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반월형 근위 중족골 절골술에 대한 보강적 축성 K-강선 고정술 : 생체역학적 연구 (Additional axial K-wire Fixation for Proximal Crescentic Metatarsal Osteotomy : A Biomechanical Study)

  • 정홍근;김유진
    • 대한족부족관절학회지
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    • 제7권2호
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    • pp.151-156
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    • 2003
  • Purpose: Proximal crescentic metatarsal osteotomy(PMO) is one of the most common procedures for correcting moderate to severe degree hallux valgus deformity. Although screw fixation is used for osteotomy site stability, loss of reduction can occur. The purpose of this study is to compare the sagittal plane stability of the conventional crescentic PMO fixed with a single screw with that of the crescentic PMO fixed with 1 screw and 2 supplemental K -wires. Material and Methods: Ten matched pairs of cadaveric foot specimens were used for the proximal crescentic metatarsal osteotomy. For one foot specimen of each pair, crescentic osteotomy was fixed with 4mm long threaded cannulated screw, while the matched pair was prepared by adding two axial 1.6mm K-wires to the conventionally fixed 4mm screw. The extensometer was used to measure the osteotomy gap as the metatarsal head was loaded continuously until failure using a servohydraulic MTS Mini Bionix test frame. The strength of fixation was normalized with the bone mineral density (BMD) of the paired specimen $(N{\times}cm^{2}/gm)$, Result: The average strength of the crescentic PMO with axial K-wire fixation ($458.8cm^{2}/gm$, S.D. 434.3) was significantly higher than the standard crescentic PMO ($367.5cm^{2}/gm$, S.D. 397,9) (p=0.05). Conclusion: Supplemental fixation with two axial K-wires can be added to the crescentic PMO to enhance the initial fixation stability to prevent the loss of reduction or dorsal malunion.

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영주지방에 분포하는 사상충 자충에 대한 형태학적 연구 (Morphological Study of Microfilariae Found in the Area of Yongju-Gun)

  • 김훈수
    • 한국동물학회지
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    • 제8권1호
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    • pp.11-14
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    • 1965
  • The object to this study is to identify the genus and species of the microfilariae which were recently found in the area of Youngju-Gun. THe identification of the microfilariae was made on the morphologicla aspects. 1. Blood samples were collected through vena punction from known microfilariae carriers living in the newly confirmed filaria endemic area of Youngju0Gun in Jyongsang Pukdo Province. Youngju-Gun is located in the mountainous central part of Korean Peninsula. 2. The following fixation and staining techniques were applied. (1) Fixation by drying in the air, followed by staining with Azeo or Giemsa. (2) Knott's fixation method (2% formalin), followed by staining with Azur II. 3. A comparative study of the body length of the microfilariae after different fixation and staining techniques were applied. (1) Knott's fixation method followed by staining with Azur II : average body length found was 28.4$\mu$. (2) Dry fixation followed by staining with Giemsa : average body length found was 209.4$\mu$. (3) Dry fixation followed by staining with Azeo : average body length found was 205.4$\mu$. 4. The locations of the different body cells were measured in 60 individuals of microfilariae in the wet preparation fixed by Knott's method and stained with Azur II. The distance of the different body cells to cephalic apex of microfilariae was measured and calculated as a percentage of the total body length. The average results are as follows : BNC , 3.04% ; N, 22.74%, EP, 31.4% ; EC, 37.77%, G1 cell , 67.94%; G2 cell, 73.54% : G3 cell , 75.55% ; G4 cell, 77.65% ; AP, 82.02%%. 5. As a result of the above findings the microfilariae found in the above mentioned area could be identified as Brugia malai(BRUG, 1927) BUCKLEY, 1960.

