• 한국운동역학회지
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• 제13권2호
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• pp.49-63
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• 2003

For this study, four male university Taekwondo players were randomly chosen, between the weight categories of 60Kg and 80Kg. Their side kicks (yeop chagi), which are part of foot techniques, were kinematically analyzed in terms of the time, angle, and angular velocity factors involved with the kicks through the three-dimensional imaging. The results of the analysis are as fellows. 1. Time factor The first phase(preparation) was 0.48sec on average, accounting for 60% of the entire time spent; the second phase(the minimum angle of the knee joint) was 0.21sec on average, taking up 26% of the whole time spent; and the third phase(hitting) was 0.11sec on average, representing 14% of the entire time spent. 2. Angle factor In the first phase(preparation), rotating their bodies along the long axis, the players bended their hip and knee joints a lot, by moving fast in the vertical and horizontal directions, in the second phase(the minimum angle of the knee joint), the players continued to extend their bodies along the vertical axis, while pronating their lower legs and bending their hip and knee joints a lot to reduce the radius of gyration, and in the third phase(hitting), they extended their knee joints greatly so that the angle movements of their lower bodies shifted to circle movements. 3. Angular velocity factor In the first phase(preparation), the angular velocity of the hip and knee joints increased. while moving horizontally and rotating the body along the long axis; in the second phase(the minimum angle of the knee joint), the angular velocity increased by bending the hip and knee joints fast to reduce the rotation radios; and in the third phase(hitting), the angular velocity was found to have increased, by rotating the body along the long axis to increase the angular velocity and shifting the angular momentum of the pronated knee joint to the circular momentum.

• 한국운동역학회지
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• 제18권1호
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• pp.1-10
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• 2008

본 연구는 축구 인스텝 킥에서 지지 다리의 후족각과 차는 다리의 해부학적 회전 운동의 자료들을 분석해서 다음과 같은 결론을 얻었다. 발목 관절에서의 외반각은 지지발의 접지 이전에 최대 피크에 도달했으며, 저측 굴곡은 그룹 간 최대 피크의 타이밍에서 약간의 차이가 나타났다. 지지발의 접지 시 후족의 굴곡각은 그룹 간 통계적으로 유의한 차이가 났으며, 지지발의 접지 시 하퇴의 운동은 그룹 간 유의한 차이가 없었다. 접지 이전에 이미 하퇴를 후방으로 많이 기울였으며, 임팩트 순간 하퇴의 좌우 기울기는 22도였다. 차는 다리 고관절의 굴곡/신전은 지지발의 접지 시 최대 피크에 이르렀으며, 이 순간 고관절의 최대 신전각은 30도 이상으로 나타났다. 차는 다리 무릎 관절의 굴곡각은 접지와 임팩트의 사이에 최대로 굽혔으며, 족관절의 최대 저측 굴곡각과 최대 외번각은 그룹 간 유의한 차이는 나지 않은 반면, 최대 외측 회전각은 유의한 차이가 났다.

• 구강회복응용과학지
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• 제17권4호
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• pp.231-244
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• 2001

This study was conducted to observe the effect on appendage muscle strength according to increase in occlusal vertical dimension. For this study, ten males with a mean age of 21 were selected. The subjects had a complete or almost complete set of natural teeth and reported no subjected symptoms of pain or dysfunction in the masticatory system. The tested occlusal splints were made at the position of increased occlusal vertical dimension of 2mm, 3.5mm, and 5mm from the ICP. Before and after wearing occlusal splints, the appendage muscle strength were tested by CybexII Dynamometer in each subject. The results were as follows : 1. When occlusal vertical dimension was increased, most of mean muscular strength values were increased except for those of supination and pronation of forearm at the position of 5mm increased occlusal vertical dimension. 2. The statistical analyses demonstrated that the increased occlusal vertical dimension position to be significantly stronger than intercuspal position for the muscle strength of the flexion and extension of hip, supination of forearm, external and internal rotation of knee, dorsiflexion and plantarflexion of ankle (p<0.05). 3. At the position of 3.5mm increased vertical dimension displayed the highest mean muscluar strength value than other positions. 4. Statistically demonstrated values, except for supination of forearm, internal rotation of shoulder, were related to lower appendage. Therefore splint was more effective on lower appendage than upper appendage to make muscle strength increased. 5. The mean increased rate of muscular strength tested on knee(57%), ankle(42%), and wrist(20%) were higher than hip(31%), elbow(14%), and shoulder(17%).

• 한국운동역학회지
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• 제20권1호
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• pp.33-39
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• 2010

The purpose of this study was to investigate the changes in walking pattern of the elderly during inclined walkway with uneven surfaces and level walking. 10 young($26.3{\pm}1.3$ years, $174.3{\pm}5.3\;cm$, $69.5{\pm}9.5\;kg$) and 13 elderly($72.4{\pm}5.2$ years, $164.5{\pm}5.4\;cm$, $66.1{\pm}9.6\;kg$) male subjects were participated in the experiment. Experiment consisted of 2 walking conditions: horizontal and inclined walkway with uneven surfaces. 3D motion capturing system were used to acquire and analyze walking motion data with sampling frequency of 120 Hz. To compare differences between conditions, kinematic variables(walking speed, stance-swing ratio, hip joint angle, knee joint angle, ankle joint angle, pelvic rotation angle) were used. Results showed that there were some changes of elderly walking pattern in inclined walkway with uneven surfaces: hip joint(adduction and rotation) and pelvic movement pattern. These changes by inclination and surface may affect gait pattern of young subjects as well as elderly subjects. However, in case of elderly it revealed more unstable gait than the young. Further study is necessary to clarify changes in walking pattern for elderly by considering various gait variables including head movement and various walkway conditions.

• 한국운동역학회지
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• 제23권2호
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• pp.109-116
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• 2013

The purpose of this study was to provide fundamental information for the enhancement of performance through kinematic analysis of cornering according to the radius of curve course in short track speed skating. To perform this study, six skaters: three narrow radius players(N, body mass: $56.0{\pm}7.2$ kg, height: $163.7{\pm}5.1$ cm, age: $21.3{\pm}1.5$ yrs) and three wide radius players(W, body mass: $61.0{\pm}9.5$ kg, height: $169.0{\pm}4.4$ cm, age: $20.0{\pm}1.7$ yrs). Three-dimensional motion analysis was performed on the section from the forth block starting to show the change of radius to the sixth block using eight infrared cameras(sampling frequency of 100 Hz for N and W players). The time of push-off was greater for N than for W(p<.05) while the radius of center of mass was greater for W than for N(p<.05). The flexion and extension of knee and hip joint were greater for N than for W(p<.05). The external rotation of left knee joint was greater for N than for W(p<.05). Based on the findings, a small radius by increasing the range of the flexion and extension of knee and hip joint with greater external rotation of left knee joint would be related to more efficient run at curve. It is expected that these results will be useful in developing a training program for enhancing performance of short track speed skating athletes.

• 한국운동역학회지
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• 제19권2호
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• pp.265-272
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• 2009

발목 테이핑은 상해 예방을 위해 임상적으로 이용되어 질 수 있는 보조적 수단으로 여겨지고 있다. 그러나 그동안의 연구들을 살펴보면 발목 자체에 대한 부분만을 언급하였다. 본 연구의 목적은 발목 테이핑의 적용이 기능적 발목 불안정성을 가진 선수들에게서 점프 후 착지 시에 하지 관절에 미치는 영향을 알아보는데 있다. 점프의 거리는 각 대상자 키의 50%로 결정하였으며 높이는 각 대상자 키의 20%로 결정하였다. VICON을 이용하여 하지관절의 데이터를 수집하였고, 점프 착지 동안 시상면, 관상면, 수평면의 관절 움직임의 변화를 측정하였다. 테이핑은 통계적으로 시상면에서 착지순간 저측 굴곡과 최대 저측 굴곡을 제한하는 효과가 있었으며, 반면에 착지순간 무릎 굴곡과 최대 무릎 굴곡, 착지순간 엉덩 굴곡과 최대 엉덩 굴곡을 통계적으로 유의하게 증가시키는 효과가 있었으며, 관상면에서는 최대 발목 내번, 착지순간 무릎 외반과 최대 무릎 외반, 최대 엉덩 외전을 감소시키는 효과가 있었고, 수평면에서는 최대 발목 외전, 최대 엉덩 내회전의 감소를 보였다. 발목 테이핑은 발목 관절 운동범위의 제한과 함께 무릎 관절이나 엉덩 관절에 영향을 미치는 것으로 나타났다.

