• Journal of Biomedical Engineering Research
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• v.34 no.2
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• pp.80-90
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• 2013

Recently, functional insoles of wedge-type it is for the young to raise their height inserted between insole and heel cause foot pain and disease. Additionally, these have a problem with stability and excessively load-bearing during gait like high-heel shoes. In this study, we compared the changes in biomechanical characteristics of foot with different insole thickness then we will utilize for the development of the insole with the purpose of relieving the pain and disease. Subjects(male, n = 6) measured COP(center of pressure) and PCP(peak contact pressure) on the treadmill(140cm/s) using F-scan system and different insole thickness(0~50 mm) between sole and plantar surface during gait. Also, we computed changes of stresses at the foot using finite element model with various insole thickness during toe-off phase. COP moved anterior and medial direction and, PCP was increased at medial forefoot surface, $1^{st}$ and $2^{nd}$ metatarsophalangeal, ($9%{\uparrow}$) with thicker insoles and it was show sensitive increment as the insole thickness was increased from 40 mm to 50 mm. Change of the stress at the soft-tissue of plantar surface, $1^{st}$ metatarsal head represents rapid growth($36%{\uparrow}$). Also, lateral moments were increased over the 100% near the $1^{st}$ metatarsal as the insole thickness was increased from 0 mm to 30 mm. And it is show sensitive increment as the insole thickness changed 10 mm to 20 mm. As a result, it was expected that use of excessively thick insoles might cause unwanted foot pain at the forefoot region. Therefore, insole thickness under 30 mm was selected.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.14 no.1
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• pp.39-47
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• 2008

Purpose : The purpose of this study was to investigate the change of the peak plantar pressure distribution under the foot areas and the range of motion (ROM) of ankle joint according to gradients in treadmill gait. Method : Thirty normal subjects (15 male and 15 female) walked on treadmill at three gradient conditions ($0^{\circ}$, $10^{\circ}$, and $15^{\circ}$) in normal speed. The ankle ROM was measured using the CMS70P that is three dimensional analyzer for excursion of ankle ROM, plantar flexion, and dorsi flexion. The peak plantar pressure distribution under the hallux, 1st metatarsal head (MTH) and heel was measured using the F -Scan system with an in-shoe sensor. Data was collected from 9 steps of left sife foot in at each gradient condition while all subjects walked. Result : As the treadmill gradient increased, the excursion of ankle joint was significantly increased (p<.05). Also, plantar flexion and dorsi flexion was significantly increased according to treadmill gradients (p<.05). The peak plantar pressure under the 1st MTH was significantly increased (p<.05) and the peak plantar pressure under the heel was significantly decreased (p<.05) as the treadmill gradient increased. No significant different in the peak plantar pressure under the hallux was observed. Conclusion : This study suggests that physical therapy for patients who have limited ankle ROM should be considered sufficient range of motion for functional ambulation. And individuals that have painful forefoot syndromes, including metatarsalgia, hallux valgus, and plantar ulceration should be careful in walking to uphill, as there is high plantar pressure under the forefoot.

• Korean Journal of Applied Biomechanics
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• v.16 no.1
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• pp.19-30
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• 2006

The purpose of this study was to examine the effect of foot orthotics on the overall comfort and muscle activity during running. The subjects were 10 members from the joggers' club which consisted of 2 women and 8 men. These individuals ran on the treadmill by 4.0m/s speed with and without the custom foot orthotics. The data concerning the overall comfort was collected by a questionairre that examined the overall comfort, heel cushioning, forefoot cushioning, medio-lateral control, arch height, heel cup fit, shoe heel width, forefoot width, and shoe length The MegaWin ver. 2.1(Mega Electronics lid, Ma. Finland) was used to gain electromyography signals of the muscle activity; Tibialis anterior, medial gastronemius, lateral gastronemius, vastus lateralis, vastus medialis, biceps femoris, and rectus femoris were measured. The results of the study were as follows. 1. During running the overall comfort was higher for the foot arthotic condition than the nonorthotic condition. Among the inquiries the overall comfort showed the biggest difference comparing the two conditions. and the shoe heel width showed the highest score for contort. 2 The muscle activity of the biceps femoris, and vastus lateralis in the stance period decreased. due to the foot orthotics. The muscle activity of the vastus medialis in the swing period also decreased and the muscle activity tibialis anterior in the stance and swing stance decreased as well During running, orthotics showed positive result in foot comfort. The foot comfort related to decreased stress, muscle activity, and foot arch strain. Overall comfort and the adequate decrease of muscle activity were associated with injury prevention and the best method to prevent injury semms to be the maintenance of foot comfort.