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Xenograft Failure of Pulmonary Valved Conduit Cross-linked with Glutaraldehyde or Not Cross-linked in a Pig to Goat Implantation Model

  • Kim, Dong Jin;Kim, Yong Jin;Kim, Woong-Han;Kim, Soo-Hwan
    • Journal of Chest Surgery
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    • 제45권5호
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    • pp.287-294
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    • 2012
  • Background: Biologic valved grafts are important in cardiac surgery, and although several types of graft are currently available, most commercial xenografts tend to cause early disfiguration due to intimal proliferation and calcification. We studied the graft failure patterns on non-fixed and glutaraldehyde-fixed pulmonary xenograft in vivo animal experiment. Materials and Methods: Pulmonary valved conduits were obtained from the right ventricular outflow tract of eleven miniature pigs. The grafts were subjected to 2 different preservation methods; with or without glutaraldehyde fixation: glutaraldehyde fixation (n=7) and non-glutaraldehyde fixation (n=4). The processed explanted pulmonary valved grafts of miniature pig were then transplanted into eleven goats. Calcium quantization was achieved in all of the explanted xenograft, hemodynamic, histopathologic and radiologic evaluations were performed in the graft which the transplantation period was over 300 days (n=7). Results: Grafts treated with glutaraldehyde fixation had more calcification and conduit obstruction in mid-term period. Calcium deposition also appeared much higher in the glutaraldehyde treated graft compared to the non-glutaraldehyde treated graft (p<0.05). Conclusion: The present study suggests that xenografts prepared using glutaraldehyde fixation alone appeared to have severe calcification compared to the findings of non-glutaraldehyde treated xenografts and to be managed with proper anticalcification treatment and novel preservation methods. This experiment gives the useful basic chemical, histologic data of xenograft failure model with calcification for further animal study.

하악 시상골 절단술 후 고정 방법에 따른 회귀 성향에 대한 비교 연구 (Comparative Study of Skeletal Relapse According to the Fixation Method after BSSRO for Mandibular Setback.)

  • 배진오;이동근;오승환;신기영;장관식
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제22권2호
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    • pp.184-190
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    • 2000
  • Objective : To compare two different methods of rigid fixation in postoperative stability after mandibular setback. Material and Methods : 28 patients with Class III malocclusion were treated by bilateral sagittal split ramus osteotomy(BSSRO) and mandibular setback were selected for this study. Group A(n=14) had the bone segments fixed with monocortical miniplate on the lateral side of the mandibular body and Group B(n=14) had three noncompressive bicortical screw inserted at the genial area through a transcutaneous approach. Cephalograms were taken preoperatively, postoperatively within 1 weeks and at a follow-up period (mean 8.9 months after surgery) and the amount of setback and postoperative change were measured. Results : Postoperative relapse between two groups was minimal in setback of the mandible. Statistical analysis showed no significant difference in postoperative relapse. Conclusion : This study suggests that both methods of skeletal fixation investigated give comparable postoperative stability and their use in mandibular setback appears to be a fairly stable clinical procedure .

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Kirschner Wire Fixation for the Treatment of Comminuted Zygomatic Fractures

  • Kang, Dai-Hun;Jung, Dong-Woo;Kim, Yong-Ha;Kim, Tae-Gon;Lee, JunHo;Chung, Kyu Jin
    • 대한두개안면성형외과학회지
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    • 제16권3호
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    • pp.119-124
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    • 2015
  • Background: The Kirschner wire (K-wire) technique allows stable fixation of bone fragments without periosteal dissection, which often lead to bone segment scattering and loss. The authors used the K-wire fixation to simplify the treatment of laborious comminuted zygomatic bone fracture and report outcomes following the operation. Methods: A single-institution retrospective review was performed for all patients with comminuted zygomatic bone fractures between January 2010 and December 2013. In each patient, the zygoma was reduced and fixed with K-wire, which was drilled from the cheek bone and into the contralateral nasal cavity. For severely displaced fractures, the zygomaticofrontal suture was first fixated with a microplate and the K-wire was used to increase the stability of fixation. Each wire was removed approximately 4 weeks after surgery. Surgical outcomes were evaluated for malar eminence, cheek symmetry, K-wire site scar, and complications (based on a 4-point scale from 0 to 3, where 0 point is 'poor' and 3 points is 'excellent'). Results: The review identified 25 patients meeting inclusion criteria (21 men and 4 women). The mean age was 52 years (range, 15-73 years). The mean follow up duration was 6.2 months. The mean operation time was 21 minutes for K-wire alone (n=7) and 52 minutes for K-wire and plate fixation (n=18). Patients who had received K-wire only fixation had severe underlying diseases or accompanying injuries. The mean postoperative evaluation scores were 2.8 for malar contour and 2.7 for K-wire site scars. The mean patient satisfaction was 2.7. There was one case of inflammation due to the K-wire. Conclusion: The use of K-wire technique was associated with high patient satisfaction in our review. K-wire fixation technique is useful in patient who require reduction of zygomatic bone fractures in a short operating time.

