• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.345-353
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• 2010

The purpose of this study was to compare and biomechanical evaluate the effects of three varying functional insoles on the kinematics of the lower extremities and foot pressure distribution during gait. For this 12 subjects participated in this study and each worn the 3 functional insoles during gait which kinematics, kinetics, electromyography and foot pressures were recorded. The function on the first insole was to absorb shock and increase the dynamic stability, the second was a gel type to absorb shock, and the third was to massage the center regions of the foot sole. the results were as follows; the first insole reduced the joints range of motion and reduced muscular fatigue, the second insole reduce the maximum, total and average foot pressures. Finally, the third insole produced larger values for the contact times and contact area.

• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.318-325
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• 2019

NREX, an upper limb exoskeleton robot, was developed at the National Rehabilitation Center to assist in the upper limb movements of subjects with weak muscular strength and control ability of the upper limbs, such as those with hemiplegia. For the free movement of the shoulder of the existing NREX, three passive joints were added, which improved its wearability. For the flexion/extension movement and internal/external rotation movement of the shoulder of the robot, the ball lock pin is used to fix or rotate the passive joint. The force and torque between a human and a robot were measured and analyzed in a reaching movement for four targets using a six-axis force/torque sensor for 20 able-bodied subjects. The addition of two passive joints to allow the user to rotate the shoulder can confirm that the average force of the upper limb must be 31.6% less and the torque must be 48.9% less to perform the movement related to the axis of rotation.

• Journal of Korean Neurosurgical Society
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• v.66 no.6
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• pp.611-617
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• 2023

The cervical spine plays a critical role in supporting the skull, maintaining horizontal gaze, and facilitating walking. Its unique characteristics, including the widest range of motion among spinal segments, have led to extensive research on cervical sagittal alignment. Various parameters have been proposed to evaluate cervical alignment, with studies investigating their clinical significance, correlation with symptoms, and implications for surgical interventions. Recent findings suggest that cervical sagittal alignment not only impacts the cervical spine but also influences global spine-pelvic alignment through compensatory mechanisms. This comprehensive review examines classical and new parameters of cervical sagittal alignment and considers the dynamic and muscular factors associated with it.

• Journal of Oral Medicine and Pain
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• v.37 no.3
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• pp.183-188
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• 2012

Previous studies of the relationship of TMJ signs and symptoms in elderly people have provided inconsistent findings. The objective of this study was to retrospectively analyze the prevalence of signs and symptoms of temporomandibular disorders(TMD). Additionally, young subjects were examined as a control group. Forty old patients (28 female, 12 male, mean age: $65.2{\pm}2.5$ years) and forty young patients (30 female, 10 male, mean age: $23.3{\pm}2.6$ years) clinically diagnosed with TMD were screened. Patient records were analyzed regarding: pain on chief complain, amount of range of mouth opening, TMJ noises(clicking sounds, crepitus), pain on palpation of the TMJ and masticatory muscles and neck and upper back muscles. Differences between the groups were assessed using t-test and the chi-squared test. (SPSS v.17) P value <0.05 was considered statistically significant. Geriatric subjects more often exhibited crepitus on mouth opening (25%), muscular palpation pain of masseter muscles (82.5%) and temporal muscles(60%). In contrast, young subjects more frequently exhibited joint sounds (62.5%), more amount of range of passive mouth opening (p=0.043). It was found that the younger subjects (82.5%) and the older subjects (87.5%) suffered from subjective sign (orofacial pain on chief complain). There were not statistically significant relationships between orofacial pain (VAS) and the groups. Differences between the groups with respect to joint sounds, muscular palpation pain and mandibular range of motion were significant. Although older subjects more frequently exhibited objective signs (crepitus on opening, pain on muscular palpation) of TMD, younger subjects more frequently objective signs (clicking sound on mouth opening, amount of mandibular range of motion).

