Thermoregulation in Two Models of Trail Run Socks with Different Fabric Separation.

BACKGROUND: Trail running socks with the same fibers and design but with different separations of their three-dimensional waves could have different thermoregulatory effects. Therefore, the objective of this study was to evaluate the temperatures reflected on the sole of the foot after a mountain race with the use of two models of socks with different wave separations. MATERIAL AND METHODS: In a sample of 34 subjects (twenty-seven men and seven women), the plantar temperature was analyzed with the thermal imaging camera Flir E60bx® (Flir systems, Wilsonville, OR, USA) before and after running 14 km in mountainous terrain at a hot temperature of 27 °C. Each group of 17 runners ran with a different model of separation between the waves of the tissue (2 mm versus 1 mm). After conducting the post-exercise thermographic analysis, a Likert-type survey was conducted to evaluate the physiological characteristics of both types of socks. RESULTS: There was a significant increase in temperature in all areas of interest (p < 0.001) after a 14 km running distance with the two models of socks. The hallux zone increased in temperature the most after the race, with temperatures of 8.19 ± 3.1 °C and 7.46 ± 2.1 °C for the AWC 2.2 and AWC 3, respectively. However, no significant differences in temperature increases were found in any of the areas analyzed between the two groups. Runners perceived significant differences in thermal sensation between AWC 2.2 socks with 4.41 ± 0.62 points and AWC 3 with 3.76 ± 1.03 points (p = 0.034). CONCLUSION: Both models had a similar thermoregulatory effect on the soles of the feet, so they can be used interchangeably in short-distance mountain races. The perceived sensation of increased thermal comfort does not correspond to the temperature data.

Thermal Differences in the Plantar Surface Skin of the Foot after Using Three Different Lining Materials for Plantar Orthotics.

The lining materials of plantar orthoses are chosen for their hardness, breathability, and moisture absorption, but without there being any clear scientific criterion. Thermographic analysis would provide information about the thermal response of the sole of the foot, and would thereby allow the choice to be adapted in accordance with this criterion. The objective of this study was to evaluate plantar temperatures after the use of three materials with different characteristics. Plantar temperatures were analyzed by using a FLIR E60BX thermographic camera on 36 participants (15 men and 21 women, 24.6 ± 8.2 years old, 67.1 ± 13.6 kg, and 1.7 ± 0.09 m). Measurements were made before and after (3 h) the use of three lining materials for plantar orthoses (Material 1: PE copolymer; Material 2: EVA; Material 3: PE-EVA copolymer) on different days. For Material 1 (PE), the temperature under the heel was significantly higher after exercise, increasing from 30.8 ± 2.9 °C to 31.9 ± 2.8 °C (p = 0.008), and negative correlations were found between room temperature and the pre/post temperature difference for the big toe (r = -0.342, p = 0.041) and the 1st metatarsal head (r = -0.334, p = 0.046). No significant pre/post temperature differences were found with the other materials. The three materials thermoregulated the plantar surface efficiently by maintaining the skin temperature at levels similar to those evaluated before exercise. If PE is used as a lining material, it should be avoided for the heel area in patients with hyperhidrosis or those with a tendency to suffer from skin pathologies due to excess moisture.

Age related changes in the Q angle of non-professional football players.

Background: Football practice involves a great muscular demand, leading to the development of the lower limbs that, on occasions, can cause deviations from the normal anthropometric values. The quadriceps angle (Q angle) is a value often taken as a reference for the alignment of the lower limbs. Objective: To observe the changes of the Q angle in young football players, because of muscular effort, analyzing the differences between four groups of different ages and to determine whether the playing position might influence these variations. Methods: A cross sectional study was carried out with 104 male subjects divided into four groups according to age: under 8 years-old, 8-17 years-old, 17-21 years-old and over 21 years-old. A photograph was taken in standing position and the Q angle was plotted with KINOVEA® software. As for the reliability of the measurements, intraclass intra and interobserver coefficient were 0.958 and 0.860 respectively. The study was conducted in mid-season. Results: Q angle value is greater in those under 8 years of age and decreases gradually and significantly (p < 0.005) until 17-21 years of age, where it stabilizes at values of 5.73° ± 2.78 for right Q angle and 5.88° ± 2.55 for left Q angle. Two way ANOVA demonstrated a significant group*position interaction for goalkeepers with a medium effect size in both angles (p < 0.001) with a medium effect (η2 Right Q angle = 0.31; η2 Left Q angle = 0.37). The values remain unchanged in subjects over 21 years of age (p > 0.005), except for goalkeepers, who suffered a difference in the evolution of the angle within their age category (p < 0.005) and with a high effect size with the other positions (value > 0.8) except forward (value < 0.5). Conclusion: This study determines that the Q angle in football players decreases with growth, reaching values below 15° at the end of development. Playing positions only influence players over the age of 21, and the Q-angle of goalkeepers is greater than that of other players.

The Podoprint® plantar pressure platform: Evaluation of reliability and repeatability, and determination of the normality parameters.

INTRODUCTION: The Podoprint® pressure platform system is widely used in routine podiatric clinical practice to measure plantar pressures. It allows non-invasive examination of the patient, and provides fast results with high levels of precision, reliability, and repeatability. Once these conditions have been demonstrated, the clinical and/or research use of baropodometry allows results to be obtained in the field of podology that are far from inconsiderable. The study was designed to evaluate the repeatability and reliability of the platform, and to identify the normal foot pressure parameters. METHODS: Records were collected from 52 random healthy individuals, 10 men and 42 women, in two sessions separated by one week. The study variables were: maximum pressure, mean pressure, support surface areas (heel, midfoot, and forefoot), and contact time. Repeatability and reliability were evaluated by calculating the interclass correlation coefficient (ICC) and the coefficient of variation (CV) in the three tests. RESULTS: The ICCs showed moderate to good repeatability for the variables of interest, and the CVs were all less than 18%. The maximum pressure was under the forefoot (mean 2675.4 ± 513.8 g/cm2). The mean contact time of the steps was 0.72 ± 0.07 s. CONCLUSIONS: The Podoprint® system is a reliable tool for evaluating the distribution of plantar pressures in the dynamic study of the barefoot gait of healthy individuals.

Socks with an U-shaped 3D discharge element are capable to reduce dynamic plantar pressures under the central forefoot.

Cushioning for the central and plantar zone of the forefoot, integrated into the body of the sock, could reduce excess pressures in that zone. The objective of this study was to verify the capacity of a sock with a cushioning element to reduce forefoot plantar pressures relative to the same sock model without that element. Dynamic plantar pressures were measured in a sample of 38 participants (25 women and 13 men) using the FootScan plate system following the two-step protocol. Measurements were made in three situations selected at random - barefoot, wearing control socks, and wearing the experimental cushioned socks. Maximum pressures were analysed in seven zones of the forefoot (hallux, lesser toes, and 1st to 5th metatarsal heads). The zone of greatest plantar pressure was in all situations located under the 3rd metatarsal head. The pressure was lower (p = 0.009) under the 2nd metatarsal head with the experimental sock (10.2 ± 3.1 N/cm2) than with the other two conditions - barefoot (11.8 ± 3.7 N/cm2) and control sock (11.9 ± 4.9 N/cm2). The 3rd metatarsal head presented lower plantar pressures (p = 0.004) with the experimental sock (12.6 ± 3.8 N/cm2) than barefoot (14.5 ± 4.9 N/cm2). The experimental socks, with plantar cushioning, were able to effectively reduce the plantar pressures on the central part of the forefoot. This reduction may lead to less discomfort for subjects suffering pain in this area, It may also result in avoiding the appearance of possible skin lesions associated with excess pressure (such as calluses, corns, or blisters).

An Assessment of Balance through Posturography in Healthy about Women: An Observational Study.

The incidence of falls in adults constitutes a public health problem, and the alteration in balance is the most important factor. It is necessary to evaluate this through objective tools in order to quantify alterations and prevent falls. This study aims to determine the existence of alteration of balance and the influence of age in a population of healthy women. Static posturography was performed on 49 healthy adult women with no history of falls in four different situations using the Romberg test with the NedSVE/IBV® platform. The variables studied were the body sway area and the anteroposterior and mediolateral displacements. The situation of maximum instability occurred in RGC (p = 0.001), with a significant increase in anteroposterior oscillations regarding the ML (p < 0.001), with no correlation to age. Age alone does not influence the balance in the sample studied, other factors must come together to alter it. The joint cancellation of visual and somatosensory afferents could facilitate the appearance of falls, given that it is a situation of maximum instability. Proprioceptive training is interesting as a preventive strategy for falls.

Effectiveness of a Central Discharge Element Sock for Plantar Temperature Reduction and Improving Comfort.

U-shaped plantar cushions could help reduce stress affecting the central forefoot without the need for an orthosis, but they are yet to be integrated as an element in socks. The objective of this study was to verify the effectiveness of a sock with a central discharge element in terms of plantar temperature and comfort. The sample comprised 38 subjects (13 men and 25 women). Their plantar temperatures were measured with a thermographic camera in a basal situation and after each of two 10-minute walks around an indoor circuit during which they wore either control or experimental socks at random (the same design, weight, and fiber, but with the plantar cushioning element added). After the walks, each subject responded to a comfort questionnaire (five-point Likert scale), blindly scoring the two socks. The highest temperatures (28.3 ± 2.7 °C) were recorded in the zone of the second and third metatarsal heads. With the experimental socks, the observed temperature increase in the central forefoot zone was significantly less than with the control socks (31.6 vs. 30.6 °C, p = 0.001). The subjects found the experimental socks to be more comfortable than the controls (4.63 ± 0.5 vs. 4.03 ± 0.5, p < 0.001). The discharge element included in the experimental socks was effective since it reduced the contact zones and excess friction with the ground, thereby lessening overheating by more than 1 °C. Furthermore, the experimental socks were perceived as being more comfortable by the subjects who had mild and occasional foot discomfort.

Influence of creams with different urea concentrations on plantar skin hydration.

INTRODUCTION: The skin is the body's outermost organ, and one of its main functions is to provide protection against potential infections. Hydration is related to the proper functioning of the skin, hindering the appearance of wounds or cracks which could lead to the occurrence of infections or other dermatological alterations. The skin of the foot is thicker than that of the rest of the body due to the load it supports, and it is more complicated to maintain. The intention of this study was to evaluate the efficacy of different concentrations of urea (5% and 20%) in hydrating the foot compared to a placebo cream. METHODS: The study was carried out with 60 subjects of ages from 20 to 35 years in age. The experimental protocol was initiated by creating three randomized groups (1:1:1), each being treated with a different cream: placebo, 5% urea cream, and 20% urea cream. The examination was carried out using a non-invasive instrument (Corneometer CM 825®) that detects the skin surface hydration. RESULTS: Analysis of the hydration of the different study zones according to the cream used showed no significant differences between the placebo and 5% urea for the first MTH and heel, but a significant difference for the fifth MTH. There were significant differences in all study areas between the placebo and 20% urea creams, but none between the 5% urea and 20% DISCUSSION/CONCLUSION: The conclusion drawn was that skin hydration was greater with the 20% urea cream versus the placebo, but there were no differences found when comparing either the 20% and 5% urea creams or the placebo and 5% urea creams.

Modification of Pronated Foot Posture after a Program of Therapeutic Exercises.

Working on the intrinsic musculature of the foot has been shown to be effective in controlling pronation. However, the potential coadjuvant effect that involving other muscle groups might have on foot posture remains unknown. The aim was, therefore, to assess whether a 9-week intrinsic and extrinsic foot and core muscle strength program influenced foot posture in pronated subjects. The participants were 36 healthy adults with pronated feet that were randomly assigned to two groups. The experimental group (n = 18) performed a strengthening exercise protocol for 9 weeks (two sessions of 40 min per week), while the control group (n = 18) did not do these exercises. After 9 weeks, the foot posture index (FPI) scores of the two groups were analyzed to detect possible changes. The FPI at the baseline was 8.0 ± 1.5. After the 9 weeks, the experimental group showed significantly reduced FPI from 8.1 ± 1.7 to 6.4 ± 2.1 (p = 0.001), while the control group had the same score as pre-intervention (FPI 8 ± 1.2, p = 1.0). The FPI scores showed no significant differences by sex. Strengthening of the intrinsic and extrinsic foot and core muscles contributed to improving foot posture in adults, reducing their FPI by 1.66 points.

Longitudinal Analysis of Plantar Pressures with Wear of a Running Shoe.

Running shoes typically have a lifespan of 300-1000 km, and the plantar pressure pattern during running may change as the shoe wears. So, the aim of this study was to determine the variation of plantar pressures with shoe wear, and the runner's subjective sensation. Maximun Plantar Pressures (MMP) were measured from 33 male recreational runners at three times during a training season (beginning, 350 km, and 700 km) using the Biofoot/IBV® in-shoe system (Biofoot/IBV®, Valencia, Spain). All the runners wore the same shoes (New Balance® 738, Boston, MA, USA) during this period, and performed similar training. The zones supporting most pressure at all three study times were the medial (inner) column of the foot and the forefoot. There was a significant increase in pressure on the midfoot over the course of the training season (from 387.8 to 590 kPa, p = 0.003). The runners who felt the worst cushioning under the midfoot were those who had the highest peak pressures in that area (p = 0.002). The New Balance® 738 running shoe effectively maintains the plantar pressure pattern after 700 km of use under all the zones studied except the midfoot, probably due to material fatigue or deficits of the specific cushioning systems in that area.

Comparative thermal map of the foot between patients with and without diabetes through the use of infrared thermography. / Mapa térmico comparativo del pie entre pacientes con y sin diabetes mediante el uso de termografía infrarroja.

OBJECTIVE: The objective of the study is to analyze, through the use of infrared thermography, the variability of foot temperature in diabetic and non-diabetic patients by segmenting the sole of the foot in four study areas. METHOD: A cross-sectional study was proposed on a sample of 479 subjects divided into two groups, a group of people with diabetes and a group of people without diabetes. The diabetes group comprised a total of 277 people, with an average age of 63.41 years, [138 men (49.8%) and 139 women (50.2%)], and the group without diabetes comprised 202 individuals, with an average age of 61.92 years, [99 men (49%) and 103 women (51%)]. The images were taken using the FLIR E60bx® camera. IBM SPSS Statistics 22 software was used for the statistical data analysis. RESULTS: The results show temperature variability in the different areas of study of the sole of the foot bilaterally and there were also differences according to whether the patient belonged to the diabetic or the non-diabetic group. CONCLUSIONS: The use of infrared thermography in the evaluation of the foot at risk could demonstrate the variability of temperature by study area, which could be useful in the area of healthcare for the diagnosis and prevention of injuries to compromised areas of the foot.

Age Estimation Based on a Radiographic Study of the Growing Foot.

BACKGROUND: We sought to determine a predictive model of data, differentiated by sex, from a radiographic study of the skeleton of the foot as an alternative to the classic study of the hand. METHODS: The study included 2,476 digital radiographs from 816 participants aged 0 to 21 years. The radiographs were from the Radiology Diagnostic Services of the Public Health System of Extremadura (Spain) from 2007 to 2011. The method used for their analysis consisted of assigning a numerical code to each ossification center of each growing bone of the foot and subsequently subjecting the data to a multivariate, decision tree, statistical analysis. RESULTS: The decision tree study identified the bones that have a common age-dependent pattern of growth (as determined by a comparison of means test with P < .01) among individuals of the same sex. The quality of the decision tree predictions was evaluated in terms of the r 2 coefficient. These values were r2 = 0.897 for females and r2 = 0.890 for males, thus establishing the predictive goodness of the model of bone data to provide a specific estimate of the individual's age. CONCLUSIONS: The foot is a good predictor of an individual's age from birth to complete bone maturity.

Calcaneal Bone Mass Modification in Recreational Runners.

BACKGROUND: The calcaneus is the bone of the foot that first receives the impact of running, generating vibrations that might have a positive effect in modifying the trabecular bone mass. The objective of this study was to determine the variation in calcaneal bone density in runners during a 6-month training season, comparing it with a control sample. METHODS: Bone density of the heel was measured in 33 male recreational runners by means of a contact ultrasonic bone analyzer. Measurements were made on three occasions during a training season: at the beginning, at 350 km, and at 700 km. All of the runners wore the same model of running shoes during this period. