• Archives of Plastic Surgery
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• 제38권6호
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• pp.851-860
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• 2011

Purpose: Reduction by simply assembling bones is recognized as treatment for a zygoma fracture. However, in patients who originally had a protruding zygoma, the fractured parts look like malarplasty after the edema subsides, giving a soft impression which patients notice. Thus, we created symmetry through simultaneous contralateral malar reduction in a unilateral zygoma fracture. Methods: In this study, the patients who had surgery between July, 2008 and December, 2009 with admission were object. In 76 patients with a zygoma fracture, the patients with bilateral zygoma fractures were excluded. Among 48 patients who had a reduction only after a unilateral zygoma fracture, the patients hoping for a reduction of their rough protruding zygoma were analyzed with front cephalometry. The study progressed on 22 patients who had simultaneous contralateral malar reduction in a unilateral zygoma fracture with consent. After fixing the fracture, we did a straight zygoma osteotomy through a 1.5 cm intraoral incision. After that, we created symmetry with a special ruler and fixed the broken zygomatic arch with a screw and plate. We evaluated the facial index and satisfaction with a statistical analysis before and after the surgery. Results: In 22 patients, there was no reoperation except for 1 patient who had a zygoma fracture. None of the patients were treated for infection or hematoma. Two patients complained of paresthesia after the malar reduction operation, but this subsided in 4 months. Most of them were satisfied with the malar reduction, especially the women, and we obtained a better mid facial contour with decreased facial width ($p$ <0.05). Conclusion: Existing zygoma fracture surgery focuses on anatomical reduction. However, we need to have a cosmetic viewpoint in fractures as interests of face contour arise. Thus, contralateral malar reduction got a 4.7 (range 0~5) from patients who had malar reduction surgery in our hospital. Although adjusting to all zygoma fractures has limitations, it can be a new method in zygoma fractures when there are limited indications of protruding zygoma and careful attention is given to patients' high demands.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권4호
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• pp.1-11
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• 2003

압축력의 변화에 따른 균열 간극변화 양상을 측정하고 간극변화와 수리전도도와의 관계를 파악하기 위해 이 연구에서는 다섯 단계의 수직 일축압축력을 균열면에 연속적으로 가하면서 고해상도의 공초점 레이저 스캔 현미경 (confocal laser scanning microscope; CLSM)을 이용하여 간극의 크기를 측정하고 디지털 이미지를 획득하였다. 기존의 연구들과는 달리 이 연구의 측정방법은 압력변화에 대한 동일시료 간극의 반응을 연속적으로 파악할 수 있는 점이 특징이다. 측정결과는 간극크기가 일정하지 않은 불평탄한 균열형태를 매우 잘 나타내었다. 균열 조도(roughness)로 인해 압력에 따른 간극 변화량은 일정하지 않고 부분마다 다름을 보였다. 각 압력단계에서 간극변화에 따른 투수성 변화양상을 파악하고자 실내투수시험을 병행하여 실시한 결과, 각 압력단계에서의 투수성 변화도 일정한 감소율을 나타내지 않고 간극 변화율이 크더라도 투수율은 오히려 작은 경우도 관찰되었다. 현미경을 통해 측정한 물리적 간극과 실제 유체유동 경로가 되는 수리간극의 크기 차이를 파악하기 위해 계산을 한 결과, 미미한 갈이지만 물리적 간극보다 작은 크기의 수리간극이 구해졌다. 또한, 실내투수시험 결과를 이용하여 구한 투수계수는 삼승법칙을 따르지 않는 것으로 드러났으며, 이러한 사실들은 균열 양쪽이 서로 평행하지 않고 불평탄한 양상을 가짐을 의미하는 것으로서, 현미경을 통해 직접 관찰한 간극양상과 잘 일치하는 것이다.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.714-721
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• 2018

