• Journal of Korean Neurosurgical Society
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• 제59권2호
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• pp.91-97
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• 2016

Objective : To investigate the biomechanical effects of a newly proposed Interspinous Process Compressor (IPC) and compare with pedicle screw fixation at surgical and adjacent levels of lumbar spine. Methods : A three dimensional finite element model of intact lumbar spine was constructed and two spinal fusion models using pedicle screw fixation system and a new type of interspinous devices, IPC, were developed. The biomechanical effects such as range of motion (ROM) and facet contact force were analyzed at surgical level (L3/4) and adjacent levels (L2/3, L4/5). In addition, the stress in adjacent intervertebral discs (D2, D4) was investigated. Results : The entire results show biomechanical parameters such as ROM, facet contact force, and stress in adjacent intervertebral discs were similar between PLIF and IPC models in all motions based on the assumption that the implants were perfectly fused with the spine. Conclusion : The newly proposed fusion device, IPC, had similar fusion effect at surgical level, and biomechanical effects at adjacent levels were also similar with those of pedicle screw fixation system. However, for clinical applications, real fusion effect between spinous process and hooks, duration of fusion, and influence on spinous process need to be investigated through clinical study.

• Journal of Trauma and Injury
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• 제33권1호
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• pp.18-22
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• 2020

Purpose: Damage control laparotomy has contributed to improved survival rates for severe abdominal injuries. A large part of severe abdominal injury occurs with a concomitant pelvic bone fracture. The safety and effectiveness of internal fixation of pelvic bone fracture(s) has not been established. The aim of the present study was to evaluate infection risk in the pelvic surgical site in patients who underwent emergent abdominal surgery. Methods: This single-center retrospective observational study was based on data collected from a prospectively maintained registry between January 2015 and June 2019. Patients who underwent laparotomy and pelvic internal fixation were included. Individuals <18 and ≥80 years of age, those with no microbiological investigations, and those who underwent one-stage abdominal surgery were excluded. Comprehensive statistical comparative analysis was not performed due to the small number of enrolled patients. Results: A total of six patients met the inclusion criteria, and the most common injury mechanism was anterior-posterior compression (67%). The average duration of open abdomen was 98 hours (range, 44-98), and the time interval between abdominal closure and pelvic surgery was 98 hours. One patient (16.7%) died due to multi-organ dysfunction syndrome. Micro-organisms were identified in the abdominal surgical site in five patients (83%), with no micro-organisms in pelvic surgical sites. There was no unplanned implant removal. Conclusions: Internal fixation of pelvic bone fracture(s) could be performed in the state of open abdomen, and the advantages of early fixation may countervail the risks for cross contamination.

• 대한족부족관절학회지
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• 제14권1호
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• pp.79-83
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• 2010

Purpose: To compare the clinical and radiological results between the anterior and posterior screw fixation for the treatment of talar neck fracture. Materials and Methods: Among 30 patients who received surgical treatment for talar neck fracture from 2001 to 2008. Twenty-seven patients with a follow-up period of more than 1 year were divided into two groups. Twelve patients were treated with anterior screw fixation and 15 patients with posterior approaches. We analyzed preoperative, postoperative and follow-up radiographs. Clinical results were evaluated by Hawkins criteria. Results: The posteriorly inserted screws were placed across the more central portion of the talar neck and perpendicular to the plane of fracture (p<0.05). There were no difference in clinical results, the duration of union, and complications including avascular necrosis between two groups. However, 2 patients complained of pain around the talonavicular joint in the anterior insertion group. Conclusion: Although the clinical results were good irrespective of insertion methods, the posterior approach of screw fixation for talar neck fractures allows for a better mechanical advantage than anterioly placed screws. This may allow early motion with a reduced risk of failure of fixation or of displacement of the fracture.

• Clinics in Shoulder and Elbow
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• 제19권1호
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• pp.8-14
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• 2016

Background: The purpose of this study was to investigate the difference between two nailing approaches of intramedullary screw fixation, the retrograde nailing versus the anterograde nailing, on the radiological and clinical outcomes in patients with clavicle shaft fractures. Methods: From April 2002 to August 2014, we enrolled a total of 22 patients with clavicle shaft fractures to participate in this study. Twelve patients received retrograde intramedullary nailing and 10 received anterograde nailing. The average duration of follow-up was 12 months. In all the patients, we took follow-up radiographs of the anteroposterior and the axial views to assess the postoperative radiological outcomes. We measured the visual analogue scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score, and the range of motion (ROM). Results: Clinically, we did not find a statistically significant difference in the retrograde group and the anterograde group in terms of the duration to bone union, the VAS score the ASES score and the ROMs. Radiologically, we found that the difference in the clavicle shortening of the affected arm and the unaffected arm did not show a statistically significant difference at the immediate postoperative assessment. we found that the difference in the clavicle shortening of the affected arm between the immediate postoperative and the final follow-up value did not show a statistically significant difference. Conclusions: We found that both the retrograde nailing and the anterograde nailing gave a favorable outcome for clavicle shaft fractures. Although we saw evidence of clavicle shortening after intramedullary screw fixation, this was not a factor that influenced clinical outcome.

