Does the Surgical Approach Matter in Treating Odontoid Fractures? A Comparison of Mechanical Complication Rates Between Anterior Versus Posterior Surgical Approaches: A Meta-Analysis and Systematic Review

Woong Rae Jo,Chang Young Lee,Sae Min Kwon,Chang Hyun Kim,Min Yong Kwon,Jae Hyun Kim,Young San Ko 대한신경손상학회 2023 Korean Journal of Neurotrauma Vol.19 No.4

Objective: Odontoid fractures are treated surgically through the anterior or posterior approach. Each surgical approach has its advantages and disadvantages, so the preferred approach remains debatable. There are few meta-analyses or systemic reviews on the mechanical complications of surgical treatment for odontoid fractures. This meta-analysis aimed to compare the operation-related morbidity, including mechanical complications, and mortality of patients with odontoid fractures, treated via the anterior or posterior approach. Methods: A systematic search was performed on PubMed/Medline, Embase, and the Cochrane Library for the studies up to October 2023 on the complication rate of the surgical treatment of odontoid fractures, related to the surgical approach. The risk ratios (RR) with the 95% confidence intervals (CIs) were pooled to assess the mechanical complication rates, other complications, revision surgery, and mortality, depending on the surgical approach. Results: A total of 1,519 studies were retrieved using the search strategy, and 782 patients from 15 articles were included in this meta-analysis. Mechanical complications were significantly more frequent in the anterior surgical group with low heterogeneity. The incidences of fracture nonunion and revision surgery were also higher in the anterior surgery group. However, there was no significant difference in systemic complications and mortality rates between the two groups. Conclusion: The posterior approach was more advantageous than the anterior approach in terms of mechanical complications, fusion rates, and incidence of revision surgery. However, further studies, should be performed to strengthen these results.

A 3D-Printed Model for High Sacrectomy of a Marjolin’s Ulcer–Associated Sacral Tumor: A Case Report and Literature Review

Jo Woong Rae,Kwon Sae Min,Lee Chang-Young,Kim Chang-Hyun,Kim In Soo,Choi Jaehoon,정혜라,Ko Young San 대한말초신경학회 2024 The Nerve Vol.10 No.1

Marjolin’s ulcer is a rare but aggressive form of skin cancer that often presents significant surgical challenges due to the complex anatomy of the pelvis and the necessity for wide excision to avoid recurrence. This case report highlights the innovative use of a 3-dimensional (3D)–printed model for the precise planning and successful execution of a high partial sacrectomy in a 48-year-old male patient with quadriplegia. This patient, who had sustained a cervical spine injury in 1996, developed a sacral pressure sore that progressed into a Marjolin's ulcer. Utilizing high-resolution 3D computed tomography scans, we created a detailed 3D-printed model of the patient's sacrum, which facilitated a thorough understanding of the tumor's anatomy and its spatial relationships with critical structures. This approach significantly aided the surgical team in executing a challenging excision while minimizing risk to the adjacent organs. This case underscores the potential of 3D printing technology to enhance surgical planning and outcomes in complex oncological resections, particularly in anatomically challenging regions.

Overwintering, Damage and Seasonal Fluctuation of Two Sesiid Moths, Nokona regalis and Toleria romanovi in Vineyards

Chang Yeol Yang,Myoung Rae Cho,Sung Jong Kim,Se Woong An,Kyung Ho Cho 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.10

Nokona regalis (Butler) and Toleria romanovi (Leech) (Lepidoptera: Sesiidae) are economically important pests of grape in northeast Asia. We compared the overwintering, damage and seasonal flight activities of these two species in Korean vineyards. Mature larvae of N. regalis overwintered in the infested shoots of grape, while T. romanovi overwintered as mature larvae enclosed within a cocoon in the soil. Larvae of the former species fed primarily in grape shoots (97.2%), whereas larvae of the latter species burrowed into main trunks (57.4%) and branches (40.4%), causing significant damage and frequent mortality. The seasonal fluctuation of male catches was monitored with pheromone traps in 2010. Male moths of N. regalis were present from late May until middle June, and peak abundance occurred in early June. T. romanovi males were trapped from early June to early August with peak catch in middle July in Suwon.