본 논문은 강교량 거더, 교각, 선박이나 대형 저장 시설 등 주요 구조 부재에 활용되는 곡판 및 강관을 효과적으로 보강하는 방안에 관한 것이다. 최근 연구에서 압축을 받는 평판이 종방향 보강재의 단면회전강성에 의해 국부좌굴강도가 향상되는 특징을 정량적으로 분석하였고, 폐단면리브 단면회전강성과의 상관관계를 규명한 바 있다. 본 논문에서는 곡판에 대해 이와 같은 효과를 정량적으로 검토하고자 한다. 일축압축이 재하된 경우에 폐단면리브로 보강된 두께방향으로 곡률을 가지는 곡판의 좌굴거동을 살펴보기 위해 범용 구조해석 프로그램인 ABAQUS를 이용하여 3차원 유한요소해석 모델을 생성하였다. 이를 통해 좌굴거동에 대한 수치해석을 수행하였으며, 영향인자에 대한 변수해석적 연구를 수행하여 좌굴응력과 좌굴모드의 변동특성을 정량적으로 평가하였다. 폐단면리브 단면회전강성의 구속효과로 인한 좌굴강도 증가효과와 판의 곡률에 따른 좌굴강도 계수를 고려하여 좌굴강도를 추정하는 방법론을 이론적으로 제안하였다. 제안된 공식은 유한요소해석 결과와 비교하여 서로 유의미성이 검토되었다. 또한 평판에서와 마찬가지로 일축압축 상태에서 폐단면리브의 단면강성에의해 부여되는 양측단 회전강성의 증가로 인해 곡판의 국부좌굴강도가 이에 비례하여 증가하였고, 양측단에서 회전이 고정된 곡판의 좌굴강도에 수렴하는 경향을 확인하였다.

• Clinics in Shoulder and Elbow
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• 제13권2호
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• pp.260-265
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• 2010

목적: 척골 구상돌기 골절에 대해 내측 접근법을 통한 전방 금속판 고정술이 시행된 2예의 임상적 결과를 보고하고자 한다. 대상 및 방법: 수술적 치료가 필요한 척골 구상돌기 골절 2예에서 척 수근 굴근 양 두 사이로 접근하는 내측 접근법을 통해 2.4 mm 잠김 압박 금속판 (Compact Hand set$^{(R)}$, Synthes, Switzerland)을 이용한 전방 금속판 고정술이 시행되었다. 추시 기간은 각각 14개월, 17개월이었으며, Mayo Elbow Performance Score로 임상적 결과를 판정하였다. 결과: Mayo Elbow Performance Score는 각각 95점 (증례 1), 100점 (증례 2)이었다. 능동적 주관절 운동 범위는 $5^{\circ}{\sim}120^{\circ}$, $0^{\circ}{\sim}130^{\circ}$이었고, 회내 및 회외 영역은 모두 회복되었다. 결론: 내측 접근법을 통한 전방 금속판 고정술은 척골 구상돌기 골절에서 견고한 고정 및 조기 관절운동을 가능하게 하여 우수한 치료 결과를 얻을 수 있었다.

• Clinics in Shoulder and Elbow
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• 제8권2호
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• pp.97-104
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• 2005

Purpose: To report the results of surgical treatment of comminuted fractures of distal humerus and to identify factors that affect the results. Materials and Methods: Thirty-two patients who were treated with open reduction and internal fixation for comminuted fracture of distal humerus were enrolled. According to the AO classification, A2.3 was 1 case, A3.2, 2 cases, A3.3, 8 cases, B1.3, 1 case, B2.3, 1 case, C2.2, 5 cases, C2.3, 4 cases, C3.2, 3 cases and C3.3, 7 cases. As fixation technique, 17 cases were fixed by double plates, 4 cases by only K-wires, 4 cases by only screws, 3 cases by K-wires and screws and 4 cases by one plate and screws. The mean age at the time of the operation was 49 years(range, $19{\sim}77$ years). The mean follow-up period was 16 months(range, $8{\sim}51$ months). Results: At the last follow-up, the mean maximum flexion was $116.4^{\circ}\;(range,\;85{\sim}140^{\circ})$ and the mean loss of terminal extension was $11.8^{\circ}\;(range,\;0{\sim}40^{\circ})$. The average Mayo elbow performance score was $91.4^{\circ}\;(range,\;55{\sim}100^{\circ})$. Overall 29 cases(91%) showed good to excellent results. The mean range of motion of extraarticular and intraarticular fracture group was $105.5^{\circ}\;(range,\;65{\sim}140^{\circ})$ and $104^{\circ}\;(range,\;55{\sim}140^{\circ})$, respectively. The average elbow score of both groups was$93^{\circ}\;(range,\;70{\sim}100^{\circ})$ and $90.7^{\circ}\;(range,\;55{\sim}100^{\circ})$. Over 90% showed more than good results. 30 cases(94%) showed complete bony union but two cases, nonunion. One case of the nonunion cases underwent replating with bone graft as revision surgery and total elbow arthroplasty was performed in the other case. At the last follow-up, 27 patients(84.4%) showed subjective satisfaction. Conclusion: Open reduction and internal fixation with appropriate surgical technique for comminuted fractures of distal humerus showed good results, which were not affected by age at the time of operation, fixation methods and anterior transposition of the ulnar nerve. Transolecranon approach may be considered as good choice for intraarticular comminuted fractures of distal humerus.

