• Journal of the Ergonomics Society of Korea
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• v.20 no.1
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• pp.63-72
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• 2001

Rearfoot control can be defined as the relative ability of a shoe to limit the amount of subtalar joint pronation immediately following footstrike. A normal amount of pronation provides a means of decreasing peak forces experienced by the leg, but excessive pronation of the foot can be arised its injures. The purpose of this study is to compare amount of pronation according to a difference between medial and later hardness of shoe midsole for better design of running shops. The experiment is examined for 7 running shoes. 8 males. to measure the Achilles tendon angle and rearfoot angle using high speed camera. The results is conducted that the changes of Achilles tendon angle significantly differ at each test shoe with increased running speed. And, a difference between medial and lateral hardness of midsole affects rearfoot motion of runner. The displacements of maximal Achilles tendon angle described a amount of pronation motion is decreased when medial hardness of midsole is large more than lateral.

• Korean Journal of Applied Biomechanics
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• v.20 no.2
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• pp.117-127
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• 2010

The axes of upper forearm coordinate system have been considered as principal axis of each segment which was component of elbow joint. The purpose of this study was to verify whether the mean direction(principal axis) of instantaneous axes of rotation for pure flexion/extension motion coincided with the flexion/extension axis of upper forearm coordinate system. The same procedure was done for pronation/supination motion. Furthermore, it was tested indirectly that there was an interaction effect between the two rotational motions. The results showed that most segment coordinate axes statistically were not consistent with the mean directions of flexion/extension and pronation/supination axes of rotation. From the results, it would be concluded that the ISB coordinate systems was proved to be a little valid for human movement analysis. There also was an effect of pronation/supination angles on flexion/extension motion.

• Journal of International Academy of Physical Therapy Research
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• v.9 no.1
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• pp.1406-1412
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• 2018

This study aimed to measure the grip strength of the dominant and non dominant hands of right-handed normal adults in the supination, pronation, and neutral positions of the forearms. The subjects of this study were instructed to make the standard posture suggested by the American Society of Hand Therapists (ASHT) in order to minimize the impact of changes in the posture of the body as follows. The grips strength was statistically different between groups (p<.05). In the follow up test using Scheffe test, the grips in the neutral position and supinator position did not show any difference, while the grip in the pronation was smaller than those of the above two other positions. The grips of the mainly used forearm and non-mainly used forearm of the study target did not show any statistically significant difference in the neutral, supinator and pronation positions of the forearm. This study is expected to provide basic information for studying the impact of the positions of the forearms on grip strength, assessing the prehensility of patients in clinical settings, and setting therapeutic goals.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.2
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• pp.108-112
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• 2024

The pronation foot can increase muscle activity, and may result in muscle fatigue and overuse syndromes. This paper aims to examine the relationships between muscle fatigue indices and pronation angles (PRA) larger than 20° for pronated foot subjects. Twelve subjects in the 15-61 age range were participated, and EMG of their biceps femoris were measured during treadmill walking at 4.5 km/h for 30 seconds. Slopes of the median frequency and the magnitude in the low frequency band were estimated respectively as muscle fatigue indices (MFIs). We hypothesized that the relationships between MFIs and PRA for the subjects in this paper be similar to those for normal ones. The test results demonstrated that we could obtain the significant correlation coefficients between MFIs and PRA (r>0.60; p<0.05).

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.19 no.2
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• pp.61-66
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• 2013

Background: This study tried to identify the bridge exercise posture for efficient exercise application by comparing muscle activity of buttocks and thighs according to internal-external rotation and pronation & supination in bridge exercise. Method: Nine males in their 20s living in D city were randomly selected as subjects. Muscles such as vastus medialis oblique (VMO), vastus lateralis (VL), semitendinosus (ST), biceps femoris (BF), gluteus maximus (GMAX), gluteus medius (GMED), tensor fasciae latae(TFL), and adductor longus (ADL) were measured using eight channel surface electromyogram (MyoSystem 1400A, Noraxon, USA) to measure muscle activity. Statistics process was performed through paired t test. Results: In the changes in electromyogram signals according to internal-external rotations according to internal-external rotation of shinbones, in most cases muscle activity was higher in external rotation than in internal rotation, but there was no statistical significance (p>.05). In particular, it was lower in TFL and ADL. There was no statistical significance in the comparison between two groups (p>.05). In the changes in electromyogram signals according to internal-external rotations according to pronation & supination of thighs, GMED showed significantly higher value in supination than in pronation (p>.05), and in ADL pronation is significantly higher than supination (p<.05). Conclusion: In internal-external rotation of shinbone and pronation & supination of thighs in bridge exercise, changes in muscle length can make effects on muscle activity of buttocks and thighs. Therefore, muscle strength enforcement program on buttocks and thighs through bridge exercise can make effects on patients with lower limb functional damages in clinical situations.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.726-729
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• 2004

This paper concerns on developing a multi-purpose test device for measuring mechanical properties of shoes. The device was modified from a commercial robot manipulator, with which impact, bending, and pronation tests were suggested to evaluate performances of shoes. From several experiments, the developed device could produce repetitive and consistent results corresponding to the different material of shoes. In the shoe industry, it is expected that the device could contribute to developing a better shoe for comfort of costumers.