Early and Two-year Outcomes after Sutureless and Conventional Aortic Valve Replacement: a Nationwide Population-based Study

Jae Woong Choi,Ho Jin Kim,Joon Bum Kim,Sak Lee,Cheong Lim,Byung Chul Chang,Youshin Suh,Na Rae Lee,Ho Young Hwang 대한의학회 2021 Journal of Korean medical science Vol.36 No.9

Background: We compared early and 2-year clinical outcomes of sutureless aortic valve replacement (SAVR) with conventional aortic valve replacement (CAVR) in a nationwide study based on claims data. Methods: From December 2016 to November 2018, 3,173 patients underwent bioprosthetic aortic valve replacements. SAVR and CAVR were performed in 641 and 2,532 patients, respectively. Propensity score-matched analysis was performed in 640 patient pairs. Results: Operative mortality rate was 2.8% without significant differences between the SAVR (3.4%) and CAVR (2.3%) groups (P = 0.324). There were no significant differences in postoperative morbidities between the groups except for permanent pacemaker (PPM) implantation. PPM implantation rate was significantly higher in the SAVR (3.8%) than in the CAVR group (0.9%) (P < 0.001). One- and two-year overall survival was 89.1% and 87.5%, respectively, without significant differences between the groups (SAVR group vs. CAVR group = 89.9% and 90.5% vs. 87.2% and 88.7%, respectively; P = 0.475). There were no significant differences in the cumulative incidence of cardiac death, stroke, aortic valve reoperation and infective endocarditis between the groups. Cumulative PPM implantation incidence at 6 months in the CAVR was 1.1%, and no patient required PPM implantation after 6 months. In the SAVR, the cumulative PPM implantation incidence at 0.5, one, and two years was 3.9%, 5.0% and 5.6%, respectively. The cumulative PPM implantation rate was higher in the SAVR group than in the CAVR group (P < 0.001). Conclusion: Early and 2-year clinical outcomes between SAVR and CAVR were not different except for a high rate of permanent pacemaker implantation in the SAVR group.

해외 발사체 상단의 충돌 및 오염 회피 기동 분석

박창수(Chang-Su Park),조상범(Sangbum Cho),송은정(Eun-Jung Song),노웅래(Woong-Rae Roh) 한국항공우주연구원 2008 항공우주기술 Vol.7 No.1

발사체 상단은 위성과 분리된 이후 대부분 충돌 및 오염 회피 기동을 수행한다. 이러한 기동을 통하여 위성은 안전하게 궤도에 안착되고 발사체는 위성으로부터 오염을 최소화하며 멀어지게 된다. 본 논문에서는 해외 여러 발사체들의 위성 분리와 충돌 및 오염 회피 기동을 분석하였고 이를 토대로 KSLV-Ⅰ 상단에 회피 기동에 의한 위성의 오염도 허용 기준을 제시하였다. The launch vehicle upper stage generally executes collision and contamination avoidance maneuver after the satellite separation. Through this maneuver the satellite safely settles in its orbit and the launch vehicle moves away from the satellite with minimum contamination. In this paper collision and contamination avoidance maneuvers by foreign launch vehicles are analyzed. Criteria for satellite contamination during the avoidance maneuver is given for KSLV-Ⅰ upperstage.

항력에 의한 속도 손실 및 궤도 수명 예측

박창수(Chang-Su Park),조상범(Sangbum Cho),노응래(Woong-Rae Roh) 한국항공우주연구원 2006 항공우주기술 Vol.5 No.2

고도 800㎞ 이내의 저궤도 위성에 가장 큰 영향을 주는 요소는 지구 대기 항력이다. 지구 저궤도의 대기 밀도는 해수면의 대기 밀도에 비하여 매우 낮지만 항력에 의한 영향이 매 주기 마다 누적되면서 근지점에서 속도가 점진적으로 줄어든다. 근지점에서의 속도 감소는 곧바로 원지점의 고도 감소를 가져오게 되고 이심률이 작아지면서 최종적으로 원궤도로 바뀌게 된다. 본 논문에서는 이러한 대기 항력 및 수명 계산 방법에 대하여 기술하였다. 또한 항력의 크기를 결정하는 대기 밀도에 관해서 알아보고 KSLV-I에 사용될 킥모터와 위성의 수명을 Satellite Tool Kit 프로그램으로 계산하였다. Atmospheric drag is the most significant factor effecting the low Earth satellites under the altitude of 800㎞, Although the atmospheric density of the low Earth orbit is very low compared to that of the sea level, the accumulated effect of the atmospheric drag slowly lowers the satellite velocity at the perigee. Decrease in velocity at perigee directly causes decrease in altitude at apogee which changes the eccentricity of the orbit. The orbit finally reaches a circular orbit before reentering the Earth. This paper states the methods of calculating the atmospheric drag and the lifetime of the satellite. The lifetime of the kick motor and the satellites which will be used on KSLV-I are calculated by Satellite Tool Kit.