• 한국전문물리치료학회지
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• 제19권3호
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• pp.81-90
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• 2012

The aim of the current study was to assess the effectiveness of backward gait training on the treadmill in patients with spastic diplegic cerebral palsy (CP). Twelve patients with spastic diplegic CP participated in the study. An 8-week course of backward gait training was administered to the subjects for 3 days per week. Pre-intervention and post-intervention assessments of temporal-spatial gait parameters, the symmetry of the bilateral lower extremity weight bearing, and gross motor function were analyzed using motion analysis system, force plate, and Gross Motor Function Measurement (GMFM). There were significant improvements (p<.05) in the measures of both step length and right stance phase time. Joint kinematics showed increase in right hip abduction in initial contact and terminal swing, right hip external rotation and knee flexion in mid-swing, left ankle dorsiflexion in initial contact and terminal swing (p<.05). The symmetry of the bilateral lower extremity weight bearing and GMFM also significantly increased (p<.05). These findings indicate that backward gait training using a treadmill is beneficial for patients with spastic diplegic CP.

• 한국운동역학회지
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• 제29권4호
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• pp.219-226
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• 2019

Objective: The purpose of this study is to provide a better understanding of short turn mechanism by describing short turns after kinematic analysis and provide skiers and winter sports instructors with data through which they are able to analyze right postures for turns in skiing in a systematic, rational and scientific manner. Method: For this, a mean difference of kinematic variables (ski-hip angle, ski-shoulder twist angle, pole checking angle, the center of gravity (CG) displacement, trunk forward lean angle) was verified against a total of 12 skiers (skilled and unskilled, 6 persons each), regarding motions from the up-start to down-end points for short turns. Results: There was no difference in a ski-hip twist angle. The ski-shoulder twist angle was large at the up-start point while a pole-checking angle was high at the down-end point in skilled skiers. Concerning the horizontal displacement of CG, skilled skiers were positioned on the right side at the upstart point. No significant difference was observed in the trunk forward lean angle. Conclusion: According to the ski-shoulder twist angle and CG horizontal displacement results, the upper body should be kept leant toward the pole. In addition, big turns should be made via edging and angulation. During pole checking, the hand holding the pole should be thrown and released toward a vector direction of the forearm.

• The Korean Journal of Pain
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• 제8권2호
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• pp.341-346
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• 1995

Piriformis Syndrome is characterized by pain of the low back, groin, perineum, buttock, hip, posterior thigh, leg and foot. Symptoms are aggravated by sitting, prolonged combination of hip flexion, adduction, the medial rotation, or by activity. In addition, patient may complain of painful swelling of the limb and sexual dysfunction-dyspareunia in female, and impotence in male. It currently appears that three specific conditions may contribute to the piriformis syndrome: (a) myofascial pain; (b) nerve and vascular entrapment; (c) dysfunction of the sacroiliac joint. The important keys of diagnosis are history and physical examination. There is no known objective diagnostic method. We described the clinical features of four cases of piriformis syndrome and reviewed foreign literature.

• 대한골관절종양학회지
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• 제3권1호
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• pp.18-25
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• 1997

Prosthetic replacement is one of the most common methods of reconstruction after resection of malignant tumor around the knee. Gait analysis provides a relative objective data about the gait function of patients with prosthesis. The purpose of this study was to compare the gait pattern of the patients who underwent limb salvage surgery with prosthesis for distal femur and that of patients with prosthesis for proximal tibia. This study included ten patients (4 males, 6 females, mean age 22.7 years, range 14-36) who underwent a wide resection and Kotz hinged modular reconstruction prosthesis replacement and six normal adult(Control). The site of bone tumor was the distal femur (Group 1) in six patients and proximal tibia (Group 2) in 4 patients. The follow-up period ranged from 15 to 82 months (mean : 33 months). The evaluation consisted of clinical assessment, radiographic assessment, gait analysis using VICON 370 Motion Analysis System. The gait analysis included the linear parameters such as, walking velocity, cadence, step length, stride length, stance time, swing time, single support and double support time and the three-dimensional kinematics (joint rotation angle, velocity of joint rotation) of ankle, knee, hip and pelvis in sagittal, coronal and transverse plane. For the kinetic evaluation, the moment of force (unit: Nm/kg) and power (unit: Watt/kg) of ankle, knee and hip joint in sagittal, coronal and transverse plane. In the linear parameters, cadence, velocity, step time and single support were decreased in both group 1 and group 2 compared with control. Double support decreased in group 2 compared with control significantly(p<.05). In contrast to our hypothesis, there was no significant difference between group 1 and group 2. In Kinematics, we observed significant difference (p<.05) of decreased knee flexion in loading response (G2