• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.145-151
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• 2006

A large interindividual variability and some abnormally kinematic patterns at the lower extremity were the main features of the gait in children with Down syndrome. The purposes of this study were to investigate the gait asymmetry and biomechanical difference between dominant leg and non dominant leg in children with Down syndrome. Seven boys with Down Syndrome(age: $120{\pm}0.9yrs$, weight $34.4{\pm}8.4kg$, leg length: $68.7{\pm}5.0cm$) participated in this study. A 10.0 m ${\times}$ 1.3 m walkway with a firm dark surface was built and used for data collection. Three-dimensional motion analyses were performed to obtain the joint angles and range of motions. The vertical ground reaction forces(%BW) and impulses($%BW{\cdot}s$) were measured by two force plates embedded in the walkway. Asymmetry indices between the legs were computed for all variables. After decision the dominant leg and the non dominant leg with max hip abduction angle, paired samples t-test was employed for selected kinematic and ground reaction force variables to analyze the differences between the dominant leg and the non dominant leg. The max hip abduction angle during the swing phase showed most asymmetry, while the knee flexion angle at initial contact showed most symmetry in walking and running. The dominant leg showed more excessive abduction of hip in the swing phase and more flat-footed contact than the non dominant leg. Vertical peak force in running showed more larger than those of in walking, however, vertical impulse showed more small than walking due to decrease of support time. In conclusion, the foot of dominant leg contact more carefully than those of non dominant leg. And also, there are no significant difference between the dominant leg and the non dominant leg in kinematic variables and ground reaction force due to large interindividual variability.

• The Journal of Korean Physical Therapy
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• v.21 no.1
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• pp.49-55
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• 2009

Purpose: The purpose of this study was to evaluate influence of contract-relax exercise on functional leg length inequality (FLLI) and muscle activity. Methods: The subjects were consisted of 40 healthy adults who had FLLI of which degree was at least 10mm. All subjects were randomly assigned to two groups : Contract-Relax Exercise (CRE) group (n=20), control group (n=20). The experimental group underwent CRE for 3 times a week for 4 weeks. Myosystem 1200 was used to measure the activity of rectus femoris and hamstring muscle. The tape measure method was used to measure FLLI. Statistical analysis was used repeated ANOVA know comparison of period, independent T-est know comparison of experiment group and control group. Results: All measurements for each subject took the following test : pre-test, post-test in 2 weeks, post-test in 4 weeks. The FLLI of the experimental group was significantly reduced according to within intervention period (p<0.05). Rectus femoris and hamstring muscle activity of the experimental group was significantly increased (p<0.05). Conclusion: The CRE can reduce FLLI and increase rectus femoris and hamstring muscle activity. Various contract-relax exercise for reduced of FLLI and the methods should be customized for the patients.

• Journal of Welding and Joining
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• v.32 no.1
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• pp.79-86
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• 2014

The purpose of this study is to determine the proper fillet weld size for the stiffeners on hull bottom plate of crude oil tanker. To achieve it, the effective notch stress and hot spot stress of the fillet weld with leg length specified in the rule were evaluated by using comprehensive FE analyses. Based on the results, the fatigue damages at each location of weld were calculated. Meanwhile the transitional behavior of initial welding distortion in the hull bottom plate under the design conditions was investigated by using a non-linear FEA. Welding distortion and residual stress introduced during fabrication process were considered as initial imperfections. According to FE analysis results, if the fillet leg length satisfies the design criteria of the classification society, the concern on the root failure at the fillet welds in the bottom hull plate during the design life can be negligible. In addition, considering the transitional behavior of the distortion during the service life, the fillet leg length should be minimized.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.2
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• pp.59-67
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• 2019

