• Structural Engineering and Mechanics
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• 제9권6호
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• pp.541-555
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• 2000

Pultruded cross-sections are always thin-walled due to constraints in the manufacturing process. Thus, the buckling strength determines the overall strength of the member. The elastic buckling of pultruded angle sections subjected to direct compression is studied. The lateral-torsional buckling, very likely to appear in thin-walled cross-sections, is investigated. Plate theory is used to allow for cross-sectional distortion. Shear effects and bending-twisting coupling are accounted for in the analysis because of their significant role. A simplified approach for determining the maximum load of equal leg angle sections under compression is presented. The analytical results obtained in this study are compared to the manufacturer's design guidelines for compression members as well as with the design specifications for steel structural members. Experimental results are obtained for various length specimens of pultruded angle sections. The results presented in this paper correspond to actual pultruded equal leg angle sections being used in civil engineering structures.

• 대한두개안면성형외과학회지
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• 제17권4호
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• pp.206-210
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• 2016

Background: Zygoma is a major buttress of the midfacial skeleton, which is frequently injured because of its prominent location. Zygoma fractures are classified according to Knight and North based on the direction of anatomic displacement and the pattern created by the fracture. In zygomaticomaxillary complex (ZMC) fracture many incisions (lateral eyebrow, lateral upper blepharoplasty, transconjunctival, subciliary, subtarsal, intraoral, direct percutaneous approach) are useful. We reviewed various approaches for the treatment of ZMC fractures and discussed about incisions and fixation methods. Methods: A retrospective review was conducted of patients with ZMC fracture at a single institution from January 2005 to December 2014. Patients with single zygomatic arch fracture were excluded. Results: The identified 694 patients who were admitted for zygomatic fractures from which 192 patients with simple arch fractures were excluded. The remaining 502 patients consisted of 439 males and 63 females, and total 532 zygomatic bone was operated. Orbital fracture was the most common associated fracture. According to the Knight and North classification the most frequent fracture was Group IV. Most fractures were fixated at two points (73%). Conclusion: We reviewed our cases over 10 years according to fracture type and fixation methods. In conclusion, minimal incision, familiar approach and fixation methods of the surgeon are recommended.

• Archives of Plastic Surgery
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• 제43권1호
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• pp.88-92
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• 2016

There are two general categories of lateral osteotomy techniques-the external perforating method and the internal continuous method. Regardless of which technique is used, procedural effectiveness is hampered by limited visualization in the surgical field. Considering this point, we devised a new technique that involves using a wide subperiosteal dissection and internal perforation under direct visualization. Using an intranasal approach, whereby the visibility of the intended fracture line was maintained, enabled a greater degree of control, and in turn, results that were more precise, and thus predictable and reproducible. Traditionally, it has been taken as dogma that the periosteum must be preserved, considering the potential for dead space and bony instability; however, under sufficient visualization of the surgical field with an internal perforating method, complete osteotomy with fully preserved intranasal mucosa could be conducted exactly as intended. This intact mucosal lining compensates for the elevated periosteum. Compressive dressing and drainage through a Silastic angio-needle catheter enabled the elimination of dead space. Therefore, precise, reproducible, and predictable osteotomy minimizing the potential for associated complications such as ecchymosis, that is, bruising owing to hemorrhage, could be performed. In this article, we introduce a novel technique for lateral osteotomy with improved visualization.

• Anatomy and Cell Biology
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• 제56권1호
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• pp.39-45
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• 2023

Fixation of radial head fracture with minimally invasive posterior approach remains a significant challenge. The aim of this study was to determine the feasibility of trans-anconeus posterior elbow approach and to observe lateral ulnar collateral ligament (LUCL) in extended elbows. This cadaveric study was performed in twenty upper limbs of fresh fixed adult male cadavers. An oblique incision was made in the middle segment of anconeus until the lateral ligament complex and the joint capsule had been revealed. A deep dissection was explored to observe the anatomical relationship of the LUCL to the anconeus. Measurements of the LUCL were recorded while the elbow was fully extended. The mean distance between the edge of the radial head and the proximal insertion of the LUCL was 13.3 mm (11.5-16.2 mm); the mean distance between the edge of the radial head and the distal insertion of the LUCL was 20.9 mm (19.2-23.4 mm); the distance between the edge of the radial head and the distal edge of the annular ligament was 11.2 mm (8.22-11.7 mm). By estimate correlation of the previous measurements, the direct and accessible way to expose the posterolateral articular capsule of the elbow joint was through a window in medial 2/3 of the middle segment of anconeus muscle. These trans-anconeus approach is useful. It provides good visualization, facilitates applying the implants, and lessens the risk of radial nerve injury. Awareness of the anatomy is mandatory to avoid injury of LUCL.

