• 대한핵의학회지
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• 제24권1호
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• pp.124-132
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• 1990

It has been reported that hematoma is one of the most crucial factors in fracture healing since callus formation is disturbed by washing out the hematoma near a fracture site. However, it is not clear why the hamatoma is important and how it plays a role during the fracture healing. In order to investigate the role of hematoma in the process of fracture healing, the osteogenic potential by subperiosteal transplantation have been studied. Experimental fractures by operation were made at the mid-shaft of the tibia in New Zealand white rabbits. Removal of hematoma at the fracture site was done after 2 and 3 days from experimental fracture, and the removed hematoma was transplanted into the subperiosteal area at the mid-shaft of the ulna of each rabbit. As control groups, we have performed 3 different procedures 1) the hematoma was transplanted into the muscular layers at the thigh and forearm; 2) autologous blood clots were transplanted into the subperiosteal area of the ulna; and 3) sham operation without a transplantation into the subperiosteal area. After transplantation, serial bone scintigraphy and simple radiography were performed at 4 days, 1 week, and 2 weeks to detect an abnormality. The results of bone scintigraphy were positive in 5 of 6 experimental group. However, all in three control groups were negative. Histological observation of the positive bone revealed new bone formation with trabeculation. These results suggest the hematoma in fracture site has osteogenic potential in the subperiosteal area which can be demonstrable by bone scintigraphy and histologic findings. Therefore, it is considered that hematoma of the fracture site plays an important role in the process of fracture healing. Further biochemical investigation using various experimental models is mandatory to apply this preliminary result to the treatment of clinical delayed union or nonunion.

• Structural Engineering and Mechanics
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• 제33권5호
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• pp.543-560
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• 2009

The rotating Rayleigh-Timoshenko beam element based on B-spline wavelet on the interval (BSWI) is constructed to discrete short shaft and stiffness disc. The crack is represented by non-dimensional linear spring using linear fracture mechanics theory. The wavelet-based finite element model of rotor system is constructed to solve the first three natural frequencies functions of normalized crack location and depth. The normalized crack location, normalized crack depth and the first three natural frequencies are then employed as the training samples to achieve the neural networks for crack diagnosis. Measured natural frequencies are served as inputs of the trained neural networks and the normalized crack location and depth can be identified. The experimental results of fatigue crack in short shaft is also given.

• Journal of Welding and Joining
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• 제15권6호
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• pp.78-84
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• 1997

Friction welding technique was studied to weld the turbine wheel and shaft of a turbocharger. The welding parameters were selected to investigate the effects of variables on welding quality of Inconel 713C and SCM 440. Experimental results showed that the turbine wheel and shaft could be successfully welded by friction welding. The heat affected zone was identified to be 2 mm from the weld seam. After welding, the hardness profile was found to have sudden increase and decrease for inconel 713C and SCM 440 respectively. Tensile strength of welded specimens was higher than the required strength for all of the studied welding parameters. The central portion of fracture surfaces by bending had no defects such as crack.

• Clinics in Shoulder and Elbow
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• 제15권2호
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• pp.117-122
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• 2012