스테인리스강의 LASER 탈예민화

이창희,김기철,장래웅 대한금속재료학회(대한금속학회) 1992 대한금속·재료학회지 Vol.30 No.1

This paper addresses the fundamental understanding of sensitization phenomenon in stainless steel and a method of desensitization utilizing a high energy density beam of LASER. Degree of sensitization was evaluated with the state of the art technique of EPR and was correlated with microstructural changes characterized by TEM(STEM), SAD and SEM. Laser desensitization could be obtained with a proper choice of beam power and scanning rate under a constant beam size. As long as the scan rate was lower than a critical rate under a constant beam power, carbides and Cr depleted zone were completely disappeared. Further, as a cooling rate after laser treatment was significantly greater than a critical cooling rate for reprecipitation of carbides, re-sensitization would not be occurred during cooling. The critical scan rate increased with an increase in a beam power, but was constant regardless of the original degree of sensitization.

스테인리스강 Laser 용접부의 균열 특성

이창희,장래웅 대한금속재료학회(대한금속학회) 1993 대한금속·재료학회지 Vol.31 No.6

The LASER weldability response (solidification cracking and cold cracking susceptibility) of austenitic, ferritic and martensitic grades revealed a significant alloy to alloy and heat to heat variation. the ferritic and martensitic alloys appeared to be less sensitive to solidification cracking but sensitive to cold cracking such that when the hydrogen content in shielding gas increased the fracture strength and time decreased, indicating that LASER welding of these grades should be kept from absorption of hydrogen. On the other hand, austenitic alloys showed a high propensity to solidification (hot) cracking in stead of cold cracking. Sensitivity was predominantly dependent upon the primary solidification mode (Cr_(eq)/Ni_(eq)) and impurity (S, P, Si) contents.

Baseline Clinical and Biomarker Characteristics of Biobank Innovations for Chronic Cerebrovascular Disease With Alzheimer’s Disease Study: BICWALZS

Roh Hyun Woong,Kim Na-Rae,이동기,Cheong Jae-Youn,Seo Sang Won,Choi Seong Hye,Kim Eun-Joo,Cho Soo Hyun,Kim Byeong C.,Kim Seong Yoon,Kim Eun Young,Chang Jaerak,Lee Sang Yoon,Yoon Dukyong,Choi Jin Wook,An Y 대한신경정신의학회 2022 PSYCHIATRY INVESTIGATION Vol.19 No.2

Objective We aimed to present the study design and baseline cross-sectional participant characteristics of biobank innovations for chronic cerebrovascular disease with Alzheimer’s disease study (BICWALZS) participants.Methods A total of 1,013 participants were enrolled in BICWALZS from October 2016 to December 2020. All participants underwent clinical assessments, basic blood tests, and standardized neuropsychological tests (n=1,013). We performed brain magnetic resonance imaging (MRI, n=817), brain amyloid positron emission tomography (PET, n=713), single nucleotide polymorphism microarray chip (K-Chip, n=949), locomotor activity assessment (actigraphy, n=200), and patient-derived dermal fibroblast sampling (n=175) on a subset of participants.Results The mean age was 72.8 years, and 658 (65.0%) were females. Based on clinical assessments, total of 168, 534, 211, 80, and 20 had subjective cognitive decline, mild cognitive impairment (MCI), Alzheimer’s dementia, vascular dementia, and other types of dementia or not otherwise specified, respectively. Based on neuroimaging biomarkers and cognition, 199, 159, 78, and 204 were cognitively normal (CN), Alzheimer’s disease (AD)-related cognitive impairment, vascular cognitive impairment, and not otherwise specified due to mixed pathology (NOS). Each group exhibited many differences in various clinical, neuropsychological, and neuroimaging results at baseline. Baseline characteristics of BICWALZS participants in the MCI, AD, and vascular dementia groups were generally acceptable and consistent with 26 worldwide dementia cohorts and another independent AD cohort in Korea.Conclusion The BICWALZS is a prospective and longitudinal study assessing various clinical and biomarker characteristics in older adults with cognitive complaints. Details of the recruitment process, methodology, and baseline assessment results are described in this paper.