Purpose : The purpose of this study was to analyze the dynamic range of motion (ROM) of pelvic and translation of center of mass (COM) when wearing different shoe insole lifts according to leg length discrepancy (LLD) during free speed gait. Methods : Thirty-five healthy adults were participated in this study. Kinematic data were collected using a Vicon motion capture system. Reflective and cluster 40 markers attached to participants lower extremities and were asked to walk in a 6 m gait way under three different shoe lift conditions (without any insole, 1 cm insole, and 2 cm insole). The pelvic ROM and COM translation in three planes were sorted using a Nexus software, and a Visual3D motion analysis software was used to coordinate all kinematic data. Results : There were significantly increased maximal pelvic elevation and total pelvic range in coronal plane when wearing a standard shoe with 2 cm insole lift during gait (p<.05). When wearing a standard shoe with 2 cm insole lift, the total range of the pelvic segment were significantly different in all three motion planes (p<.05). Conclusion : Although LLD of less than 2 cm develops abnormal movement pattern of the pelvis and may cause of musculoskeletal diseases such as low back pain, hip and knee joint osteoarthritis, therefore intensive various physical therapy interventions for LLD are needed.

• PNF and Movement
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• v.20 no.1
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• pp.59-66
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• 2022

Purpose: The aim of this research was to verify the relationship between three-dimensional (3D) ground reaction force (GRF) and severity of leg length discrepancy (LLD) while walking at a normal speed. It used a 3D motion analysis system with force platforms in standing workers with LLD. Methods: Subjects comprising 45 standing workers with LLD were selected. Two force platforms were used to acquire 3D GRF data based on a motion analysis system during gait. Vicon Nexus and Visual3D v6 Professional software were used to analyze kinetic GRF data. The subjects were asked to walk on a walkway with 40 infrared reflective markers attached to their lower extremities to collect 3D GRF data. Results: The results indicated the maximal force in the posterior and lateral direction of the long limb occurring in the early stance phase during gait had significant positive correlation with LLD severity (r = 0.664~0.738, p <0.01). In addition, the maximal force medial direction of the long limb occurring in the late stance phase showed a highly positive correlation with the LLD measurement (r = 0.527, p <0.01). Conclusion: Our results indicate that greater measured LLD severity results in more plantar pressure occurring in the foot area during heel contact to loading response of the stance phase and the stance push-off period during gait.

• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.55-63
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• 2002

Human body balances right and left leg centering around pelvis and spine. Therefore, imbalance of lower extremity means disequilibrium of the body. The difference of lower extremity length can cause a number of clinic symptoms including scoliosis, low back pain, sacroiliac pain, and sports injury. In this study, we tried to analyze low back pain and joint stiffness resulting from the difference of lower extremity length. The subjects were 80 male students who are 20-25 years old. The results of this study were as following: 1. Low back pain depending on the difference of lower extremity length One group which the difference of lower extremity length is above 12mm showed average different length as 18.0mm, the other group which one is below 12mm showed as 6.3mm. A group of above 12mm had more severe low back pain than a group of below 12mm. 2. Joint stiffness depending on the difference of lower extremity length A group of above 12mm had more severe joint stiffness than a group of below 12mm.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.19 no.1
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• pp.55-61
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• 2013

Background: The purpose of this study was to investigate the immediate effects of mulligan's straight leg raise with traction technique on angle of passive straight leg raise and length of hamstring muscle in patients with low back and radiate pain. Methods: Thirty one subjects participated in this study. The subjects were assigned to either the low back pain group (n=17) or the radiate pain group (n=14). Subjects in both groups received 3 times mulligan's straight leg raise with traction. All subjects were examined for the range of motion of lower extremity. The range of motion of lower extremity was composed of angle on straight leg raise and 90-90 straight leg raise. The range of motion of lower extremity was measured using a goniometer. Results: After 3 times of mulligan's straight leg raise with traction, significant improvements on the angle of straight leg raise and 90-90 straight leg raise were observed in the both groups (p<.05). However, there are no significant difference was observed between groups. Conclusion: These results suggest that mulligan's straight leg raise with traction provides an immediately effective in range of motion of lower extremity in patients with low back pain as well as radiate pain. Although more research is required on the effects of long-term mulligan's straight leg raise with traction on range of motion of lower extremity, our results can be useful to establish the standard parameters for range of motion of lower extremity in the clinical setting.