목적: 전위성 쇄골 간부 골절에서 관혈적 정복술 후 윤곽 성형된 잠김 압박 금속판(precontoured locking compression plate)을 이용하여 내고정을 시행한 환자를 대상으로 방사선학적 결과 및 임상적 결과를 분석하여 윤곽 성형된 잠김 압박 금속판의 유용성을 알아보고자 하였다. 대상 및 방법: 2009년 3월부터 2010년 2월까지 본원에서 쇄골 간부 골절에 대해 윤곽 성형된 잠김 압박 금속판을 이용하여 관혈적 정복 및 금속 고정술을 시행하고 1년 이상의 추시가 가능했던 34예를 대상으로 하였다. 수술 후 방사선학적 결과는 골유합 여부와 성별 및 나이에 따른 골유합 시기의 차이를 평가 하였으며 임상적 결과는 최종 추시 시 quick DASH Score 및 반대측과 관절 운동 범위의 차이를 평가 하여 분석하였다. 결과: 방사선학적 평가에서 모든 예에서 골유합을 얻을 수 있었으며 평균 골유합 기간은 12.3주였으며 성별 및 나이에 따른 골유합 기간은 통계학적으로 유의한 차이를 보이지 않았다(p=0.87). 임상적 평가에서 최종 quick DASH Score는 평균 23.5점 (12~42)이었으며, 최종 추시시 견관절의 운동은 건측과 비교 시 통계학적으로 유의한 차이를 보이지 않았다 (p=0.69). 결론: 전위성 쇄골 간부 골절에 대해 윤곽 성형된 잠김 압박 금속판을 이용한 내고정술은 정확한 해부학적 정복과 견고한 내고정을 유지 할 수 있어 조기 운동이 가능하여 견관절 운동의 회복과 함께 전례에서 골유합을 얻을 수 있어 쇄골 간부 골절 치료에서 유용하게 사용될 수 있다고 사료된다.

• Clinics in Shoulder and Elbow
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• 제19권4호
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• pp.223-228
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• 2016

Background: The aim of study was to confirm the clinical effectiveness and results of wide and single anterior approach for fractures occurring along length of humerus. Methods: A total of 23 patients with humeral fracture were enrolled into our study who were able to participate in at least one year of follow-up. Seven patients had segmental comminuted humeral fractures and 16 patients had distal humeral fractures. We made various tractions of the muscles to expose the proximal and the middle third humerus between the biceps and brachialis and the distal humerus by partial splitting of lateral side of biceps through a single incision. Postoperatively, we measured the Mayo elbow performance index (MEPI). Results: we achieved bone union in all 23 patients. Solid union of the bone was achieved at an average 13.9 weeks. Postoperatively, two complications were observed screw loosening and nonunion. Revision surgery was performed in both patients. The patient with bone nonunion was treated using bone grafts. No postoperative infections or peripheral neuropathies were observed. At the final follow-up (average 20 months), we found that the average MEPI functional score of the patients was 91.7 points regardless of the fracture site. Conclusions: Our whole humerus with a single incision was effective for the treatment of segmental comminuted and distal fractures. we believe it is a useful alternative to preexisting methods of fracture fixation.

• Journal of Trauma and Injury
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• 제23권1호
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• pp.1-5
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• 2010

Purpose: To investigate the results of treatment of reverse oblique trochanteric fractures with compression hip screw. Methods: We reviewed the results of 12 cases of reverse oblique trochanteric fracture treated with compression hip screw from January 2000 to December 2006 which could be followed up for more than 1 year. The mean follow up period was 26 months (15~40). The mean age was 48 years old. Injury mechanism was composed of 6 cases of traffic accident and 6 cases of fall down. 8 persons were man. We investigated the union time, degree of neck-shaft angle change, amount of sliding of compression hip screw, complications, functional and clinical results. Results: 10 cases were united and the mean union time were 5 months (3~8). The mean neck-shaft angle change was 3.5 degrees (0~12). The amount of sliding of compression hip screw was 8.9 mm (2~24). There were six coxa vara, six leg due to coxa vara shortening, two nonunion, and one superficial infection. Unsatisfactory results of Jensen's social function score and Parker and Palmer's mobility score were studied. Conclusion: The results of treatment of reverse oblique trochanteric fractures with compression hip screw were relatively unsatisfied.

• Clinics in Shoulder and Elbow
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• 제6권1호
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• pp.44-49
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• 2003