• Korean Journal of Applied Biomechanics
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• v.28 no.1
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• pp.45-54
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• 2018

Objective: The purpose of this study was to investigate the effect of foot strengthening exercise program and functional insoles on joint angle and plantar pressure in elderly women. Thirteen elderly women who were enrolled in a university senior citizens academy of a metropolitan city in 2017 were divided into two groups: exercise group with functional insole (n=7) and exercise group without functional insole (n=6). Method: Three-dimensional motion analysis and Pedar-X were performed to compute the joint angle and the foot plantar pressure, respectively. Two-way repeated measure ANOVA was conducted to compare dependent variables within and between groups. The significance level was set at ${\alpha}=.05$. Results: The range of motion (ROM) of the ankle, knee, and hip joints in the exercise group with functional insole increased significantly more than the exercise group without functional insole. In both the experimental group and the comparison group, the maximum foot plantar pressure and the mean foot plantar pressure were decreased, but the comparison group without functional insole showed more decrease. Since the experimental group demonstrated greater pressure than the comparison group in the contact area (forefoot, midfoot), it was distributed over a greater area. Conclusion: The results of this study suggest that participation in foot strengthening exercises and using a functional insole has more positive effects than foot strengthening exercises alone on the joint angle and plantar pressure in elderly women. Increased foot plantar pressure led to an increased contact area (forefoot, midfoot) for distribution of the foot plantar pressure, but the effect of reducing the maximum and average plantar pressures was incomplete. However, wearing functional insoles along with exercise, could help in improving the stability of the joints, by increasing the range of motion, and could help the elderly in movement of the muscles more effectively, leading to an improvement in gait function.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.81-94
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• 2007

The purpose of this study was to critically review biomechanical studies on foot orthoses (FO) in normal and diseased foot and provide beneficial information obtained from researches until now and future researching focus. The search was performed by Medline and Embase database including studies published in English from January 1980 to April 2007. The searching terms were foot orthoses, foot orthotics, insoles and shoe insert. 57 studies including 54 journal articles and 3 abstracts were finally selected under the conditions of having clinical trials, FO, control condition, movement, scientific measuring system. The reviewed studies were divided into 10 categories according to subject characteristics; healthy normal, excessive pronation or flexible flat foot, rheumatoid arthritis, diabetes, medial knee osteoarthritis, forefoot varus, plantar fasciitis, patellofemoral syndrome, cavus foot and finite element model. In summary, first, soft and semirigid FOs with some degree of cushioning showed much higher comfort and efficacy than rigid FO. Second, no big differences between prefabricated and custom FO were shown. Third, the full length's FO was preferable to the half length's FO or simple arch supports. Fourth, the wearing of FO combining medial arch supports and metatarsal dome made positive roles to enhance comfort and functionality and redistribute plantar pressure under the foot. Fifth, for patients with knee-related diseases lateral wedges were preferable. Sixth, measuring systems were properly applied according to the types of foot diseases.

• Korean Journal of Applied Biomechanics
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• v.29 no.3
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• pp.173-183
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• 2019

Objective: The aim of this study was to investigate the correlation coefficients between anthropometric parameters of the foot and kinetic variables during running. Method: This study was conducted on 21 healthy young adults (age: $24.8{\pm}2.1yes$, height: $177.2{\pm}5.8cm$, body mass: $73.3{\pm}7.3kg$, foot length: $256.5{\pm}12.3mm$) with normal foot type and heel strike running. To measure the anthropometric parameters, radiographs were taken on the frontal and sagittal planes, and determined the length and width of each segment and the navicular height. Barefoot running was performed at a preferred velocity ($3.0{\pm}0.2m/s$) and a fixed velocity (4.0 m/s) on treadmill (Bertec, USA) in order to measure the kinetic variables. The vertical impact peak force, the vertical active peak force, the braking peak force, the propulsion peak force, the vertical force at mid-stance (vertical ground reaction when the foot is fully landed in mid-stance or at the point where the weight was uniformly distributed on the foot) and the impact loading rate were calculated. Pearson's correlation coefficient was used to investigate the relationship between anthropometric variables and kinetical variables. The significance level was set to ${\alpha}=.05$. Results: At the preferred velocity running, the runner with longer forefoot had lower active force (r=-.448, p=.041) than the runner with short forefoot. At the fixed velocity, as the navicular height increases, the vertical force at full landing moment increases (r= .671, p= .001) and as the rearfoot length increases, the impact loading rate decreases (r=- .469, p= .032). Conclusion: There was a statistically significant difference in the length of fore-foot and rearfoot, and navicular height. Therefore it was conclude that anthropometric properties need to be considered in the foot study. It was expected that the relationship between anthropometric parameters and kinetical variables of foot during running can be used as scientific criteria and data in various fields including performance, injury and equipment development.