• Physical Therapy Rehabilitation Science
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• v.8 no.3
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• pp.141-145
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• 2019

Objective: The purpose of this study was to compare walking conditions (straight line and curved path) on walking patterns in persons who had experienced hemiplegic stroke and to determine whether if they adapt their walking pattern and performances according to changes in environmental conditions. Design: Cross-sectional study. Methods: Forty-four hemiplegic stroke survivors participated in this study. This study measured walking performance in three different walking conditions, such as straight walking, the more-affected leg in the inner curve walking, and less-affected leg in the inner curve walking conditions, and a 2-dimentional gait analysis system was used as a primary measurement. This study also measured secondary clinical factors including the Timed Up-and-Go Test, the Trunk Impairment Scale, and the Dynamic Gait Index. Results: After analyzing, cadence and step length of the less-affected side, stride length in the more-affected side, and stride length in less-affected side were significantly different among the three different walking conditions in this study (p<0.05), but other temporospatial parameters were not significant. Cadence was the largest in the straight walking condition. Step length in the less-affected side, stride length in the more-affected side, and stride length in less-affected side were also the longest in the straight walking condition. Conclusions: The results of the study suggest that hemiplegic stroke survivors show walking adaptability according to changes in walking demands and conditions, and moreover, cadence and step and stride lengths were significantly different between straight and curved walking conditions.

• Animal Systematics, Evolution and Diversity
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• v.32 no.1
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• pp.9-20
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• 2016

Two new species of poecilostomatoid copepods associated with echiurans are described from an intertidal mud flat in the Yellow Sea. A new genus Echiuricopus is created to accommodate two new species, E. aprilis and E. tenuipes. Major differences between the two new species are displayed in body length, length of caudal ramus seta I, length/width ratio of leg 5 exopod, and armature of the first antennular segment. Echiuricopus n. gen. is closely related to the genus Goidelia Embleton, 1901, but is distinguished from the latter chiefly by having seven caudal setae, a claw-like process on the first antennular segment, one claw-like process on the maxillary syncoxa, the absence of an inner coxal seta on legs 1-4, different armatures on legs 1-4, and an elongate leg 5 exopod.

• Journal of Acupuncture Research
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• v.34 no.4
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• pp.185-189
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• 2017

Background: The aim of this study was to assess the change in radiating leg pain after traffic accidents in patients with and without herniated intervertebral disc (HIVD) and improvement of radiating leg pain after traffic accidents. Methods: This was an retrospective study of 188 patients. Patients who had been admitted to the Hospital of Korean Medicine with the complaint of radiating leg pain after traffic accidents, and who had undergone lumbar spine magnetic resonance imaging to determine the presence or absence of HIVD were observed from April to June 2016. We analyzed sex, age, length of admission, direction (to a single leg or to both legs) and locations, (medial, anterior, lateral or posterior side of the lower limb) of radiating leg pain, presence or absence of HIVD, and number, grade and position of HIVD. The Numeric Rating Scale (NRS) and Oswestry Disability Index (ODI) were used to evaluate the impact of radiating leg pain on patients. Results: Radiating leg pain NRS score decreased significantly in both the HIVD group (from $6.12{\pm}2.39$ to $4.31{\pm}1.87$, p < 0.001) and the no HIVD group (from $5.76{\pm}1.64$ to $3.85{\pm}1.41$, p < 0.001). ODI score also decreased significantly in both groups (HIVD, from $44.67{\pm}17.38$ to $26.83{\pm}13.18$; no HIVD, from $39.24{\pm}15.58$ to $19.69{\pm}12$.; both p < 0.001). Conclusion: There was no significant change in radiating leg pain after traffic accidents in patients with and without HIVD and improvement of radiating leg pain after traffic accidents.