• Korean Journal of Applied Biomechanics
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• v.21 no.2
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• pp.189-196
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• 2011

The purpose of this study was to verify the difference in biomechanical variation and pattern of the lower limb between planned and unexpected termination, which is related to the prevention of fatal fall in the elderly. Therefore, selected twenty subjects for each group which composed of females(age: $73.5{\pm}4.63$ year, height: $153.2{\pm}6.46$ cm, body mass: $58.98{\pm}5.82$ kg) and women(age: $23.4{\pm}2.5$ year, height: $164.65{\pm}3.9$ cm, body mass: $58.47{\pm}5.53$ kg) in their twenties. As a result, lower limb's extension moment and power were increased significantly in statistics(p<.05). Also, knee joint power showed instant changes from concentric contraction to eccentric contraction and hip joint power from eccentric contraction to concentric contraction. During unexpected termination there were dramatical increase in eccentric contraction and power(p<.05). In both planned and unexpected termination, ankle joint moment were higher in young group, but the moment of the hip joint were higher in the elderly group(p<.05). In contrast to younger group, there were no changes in knee extension moment in elderly group(p<.05). but showed relatively higher hip joint extension moment and power(p<.05).

• Journal of Biomedical Engineering Research
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• v.15 no.4
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• pp.429-438
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• 1994

An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate eleclromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocnemius m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher'stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical slimulator restored partially gait function in paraplegic patients.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.7 s.172
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• pp.112-121
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• 2005

This paper is concerned with smooth trajectory generation of biped robot which has inverted pendulum type balancing weight. Genetic algorithm is used to generate the trajectory of the leg and balancing weight. Balancing trajectory can be determined by solving the second order differential equation under the condition that the reference ZMP (Zero moment point) is settled. Reference ZMP effect on gait pattern absolutely but the problem is how to determine the reference ZMP. Genetic algorithm can find optimal solution under the high order nonlinear situation. Optimal trajectory is generated when use genetic algorithm which has some genes and a fitness function. In this paper, minimization of balancing joints motion is used for the fitness function and set the weight factor of the two balancing joints at the fitness function. Inverted pendulum type balancing weight is very similar with human and this model can be used fur humanoid robot. Simulation results show ZMP trajectory and the walking experiment made on the real biped robot IWR-IV.

• The Journal of Korean Physical Therapy
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• v.11 no.3
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• pp.151-158
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• 1999

Neuropathy is a common and often debilitating complication of diabetes, Diabetic peripheral neuropathy(DN) includes a variety of different disorders that affect the peripheral nervous system. The most common type of DN is the predominantly sensory distal polyneuropathy. Typically, symptoms begin in the foot and proximally during the course of the discease, reflecting the fact that longer fibres are involved earlier that shorter ones. Reviewed the pathogenesis, the diagnosis of DN, the gait pattern and the excercise, the treatment of pain in DN patient.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.8
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• pp.506-509
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• 2003

This paper describes the possibility of analyzing gait pattern from the changes of the lower leg electrical impedance. This impedance was measured by the four-electrode method. Two current electrodes were applied to the thigh, knee, and foot., and two potential electrodes were applied to the lateral, medial, and posterior position of human leg. The correlation coefficients of the joint angle and the impedance change from human leg movement was obtained using a electrogoniometer and 4ch impedance measurement system developed in this study. We found the optimal electrode position for knee and ankle joint movements based on high correlation coefficient, least interference, and maximum magnitude of impedance change. The correlation coefficients of the ankle, knee, and the hip movements were -0.913, 0.984 and 0.823, respectively. From such features of the human leg impedance, it has been made clear that different movement patterns exhibit different impedance patterns and impedance level. This system showed feasibility that lower leg movement could be easily measured by impedance measurement system with a few skin-electrodes.

• Korean Journal of Applied Biomechanics
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• v.13 no.1
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• pp.109-119
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• 2003

The purpose of this study was to investigate differences of the mechanical efficiency on the characteristics of the basketball wheelchairs(cambers & size of the handrims). Nine healthy and normal wheelchair basketball players who had no impairments to their upper extremities were volunteered to participate in this study. $VO_2$ was collected using automatic gas analyzer(vmax29). Gross efficiency, net efficiency and work efficiency were analyzed from the calculated external power output and energy expenditure. The results were followed. First, gross efficiency in the basketball wheelchairs was observed across the range from 4 to 10%. Gross efficiency in this study showed less values than that from the literature reviewed in the arm cranking(15%), racing wheelchair(above 30%), gait(27%) and cycling(18-23%). Second, the small size of handrim(61cm) at the 16 degrees of camber produced higher efficiency values than the large size of handrim(66cm) whereas the different sizes of handrim at the 20 degrees of camber did not show any pattern. Third, both faster speed($1.11^m/s{\rightarrow}1.39^m/s$) and increases in treadmill inclination produced increases in energy expenditure. The results of this study may provide not only better understanding of the mechanical efficiency with adequate camber degree and proper size of handrim but also fundamental information for manufacturing the wheelchair.

