• Journal of the Ergonomics Society of Korea
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• v.29 no.1
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• pp.73-82
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• 2010

The purpose of this study is to understand motion characteristics of older drivers during reaching seat belt compared to young drivers and to provide design guidelines in order to reduce discomfort for the elderly. The whole body kinematics of each subject was captured using 12-camera motion analysis system. Subjective ratings on discomfort levels were obtained simultaneously using a questionnaire. This paper first presents the result of motion characteristics of elderly drivers' reach motion to seat belt. Compared to young drivers, older drivers performed seat belt reach motions less efficiently and moved slower due to mostly the movement error. Older drivers also made use of reduced joint range of motion in cervical left rotation, lumbar left rotation and right shoulder adduction, which can be explained by their reduced active range of motions (AROMs). To compensate for their reduced joint range of motion, older drivers rotated pelvis more.

• Journal of the Ergonomics Society of Korea
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• v.32 no.3
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• pp.245-252
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• 2013

Objective: This paper analyzes the changes on stride parameters, joint angles, and trajectories of the body parts due to high heels during walking and explains the causal relationship between the changes and high heels. Background: This study aims to indicate the comprehensive gait changes by high heels on the whole body for women wearing high heels and researchers interested in high-heeled walking. Method: The experiment was designed in which two different shoe heel heights were used for walking (1cm, 9.8cm), and twelve women participated in the test. In the experiment, 35 points on the body were tracked to extract the stride parameters, joint angles, and trajectories of the body parts. Results: Double support time increased, but stride length decreased in high-heeled walking. The knee inflexed more at stance phase and the spine rotation became more severe. The trajectories of the pelvis, the trunk and the head presented outstanding fluctuations in the vertical direction. Conclusion: The double support time and the spine rotation were changed to compensate instability by high heels. Reduced range of motion of the ankle joint influenced on the stride length, the knee flexion, and fluctuations of the body parts. Application: This study can provide an insight of the gait changes by high heels through the entire body.

• Korean Journal of Applied Biomechanics
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• v.32 no.4
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• pp.147-152
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• 2022

Objective: The purpose of this study was to analyze the effects of club head and golf ball kinematics and body alignment according to the swing plane during golf driver swing. Method: Sixteen college golfers participated in this study. Kinematic data of the club head and golf ball were collected using golf swing analysis system (Trackman Ver. 3e). The body alignment variables were collected using 8 motion capture system. An Independent samples t-test was used for comparison between the Out-to-In group and In-to-Out group, and the statistical significance level was set at .05. Results: For the club head related variables, club path and club face angle showed higher values in Out-to-In swing plane than In-to-Out swing plane. For the kinematic variables of the golf ball, the total distance showed a higher value in the In-to-Out swing plane than that of the Out-to-In swing plane. For the body alignment, the In-to-Out swing plane showed higher values than the Out-to-In swing plane for the pelvis rotation angle and trunk rotation angle. Conclusion: This study suggest that it would be more effective to use the In-to-Out swing plane for increasing the total distance during the golf driver swing.

• Physical Therapy Korea
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• v.19 no.4
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• pp.46-54
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• 2012

Ely's test is commonly used to assess rectus femoris muscle flexibility. however, a reliability limit of this test was demonstrated by a previous study. In this study, we present an alternative method using an application for a digital horizontal level in a smartphone (DHLS) to complement the reliability limit of Ely's test. The aim of this study was to examine the reliability of Ely's test using DHLS on the pelvis, compared to using visual observation (VO) of pelvic and hip motions. Nineteen patients with lumbar extension-rotation syndrome were recruited for this study. An examiner examined the rectus femoris flexibility (both pass/fail and goniometer scoring) through Ely's test using both DHLS and VO. A retest session was completed two hours later for within-day reliability and seven days later for between-day intra-rater test-retest reliability. Results showed higher Kappa values for pass/fail scoring and higher intraclass correlation coefficient values for goniometer scoring in Ely's test using DHLS, compared to using VO. Measurement error and Bland and Altman plots further demonstrated the degree of intra-rater variance during Ely's test using DHLS in a clinical setting, compared to using VO. These results demonstrated that Ely's test using DHLS showed acceptable reliability compared to using VO. Ely's test using DHLS could be widely used for measuring the rectus femoris muscle flexibility in patients with lumbar extension-rotation syndrome, although the inter-rater reliability needs to be established first.

