone mechanical behavior and the prediction of different trauma caused by accidents without expose humans to real tests. The aim of this work is the modeling of the femur fracture under static solicitation to create a numerical model to simulate this element fracture. This modeling will contribute to improve the design of the indoor environment to be better safe for the passengers' transportation means. Results show that vertical loading leads to the femur neck fracture and horizontal loading leads to the fracture of the femur diaphysis. The isotropic consideration of the bone leads to bone fracture by crack propagation but the orthotropic consideration leads to the fragmentation of the bone.

• Advances in biomechanics and applications
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• v.1 no.1
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• pp.1-14
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• 2014

In this paper, a simple and accurate finite element model coupled to quasi-brittle damage law able to describe the multiple cracks initiation and their progressive propagation is developed in order to predict the complete force-displacement curve and the fracture pattern of human proximal femur under quasi-static load. The motivation of this work was to propose a simple and practical FE model with a good compromise between complexity and accuracy of the simulation considering a limited number of model parameters that can predict proximal femur fracture more accurately and physically than the fracture criteria based models. Different damage laws for cortical and trabecular bone are proposed based on experimental results to describe the inelastic damage accumulation under the excessive load. When the damage parameter reaches its critical value inside an element of the mesh, its stiffness matrix is set to zero leading to the redistribution of the stress state in the vicinity of the fractured zone (crack initiation). Once a crack is initiated, the propagation direction is simulated by the propagation of the broken elements of the mesh. To illustrate the potential of the proposed approach, the left femur of a male (age 61) previously investigated by Keyak and Falkinstein, 2003 (Model B: male, age 61) was simulated till complete fracture under one-legged stance quasi-static load. The proposed finite element model leads to more realistic and precise results concerning the shape of the force-displacement curve (yielding and fracturing) and the profile of the fractured edge.

• 대한정형외과스포츠의학회:학술대회논문집
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• 2004.09a
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• pp.59-59
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• 2004

• Journal of the Korean Society of Radiology
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• v.7 no.5
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• pp.359-364
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• 2013

Femur is the largest bone in the human body which supports the weight of body. A long pipeline shape of femur has little cancellous bone, so that regeneration is difficult when fracture happens. The fracture caused by an accident most frequently occurs at diaphysis. IM Nailing is the surgical method that implants an IM Nail into a medullary cavity for the fixation of fracture parts. However, a secondary fracture may happen if an IM Nail does not penetrate at the center of femur. In this study, a patient-specific femur was manufactured by a 3D printer using the computed tomography images scanned before surgery, which was used for the simulation of IM Nailing. It is expected that this result may prevent the secondary damage, reduce surgical operation time, and increase the precision.