• 대한관절경학회지
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• 제14권1호
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• pp.49-52
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• 2010

목적: 회전근 개 파열에서의 전외측 도달법을 이용한 소절개 봉합술을 소개하고자 한다. 수술 술기: 전신 마취하에 측와위 자세를 취한 후 후방 삽입구, 전방 삽입구를 이용하여 관절내 병변의 유무를 확인하고, 관절경을 견봉하 공간에 위치시킨 후 외측 삽입구를 이용하여 회전근 개의 파열 형태 및 크기를 파악한 후 관절경하견봉 성형술을 시행한다. 견봉의 전외측 연에서 하방으로 3~4 cm의 피부 절개를 가한 후 전방 및 중간 삼각근의 봉합선을 따라 박리하고 삼각근 견인기를 이용하여 시야를 확보한다. 파열된 건에 견인 봉합을 시행하여 해부학적 복원을 위한 위치를 확인한 후 봉합 나사를 이용하여 일열 혹은 이열 봉합술을 시행한다. 봉합술 후 견봉에서 삼각근이 견열되는 것을 방지하기 위해 1번 흡수봉합사를 이용하여 견봉과 삼각근과의 추가적인 봉합을 시행한다. 결론: 본 술기는 회전근 개의 가장 흔한 파열 부위인 극상건의 전방부에 직접 도달이 가능하고, 전방 및 중간 삼각근 사이로 접근하기 때문에 삽입구 연장 도달법에 비해 비교적 적은 견인으로도 시야를 확보할 수 있으며 전방으로는 견갑하건의 상부와 후방으로는 극하건까지 도달할 수 있는 유용한 술식으로 생각된다.

• 대한정형외과학회지
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• 제55권2호
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• pp.143-153
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• 2020

목적: 58예의 직접전방 접근법을 통한 인공 고관절 치환술의 임상결과와 학습곡선을 분석하여 학습능력이 향상되는 시점에 대하여 알아보고자 하였다. 대상 및 방법: 2016년 11월부터 2018년 11월까지 58명의 환자를 대상으로 직접전방 접근법을 사용한 인공 고관절 치환술을 시행하였다. 초기 시행한 29명과 후기 시행한 29명을 후향적으로 비교분석하였다. 수술시간과 합병증(대전자 견열 골절, 외측 대퇴피신경 손상, 이소성 골화증, 감염, 탈구 등)을 바탕으로 분석하였다. 통계적 방법은 양 군 간에 대응표본 T 검정, 카이제곱 검정과 누적합법(cumulative sum, CUSUM) 분석을 사용하였다. 결과: 수술 시간은 전치환술은 평균 132.1분, 반치환술은 평균 79.7분으로 양 군에서 유의한 차이를 보였다. 수술 기간에 따른 CUSUM 분석을 시행하였고, 전치환술에서는 16번째 증례, 반치환술에서는 14번째 증례부터 수술시간이 각각 평균 수술시간보다 감소하였다. 합병증으로 전반기에 5예, 후반기에 0예로 총 5예의 대전자 견열골절이 있었으며, 외측대퇴피하신경 손상은 전반기 8예, 후반기 2예로 총 10예, 이소성 골화증은 전반기 3예, 후반기 2예로 총 5예, 탈구와 감염은 각각 전반기 1예씩, 기타 합병증 3예가 있었다. 전반기 1년간 수술 중 발생한 대전자 견열골절은 5예(17.2%), 후반기에는 0예(0%)가 있었으며 이를 CUSUM 분석을 통해 모니터링하였으나 증례가 많지 않아 유의한 차이를 보이지는 않았다. 결론: 직접전방 접근법을 이용한 인공 고관절 치환술은 해부학적 이해가 선행되어야 하고, 수술 시야의 확보가 어렵기 때문에 습득하는 데 최소 30예 이상의 학습곡선이 필요하다.

