• 한국정밀공학회지
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• 제24권2호
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• pp.140-148
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• 2007

THRA(Total Hip Replacement Arthroplasty) has been widely used for several decades as a viable treatment of otherwise-unsolved hip problems. In THRA surgery, cement mantle thickness is critical to long-term implant survival of femoral stem fixed with cement. Numerous studies reported thin or incomplete cement mantle causes osteolysis, loosening, and the failure of implant. To analyze the effect of femoral stem rotation on cement thickness, in this study, we select two most popular stems used in THRA. Using CAD models obtained from a 3D scanner, we measure the cement mantle thickness developed by the rotation of a femoral stem in the virtual space created by broaching. The study shows that as the femoral stem deviates from the target coordinates, the minimum thickness of cement decreases. Therefore, we recommend development of a new methodology for accurate insertion of a femoral stem along the broached space. Also, modification of the stem design robust to the unintentional movement of a femoral stem in the broached space, can alleviate the problem.

• Structural Engineering and Mechanics
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• 제66권1호
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• pp.37-43
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• 2018

In orthopedic surgery and in particular in total hip arthroplasty, the implant fixation is carried out using a surgical cement called polymethylmethacrylat (PMMA). This cement has to insure a good adhesion between implant and bone and a good load distribution to the bone. By its fragile nature, the cement can easily break when it is subjected to a high stress gradient by presenting a craze zone in the vicinity of inclusion. The focus of this study is to analyze the effect of inclusion in some zone of cement in which the loading condition can lead to the crack opening leading to their propagation and consequently the aseptic loosening of the THR. In this study, the fracture behavior of the bone cement including a strange body (bone remain) from which the onset of a crack is supposed. The effect of loading condition, the geometry, the presence of both crack and inclusion on the stress distribution and the fracture behavior of the cement. Results show that the highest stresses are located around the sharp tip of bony inclusion. Most critical cracks are located in the middle of the cement mantle when they are subjected to one leg standing state loading during walking.

• 대한의용생체공학회:의공학회지
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• 제29권3호
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• pp.212-221
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• 2008

The total hip replacement (THR) has been used as the most effective way to restore the function of damaged hip joint. However, various factors have caused some side effects after the THR. Unfortunately, the success of the THR have been decided only by the proficiency of surgeons so far. Hence, It is necessary to find the way to minimize the side effect caused by those factors. The purpose of this study was to suggest the definite data, which can be used to design and choose the optimal hip implant. Using finite element analysis (FEA), the biomechanical condition of bone cement was evaluated. Stress patterns were analyzed in three conditions: cement mantle, procimal femur and stem-cement contact surface. Additionally, micro-motion was analyzed in the stem-cement contact surface. The 3-D femur model was reconstructed from 2-D computerized tomography (CT) images. Raw CT images were preprocessed by image processing technique (i.e. edge detection). In this study, automated edge detection system was created by MATLAB coding for effective and rapid image processing. The 3-D femur model was reconstructed based on anatomical parameters. The stem shape was designed using that parameters. The analysis of the finite element models was performed with the variation of parameters. The biomechanical influence of each parameter was analyzed and derived optimal parameters. Moreover, the results of FE A using commercial stem model (Zimmer's V erSys) were similar to the results of stem model that was used in this study. Through the study, the improved designs and optimal factors for clinical application were suggested. We expect that the results can suggest solutions to minimize various side effects.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.979-980
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• 2010

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.999-1000
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• 2009

• 대한정형외과학회지
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• 제54권5호
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• pp.377-383
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• 2019

고관절의 생역학은 고관절에서 체중이 관절면을 통해 전달되는 역학적인 원리를 이해하고 탐구하는 학문이다. 이러한 기초 과학 지식은 퇴행성 관절의 병리와 고관절 치환술 등 다양한 분야에 적용될 수 있다. 특히 고관절의 생역학에 대한 이해를 통해 인공 고관절 치환물의 재료와 설계 및 고정과 관련된 고관절 치환술 분야의 발전을 이루어 왔으며, 수술 방법의 선택, 치환물의 선택 및 위치 등 다양한 부분에 적용될 수 있다. 더욱이 환자의 보다 나은 임상 결과를 얻기 위해서는 고관절의 생역학을 잘 이해하는 것이 필수적이다. 따라서 여기서는 고관절의 생역학을 접근하는 데 필요한 기본적인 지식과 정상 고관절 및 인공 고관절의 생역학적 특성을 알아보고자 한다.