• Journal of Biomedical Engineering Research
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• v.34 no.3
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• pp.148-155
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• 2013

This study is about the development of the wrist rehabilitation system for the patient who has limited capability of movement after stroke. Electromyography triggered training system (ETTS) can play the role between complete passive training and patient activating training system. Surface EMG was measured on pronator teres muscle and biceps brachii muscle for wrist pronation and supination. Our system detects whether the subject makes muscular effort for pronation or supination or nothing in every 50 ms. When the effort level exceeds the preset percentage of maximal voluntary contraction, the motor rotates according to the direction of the intention of the subject. EMG triggers the motor rotation for the wrist rehabilitation training until the preset angle. To evaluate its performance, the maximum voluntary contraction level was measured for 4 subjects at first. With the audio-visual instruction to rotate the wrist (pronation or supination) the subjects made effort to follow the instruction. After calculating root mean square (RMS) for 50 ms, the controller determines whether there was muscular effort to rotate while holding the motor. When there was an effort to rotate, the controller rotates the motor 0.8 degree. By comparing the RMS values from two channels of EMG, the controller determines the rotational direction. The onset delay is $0.76{\pm}0.24$ s and offset delay is $0.65{\pm}0.22$ s for pronation. For supination the onset delay is $1.24{\pm}0.41$ s and offset delay is $0.77{\pm}0.22$ s. The system responded fast enough to be used for rehabilitation training. The controller perceived the direction of rotation 100% correctly for the pronation and 97.5% correctly for supination. ETTS was developed and the fundamental functions were validated for normal subjects. The clinical validation should be done with patients for real world application. With ETTS, the subjects can train voluntarily over the limitation of the range of motion which increases the effectiveness of the rehabilitation training.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.4
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• pp.21-30
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• 2017

Purpose : This research intends to identify the effects of game-based weight bearing exercises on balance, muscular activation, sit to stand to sit motions of stroke patients. Method : 30 patients who were diagnosed as hemiplegia by stroke less in than a year were sampled and they were classified into two group, one of which was game-based weight bearing balance exercise group, and the other was functional weight bearing exercise group. 15 people were randomly selected for each group. Each exercise was coordinated by this research for 8 weeks, 5 days a week. 3D motion analyzer was used to measure the sit to stand to sit motions and a stopwatch was used to measure the time for stand-up motions for 5 times. Result : In terms of analyzing sit to stand to sit motions by phases, game-based weight bearing balance exercise group showed significant reduction compared to functional weight-bearing exercise group in phase I, II, III, IV and total time. In terms of functional stand-up performance analysis, game-based weight bearing balance exercise group showed significant reduction compared to functional weight-bearing exercise group in 5 times stand-up examination. Conclusion : It was verified that game-based weight bearing balance exercise had positive impact on function recovery of stroke patients by enhancing sit to stand to sit capabilities. It is considered that game-based exercise was an effective intermediary for functional improvement of stroke patients, while also inducing consistent and voluntary participation by causing interest and motivation.

• Physical Therapy Korea
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• v.23 no.1
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• pp.80-86
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• 2016

Background: Prone hip extension (PHE) can be performed to measure the lumbopelvic motor patterns and motions. Imbalances in lumbopelvic muscle activity and muscle weakness can result in instability including pain in lumbopelvic region. The posterior oblique sling (POS) muscles contribute to dynamic lumbopelvic stability. In addition, POS are anatomically aligned with the trapezius muscle group according to shoulder positions. Objects: This study compared the electromyography (EMG) activity of POS and pelvic compensations during PHE with and without pre-activation of lower trapezius muscle (lowT). Methods: Sixteen healthy males were recruited. PHE was performed in randomized order: PHE with and without lowT pre-activation. Surface EMG signals were recorded for biceps femoris (BF), gluteus maximus (GM) (ipsilateral), lumbar multifidus (MF) (bilateral), and the lowT (contralateral). An electromagnetic tracking motion analysis was used to measure the angle of pelvic rotation and anterior tilting. Results: The ipsilateral GM and bilateral MF EMG amplitudes were greater during PHE with lowT pre-activation compared to PHE without lowT pre-activation (p<.05). The BF amplitude during PHE without lowT pre-activation was significantly greater than that during PHE with lowT pre-activation (p<.05). The angles of pelvic rotation and anterior tilting during PHE with lowT pre-activation were significantly smaller compared to PHE without lowT pre-activation (p<.05). Conclusion: PHE with lowT pre-activation, which is aligned with the POS, showed more increased MF and GM muscular activity with smaller lumbopelvic compensations in rotation and anterior tilting compared to PHE without lowT pre-activation.