Purpose: Many different operative technique of mid-shaft clavicle fracture have been reported. The aim of this prospective study was to compare the results of anterior or anterior-inferior plating with superior plating on the acute mid-shaft fracture of clavicle Materials and Methods: From February1997 to February 2002, thirty-eight consecutive open reduction and internal fixation with reconstruction plates were performed in thirty-eight patients. from August 1999, anterior or anterior-inferior plating was mainly used, prospectively. The duration of follow-up averaged 17 months (range,23 to 43 months). The mean age was 38 years old (range,21 to 57 years old) on anterior or anterior-inferior plating group and 35 years old (range,24 to 55 years old) on superior plating group. The physician progress note, VAS patient complement score, Roentgenogram and ASES score was evaluated. Results: Four patients were lost to follow-up. There was no statistical difference on mean radiological bone union time （8.7 weeks vs. 8.6 weeks) and ASES score (92 vs 94) at inferior and superior plating groups (P > 0.05). VAS patient complement score was very good or excellent on anterior or anterior-inferior group, average score was 1.1 (ranger,0 to 2) compare with superior plating group (P < 0.05). There were two cases of infection, 1 case of failed fixation on superior plating group and 1 case of delayed union on anterior inferior plating group. Conclusion: Anterior inferior plating on acute clavicle midshaft fracture results in excellent patient complement score compare with conventional superior reconstruction plate.

• Clinics in Shoulder and Elbow
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• 제20권2호
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• pp.90-94
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• 2017

Background: Proximal humerus fracture is considered to be the third most common fracture for patients aged 65 years or older. Conservative treatment has been known to treat most of humerus fracture. However, fractures with severe displacement or dislocation may require surgical treatment. Intramedullary fibular allograft with a locking plate is frequently used in patients accompanying medial metaphyseal disruption. In this study, author intends to evaluate clinical and imaging results based on patients who underwent surgical treatment using fibular allograft with a locking plate. Methods: This study is conducted prospectively at Wonju Severance Christian Hospital, targeting patients who previously underwent surgical treatment using open reduction and intramedullary fibular allograft with a locking plate between 2011 and 2015. A total of 26 patients were evaluated on the following: postoperational clinical assessment measuring Constant score, American Shoulder and Elbow Society (ASES) score, and the Disabilities of the Arm, Shoulder and Hand (DASH) score. Postoperational imaging assessments are evaluated via measuring the neck-shaft angle. The study subject were Neer classification type 3, 4 proximal humerus fracture cases with disrupted medial hinge and having cortical comminution in the region of the surgical neck. Results: The average period of progression was 22.5 months, and the average age of patients was 72.6 years. At the final follow-up, the average Constant, average ASES, and average DASH scores were 80.1, 78.5, and 20.6 respectively. The average neck-shaft angle was $127.5^{\circ}$. Conclusions: In conclusion, fibular allograft augmentation with a locking plate showed satisfying results in both clinical and imaging studies.

• 한국정밀공학회지
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• 제24권3호
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• pp.84-90
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• 2007

As a result of vehicle maintenance of rocker arm shaft for 4-cylinder SOHC engine, failure stress analysis of rocker arm shaft is needed. Because more than 30% of vehicles investigated have been fractured. Failure stress analysis is classified into an naked eyes, microscope, striation and X-ray fractography etc. Failure stress analysis by using striation is already established technology as means for seeking cause of fracture. But, although it is well known that striation spacing corresponds to the crack growth rate da/dN, it is not possible to determine ${\sigma}_{max}\;and\;{\sigma}_{min}$ under service loading only from striation spacing. This is because the value of striation spacing is influenced not only by ${\Delta}K$ but also by the stress ratio R. In the present paper, we determine the stress ratio using orthogonal array and ANOVA, and propose a prediction method of failure stress which is combined with FEM and striation.

• Journal of Trauma and Injury
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• 제18권1호
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• pp.41-46
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• 2005

Background: We evaluated the clinical and the radiological results of treatment for humeral shaft fractures by using an antegrade intramedullary nail. Methods: Thirty-nine (39) cases of humeral shaft fractures treated with antegrade intramedullary nail were evaluated. Bone union was evaluated with simple radiographic findings, and a functional evaluation was done using the American Shoulder and Elbow Surgeons (ASES) score. Results: The average duration until union was 14.1 weeks. On the functional evaluation using the ASES score, 15 cases were excellent, 19 cases good, 3 cases fair, and 2 cases poor. Conclusion: We conclude that antegrade intramedullary nailing has a good clinical and radiological result for treatment of humeral shaft fractures.