• 한국임상수의학회지
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• 제36권4호
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• pp.229-232
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• 2019

Total Hip Replacement in a patient with chronic coxofemoral joint dislocation is a challenging problem because chronic coxofemoral joint dislocation causes severe morphological changes. These challenging factors make surgery more difficult and increase the possibility of postoperative complications including cup implant dislocation and prosthetic joint luxation. All patients were diagnosed having at least 2 months of coxofemoral joint dislocation. On physical examination, crepitus was noted in the coxofemoral joint. Radiographs revealed hip joint dislocation with mild to severe degenerative changes. Total hip replacement was planned for all patients. Dorsal acetabular rim deficiency in 3 cases was augmented using a locking plate and polymethylmethacrylate bone cement. All cases have shown difficulty in prosthetic joint reduction. Pectineus and rectus femoris muscle origin were released in all cases. At 12 months follow up, all patients showed satisfactory ambulation. The issues on perioperative prosthetic joint reduction and luxation due to chronic coxofemoral joint luxation with muscle contracture and dorsal acetabular rim deficiency can be resolved by muscle releasing and dorsal acetabular rim augmentation.

• Structural Engineering and Mechanics
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• 제88권6호
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• pp.583-588
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• 2023

Total hip replacement is a crucial intervention for patients with fractured hips who face challenges in natural recovery. The design of durable prostheses requires a comprehensive understanding of the natural processes occurring in bone. This article focuses on static loading analysis, specifically during stumbling activity, aiming to enhance the longevity of prosthetic implants. Three distinct implants, Charnley, Osteal, and Thompson, were selected for a detailed study to determine the most appropriate model. The results revealed critical insights into the distribution of Von Mises stresses on the components of femoral arthroplasty, including the cement, implant, and cortical bone. Furthermore, the examination of shear stress within the cement emerged as a pivotal aspect for all three implants, playing a crucial role in evaluating the performance and durability of hip prostheses. The conclusions drawn from this study strongly suggest that the Thompson model stands out as the most suitable choice for hip joint implants.

• 한국세라믹학회지
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• 제36권12호
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• pp.1381-1389
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• 1999

• Hip & pelvis
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• 제35권1호
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• pp.47-53
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• 2023

Purpose: The purpose of this study is to compare the radiological results of fixation using the femoral neck system (FNS) and cannulated screw (CS) for treatment of femoral neck fractures. Materials and Methods: A retrospective study of patients with femoral neck fractures who underwent internal fixation and had follow-up of more than six months from 2010 to 2020 was conducted. A total of 87 patients were enrolled in the study. The FNS group included 20 patients and the CS group included 67 patients. Classification of fractures was performed according to Garden and Pauwels classification. Operation time, intraoperative blood loss, sliding distance of the implant, lateral soft tissue irritation caused by implants, and complications were evaluated. Results: The mean operation time was 40.30 minutes in the FNS group and 46.84 minutes in the CS group. The mean intraoperative bleeding volume was 51.25 mL in the FNS group and 72.16 mL in the CS group. Bone union was achieved in 18 patients in the FNS group (90.0%) and in 61 patients in the CS group (91.0%). The mean sliding distance of the implant was 4.06 mm in the FNS group and 3.92 mm in the CS group. No patients in the FNS group and 12 patients in the CS group complained of soft tissue irritation. Conclusion: A shorter operative time, less intraoperative bleeding, and less irritation of soft tissue were observed in the FNS group. FNS could be an alternative to CS for fixation of femoral neck fractures.