• Journal of the Korean Society of Physical Medicine
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• v.3 no.3
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• pp.177-183
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• 2008

Purpose : The purpose of this study was to investigate characteristics of the muscle activities during level walking and stairs ascending in young adults. Methods : Fifteen young adult were recruited this study. Muscle activity (BIOPAC System Inc., Santa Barbara, U.SA). Statistical analysis was difference between level and stair walking. Results : In stance phase, muscle activity of low extremity generally more increased during ramp ascent both young adults. In swing phase, muscle activity of low extremity generally more increased during stairs ascent in young adults. Conclusion : These results indicate that stair and ramp ascent is more difficult task than level walking in young adults. Muscle activity was more changed at ramp ascent. In the future, we suggest that studies of stair and ramp gait pattern regarding ambulatory patient with disabilities be further studied and an appropriate stairs and ramp inclination will be indicated.

• Journal of The Korean Society of Integrative Medicine
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• v.2 no.1
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• pp.23-34
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• 2014

연구목적 : 본 연구의 목적은 8주간의 점진적인 속도증진 훈련이 뇌졸중환자의 족저압, 보행주기, 보행대칭성에 어떠한 영향을 주는지 알아보는 것이다. 연구방법 : 연구에 참여한 대상자들은 뇌졸중으로 진단 받고 N병원에 입원한 편마비환자 20명(실험군 10명, 대조군 10명)을 대상으로 하였다. 이들은 모두 물리치료와 작업치료를 받았고, 실험군은 주3회, 8주간의 트레드밀 보행훈련를 받았고, 대조군은 받지 않았다. 실험전, 후에 F-scan을 이용하여 보행주기, 보행대칭성을 검사하였다. 연구결과 : 8주 후, 보행주기는 실험군의 양하지지지기 I II, 단하지지지기에서 모두 유의하게 증가하였으나, 대조군에서는 양하지지지기 II, 단하지지지기에서 유의하게 증가하였다. 유각기는 실험군과 대조군 모두 유의하지는 않았다. 보행대칭성은 입각기 대칭성에서 대조군과 비교하여 실험군에서 유의하게 증가하였으나, 유각기 대칭성은 실험군과 대조군 모두 유의하지 않았다. 결론 : 뇌졸중 환자에 있어 보행훈련은 보행주기과 보행대칭성과 를 개선시키며, 특히 점진적인 속도 증진훈련은 양하지지지기, 단하지지지기, 입각기 보행대칭성에 효과적인 방법으로 사용될 수 있을 것으로 보인다.

• Journal of Yeungnam Medical Science
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• v.23 no.1
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• pp.118-123
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• 2006

Dentatorubropallidoluysian atrophy (DRPLA) is a rare neurodegenerative disorder usually inherited in an autosomal dominant pattern. DRPLA has been shown to be associated with expansion of an unstable cytosine-adenine-guanine (CAG) trinucleotide repeat in a gene on chromosome 12p. We evaluated a family with DRPLA that affected three members; A 35-year-old female presented with seven year history of gait ataxia, dysarthria and mild cognitive impairment. The MRI of the brain revealed diffuse cerebellar atrophy with an incidental lipoma in the midbrain. Her 30-year-old brother presented with progressive cerebellar ataxia that developed at the age of 20. Her grandmother and mother were reported to have developed ataxia during the late period of their life, and died at the age of 60 and 55, respectively. The demonstration of an expanded CAG repeat in the gene for DRPLA was used to confirm the diagnosis.

• Journal of Acupuncture Research
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• v.36 no.4
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• pp.282-285
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• 2019

Scoliosis is a 3-dimensional spinal deformity defined as lateral curvature of the spine in the coronal plane of more than $10^{\circ}$. This study describes a case of functional scoliosis after hip injury. In this case, the patient fell whilst inline skating (June 2015) causing severe tilting of her spine, and left hip pain. She received outpatient treatment from July 14, 2015 to December 28, 2015. For approximately 5 months, acupuncture therapy was performed to relax the tension in both hips, Chuna therapy, and foot orthosis were applied to reduce the body's imbalance. Based on X-ray images, the Cobb angle had decreased from $14.73^{\circ}$ (pretreatment) to $1.90^{\circ}$ (posttreatment). This case report suggested that Korean medicine treatment could be an effective therapeutic choice for functional scoliosis.