• The Journal of Korea Robotics Society
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• 제12권3호
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• pp.270-278
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• 2017

The electrical muscle stimulator (EMS) based human machine interface (HMI) free to mechanical constraint and muscle fatigue problems are proposed for force feedback in a virtual reality. The device was designed to provide force feedback up to 4.8 N and 2.6 N each to the thumb and forefingers. The main objective of the HMI is to make unnecessary mechanical structures to attach on the hand or fingers. It employs custom EMSs and an interface arranged in the forearm. In this work, major muscle groups such as extensor pollicis brevis (EPB), extensor indicis proprius (EIP), flexor pollicis longus (FPL) and flexor digitorum profundus (FDP) are selected for efficient force feedback and controlled individually. For this, a human muscular-skeletal analysis was performed and verified. The validity of the proposed multi-channel EMS based HMI was evaluated thorough various experiments with ten human subjects, interacting with a virtual environment.

• Physical Therapy Korea
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• 제13권1호
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• pp.32-37
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• 2006

The purpose of this study was to investigate the effects of clinical characteristics of chronic stroke patients on physiological cost index (PCI) during walking. Fourteen stroke patients participated in this study. To investigate the clinical characteristics, Fugl-Meyer score (FMS), gait velocity (GV), muscle strength of the knee extensor, modified Ashworth scale (MAS) of ankle plantar flexor, devices, and gait patterns during walking were measured and analyzed. The results were as follows: Firstly, use of devices and high MAS of the ankle plantar flexor significantly increased PCI. Secondly, PCI was significantly correlated with the FMS and MAS of the ankle plantar flexor. In conclusion, inhibition of spasticity of the ankle plantar flexor is considered to reduce PCI during walking for chronic stroke patients.

• Anatomy and Cell Biology
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• 제56권4호
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• pp.562-565
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• 2023

The muscles of the sole have been traditionally categorized into four layers, but it is more practical to divide them into peripheral and central groups. The peripheral groups include medial and lateral groups. The central plantar muscles are more numerous and divided into superficial and deep layers. During routine dissection in the Department of Anatomy, All India Institute of Medical Sciences Bibinagar, Hyderabad, variations are been observed in the plantar intrinsic muscle in the left foot & right foot of a 53-year-old male cadaver. This is the first cadaveric report of a combination of discrepancies especially the inter-tendinous connection between quadratus plantae and flexor digitorum brevis. Similar observations in the literature were not found by us. It is important to identify and study these dissimilarities of muscles of the sole for surgeons, anatomists, radiologists and orthopaedics as these muscles and tendons are used in foot reconstructive procedures, and for the treatment of some congenital anomalies.

• Korean Journal of Applied Biomechanics
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• 제24권1호
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• pp.35-42
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• 2014

Tendon elasticity is an important factor affecting muscle function and thus human movements. It has been reported that the mechanical properties of tendon are adaptable to external loading condition. Based on the adaptability of muscle and tendon to external loading conditions, one can assume that there might be an optimum ratio between muscle strength and tendon stiffness. The present study aimed to investigate whether there is correlation between plantar flexor muscle strength and stiffness of the achilles tendon (AT). Twenty two male subjects (age: $23.2{\pm}1.5yrs$, height: $175.5{\pm}6.2cm$, weight: $75.4{\pm}9.8kg$) performed maximum voluntary isometric plantarflexion on a custom-built dynamometer and muscle-tendon junction of the medial gastrocnemius muscle was simultaneously monitored using a real-time ultrasound imaging machine. The averages of muscle force and tendon stiffness were $366.38{\pm}79.37N$, $35.34{\pm}10.42N/mm$, respectively. Significant positive correlation was observed between muscle strength and tendon stiffness (r=0.8507), indicating that the muscle force is proportional to tendon stiffness. The results might have been used in computational modeling and criterion of training progress level in the fields of training and rehabilitation.

• Journal of the Korean Society of Physical Medicine
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• 제11권4호
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• pp.139-146
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• 2016

PURPOSE: The purpose of this study was to determine the effect of craniocervical flexion exercise with masticatory muscle contraction in patients with neck pain. Patients with neck pain also experience muscle weakness and limitation of activities of daily living. Craniocervical flexion exercise with masticatory muscle contraction may increase the thickness of the deep cervical flexor muscles, thereby reducing pain and limitations on activities of daily living. METHODS: Twenty-six volunteers participated in this study. The subjects were randomly divided into an experimental group (n=13) and a control group (n=13). Both groups performed craniocervical flexion exercise using a pressure biofeedback unit; the experimental group performed craniocervical flexion exercise with masticatory muscle contraction for 20 minutes, 3 times a week for 4 weeks. Assessment tools included ultrasonography for measurement of muscle thickness and the Neck Disability Index for the level of pain and function. RESULTS: The rate of change in muscle thickness in both groups significantly increased (p<.05), with a significantly greater increase in the experimental group than in the control group (p<.05). The Neck Disability Index score significantly improved (p<.05) in both groups, with significantly greater improvement in the experimental group compared with the control group (p<.05). CONCLUSION: These results suggest that craniocervical flexion exercise with masticatory muscle contraction can be effective in increasing muscle thickness and improving the Neck Disability Index score in patients with neck pain.

