• Korean Journal of Applied Biomechanics
• /
• v.15 no.2
• /
• pp.185-196
• /
• 2005

Recently among several tennis techniques forehand stroke has been greatly changed in the aspect of spin, grip and stance. The most fundamental factor among the three factors is the stance which consists of open, square and closed stance and it is very important to know the patterns of plantar pressure distribution for the better understanding of forehand stroke. Therefore, the purpose of this study was to investigate the change of plantar pressure distribution according to close, square and open stance patterns during forehand stroke in tennis. Three high school tennis players were recruited for the study and required to perform forehand stroke five consecutive trials in the condition of open, square and close stance. The forehand strokes were filmed with two digital video cameras and measured with pedar system for plantar pressure. The plantar regions under the foot were divided into 3 regions, which were forefoot, midfoot, and rear foot.. In conclusion, the first hypothesis, "The plantar pressure of close stance during forehand stroke would be distributed more largely to the left foot.", was rejected and the result showed that The plantar pressure of close stance during forehand stroke was distributed transferring from right foot to left foot similar to square stance. The second hypothesis, "The plantar pressure of square stance during forehand stroke would be distributed transferring from right foot to left foot." was accepted. The third hypothesis, "The plantar pressure of open stance during forehand stroke would be distributed more largely to the right foot.", was accepted.

• The Journal of Korean Physical Therapy
• /
• v.22 no.3
• /
• pp.49-53
• /
• 2010

Purpose: The purpose of this study was to investigate the plantar pressure distribution between the affected and unaffected side in adult hemiplegia during gait with the use of a quad-cane. Methods: Thirty-four stroke patients from 34 to 83 years of age were enrolled in this study, and in random order, all patients were asked to walk at their most comfortable speed three times along a walkway with the use of quad-cane over a period of three days. Plantar pressure distribution was measured with regard to foot contact pattern and center of pressure (CoP) trajectories during the stance phase, progressing from heel-strike to toe-off. The F-scan system was used to compare the foot pressure of the affected and unaffected sides. Results: A significant reduction in the total contact area, the width of fore foot (FF) and hind foot (HF), and anterior/posterior (AP) CoP trajectory of the affected side was found. However, contact pressure of the hind foot on the affected side during walking increased when compared to that on the unaffected side. Conclusion: We demonstrated that plantar pressure distribution on the affected side of adult hemiplegia patients was generally poorer than that on the unaffected side when these patients walked with cane assistance. However, the use of a quad-cane was shown to increase contact pressure of the hind foot on the affected side because weight can be borne on the affected side during heel-strike with use of the cane.

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

• Physical Therapy Korea
• /
• v.20 no.4
• /
• pp.55-64
• /
• 2013

The first purpose was to identify the plantar pressure distributions (peak pressure, pressure integral time, and contact area) during level walking, and stair ascent and descent in asymptomatic flexible flatfoot (AFF). The second purpose was to investigate whether peak pressure data during level walking could be used to predict peak pressure during stair walking by identifying correlations between the peak pressures of level walking and stair walking. Twenty young adult subjects (8 males and 12 females, age $21.0{\pm}1.7$ years) with AFF were recruited. A distance greater than 10 mm in a navicular drop test was defined as flexible flatfoot. Each subject performed at least 10 steps during level walking, and stair ascent and descent. The plantar pressure distribution was measured in nine foot regions using a pressure measurement system. A two-way repeated analysis of variance was conducted to examine the differences in the three dependent variables with two within-subject factors (activity type and foot region). Linear regression analysis was conducted to predict peak pressure during stair walking using the peak pressure in the metatarsal regions during level walking. Significant interaction effects were observed between activity type and foot region for peak pressure (F=9.508, p<.001), pressure time integral (F=5.912, p=.003), and contact area (F=15.510, p<.001). The regression equations predicting peak pressure during stair walking accounted for variance in the range of 25.7% and 65.8%. The findings indicate that plantar pressures in AFF were influenced by both activity type and foot region. Furthermore the findings suggest that peak pressure data during level walking could be used to predict the peak pressure data during stair walking. These data collected for AFF can be useful for evaluating gait patterns and for predicting pressure data of flexible flatfoot subjects who have difficulty performing activities such as stair walking. Further studies should investigate plantar pressure distribution during various functional activities in symptomatic flexible flatfoot, and consider other predictors for regression analysis.

• Journal of Fashion Business
• /
• v.28 no.1
• /
• pp.83-97
• /
• 2024

A plantar pressure mat with visual notifications was developed to confirm whether individuals can effectively balance themselves and correct imbalances. The sensor-embedded mat was made with a commercial yoga mat, and was tested on seven working women in their 30s to determine plantar pressure distribution when standing and squatting, and if they could recognize and correct imbalances with visual feedback. The study found that visual notifications significantly changed the plantar pressure ratio of the forefoot and hindfoot, as well as the left and right foot plantar pressure ratio. Without notifications, the center of gravity was more concentrated in the rear foot than the forefoot in both standing and squatting positions. Visual notifications showed that the center of gravity, which was largely focused on the rear foot, was distributed to the forefoot, resulting in a more evenly distributed center of gravity throughout the sole. For the change in left and right plantar pressure, the weight that was largely loaded on the left side was distributed to the right foot through the visual notification mat, confirming a more balanced plantar pressure.