• Journal of Society of Preventive Korean Medicine
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• v.18 no.2
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• pp.115-123
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• 2014

Objective : The objective of this study is to develop a Qigong exercise program to reinforce musculoskeletal system of seniors appropriate for physical strength and conditions of seniors aged 65 years or above based on health Qigong exercise of oriental medicine. Method : Qigong exercise motions that can improve strength, muscular endurance, flexibility, and cardiovascular endurance of seniors were developed by primarily performing literature review of Qigong experts on the fields like oriental medicine, Qigong exercise, physical education and health science and secondarily using motion training for increased validity of motions. Results : The Qigong exercise program for musculoskeletal system of seniors was designed with 12 motions repeated 8 times and 20 minutes per session, including shoulder exercises (alternate turning of left and right shoulders, turning both arms back and forth, holding and lifting elbow to put it aside), waist exercises (wrapping the head with hands to bow, twisting waist while looking at the tip of hand, large spinning of ball, putting hands together to pull back), and knee exercises (going up a down while lifting a rock, balancing the body while lifting a knee, lifting and spreading knees while drawing circle with arms, raising both arms to the side while lifting heels, breathing). Conclusion : Once the effects of Qigong exercise for musculoskeletal system of seniors developed in this study are tested, the program is expected to contribute to development of Qigong exercise, a core part of oriental medicine health improvement project.

• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.265-276
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• 2003

The objective of this research is to provide basic data for improving athletic performances, suggesting methods that can be utilized at games and coaching movements in the snatch, by analyzing the level of contribution of muscles to the movements of the snatch lift through three-dimensional imaging and EMG analysis between skilled and unskilled lifters. To this end, three high school students (the skilled group), three middle school student (the unskilled group) were selected; two digital video cameras and electromyography were used. The muscles measured by an EMG include gastrocnemius muscle, biceps femoris muscle, erector spinae, latissimus dorsi muscle, trapezius muscle, and brachioradialis. Based on the Ariel Performance Analysis System (APAS) program, the results of the analysis are summarized as follows. 1. In performing snatch pulls, the skilled lifters were found to simultaneously move the weight centers of the body and the barbell close to vertical, close to the shoulders in the pulling portion; in snatching and grabbing the barbell from a sited position, it was observed that the shorter the time for adjusting to change in the height of the barbell by using rotational inertia, the better it is to perform the movements. 2. The skilled lifters were observed to perform stable and efficient movements in grabbing the bar in a sited position, by moving the barbell and weight center of the body close to vertical and moving the shoulder joint under the bar fast. 3. The results of the EMG analysis of the entire movements from the snatching portion to the portion of grabbing the bar in a sited position show that when the skilled lifters lifted the barbell vertically during the pulling portion, their shoulder joints were extended to put more weight on biceps femoris muscle and brachioradialis; and in snatching and grabbing the bar from a sited position, it was found desirable to increase the myoelectrical activity of erector spinae in order to achieve a balance in the movements of the hip joint between font and rear, as the weight centers of the body and the barbell move higher. On the other hand, the unskilled lifters were found that in response to change in posture, they increase their muscular strength inefficiently in performing the movements throughout the entire lifting process.

• Journal of the Korean Arthroscopy Society
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• v.5 no.1
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• pp.41-44
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• 2001

The muscular button holing of vastus medialis is a very rare case of irreducible knee dislocations, and rapid reduction of this can diminish the complications which delayed reduction accompanies. We diagnosed a patient who appeared posterolateral dislocation of the knee and protrusion of the medial femoral condyle with MRI grossly. That was reduced by open arthrotomy, followed the reconstruction of both cruciate ligaments and repair of medial collateral ligament. Patient didn't show joint instability except minor posterior sagging and had full range of motion postoperatively after 10 months.