• 한국운동역학회지
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• 제29권4호
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• pp.255-261
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• 2019

Objective: The purpose of this study was to investigate differences of shock attenuation strategies between double-leg and single-leg landing on sagittal plane using statistical parametric mapping. Method: Nine healthy female professional soccer players (age: 24.0±2.5 yrs, height: 164.9±3.3 cm, weight: 55.7±6.6 kg, career: 11.2±1.4 yrs) were participated in this study. The subjects performed 10 times of double-leg and single-leg landing from the box of 30 cm height onto force plates respectively. The ground reaction force, angle, moment, angular velocity, and power of the ankle, knee, and hip joint on sagittal plane was calculated from initial contact to maximum knee flexion during landing phase. Statistical parametric mapping was used to compare the biomechanical variables of double-leg and single-leg landing of the dominant leg throughout the landing phase. Each mean difference of variables was analyzed using a paired t-test and alpha level was set to 0.05. Results: For the biomechanical variables, significantly increased vertical ground reaction force, plantarflexion moment of the ankle joint, negative ankle joint power and extension moment of the hip joint were found in single-leg landing compared to double-leg landing (p<.05). In addition, the flexion angle and angular velocity of the knee and hip joint in double-leg landing were observed significantly greater than single-leg landing, respectively (p<.05). Conclusion: These findings suggested that negative joint power and plantarflexion moment of the ankle joint can contribute to shock absorption during single-leg landing and may be the factors for preventing the musculoskeletal injuries of the lower extremity by an external force.

• 한국융합학회논문지
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• 제11권9호
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• pp.59-63
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• 2020

본 연구는 엘리트 레슬링선수들이 주로 발생하는 스포츠 손상유형을 알아보고, 그에 따른 시각적 상사 척도와 회복 기간 그리고 시각적 상사 척도와 회복 기간이 어떠한 관계가 있는지 알아보고자 하였다. 손상 유형별 발생률은 포아송 비로 계산하였으며, 손상유형에 따른 시각적 상사 척도와 회복 기간은 일원분산분석을 시행하였다. 또한, 시각적 상사 척도와 회복 기간의 관계를 알아보기 위해 단순선형 회귀분석을 시행하였으며, 모든 통계의 유의성은 α=.05로 하였다. 연구결과 인대 손상이 가장 높았으며, 그다음으로는 근육 손상, 연골 손상 그리고 힘줄 손상 순이었다. 손상유형에 따른 시각적 상사 척도는 통계적으로 유의하였으며(p=.001), 회복 기간에서도 통계적으로 유의하였다(p=.001). 또한, 시각적 상사 척도가 1씩 증가할 경우, 회복 기간은 약 1.89일씩 길어졌다(p=.001). 이러한 연구들은 선수들의 안전한 선수 생활과 스포츠 현장 복귀를 위한 유용한 이론적 배경으로 제공될 것이다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권6호
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• pp.339-346
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• 2023

Objectives: This analysis details the characteristics of dental trauma in South Korea during the coronavirus disease 2019 (COVID-19) (DC) pandemic and compares them in patients before and after COVID-19 (BC and AC, respectively). Materials and Methods: Data were collected from medical records of patients who visited Seoul National University Bundang Hospital's Emergency Dental Care Center during three 12-month periods: BC, DC, and AC (BC from March 1, 2019 to February 29, 2020; DC from March 1, 2020 to February 28, 2021; AC from March 1, 2022 to February 28, 2023). A retrospective review was conducted to investigate patient age, sex, time of visit, cause, and diagnosis. The study included 1,544 patients: 660 BC, 374 DC, and 510 AC. Results: Significant difference in age and sex was not observed among the three periods; 1-9 years of age was the largest group (38.3% in BC, 29.6% in DC, and 27.8% in AC), and the percentage of male patients was greater than of female patients (male proportion as 63.5% in BC, 67.4% in DC, and 64.9% in AC). The number of patients generally peaked at a Saturday night in spring (for BC: May, Saturday, 18:00-19:59; for DC: March, Saturday, 18:00-19:59; for AC: April as the second most (October as the most peaked), Saturday, 20:00-21:59). The primary etiology of the dental trauma was identical in the three periods: falls, followed by sports. The most frequent diagnosis was laceration, followed by tooth avulsion and jaw fracture. Conclusion: Significant differences were not found between the characteristics and patterns of dental trauma in the BC, DC, and AC periods. However, due to the pandemic and social distancing, activities decreased and associated dental trauma-related incidents declined.