• 한국임상수의학회지
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• 제29권5호
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• pp.412-415
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• 2012

1년령의 중성화된 수컷 요크셔테리어와 7년령의 암컷 푸들이 골절의 지연유합으로 내원하였다. 요크셔테리어의 경우 오른쪽 요골과 척골의 원위부가 골절되었고, 푸들의 경우 왼쪽 경골과 비골의 원위부가 골절되었다. 두 환자에서 신체검사 및 방사선검사를 통해 골절의 유합이 지연되고 있음을 확인하였다. 골절부는 금속판 및 나사못으로 고정시키고 자가해면질골을 골절 틈새에 이식하였다. 또한 빠른 골유합을 위해 $20{\mu}g$의 rh-BMP 2 가 포함된 matrigel을 골절부에 주입하였다. 수술 후 방사선검사를 통해 골절부의 치유 상태를 확인하였다. 장기간의 방사선검사에서 두 마리 모두 빠른 골유합을 보였다. 첫 증례에서는 방사선사진상에서 2주째에 요골과 척골 골절 틈새에 골밀도가 증가하였다. 20주째에는 골절선이 더 이상 관찰되지 않았으며, 정상 외관을 회복하였다. 두 번째 증례에서는 방사선사진상에서 11주째에 골절 치유가 진행되고 있음이 확인되었다. 이 두 증례 모두 예상한 것보다 골절의 치유가 빠르게 일어났다. 따라서 rh-BMP 2와 matrigel은 지연유합된 골절의 치유를 촉진하는데 효과가 있다고 생각된다.

• 대한디지털의료영상학회논문지
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• 제14권2호
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• pp.1-8
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• 2012

Purpose : We aim at presenting the optimum radiologic factor through the evaluation of dose variation and of image quality through the use of a grid in Humerus examination and the change of dose because of the change of radiologic factor. Materials and Methods : We divided it in 3 cases: when using a grid or not and when using IP(Image Plate) in a digital system. Also, as fixing kVp to 70kVp it changed mAs, and fixing mAs to 10 it changed kVp, we put up resolution chart and Burger rose phantom on the acrylic phantom of 7cm (the same level of Humerus) to evaluate the dose and image. We used Image J program to evaluate the quantitative resolution of the obtained image, and made the qualitative evaluation and statistical analysis of the image saved in PACS for 20 radiologic technologist with more than 10 years of experience in order of evaluate its contrast. We used SPSS10(SPSS Inc. Chicago, Illinois) for statistical analysis. Results : We observed the analytic result of resolution by the change of kVp that it was $4.539dGycm^2$ in 60kVp and $757.472dGycm^2$ in 75kVp, which increased about 64.6% of dose, while for the resolution it had the pixel value 30.7% better with 851 in 60kVp than 651 in 75kVp. Also, we analyzed the result of resolution by the change of mAs that it was $3.106dGycm^2$ in 5mAs, and $12.470dGycm^2$ in 20mAs, which increased about 400% of dose, while for the resolution DR had 678 in 5mAs, and 724 in 20mAs that increased about 6.8% of resolution. We made the qualitative evaluation of contrast by the change of kVp that DR showed the higher quality than CR, but the contrast by the change of kVp had no special different at the moment of visual evaluation, nor statistically significant difference(P>0.05). We observed the qualitative evaluation of contraste by the change of mAs that the contrast increased as DR increased mAs, and had statistically significant difference(P<0.05). On the other hand, CR had no significant difference for more than 10mAs nor statistically significant difference(P>0.05). Conclusion : In case of some patients with radiographic exposure by the repeated examination such as emergent patient or Follow up patient, they are considered to try to limit the use of a grid, to set kVp under 65kVp in fixed mode, to select less than 10mAs and to reduce the possibility of patient being bombed.