• Korean Journal of Applied Biomechanics
• /
• v.22 no.1
• /
• pp.113-121
• /
• 2012

The purpose of this study was to evaluate the effects of forefoot rocker shoes equipped with a metatarsal bar on lower extremity muscle activity and plantar pressure distribution. Ten healthy women in the age of twenties were participated in this study as the subjects. All subjects walked on a treadmill(Gait Trainer, BIODEX, USA) wearing normal shoes and metatarsal bar shoes, during which the plantar pressure distribution and muscle activity were measured. Using Pedar-X system(Novel Gmbh, Germany), the plantar pressure was measured for six regions of the foot: forefoot, midfoot, rearfoot, 1st metatarsal, 2-3th metatarsal, and 4-5th metatarsal, and for each sub-region, 4 features such as maximum force, contact area, peak pressure, and mean pressure were analyzed based on the plantar pressure. EMG(Electromyography) activity was measured by attaching surface electrodes to the rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius medial head, and magnitude of muscle contraction was analyzed in IEMG(Integrated EMG) value. The results show that the maximum force, contact area, peak pressure, and mean pressure in the midfoot all increased while maximum force, peak pressure, contact area, mean pressure in the 1st metatarsal and 2-3th metatarsal all decreased when wearing functional shoes. Also, muscle activities in the four muscles were all decreased when wearing the functional shoes. This paper suggests that forfoot rocker shoes equipped with a metatarsal bar can help disperse the high pressure and absorb the shock to the foot as well as give positive influence on gait pattern and postural stability by reducing muscle fatigue during walking.

• Proceedings of the KOSOMBE Conference
• /
• v.1997 no.05
• /
• pp.241-244
• /
• 1997

23 hallux valgus patients were evaluated with clinical examinations and plantar pressure distribution measurements. A masking method for detailed plantar pressure distribution analyses was suggested. With higher grade of hallux valgus, pressure, contact length & area, and impulse on metartasus were significantly increased. Localized pressure concentration is very important in foot diseases and appropriate plantar pressure distributions should be considered on any shoe design.

• Journal of Korean Physical Therapy Science
• /
• v.22 no.2
• /
• pp.43-47
• /
• 2015

Background : Many factors affect foot and ankle biomechanics during walking, including gait speed and anthropometric characteristics. This study examined the effect of walking speed on peak plantar pressure during the walking. Method : Thirty two normal healthy subjects (16 men, 16 women) were recruited. Peak plantar pressure was investigated using pressure distribution platforms (Pedoscan system) under the hallux heads of the first, second, and third metatarsal bones, and heel. Result : The results also suggest that slow walking speeds may decrease forefoot peak plantar pressure in patients with peripheral neuropathy who have a high risk of skin breakdown under the forefoot(p<0.05). Conclusion : The results also suggest that slow walking speeds may decrease forefoot peak plantar pressure in patients with restricted low extremity range of motion who have a high risk of skin breakdown under the forefoot.

• Journal of the Korean Society of Physical Medicine
• /
• v.16 no.3
• /
• pp.115-121
• /
• 2021

PURPOSE: This study analyzed the correlation between the plantar pressure and body alignment according to the dominant hand of elementary school baseball players. METHODS: The subjects consisted of 32 elementary school baseball players. The 32 players were classified in the right-hand dominant group (Rt. Group, n = 22) and left-hand dominant group (Lt. group, n = 10). The plantar pressure was measured using a pedoscan to determine the maximum pressure and pressure distribution. The body alignment was measured using a fometric 4D to measure the trunk imbalance angle (TI), pelvic tilt angle (PTi), pelvic torsion angle (PTo), pelvis rotation angle (PR), kyphotic angle (Ky), lordotic angle (Lo), and trunk torsion angle (TT). RESULTS: Participants showed correlations in the Rt. group, according to the left maximum pressure, Lo (r = .592, p < .05), and TT (r = .514, p < .05); according to the right maximum pressure, PR (r = .539, p < .05), and Lo (r = .503, p < .05). In the left pressure distribution, the PR (r = -.521, p < .05) showed a negative correlation. In the Lt. group, the PT (r = -.591, p < .05) showed a negative correlation in the left pressure distribution. CONCLUSION: These results can be used as basic data for a body analysis study of elementary school baseball players in the future.

• Annals of Rehabilitation Medicine
• /
• v.39 no.6
• /
• pp.897-904
• /
• 2015

Objective To investigate differences in plantar pressure distribution between a normal gait and unpredictable slip events to predict the initiation of the slipping process. Methods Eleven male participants were enrolled. Subjects walked onto a wooden tile, and two layers of oily vinyl sheet were placed on the expected spot of the 4th step to induce a slip. An insole pressure-measuring system was used to monitor plantar pressure distribution. This system measured plantar pressure in four regions (the toes, metatarsal head, arch, and heel) for three events: the step during normal gait; the recovered step, when the subject recovered from a slip; and the uncorrected, harmful slipped step. Four variables were analyzed: peak pressure (PP), contact time (CT), the pressure-time integral (PTI), and the instant of peak pressure (IPP). Results The plantar pressure pattern in the heel was unique, as compared with other parts of the sole. In the heel, PP, CT, and PTI values were high in slipped and recovered steps compared with normal steps. The IPP differed markedly among the three steps. The IPPs in the heel for the three events were, in descending order (from latest to earliest), slipped, recovered, and normal steps, whereas in the other regions the order was normal, recovered, and slipped steps. Finally, the metatarsal head-to-heel IPP ratios for the normal, recovered, and slipped steps were $6.1{\pm}2.9$, $3.1{\pm}3.0$, and $2.2{\pm}2.5$, respectively. Conclusion A distinctive plantar pressure pattern in the heel might be useful for early detection of a slip event to prevent slip-related injuries.