• PNF and Movement
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• v.19 no.2
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• pp.233-242
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• 2021

Purpose: The purpose of this study was to determine the changes in foot contact area and pressure when walking with a functional insole that emphasizes the Hallux point as compared to a general insole. Methods: In this study, an experiment was conducted to investigate changes in plantar pressure and contact area for a functional insole that emphasized the Hallux point as compared to a general insole. A lower extremity robot was used for walking reproduction. First, the gait sequence according to the two insoles was determined through a randomized controlled trial comparison. According to the sequence procedure, the insole was attached to the shoe and then worn on the right side of the lower extremity robot for gait reproduction at a normal gait speed of 20 steps per minute. After programming the robot to walk, the experiment was carried out. The result value was determined by averaging the pressure and area data of the fore and rear foot measures after walking at 20 steps per minute. Results: The functional insole that emphasized the hallux point significantly increased the forefoot and rearfoot contact area (p < 0.05) and significantly decreased the forefoot and rearfoot contact pressure (p < 0.05) compared to the general insole. Conclusion: A functional insole that emphasizes the hallux point does not collapse the medial longitudinal arch during gait, increasing foot stability and reducing fatigue. Thus, this functional insole needs to be widely used clinically.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.91-97
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• 2021

Background In postaxial polysyndactyly of the foot, the choice of which toe to excise is controversial. It is often treated by resection of the fifth toe to save the lateral neurovascular bundles of the sixth toe. However, the sixth toe is often short and laterally deviated, which may require wedge osteotomy, potentially shortening the phalanx and compromising circulation. This study outlines an individualized method to spare the length and axis of the fifth toe in polysyndactyly with a short and deviated sixth toe. Methods We retrospectively analyzed 38 patients who underwent surgery between 2006 and 2019. The fifth toe was spared in 18 cases, and the sixth toe in 20 cases. The ratios of the forefoot width, angle difference, and toe length were compared between the affected and unaffected sides postoperatively. Complications and subjective judgments on cosmetic results were recorded and compared. Results No significant between-group differences were observed for sex, age at surgery, or the follow-up period. The forefoot width ratio did not significantly differ between the groups. However, the angle difference and toe length ratios showed significantly better results in the fifth toe-spared group than in the sixth toe-spared group (P<0.05 and P<0.01, respectively). There were no cases of impaired circulation, and subjective evaluations revealed satisfactory results in the fifth toe-spared group. Conclusions In cases with short and deviated sixth toes, sparing the fifth toe is an effective method of cosmetic treatment. The surgical results were satisfactory, with an improved appearance and no residual deformities.

• PNF and Movement
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• v.20 no.3
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• pp.431-441
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• 2022

Purpose: The purpose of this study was to compare the changes in the contact area, maximum pressure, maximum mean pressure, and maximum force of functional insoles and general insoles when walking. Methods: Foot pressure was measured by the ignition of functional insoles and general insoles on Company N shoes. The foot pressure was measured using a precision pressure distribution meter (Pedar - X mobile system, Novel, Germany). Each insole sensor contained 99 independent cells and was inserted between the foot and the shoe. A wireless Bluetooth-type program was used to measure the pressure detected by the measuring insoles. In order to eliminate adaptation and fatigue caused by wearing the guide during the experiment, sufficient rest was taken between each experiment, and the wearing order was randomly selected. Results: Functional insole significantly increased the forefoot and midfoot (medial, lateral) (p<0.05), while total foot, forefoot, and rearfoot peak pressure significantly decreased (p < 0.05) compared to the general insole. Conclusion: In the functional insole, a high contact area was measured inside, even in the middle of the foot, leading to a proper change in foot pressure. It was confirmed that the contact area was reduced and dispersion occurred well. In addition, it was found that the maximum pressure in the front and back of the entire foot was reduced, so the weight pressure dispersion in the functional insole was evenly distributed, and the maximum average pressure change was similar.

• The Journal of the Society of Stroke on Korean Medicine
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• v.14 no.1
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• pp.61-70
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• 2013

■ Objectives The goal of this pilot study is to observe the change of gait pattern in a patient after peroneal nerve electrical stimulation(PNST). ■ Methods We analyzed the gait pattern of stroke patient using treadmill gait analysis system before and after PNST for seven weeks. The PNST was carried out for 20minutes every day except Sunday. In addition, the measurement was carried out every Saturday. At the fifth week, the PNST was not carried out to confirm whether the effect of PNST was disappeared immediately when PNST was not applied. ■ Results After PNST, while heel contact time and heel max force increased and forefoot and midfoot max force decreased, the gait parameters such as cadence, velocity, swing phase, stance phase, total double support, step length, stride length, step time, stride time and forefoot contact time, were not changed. ■ Conclusion Gait of a patient with cerebral stroke was changed positively after PNST.