• Physical Therapy Rehabilitation Science
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• 제10권2호
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• pp.156-160
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• 2021

Objective: Low back pain easily becomes chronic and has a high recurrence rate. Therefore, it is most important to prevent chronicity and reduce the risk of recurrence in the early stages of back pain or at the stage with mild pain. Therefore, this study was conducted to compare hip joint muscle strength, trunk muscle endurance, and pelvic alignment between subjects with mild low back pain and subjects without back pain. Design: Crossed-sectional study Methods: The study was conducted by recruiting 30 students in their twenties who are enrolled in K University in Gyeongsangnam-do, and classifying them into 15 patients with mild back pain and 15 patients with normal. The subjects who participated in the experiment were measured for hip flexor and extensor muscle strength, trunk flexion and extension muscle endurance, and pelvic alignment. To measure hip joint muscle strength, biodex was used, and muscle endurance of the trunk was recorded at the end range of the trunk flexion and extension. And pelvic alignment was measured using Formetric 4D. Results: There were no significant differences in hip joint muscle strength, pelvic alignment, and trunk extension muscle endurance. The retention time was found to be significantly shorter in the mild low back pain group than in the normal group for trunk flexion muscle endurance. Conclusions: In the early stages of back pain or in the mild pain stage, training to increase muscle endurance of the flexor muscles may be helpful.

• Korean Journal of Applied Biomechanics
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• 제14권3호
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• pp.219-233
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• 2004

The purpose of this study was to compare the EMG activities of four-forearm muscles during Kumdo head striking. The four skilled and unskilled Kumdo club members were selected from D university in B city. Investigated muscles were left brachioradialis, right brachioradialis and left flexor carpi radialis, right flexor carpi radialis. Raw EMG data were collected during the head striking motions and the average EMG were calculated by the frame width of 0.05s, and then the average %MVC were calculated. The average %MVC values of each muscle in each group were compared. The results are as follows. 1) In each group, there were no significant statistical differences between every muscle over the all phases. 2) There were significant differences, however, between skilled group and unskilled group. The former got higher average %MVC at left flexor carpi radialis and the latter at right brachioradialis in the ready phase and in the impact phase.

• The Journal of Korean Physical Therapy
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• 제14권1호
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• pp.1-13
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• 2002

The purpose of this study was to investigate the effect of home exercise program on the improvement of muscle strength in the elderly. Subjects were forty members living in Daegu (20 males, 20 females), between 65 and 81 years of age. The subjects were divided into two groups; an experimental group and a control group, and each group included 10 males and 10 females. The subjects for the experimental group were participated in the home exercise program for 8 weeks, between April 2001 and June 2001. The results of this study follow: 1.General characteristics statistically significantly affecting for knee extensor strength were weight, height, right sight vision, diastolic blood pressure, pulse rate, obesity and thigh BMD; vision and thigh BMD were for knee flexor strength 2. After the exercise program, knee extensor strength in the experimental group improved 30.8% (p<0.001), and knee flexor strength improved 23.9% (p<0.001). 3. After the exercise program, there was significant difference in knee extensor strength (p<0.05) and knee flexor strength (p<0.05) between the experimental group and the control group. As a continuous health care for the elderly using this home exercise program could be helpful to enhance health of the elderly and promote their quality of life.

• Journal of the Korean Society of Physical Medicine
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• 제6권4호
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• pp.497-504
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• 2011

Purpose : Chronic cervical pain is a common source of disability in society. There has been no research regarding the amount of pressure for the deep cervical flexors during cranio-cervical flexion exercise (CCFE). The purpose of this study is to determine optimal pressure levels to facilitate deep cervical muscles (longus colli & longus capitis) during cranio-cervical flexion exercise, using ultrasound measurement of the muscles. Methods : Using a cross-sectional design, the study was performed in an experimental group of 19 subjects (7 men, 12 women) with no cervical pain. Participants were instructed to perform the CCFE, and during the five incremental stages of the test, changes in thickness, as compared to resting baseline values, were measured using ultrasonography for sternocleidomastoid muscle (SCM) and deep cervical muscles (DCF). Results : Both DCF and SCM muscles demonstrated an increase in recruitment with each progressive phase of the test. In comparing the different pressure increments, the most significant changes found in DCF thickness were between phase 2 and phase 3 (p<.05). However no differences were found between pressure increments for SCM thickness (p>.05). Conclusion : The results suggest 26 mm Hg as the optimal pressure level during cranio-cervical flexion exercise for facilitation of deep cervical flexor.

• Journal of Korean Academy of Nursing
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• 제36권2호
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• pp.341-352
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• 2006

Purpose: This study was conducted to develop & to determine the effect of an tailored falls prevention exercise for older adults. Method: Subjects consisted of 59 older adults (experimental group : 29, control group : 30) living at nursing homes. Experimental group participated in tailored falls prevention exercise for 16 weeks(3 times a week, 50 min every session). Data were collected before the exercise, 16 weeks & 24 weeks after the beginning of exercise. Results: 1) the experimental group significantly improved the muscle strength of hip extensor & flexor, knee extensor & flexor, ankle dorsiflexor, & plantar flexor compared to the control group. 2) the experimental group significantly decreased the mean time for 10 times chair stand. 3) the experimental group significantly increased the standing time on one leg and the number of heel raise for 30 seconds compared to the control group. In addition more older adults in the experimental group completed the tandem stance & semi-tandem stance for 10 seconds than the control group. 4) The experimental group significantly decreased the mean time of 6m walk and the fall frequency compared to the control group. Conclusions: This results suggest that tailored falls prevention exercise for older adults can improve muscle strength, static & dynamic balance and decrease the fall frequency of older adults.