Three-dimensional finite element analysis of the stress distribution and displacement in different fixation methods of bilateral sagittal split ramus osteotomy

  • Yun, Kyoung In;Cho, Young-Gyu;Lee, Jong-Min;Park, Yoon-Hee;Park, Myung-Kyun;Park, Je Uk
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제38권5호
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    • pp.271-275
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    • 2012
  • Objectives: This study evaluated a range of fixation methods to determine which is best for the postoperative stabilization of a mandibular osteotomy using three-dimensional finite element analysis of the stress distribution on the plate, screw and surrounding bone and displacement of the lower incisors. Materials and Methods: The model was generated using the synthetic skull scan data, and the surface model was changed to a solid model using software. Bilateral sagittal split ramus osteotomy was performed using the program, and 8 different types of fixation methods were evaluated. A vertical load of 10 N was applied to the occlusal surface of the first molar. Results: In the case of bicortical screws, von-Mises stress on the screws and screw hole and deflection of the lower central incisor were minimal in type 2 (inverted L pattern with 3 bicortical repositioning screws). In the case of plates, von-Mises stress was minimal in type 8 (fixation 5 mm above the inferior border of the mandible with 1 metal plate and 4 monocortical screws), and deflection of the lower central incisor was minimal in types 6 (fixation 5 mm below the superior border of the mandible with 1 metal plate and 4 monocortical screws) and 7 (fixation 12 mm below the superior border of the mandible with 1 metal plate and 4 monocortical screws). Conclusion: Types 2 and 6 fixation methods provide better stability than the others.

Effect of cigarette smoking on the maintenance of reduction after treatment of acute acromioclavicular joint dislocation with hook plate fixation

  • Jee-Hoon Choi;Yong-Min Chun;Tae-Hwan Yoon
    • Clinics in Shoulder and Elbow
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    • 제26권4호
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    • pp.373-379
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    • 2023
  • Background: The purpose of this study was to determine the association between smoking and clinical outcomes of hook plate fixation for acute acromioclavicular (AC) joint injuries. Methods: This study retrospectively investigated 82 patients who underwent hook plate fixation for acute AC joint dislocation between March 2014 to June 2022. The patients were grouped by smoking status, with 49 in group N (nonsmokers) and 33 in group S (smokers). Functional scores and active range of motion were compared among the groups at the 1-year follow-up. Coracoclavicular distance (CCD) was measured, and difference with the uninjured side was compared at initial injury and 6 months after implant removal. Results: No significant differences were observed between the two groups in demographic factors such as age and sex, as well as parameters related to initial injury status, which included time from injury to surgery, the preoperative CCD difference value, and the Rockwood classification. However, the postoperative CCD difference was significantly higher in group S (3.1±2.6 mm) compared to group N (1.7±2.4 mm). Multivariate regression analysis indicated that smoking and the preoperative CCD difference independently contributed to an increase in the postoperative CCD difference. Despite the radiographic differences, the postoperative clinical outcome scores and active range of motion measurements were comparable between the groups. Conclusions: Smoking had a detrimental impact on ligament healing after hook plate fixation for acute AC joint dislocations. This finding emphasizes the importance of smoking cessation to optimize reduction maintenance after AC joint injury. Level of evidence: III.