• Journal of Korean Neurosurgical Society
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• v.55 no.5
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• pp.296-299
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• 2014

We report a rare case of pronator teres syndrome in a young female patient. She reported that her right hand grip had weakened and development of tingling sensation in the first-third fingers two months previous. Thenar muscle atrophy was prominent, and hypoesthesia was also examined on median nerve territory. The pronation test and Tinel sign on the proximal forearm were positive. Severe pinch grip power weakness and production of a weak "OK" sign were also noted. Routine electromyography and nerve conduction velocity showed incomplete median neuropathy above the elbow level with severe axonal loss. Surgical treatment was performed because spontaneous recovery was not seen one month later.

• Korean Journal of Applied Biomechanics
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• v.14 no.3
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• pp.83-98
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• 2004

The purpose of this study was to investigate the test-retest of plantar pressures using the F-Scan system over speeds and plantar regions. 6 healthy female subjects in 20's were recruited for the study. Plantar pressure measurements during locomotor activities can provide information concerning foot function, particularly if the timing and magnitude of the loading profile can be related to the location of specific foot structures such as the metatarsal heads. The Tekscan F-Scan system consists of a flexible, 0.18mm thick sole-shape having 1260 pressure sensors, the sensor insole was trimmed to fit the subjects' right. left shoes - sneakers shoes & dress shoes. It was calibrated by the known weight of the test subject standing on one foot. The Tekscan measurements show the insole pressure distribution as a function of the time. This finding has important implications for the development of plantar pressure test protocols where the function of the forefoot is important. According to the result of analysis it is as follows 1) Center of force trajectory in women's dress shoes display direct movement, compare with center of force trajectory in Sneaker shoes displays a little bit curved slow pronation movement. Sneaker shoes in forefoot part display very quick supination movement, therefore, this shoes effects negative effectiveness for ankle's stability Considering center of force trajectory analyzing the more center of force close straight line, the more movement can be quick movement for locomotion. For foot pressure distribution, center of force trajectory in locomotion is better to curved trajectory with pronation movement. So sneaker shoes style is good shoes considering center of pressure distribution trajectory compare with women's dress shoes. 2) Women's dress shoes increased peak pressure in medial, this is effected by high hill's height. The more increased women's dress shoes's height, the more women's peak pressure will increase, pronation can increase compare with before. Supination movement increase, this focused pressure in lateral, also, supination increased more. If the supination movement increased, foot pressure focused in lateral, therefore, it is appeared force distribution in gait direction. This is bad movement in foot's stability. 3) Women's dress shoes in landing phase displayed a long time, this is when women's dress shoes wear, gait movement is unbalance, so, landing phase displayed a long time. For compensation in gait, swing phase quick movement. 4) Women's dress shoes displayed peak pressure distribution in lateral of rearfoot part, Sneakers shoes displayed peak pressure distribution in medial of forefoot part. Its results has good impact absorption compare with women's dress shoes. In forefoot part, sneakers shoes has good propulsive force compare with women's dress shoes.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.19 no.2
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• pp.19-22
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• 2013

Background: Excessive pronation of the feet can cause excessive inner rotation of the femur, followed by increased stress in the gluteus maximum, increased front slope of the pelvis, and lumbar lordosis, which leads to lumbar pain. The aim of the present study was to use the navicular drop test to examine foot pronation that can cause lumbar lordosis and to determine whether the navicular drop is lower in patients diagnosed with lumbar disc than in patients without this diagnosis. Methods: The Navicular Drop score was set by subtracting the navicular height at a standing position from the navicular height in a sitting position. The Navicular Drop measurements for college student with and without Lumbar Herniated Intervertebral Disc were compared using an independent t-test. Results: The control group were measured right $7.44{\pm}2.96$ and left $8.04{\pm}3.23$. The experimental group were measured right $2.12{\pm}1.33$ and left $2.80{\pm}1.29$. Therefore significant difference was found between the two groups (p<0.05). Conclusions: The navicular drop affected lumbar herniated intervertebral disc.

• Korean Journal of Applied Biomechanics
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• v.16 no.1
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• pp.65-79
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• 2006

The purpose of this study was firstly to investigate correctional function of custom semi-rigid foot orthotics for excessively pronated people during gait by observing comfort, navicular movement and leg muscles' activity according to short-term and mid-term wearing duration and secondly to understand positive and/or negative point of view of a recently proposed paradigm related to foot orthotics more profoundly. Sixteen subjects who showed excessive pronation at navicular drop test were recruited for this study. Custom semi-rigid foot orthotics were made fitting for foot characteristics of the subjects by podiatry division of Otto Bock Korea company. While wearing the foot orthotics for two months, comfort of wearing were questioned and vertical navicular movement and electromyography of leg muscles during gait were measured at the condition of both immediately after and 2 months after including a control condition, respectively. The subjects were required to walk on a treadmill at the speed of 1.5m/s and four digital video camera filmed the movement of navicular process at the speed of 60 frames/s. In conclusion, in excessively pronated group continuous increase of comfort from short-term to mid-term wearing of custom foot orthotics is assumed to be closely related with short-term and mid term correctional action, of which are consisted the decrease of the range of navicular drop and navicular raisins- the faster timing of minimum navicular position occurring, and the decrease of leg muscles' activities. This conclusion could lead to positively accept new paradigm related to foot orthotics suggested by Nigg and the author suggest that in the future study the variable which could observe navicular movement would be one of major variables to study preferred path of skeleton in the paradigm.