대퇴 전자간 골절에서 금속정 고정술 시행결과 : 감미정과 근위 대퇴정의 비교 Comparision Gamma Nail and proximal Femoral Nail

고상봉,조명래,김태훈,장일웅 대한골절학회 2004 대한골절학회지 Vol.17 No.4

목적: 대퇴 전자간 골절 환자에서 감마정과 근위 대퇴정으로 내고정을 시행하고 방사선학적, 임상적 결과 및 합병증을 비교하여 각각의 장단점을 분석하고자 하였다. 대상 및 방법: 1999년 1월부터 2002년 2월까지 대퇴 전자간 골절로 감마정과 근위 대퇴정을 이용하여 고정한 환자 중 방사선학적 및 임상적으로 6개월 이상 추시가 가능하였던 63예를 대상으로 하였으며 감마정군이 31예, 근위 대퇴정군이 32예이었다. 연령, 골절의 형태와 안정성에 따른 분류, 동반 질환, 골다공증의 정도, 환자의 활동 능력 등이 양 군에서 차이가 없었다. 평가방법으로는 두 군 사이의 수술시간, 출혈량, 안정정복 획득의 감입 정도 등을 비교하였다. 결과: 수술시간은 감마정군은 평균 103±40분, 근위 대퇴정군에서 101±28분으로 통계적인의미는 없었으며 (p=0.801), 수술 중 출혈량은 근위 대퇴정군에서 적은 경향을 보였으나 통계적인 의미는 없었다(p=0.601). 술 후 골절의 안정성 획득 여부는 감마정군 30%, 근위 대퇴정군 31%에서 안정 정복을 얻어 사용기구에 따른 고정의 안정성 획득에는 유의한 차이가 없었으며(p=0.934), 술 후 내반 고정의 빈도와 골절부위의 1.28단계의 보행능력 감소를, 근위 대퇴정군에서 평균 0.86단계의 보행능력 감소를 보여 역시 통계적으로 의미있는 차이는 없었다(p=0.383). 결론: 대퇴 전자간 골절치료에 있어서 임상적 및 방사선학적인 결과에서는 의미있는 차이는 없었으나, 근위 대퇴 골수정이 수술시간, 출혈량 등의 수술 수기의 측면에서 조금 더 우수한 경향을 보였다. Purpose: To evaluate the clinical and radiologic results of the fracture using the Proximal Femoral Nail(PFN) or Gamma nail in patient with the intertrochanteric fracture. Materials and Methods: From January 1999 to February 2002, we reviewed 63 patients of intertrochanteric fractures including 31 patients managed with Gamma nail and 32 patients with PFN. In variate analysis of age, the pattern and stability of fracture, bone density(Singh index), preoperative patient activity, there was no difference between two groups. We evaluated the operation time, blood loss, stable reduction rate and varus reduction rate as operation-related factors, and radiologically investigated union, time, the frequency of delayed union and nonunion, failure of fixation, status of the fracture line and complications. Functional results were evaluated by the possibility of early ambulation, ambulation ability at last follow up, and the pre and postoperative difference of ambulatory ability. Results: Mean operation time was 103±40 minutes in Gamma nail group 101±28 minutes in PFN group. It was not statistically significant(p=0.801). Even though intraoperative blood loss was less in PFN group, it was significant(p=0.601). Postoperative stable reduction rate was 31% in Gamma nail group and 30% in PFN group(p=0.934), suggesting not significant. Postoperative varus reduction and impacted amount of the fracture ling was not significant. Delayed union developed in one case of Gamma nail group and 2 cases of PFN group. Mean loss of ambulation ability was 1.28 grade in Gamma nail group and 0.86 grade in PFN(p=0.383). Statistical analysis was performed with the use of Student T test and Chi-square test. Analyses resulting in a p value of <0.05 were considered to show significance. Conclusion: Generally, the radiologic and clinical results of intertrochanteric fractures were comparable for the PFN group and Gamma nail group. Even though it was not statistically significant, PFN group had superior results in operation time blood than Gamma nail group for the fixation of the patients with interchanteric fracture.