비탄력 고정식 벨트가 노인 여성의 균형능력과 낙상예방에 미치는 영향 (The Effect of Application of a Non-Elastic Fixation Belt on the Balance Ability and Fall Prevention in Elderly Women)

  • 이장태;천승철
    • 한국산학기술학회논문지
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    • 제18권2호
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    • pp.398-404
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    • 2017
  • 본 연구의 목적은 노인 여성의 약화된 천장관절 안정화를 위하여 비탄력 고정식 벨트를 적용하여 균형 능력과 낙상예방에 미치는 영향을 알아보고자 하였다. 노인 여성들은 출산과 폐경으로 천장관절의 약화 및 골반 주위근육들의 약화로 인하여 균형능력의 감소와 낙상위험률이 증가된다. 그러나 이와 관련된 연구는 불충분하다. 연구 대상자들은 실험군과 대조군으로 각각 20명씩 무작위로 배정하였으며, 비탄력 고정식 벨트를 실험군에게 적용한 후 균형 측정기를 사용하여 균형능력과 낙상 위험률을 평가하였다. 또한 비탄력 고정식 벨트를 적용한 실험군에서 하복부근육의 근두께를 초음파기기를 사용하여 실험 전후에 측정하였다. 통계방법은 연구대상자의 일반적 특성을 위하여 독립 t-검정, 균형 및 낙상지수를 위하여 $2{\times}2$ 반복 측정 분산분석 및 근두께를 위하여 짝비교 t-검정을 사용하였다. 두 그룹의 교호작용 효과는 안정성 지수(F1,38=47.24, p=0.001), 퓨리에 지수(F1,38=88.83, p=0.001), 체중분포 지수(F1,38=50.21, p=0.001) 및 낙상 지수(F1,38=21.59, p=0.001)에서 모두 통계적으로 유의하게 나타났다. 또한 비탄력 고정식 벨트를 적용한 결과 실험 후 복횡근(p=0.001)과 내복사근(p=0.001)의 근두께는 통계적으로 유의하게 증가하였다. 노인 여성들의 약화된 천장관절의 강화 및 안정화 방법으로 비탄력 고정식 벨트는 균형 및 낙상 예방에 긍정적이며 용이성, 보편성 및 경제적으로 효과적임을 알 수 있었다.

Introduction, Development, and Characterization of Supernodulating Soybean Mutant -Nitrate Inhibition of Nodulation and Nitrogen Fixation in Supernodulating Soybean Mutant-

  • Lee, Hong-Suk;Lee, Suk-Ha
    • 한국작물학회지
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    • 제43권1호
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    • pp.23-27
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    • 1998
  • Inhibition of nodule formation and nitrogen fixation by soil nitrogen, primarily nitrate, is well known in legume plants. The present study was undertaken to evaluate the effect of ${NO_3}^-$ on the nodulation, nitrogenase activity, and growth of supernodulating soybean mutant and its wild type. A greenhouse study was conducted to compare two of supernodulating mutants, 'SS2-2' and 'nts 382', with the normal nodulating cultivar 'Sinpaldalkong 2' when grown in a 1-l styroform cup filled with sand, and fertilized with five levels of ${NO_3}^-$ (0, 2, 4, 8, and 12 mM). During the growth period, each plant was supplied two or three times a week with 50 mL of nutrient solution. Supernodulating soybean mutants, SS2-2 and nts 382, showed more nodules and nodule mass, and greater $C_2\;H_2$ activity than the wild type, Sinpaldalkong 2, regardless of the level of exogeneous nitrogen supply. On the other hand, total dry weight of SS2-2 mutant, which was smaller than Sinpaldalkong 2, did not respond to the various ${NO_3}^-$-N levels. This suggested that supernodulating SS2-2 mutant could maintain fairly high total dry weight at the low ${NO_3}^-$-N level, even in the absence of exogeneous ${NO_3}^-$-N in the nutrient solution. From the reduced top growth and high nitrogen fixing ability of supernodulating mutants, it was surmised that supernodulating mutant could potentially protect agricultural environments from pollution through the reduction in nitrogen fertilization as well as maintain fairly high yield with increasing planting density.

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