• Advances in concrete construction
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• 제16권6호
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• pp.291-302
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• 2023

As the first part of the body that strikes the ground during running, sports shoes are especially important for improving performance and reducing injuries. The use of new nanotechnology materials in the shoe's sole that can affect the movement angle of the foot and the ground reaction forces during running has not been reported yet. It is important to consider the material of the sole of the shoe since it determines the long-term performance of sports shoes, including their comfort while walking, running, and jumping. Running performance can be improved by polymer foam that provides good support with low energy dissipation (low energy dissipation). Running shoes have a midsole made of ethylene propylene copolymer (EPP) foam. The mechanical properties of EPP foam are, however, low. To improve the mechanical performance of EPP, conventional mineral fillers are commonly used, but these fillers sacrifice energy return. In this study, to improve the magnificence of physical education training with nanotechnology, carbon nanotubes (CNTs) derived from recycled plastics were prepared by catalytic chemical vapor deposition and used as nucleating and reinforcing agents. As a result of the results, the physical, mechanical, and dynamic response properties of EPP foam combined with CNT and zinc oxide nanoparticles were significantly improved. When CNT was added to the nanocomposites with a weight percentage of less than 0.5 wt%, the wear resistance, physical properties, dynamic stiffness, compressive strength, and rebound properties of EPP foams were significantly improved.

• 한국운동역학회지
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• 제34권1호
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• pp.25-33
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• 2024

Objective: The purpose of this study was to compare the lower extremity muscle activity and knee joint load according to movement speed conditions during the barbell back squat. Method: Nine males with resistance training experience participated in this study. Participants performed the barbell back squat in three conditions (Standard, Fast, and Slow) differing movement speed. During the barbell back squat, muscle activity of the rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), biceps femoris long head (BFL), semitendinosus (ST), gluteus maximus (GM), gastrocnemius (GCN), and tibialis anterior (TA) was collected using an 8 channel wireless EMG system. The peak flexion angle of the lower extremity joints and the peak resultant joint force in each direction of the knee joint were calculated using eight motion capture cameras and ground reaction force plates. This study was to used the Friedman test and the Wilcoxon signed rank test, to compare lower extremity muscle activity and peak resultant joint force at knee joint according to movement speed conditions during the barbell back squat, and the statistical significance level was set at .01. Results: In the downward phase of the barbell back squat, the RF and TA showed the higher muscle activity in the fast condition, and in the upward phase, RF, VL, VM, BFL, ST, GM, and TA showed the higher muscle activity in the fast condition. As a results, analyzing of the load on the knee joint, in the downward phase, and in the upward phase, the higher peak compressive force of the knee joint was showed in the fast condition. Conclusion: The barbell back squat with fast movement speed was more effective due to increased muscle activity of lower extremity, but one must be careful of knee joint injuries because the load on the knee joint may increase during the barbell back squat with fast movement speed.

• Journal of Oral Medicine and Pain
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• 제37권4호
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• pp.251-256
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• 2012

오늘날 삶의 질에 대한 관심이 고조되면서 일반 대중에게서도 레져 및 스포츠가 활성화됨에 따라 구강악안면영역 외상의 발생빈도도 높아지고 있다. 이러한 구강악안면영역의 외상을 예방하기 위해 구강보호장치 사용의 중요성이 커지고 있으며, 그 중 가장 많이 사용되는 것이 마우스가드이다. 마우스가드는 1) 치아에 가해지는 충격을 흡수하고 변형시켜 치아의 손상을 방지; 2) 입술, 혀, 치은 등 연조직의 열상을 예방; 3) 충격의 발생 시 반대측 치아가 접촉되는 것을 예방; 4) 하악골을 안정화시켜 하악각 또는 하악과두의 파절을 유발할만한 충격을 흡수시킴; 그리고 5) 목 또는 뇌손상을 예방할 수 있다. 이렇듯 마우스가드가 구강악안면영역의 외상방지에 효과적이지만, 운동선수나 일반 대중들에게는 널리 보급되어 있지 않고 그 중요성에 대한 인식률도 저조한 실정이다. 레져나 스포츠 활동 시 나타날 수 있는 구강악안면 외상 예방에 가장 효과적인 마우스가드의 종류, 재료, 제작 시 고려할 사항 등을 알아보고, 사용실태에 대한 고찰을 통해 마우스가드의 중요성에 대한 인식과 대중화에 도움이 되고자 한다.

