• 대한족부족관절학회지
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• 제15권2호
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• pp.102-106
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• 2011

Recently, development and improvement in joint replacement therapy, the need for arthrodesis has been decreasing. However, result of joint replacement is not always satisfactory, and most cases are rather indicative to ankle arthrodesis than ankle replacement. Often, ankle arthrodesis can be more beneficial salvage method to treat cases with failure in joint replacement therapy, talar avascular necrosis with massive bone defect, talus fracture with severe comminution and bone defect and ankle dislocation. In cases with large bone defect that need to be treated with ankle arthrodesis using internal fixation, it is difficult to fill the defect with conventional auto-iliac bone or all-bone graft. Thus, we make a report on our experience in treating 2 cases with ankle arthrodesis using auto-fibular bone graft and plate fixation.

• Archives of Reconstructive Microsurgery
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• 제22권2호
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• pp.57-62
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• 2013

Purpose: The aim of this study is to report on the results and discuss the role of free flap followed by ipsilateral vascularized fibular transposition (IVFT) for reconstruction of large bone and soft tissue defect combined with infection by open tibia fracture. Materials and Methods: During the research period, lasting from December 2002 to June 2008 (Kyung Hee University Medical Center), data were collected from three patients who underwent IVFT after free flap. We analyzed the successiveness and persistency of the infection using free flapping, bone union, and hypertrophy between transposed fibula and tibia. Results: Regarding free flap, successive results were observed in all examples. In the final follow-up results, transposed fibulas all survived, having hypertrophy similar to that of adjacent tibia. Conclusion: Reconstruction of tibia defect with free flap followed by IVTF is a useful and safe method for avoidance of the potential risk of infection for patients with a large tibial bone defect and soft tissue defect associated with infection.

• International Journal of Automotive Technology
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• 제7권6호
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• pp.741-747
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• 2006

It has been almost impossible to predict the fatigue life in the field of rubber materials by numerical methods. One of the reasons is that there are no obvious fracture criteria and excessively various ways of mixing processes. Tearing energy is considered as a fracture criterion which can be applied to rubber compounds regardless of different types of fillers, relative to other fracture factors. Fatigue life of rubber materials can be approximately predicted based on the assumption that the latent defect caused by contaminants or voids in the matrix, imperfectly dispersed compounding ingredients, mold lubricants and surface flaws always exists. Numerical expression for the prediction of fatigue life was derived from the rate of rough cut growth region and the formulated tearing energy equation. Endurance test data for dumbbell specimens were compared with the predicted fatigue life for verification. Also, fatigue life of industrial rubber components was predicted.

• 대한기계학회논문집
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• 제11권2호
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• pp.191-197
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• 1987

본 논문에서는 이상과 같이 그 중요성이 인정되는 작은 표면피로균열의 성장 특성을 조사하기 위하여 연강과 중탄소강에 두 종류의 작은 표면결함을 가공한 네가지 종류의 시험편을 제작하고, 응력비 R=-1인 소야식 회전굽힘 피로시험을 통하여 작은 표면결함이 피로강도에 미치는 영향과 그 성장특성을 조사한 후 응력확대계수 K를 사 용하는 방법과 반복전스트레인 확대계수범위 .DELTA. $K_{\epsilon}$t/를 비교 검토하여 그 유효성 을 조사하고 이를 파괴역학적 측면에서 고찰하였다.다.

• Archives of Reconstructive Microsurgery
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• 제6권1호
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• pp.63-72
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• 1997

We have evaluated the clinical results following the 46 cases of free vascularized osteocutaneous fibular flap transfer to the tibial defect combined with skin and soft tissue defect, which were performed from May 1982 to January 1997. Regarding to the operation, flap size, length of the grafted fibula, anastomosed vessels, ischemic time of the flap and total operation time were measured. After the operation, time to union of grafted fibula and the amount of hypertrophy of grafted fibula were periodically measured through the serial X-ray follow-up and also the complications and results of treatment were evaluated. In the 46 consecutive procedures of free vascularized osteocutaneous fibular flap transfer, initial bony union were obtained in the 43 grafted fibulas at average 3.75 months after the operation. There were 2 cases in delayed unions and 1 in nonunion. 44 cutaneous flaps among the 46 cases were survived but 2 cases were necrotized due to deep infection and venous insufficiency. One necrotized flap was treated with latissimus dorsi free flap transfer and the other was treated with soleus muscle rotational flap. Grafted fibulas have been hypertrophied during the follow-up periods. The fracture of grafted fibula(15 cases) was the most common complication and occurred at average 9.7 months after the operation. The fractured fibulas were treated with the cast immobilization or internal fixation with conventional cancellous bone graft. In the cases of tibia and fibula fracture at recipient site, the initial rigid fixation for the fibula fracture at recipient site could prevent the fracture of grafted fibula to the tibia.

• Archives of Plastic Surgery
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• 제34권6호
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• pp.719-723
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• 2007

Purpose: Blowout fracture can lead to functional impairments and esthetic deformities such as impairment of ocular movement, diplopia, visual loss and enophthalmos. The object of this study is to present a classification and its analysis according to the computed tomographic scan in blowout fractures. We classified blow out fractures into three types according to the anatomical location of fracture, the size of the bone defect and the degree of periosteal injury by using the computed tomography scan. Each progress and complications were analyzed more than mean 1 year. Methods: Among the 155 cases during 4 years, there were 11 cases of medial orbital wall fracture, 97 cases of inferior orbital wall fracture, 47 cases of combined type. The mean age of patients was 31.2 years, ranged from 8 to 84 years. Results: According to our classification, surgical treatments through the nasoendoscopic approach, the subciliary approach, the transconjunctival approach or their combinations were performed in 116 patients, and conservative treatments were done in 46 patients. Presurgical clinical findings of diplopia, impairment of ocular movement, enophthalmos of more than 2 mm were present in 62 patients. After surgical treatment, clinical findings were remained in 7 patients. Conclusion: We think that our classification according to computed tomographic scan is helpful for the indication and it may decrease the complications such as impairment of ocular movement, diplopia, visual loss and enophthalmos.

• Journal of Korean Neurosurgical Society
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• 제58권6호
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• pp.528-533
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• 2015

Objective : We sought to examine anatomic variations of the atlas and the clinical significance of these variations. Methods : We retrospectively reviewed 1029 cervical 3-dimensional (3D) CT images. Cervical 3D CT was performed between November 2011 and August 2014. Arcuate foramina were classified as partial or complete and left and/or right. Occipitalization of the atlas was classified in accordance with criteria specified by Mudaliar et al. Posterior arch defects of the atlas were classified in accordance with criteria specified by Currarino et al. Results : One hundred and eight vertebrae (108/1029, 10.5%) showed an arcuate foramen. Bilateral arcuate foramina were present in 41 of these vertebrae and the remaining 67 arcuate foramina were unilateral (right 31, left 36). Right-side arcuate foramina were partial on 18 sides and complete on 54 sides. Left-side arcuate foramina were partial on 24 sides and complete on 53 sides. One case of atlas assimilation was found. Twelve patients (12/1029, 1.17%) had a defect of the atlantal posterior arch. Nine of these patients (9/1029, 0.87%) had a type A posterior arch defect. We also identified one type B, one type D, and one type E defect. Conclusion : Preoperative diagnosis of occipitalization of the atlas and arcuate foramina using 3D CT is of paramount importance in avoiding neurovascular injury during surgery. It is important to be aware of posterior arch defects of the atlas because they may be misdiagnosed as a fracture.

• Journal of Korean Neurosurgical Society
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• 제42권2호
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• pp.89-91
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• 2007

Objective : Cranioplasty is necessary to repair the cranial defect, produced either by decompressive craniectomy or removal of the contaminated depressed skull fracture. Complications are relatively common after cranioplasty, being reported up to 23.6%. We examined the incidence and risk factors of infectious complications after cranioplasty during last 6 year period. Methods : From January 2000 to December 2005, 107 cranioplasties were performed in our institution. The infectious complications occurred in 17 cases that required the removal of the bone flap. We examined the age of the patients, causes of the skull defect, timing of the cranioplasty the size of the defect, and kinds of the cranioplasty material. The size of the skull defect was calculated by a formula, $3.14{\times}long\;axis\;{\times}short$ axis. The cranioplasty material was autogenous bone kept in a freezer in 74 patients, and polymethylmetacrylate in 33 patients. Statistical significance was tested using the chi-square test. Results : The infection occurred in 17 patients in 107 cranioplasties (15.9%). It occurred in 2 of 29 cases of less than $75\;cm^2$ defect (6.9%), and 6 in 54 cases of $75{\sim}125\;cm^2$ defect (11.1%). Also, it occurred in 9 of 24 cases of more than $125\;cm^2$ defect (37.5%). This difference was statistically significant (p <0.01). Conclusion : During the cranioplasty, special attention is required when the skull defect is large since the infection tends to occurr more commonly.

• 대한기계학회논문집
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• 제19권3호
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• pp.731-740
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• 1995

The objective of this paper is to develop defect assessment technology for integrity evaluation of CANDU pressure tubes. In fracture mechanics analysis, three-dimensional and two-dimensional (line-spring model) finite element analyses were performed to obtain the stress intensity factor for axial and circumferential surface cracks. In leak before break (LBB) analysis, heat transfer analyses for through-wall cracks were performed by considering the cooling effect and the LBB application time was computed. It was shown that the analytical results obtained in this study provide less-conservative but accurate solution for defect assessment of CANDU pressure tubes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권3호
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• pp.233-236
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• 2021

A mandibular continuity defect can be repaired using either a prosthetic device or autogenous bone. A titanium reconstruction plate can be used with a localized or vascularized flap over the defect of the mandible. Unfortunately, the plate may fail due to plate exposure, screw loosening, fracture, or infection, and will need to be removed. Plate exposure though the skin or mucosa is one of the main reasons for failure. In the present work, the authors introduced a lingually positioned reconstruction plate fabricated via three-dimensional printed bending support. This custom reconstruction plate can avoid plate re-exposure as well as reduce surgical errors and operation time.