• Anatomy and Cell Biology
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• 제57권1호
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• pp.143-146
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• 2024

The current cadaveric report describes an unusual morphology of the sartorius muscle (SM), the biceps-bicaudatus variant. The SM had two (lateral and medial) heads, with distinct tendinous origins from the anterior superior iliac spine. The lateral head was further split into a lateral and a medial bundle. The anterior cutaneous branch of the femoral nerve emerged between the origins of the lateral and medial heads. SM morphological variants are exceedingly uncommon, with only a few documented cases in the literature, and several terms used for their description. Although their rare occurrence, they may play an important role in the differential diagnosis of entrapment syndromes, in cases of neural compressions, such as meralgia paresthetica, while careful dissection during the superficial inter-nervous plane of the direct anterior hip approach is of utmost importance, to avoid adverse effects due to the altered SM morphology.

• Steel and Composite Structures
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• 제20권4호
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• pp.749-776
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• 2016

In this paper, a Performance Based Design (PBD) approach is validated for multi-storey concentrically braced frame (CBF) systems. Direct Displacement Based Design (DDBD) procedure is used and validated by designing 4- and 12-storey CBF buildings. Nonlinear time history analysis (NLTHA) is used to check the performance of the design methodology by employing different accelerograms having displacement spectra matching the design displacement spectrum. Displacements and drifts obtained from NLTHA are found to fall within the design displacement limits used in the DDBD procedure. In NLTHA, both tension and compression members are found to be resisting the base shear, $F_b$, not only the tension members as assumed in the design methodology and suggested by Eurocode 8. This is the reason that the total $F_b$ in NLTHA is found to be greater than the design shear forces. Furthermore, it is found that the average of the maximum ductility values recorded from the time history analyses for the 4-and 12-storey buildings are close to the design ductility obtained from the DDBD methodology and ductility expressions established by several researchers. Moreover, the DDBD is compared to the Forced Based Design (FBD) methodology for CBFs. The comparison is carried out by designing 4 and 12-storey CBF buildings using both DDBD and FBD methodologies. The performance for both methodologies is verified using NLTHA. It is found that the $F_b$ from FBD is larger than $F_b$ obtained from DDBD. This leads to the use of larger sections for the structure designed by FBD to resist the lateral forces.

• 한국운동역학회지
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• 제15권3호
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• pp.105-115
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• 2005

This study was investigated the kinematic factors of the last approach strides and. take off motion for the skill improving of BKH elite male athlete. 'The subjects chosen for the study were BKH and. KASZCZYK Emillian male athletes who were participated in 2003 Dae-Gu Universiad Games. Three high speed video cameras set in 60frames/s setting were used. for recording from the last approach strides to the apex position. After digitizing motion, the Direct Linear Transformation(DLT) technique was employed to obtain 3-D position coordinates, The kinematic factors of the distance, velocity and angle variable were calculated for Kwon3D 3.1. The following conclusions were drawn; 1. It showed longer stride length, as well as faster horizontal and lateral velocity than the success trial during the approach phase. For consistent of the approach rhythm, it appeared that the subject should a short length for obtain the breaking force by the lower COG during the approach phase. 2. The body lean angle showed a small angle by a high COG during the take-off phase. For obtain the vertical displacement of the COG and a enough space form the bar after take-off, it appeared that the subject should increase the body lean angle. 3. For obtain the vertical force during the takeoff phase, it appeared that the subject should keep straight as possible the knee joint. Therefor, the subject can be obtain a enough breaking force at the approach landing.

• 대한족부족관절학회지
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• 제1권1호
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• pp.15-22
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• 1997

A variety of surgical approach for ankle and tibiotalocalcaneal arthrodesis has been described. We used a transfibular approach between the sural nerve and lateral branch of the superficial peroneal nerve. This permits excellent visualization of the ankle and subtalar joint so that the fusion can readily be achieved under the direct visualization. Eight ankle fusions and four tibiotalocalcaneal fusions were carried out through a transfibular approach and reviewed. The resected fibula was utilized for bone graft. The follow up period was from 12 to 22 months. Ages of the patients ranged from 27 to 58 years. The postoperative regimen was six weeks nonweight bearing in a short leg cast, followed by weight bearing in a short leg cast until union occurred. All cases were fused except one who had preoperative pyogenic arthritis of the ankle and hindfoot. The results were as follows; 1. The chance of incisional neuroma is lessened through incision between the sural nerve and superficial peroneal nerve. 2. The possibility of a skin slough is reduced by using full thickness skin flaps. 3. Excellent visualization of the ankle and subtalar joint is easily achieved. So, we believed that the transfibular approach for ankle and tibiotalocalcaneal arthrodesis is the excellent surgical approach.