• 한국실내디자인학회논문집
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• 제25권1호
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• pp.73-80
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• 2016

Street is the most fundamental component of city and place to promote diverse actions of people. Pedestrians gaze at various street environments. A visual gaze means that there are interesting elements and these elements need to be preferentially improved in the street environment improvement project. Therefore, this study aims to set up the priorities of street environment components by analyzing eye movements from a pedestrian perspective. In this study, street environment components were classified into road, street facility, building(facade) and sky and as street environment images, three "Streets of Youth" situated in Gwangbok-ro, Seomyeon and Busan University of Busan were selected. The experiment targeted 30 males and females in their twenties to forties. After setting the angle of sight through a calibration test, an eye-tracking experiment regarding the three images was conducted. Lastly, the subjects were asked to fill in questionnaires. The following three conclusions were obtained from the results of the eye-tracking experiment and the survey. First, building was the top priority of street environment components and it was followed by street facility, road and sky. Second, as components to be regarded as important, fast 'Sequence', many 'Fixation Counts' and 'Visit Counts', short 'Time to First Fixation' and long 'Fixation Duration' and 'Visit Duration' were preferred. Third, after voluntary eye movements, the subjects recognized the objects with the highest gaze frequency and the lowest gaze frequency.

• 대한소아치과학회지
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• 제31권3호
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• pp.453-458
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• 2004

소아에서의 하악 골절은 성인에서보다 드물다. 그러나, 어릴수록 강직과 성장장애의 가능성이 크며 성인만큼 악간고정을 잘 견뎌내지 못한다. 반면에, 골절은 소아에 있어 더 빨리 치유되고 합병증도 적다. 소아에서 하악 골절은 종종 하악의 acrylic splint therapy 단독 또는 eyelet wire 와 악간 고정을 같이 사용하여 성공적으로 치료될 수 있다. 발생할 수 있는 심각한 합병증으로는 유착과 성장장애가 있다. 이러한 합병증의 빈도와 심각성은 좀더 짧은 기간의 악간고정과 긴밀한 술 후 관리에 의해 감소될 수 있다. 특히 소아 환자가 악간고정을 잘 견디지 못하는 경우, 악간고정의 기간이 길어지는 경우, 환자의 자발적인 운동요법이 어려운 경우 악간고정이 불필요하고 개구장애 만을 일으킨 미약한 증상의 경우에는 동기부여에 의한 물리적 하악 운동요법이 사용될 수 있다. 본 종례에서는 하악정중부의 외상으로 인하여 양측성 과두 골절이 일어난 6세 여자 환아를 대상으로 상, 하악에 elastic을 이용하여 하악의 개구, 측방, 전방운동에 대해 훈련을 가능하게 하는 Benoist씨 장치를 이용한 능동적 하악 운동 요법으로 7개월 간의 정기 검진을 통하여 하악 운동량의 증진 과두 유착의 방지, 골개조의 치료효과를 보였다.

• Journal of Microbiology
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• 제35권3호
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• pp.181-187
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• 1997

Filamentous cyanobacteria are an ecologically important group of bacteria because they are able to provide both organic carbon fixed nitrogen that can support the nutritional requirements for other microorganisms. Because of their prokaryotic nature, they can also be used as potentially powerful model systems for the analysis of oxygenic photosynthesis and nitrogen fixation. Gene transfer is an indispensable procedure for genetic analysis of filamentous cyanobacteria. Electroporation was used to introduce foreign DNA into cyanobacterial cells. In experiments designed to optimize the electroporation technique, the effects of the field strength (amplitude of pulse) and time constant (duration of pulse), DNA concentration and host restriction/modification of DNA on the efficiency of electro-transformation were investigated. The results of this research revelaed that a high voltage pulse of short duration was effective for the electro-transformation of Anabaene sp. M131. The maximal number of transformants was obtained at 6 kV/cm with a pulse duration of 5 msec. The efficiency of electro-transformation was also sensitive to concenetration of DNA; even small amounts of DNA (0.01 .mu.g/ml) were able to gie a large number of transformants (1.0 * 10$\^$3/ cfu/ml).