• Design & Manufacturing
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• 제14권3호
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• pp.8-16
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• 2020

In this study, the vibration signal of the mold was measured and analyzed to monitoring the process time and characteristics during injection molding. A 5 inch light guide plate mold was used to injection molding and the vibration signal was measured by MPU6050 acceleration sensor module attached the surface of fixed mold base. Conditions except for injection speed and packing pressure were set to the same value and the change of the vibration signal of the mold according to injection speed and packing pressure was analyzed. As a result, the vibration signal had a large change at three points: "Injection start", "V/P switchover", and "Packing end". The time difference between "injection start" and "V/P switchover" means the injection time in the injection molding process, and the time difference between "V/P switchover" and "Packing end" means the packing time. When the injection time and packing time obtained from the vibration signal of the mold are compared with the time recorded in the injection molding machine, the error of the injection time was 2.19±0.69% and the error of the packing time was 1.39±0.83%, which was the same level as the actual value. Additionally, the amplitude at the time of "injection start" increased as the injection speed increased. In "V/P switchover", the amplitude tended to be proportional to the pressure difference between the maximum injection pressure and the packing pressure and the amplitude at the "packing end" tended to the pressure difference between the packing pressure and the back pressure. Therefore, based on the result of this study, the injection time and packing time of each cycle can be monitored by measuring the vibration signal of the mold. Also, it was confirmed that the level and trend of process variables such as the injection speed, maximum injection pressure, and packing pressure can be evaluated as the change of the mold vibration during injection molding.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권6호
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• pp.398-403
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• 2012

Purpose: Mandible resection and discontinuity defect created lead to aesthetic and functional problems. The iliac crest bone graft exhibits relative ease for bone harvesting, possibility of two team approach, ability to close the wound primarily, large amount of corticocancellous bone and relatively few complications. Whereas the use of free vascularized flaps has donor site morbidity and worse-fitting bone contour, the use of nonvascularized iliac bone graft has advantages in the operation time and patients' recovery time. So, nonvascularized iliac bone graft could be an attractive option. Methods: Twenty-one patients (M:F=1:1.1) underwent iliac crest bone harvesting for reconstruction of mandibular discontinuity defect (mean length : $61.6{\pm}17.8$ mm), from May 2005 to October 2011 at the Department of Oral and Maxillofacial Surgery in Kyungpook National University. The average age was $44.1{\pm}16.4$ years and the mean follow up periods was $28.2{\pm}22.7$ months. Bone resorption rate, according to age, sex, primary lesion, location and distance of defect, type of fixation plate, time of graft and pre-operative radiation therapy, were measured in each patient. Results: The mean bone resorption rate was $16.1{\pm}9.0%$. Bone resorption rate was significantly increased in mandibular defect that is over 6 cm in size (P=0.015, P<0.05) and the cases treated pre-operative radiation therapy (P=0.017, P<0.05). All was successfully fixed and maintained for the long-term follow-up. There were a few donor site complications and almost all patients were shown favorable outcome without severe bone resorption in this study. Conclusion: The nonvascularized iliac bone graft seems to be a reasonably reliable treatment option for reconstruction of mandibular discontinuity defects.

• 한국임상수의학회지
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• 제31권6호
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• pp.527-530
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• 2014

7살 중성화된 수컷 한국집 고양이가 6개월동안 지속된 변비를 주증으로 본원에 내원하였다. 직장검사에서 골반강의 우측 외측부분의 좁아짐을 보였고, 방사선검사에서는 골반골절의 부정유합으로 인한 골반강의 협착을 확인할 수 있었다. 골반강 직경 비율은 0.68이었다. 직장검사와 방사선검사를 기반으로 골반강 협착으로 인한 변비로 진단하였다. 그래서 골반결합을 절골하여 골반강 확장술을 시행하였고 이를 용이하게 하기 위하여 장골 절골술도 함께 시행하였다. 확장된 골반강을 유지하기 위하여 골반결합 사이에 폴리메칠메타크릴레이트를 성형하여 구조물로 삽입하였다. 절골 한 장골은 뼈판과 나사를 이용하여 다시 고정시켜주었다. 방사선 검사에서 술 후 골반강 직경 비율은 0.91로 증가했음을 알 수 있었다. 술 후 처치로는 항생제, 진통소염제, 락툴로오스경구제 투여와 함께 수액요법을 시행하였다. 환자는 골반강 확장술 후 일주일부터 정상적인 배변을 보였고, 그 이후 6개월동안 재발은 없었다. 이 증례를 바탕으로 골반강 확장술은 골반골절의 부정유합으로 인한 골반강 협착에 따라 발생한 변비에서 유용한 치료법으로 사료된다.