• Archives of Plastic Surgery
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• 제34권3호
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• pp.365-370
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• 2007

Purpose: There are many reports about facial bone fractures, but limited to retrospective data of a single hospital. Etiology and severity of the facial bone fracture have been changed and treatment method and materials have been advanced. In order to reflect those changes and provide up-to-date data of the facial bone fractures in Daegu, we gathered the data and analyzed the epidemiologic study. Methods: The medical records of 1058 fractures in 895 patients were gathered from 5 general hospitals in Daegu during last year and these data were analyzed by following parameters: age, sex, place of residence, occupation, cause of injury, time of injury, location of fracture, length of in-hospital stay, time of operation, treatment method, associated injury, complication. Statistical analysis was performed using the Chi-square test. Results: Most commonly involved age group was 20s(26%) and the sex ratio was 3.4:1(male predominance). Fractures were occurred more in unban and white-color workers. Among variable etiology of injury, traffic accident was the most common cause. Time of injury was heighest at 6 to 7 P.M., on Sunday, in July. Locations of fractures were following sequence: nasal, zygoma, mandible, orbit, maxilla. Mean length of in-hospital stay and time of operation after injury were 6.3 and 3.2 days, respectively. In treatment methods, operative methods were dominant than conservative management and general anesthesia were favored than local anesthesia. Associated injuries were noticed in 188 cases(21.2%) and complications were in 94 cases(8.9%) and among them, ocular problem were common. Conclusion: Compared to previous studies, mean age of occurrence was lowered and the etiologies showed age-specific pattern and reflected the change of lifestyle. In young age groups, sports injury, violence were more dominant and the other hand, traffic accident and fall were dominant in older groups.

• 대한정형외과스포츠의학회지
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• 제5권2호
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• pp.141-146
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• 2006

목적: 축구 경기 시의 무릎 손상의 형태와 기전을 분석하고 치료 후 기능 회복 정도를 평가하고자 하였다. 대상 및 방법: 2002년 10월부터 2005년 1월까지 축구로 인해 무릎 손상을 받은 49명의 환자를 대상으로 하였으며, 환자의 평균 연령은 28.8$(14\sim45)$세였고, 평균 추시 기간은 14.9$(8\sim36)$개월이었으며, 손상 평가는 이학적 소견, 방사선적 검사, 진단적 관절경술을 통해서 이루어졌으며, 술 후 기능 평가는 기능도와 활동도를 이용하였다. 결과: 인대손상에 따른 분류는 전방 십자인대 단독 손상 27례로 가장 많았고 손상에 영향을 미치는 인자는 경기 중 후반부 계절 중 겨울, 경기 빈도가 1달에 5례 이하인 경우 등이었다. 손상의 기전은 turn & twisting이 20례로 가장 많았고, being tackle 순 이었다. 손상시 기능도와 활동도는 각각 45, 2이었으며, 최종 추시 시 86.7, 6이었으며, 다발성 인대 손상 군에서 가장 나쁜 결과를 보였다. 결론: 치료 후 기능도와 활동도의 회복은 양호했지만 스포츠 활동도에서 수상전과 뚜렷한 차이를 보여 적절한 정신적, 육체적 재활과 스포츠 복귀 프로그램이 필요할 것으로 사료된다.

• 대한물리치료과학회지
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• 제3권2호
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• pp.943-950
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• 1996

Taping is used to restrict undesired, potentially harmful motion and allow desired motion. Taping refers to the application of some type of adhesive backed tape, that adheres to the skin of a particular joint or to a limb. Prevention and rehabilitation is two main indications for the use of taping techniques. The purpose of this study was to compare a tennis injury between taping and non-taping group. The objects of this study were 64 tennis club members-38 non-taping group, 26 taping group. The analysis methods were both frequency and paired T-test. The results are followings: 1. There was effective increase of taping group-elbow, wrist, knee, ankle-that showed significant increase on statistical analysis. (P<.05). 2. There was effective a relation of seasons and injured in taping group-elbow, wrist, ankle-(P<.05) 3. But non-significant statistically about injured seasons. Prophylactic taping has become one of the most common methods employed to prevent sports injuries, despite questions regarding its efficacy. The success of taping does not only depend upon the materials or methods used, but also upon the phychologic sedative effect of the athlete to be taped.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권3호
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• pp.201-206
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• 1998

We reviewed 240 patients with facial bone fractures treated at the department of oral and maxillofacial surgery between Jan. 1. 1997 to Dec. 31. 1997. These results were obtained as follows : 1. The ratio of men to women was 3.5 : 1 2. The age frequency was highest for people in their 20's 34.2%, in their 10's 21.63%, and in their 30's 20.41%. 3. The fractures were at the highest incidence in September at 13.3%, followed by in May at 11.25%. 4. The frequent causes were traffic accidents 47.9%, fisticuffs 20%, accidents caused by falling or slipping 16.25%, working traumas 8.75%, and sports 7.1%. 5. The most common location of facial bone fractures was the mandible 67.2%. The frequent fracture sites of the mandible were symphysis, angle, condyle, and body in the order. 6. The associated injuries of facial bone fractures were neurosurgry, orthopedic surgery, cardiothoracic surgery, ophthalmic surgery and general surgery. 7. In respect of treatment, open reduction used 84.3% of the time. 8. Post operation complicatins were as follows : neurological problem 2.08%, malunion 1.67%, facial asymetry 0.83%, malocclusion 0.83%, and infection 0.41%.