• Journal of Korean Medicine Rehabilitation
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• v.32 no.2
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• pp.83-94
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• 2022

Objectives This systematic review aimed to analyze research about pelvic deviation diagnosis for Chuna manual therapy (CMT) and to review the diagnosis methods, indices, and results of diagnosis. Methods Ten electronic databases were systematically searched up to January 4th 2022. Clinical studies and reviews containing pelvic deviation diagnosis for CMT or using CMT as a treatment of pelvic deviation were selected and evaluated. CMT diagnosis in clinical studies and reviews were isolated and analyzed by 2 independent reviewers. Results Thirteen clinical studies and three reviews were included in the evaluation. X-ray analysis and manual testing were the two main methods used in CMT diagnosis of pelvic deviation. For manual testing in clinical studies, leg length insufficiency testing was the most frequently used measurement index and the most common diagnostic results were anterior and posterior rotation. In the X-ray analysis, Obturator foramen and femur head line were the most frequently used measurement index and the most common diagnostic results were anterior rotation and posterior rotation. Conclusions The systematic review found that manual testing and X-ray analysis were mainly used for the diagnosis of pelvic deviation in CMT among clincial and review articles. As there was little research about diagnosing pelvic deviation in CMT and any existing research presented only low standards of evidence, further research should be updated with using a more standardized approach.

• The Journal of Korean Physical Therapy
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• v.10 no.1
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• pp.213-221
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• 1998

The purpose of this study was a motion analysis of proprioceptive neuromuscular facilitation patterns which is scapular and pelvis patterns, upper extremity patterns, lower extremity patterns, trunk patterns. The patterns combine motion in sagittal plane for flextion and extension, coronal or frontal plane for abduction and adduction, transverse plane for rotation. The patterns composed of mass movement pattern of the limbs and trunk muscles. Every pattern can change by changing the activity of the middle joint in the extremity patterns and changing the patient's positions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1154-1159
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• 2004

Unexpected postoperative changes, such as growth in rib hump, has been occasionally reported after corrective surgery for scoliosis. However there has been experimental data for explanation of these changes, nor the suggestion of optimal correction method. This numerical study was designed to investigate the main correlating elements in operative kinematics with post-operative changes of vertebral rotation and rib cage deformation in the corrective surgery of scoliosis. To develop a scoliotic spine model automatically, a special program for converting normal spine model to scoliotic spine model was developed. A mathematical finite element model of normal spine including rib cage, sternum, both clavicles, and pelvis was developed with anatomical details. The skeletal deformity of scoliosis was reconstructed, by mapping the X-ray images of a scoliosis into this three dimensional normal spine and rib cage model. The geometric mapping was performed by translating and rotating the spinal colume with the amount analyzed from the digitized 12 built-in coordinate axes in each vertebral image. By utilizing this program, problems generated in mapping procedure such as facet joint overlapping, vertebral body deformity could be automatically resolved.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.769-776
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• 2001

This study were to review of muscle imbalance of head, cervical and shoulder region. Head, cervical and shoulder region is a complicated mechanical unit. interconnected by numerous soft tissue links. These links, or articulation are functionaly and reflexly interdependent on one another. The line of gravity falls anterior to the transverse axis of rotation for flexion and extension of the head and creates a flexion moment. which tends to tut the head forward, is counteracted by tension in the tectorial membrane, and ligamentum nuchae, and by activity of the neck extensors. Therefore, the flexion moment equilibrate with the extension moment. Changing of the equilibrium will make mid cervical straight. It will make forward head posture(FHP) also. FHP makes imbalance of suboccipital muscles, suprahyoid muscles and infrahyoid muscles. It has some relationship with temporomandibular joint, spine and equilibrium of pelvis.

• Proceedings of the Korean Society of Computer Information Conference
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• 2018.01a
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• pp.55-56
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• 2018

Subjects will flex and extend their knees in a prone posture while keeping the pelvis in a neutral state after having straightened the knees and hip. The angle of the manual measurement of an average person when bent is between $110^{\circ}{\sim}135^{\circ}$. If the person complains of pain at the time of flexion, it signifies the presence of abnormality in the knee joints and muscles. The number and proportion of the patients were measured through this experiment.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.3
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• pp.79-85
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• 2013

Objectives The aim of this study was to investigate pelvic insufficiency and its correlation with lumbago side. Methods 72 cases of patients who received treatment from March 2010 to February 2013 for lumbago were analyzed. Their pelvic insufficiency parameters were estimated by x-ray analysis and lumbago sides were considered. The data were analyzed to find out correlation of pelvic insufficiency parameters and correlation between parameters and lumbago sides. Pearson correlation and two-by-k cross tabulation analysis were used. Results 1) Iliac height difference had significant correlation with femur height difference and the result was alike previous studies' results. 2) Femur height difference and iliac height difference had no significant correlation with iliac width difference. 3) Posterior rotation malposition ilium side and inflare side had no significant correlation with lumbago side. Conclusions Iliac height difference had significant correlation with femur height difference and sides of pelvic insufficiency had no significant correlation with lumbago sides.