• Clinics in Shoulder and Elbow
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• 제1권2호
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• pp.198-204
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• 1998

Unstable fractures of the proximal humerus continue to be difficult problems for orthopaedic surgeons. The optimum treatment of these fractures has remained a matter of controversy. We analyzed the clinical results of open reduction and plate fixation underwent for patients of unstable fractures of proximal humerus after minimum 12 months follow up. The purpose of this study is to evaluate the efficacy of open reduction and rigid plate fixation. Twenty-two patients were managed with open reduction and plate fixation. Mean follow up duration was 20.6 months(range, 12 to 28 mon.). Because the age of patient as a maker of degree of osteoporosis was considered the key factor in the success of anatomic reconstruction, we divided into two groups according to age. Group A was comprised of 12 cases with younger than 50 yrs of age. Ten cases of older than 50 yrs of age were Group B. According to Neer's classification, five cases(22%) were two part fracture, 12 cases(64%) were three part fracture, and three cases(14%) were four part fracture. We used the Neer rating system for evaluating the results. In Group A, overall scores were 79.1. In Group B, overall scores were 76.8. Overall scores in two part fracture were 85, overall scores in three part fracture 78.4 and overall scores in three part fracture 68.3. We achieved excellent or good results in nine cases(75%) of Group A and seven cases(70%) of Group B. Also, we obtained excellent or good results in all cases of two part fracture, ten cases(71%) of three fracture and one case(33%) of four part fracture. The complications were three metal loosening, one avascular necrosis of humeral head, one severe stiff shoulder, one superficial wound infection and one ectopic ossification. The results were excellent or good in 16 cases(73%) out of 22 cases. In conclusion, rigid fixation and supervised early exercise would be a good option for unstable fracture of the proximal humerus.

• 대한족부족관절학회지
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• 제21권1호
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• pp.1-6
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• 2017

Purpose: The purpose of this study was to analyze the clinical results of medial horizontal suture fixation of Akin osteotomy in hallux valgus and present its advantages. Materials and Methods: This study was based on 48 cases of 35 patients with Akin osteotomy, who underwent surgery of hallux valgus between December 2014 and July 2015, and with at least 12 months of follow-up. The mean age of patients was 46.9 years (range, 16~71 years). The mean follow-up duration was 15.9 months (range, 12~18 months). Clinical evaluations included pain visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS hallux metatarsophalangeal interphalangeal scale) score, and satisfaction score. Weightbearing anteroposterior radiographs were taken to measure the distal articular set angle (DASA) of the hallux. Radiographic bone union at 6 months follow-up was regarded as a success, while a loss of reduction and nonunion was regarded as a failure. Results: The mean pre- and postoperative pain VAS scores were 4.27 and 1.67, respectively (p<0.05). The mean AOFAS score improved from 59.7 to 80.5 (p<0.05). The DASA was improved from 8.15 to -2.57 (p<0.05). There was no case of skin irritation, cortical breakage, inflammation from the knot, and infection. All patients showed union without fixation failure. Conclusion: The clinical and radiological evaluations in this study demonstrate reliable results without complication. The medial horizontal suture fixation of the Akin osteotomy was effective, and the advantage of this procedure was unnecessity of the material removal, preservation of the joint, and no skin irritation.

• Journal of Korean Neurosurgical Society
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• 제58권1호
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• pp.65-71
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• 2015

Objective : Lumbar spinal stenosis is conventionally treated with surgical decompression. However, bilateral decompression and laminectomy is more invasive and may not be necessary for lumbar stenosis patients with unilateral radiculopathy. We aimed to report the outcomes of unilateral laminectomy and bilateral pedicle screw fixation with fusion for patients with lumbar spinal stenosis and unilateral radiculopathy. Methods : Patients with lumbar spinal stenosis with unilateral lower extremity radiculopathy who received limited unilateral decompression and bilateral pedicle screw fixation were included and evaluated using visual analog scale (VAS) pain and the Oswestry Disability Index (ODI) scores preoperatively and at follow-up visits. Ligamentum flavum thickness of the involved segments was measured on axial magnetic resonance images. Results : Twenty-five patients were included. The mean preoperative VAS score was $6.6{\pm}1.6$ and $4.6{\pm}3.1$ for leg and back pain, respectively. Ligamentum flavum thickness was comparable between the symptomatic and asymptomatic side (p=0.554). The mean follow-up duration was 29.2 months. The pain in the symptomatic side lower extremity (VAS score, $1.32{\pm}1.2$) and the back (VAS score, $1.75{\pm}1.73$) significantly improved (p=0.000 vs. baseline for both). The ODI improved significantly postoperatively ($6.60{\pm}6.5$; p=0.000 vs. baseline). Significant improvement in VAS pain and ODI scores were observed in patients receiving single or multi-segment decompression fusion with fixation (p<0.01). Conclusion : Limited laminectomy and unilateral spinal decompression followed by bilateral pedicle screw fixation with fusion achieves satisfactory outcomes in patients with spinal stenosis and unilateral radiculopathy. This procedure is less damaging to structures that are important for maintaining posterior stability of the spine.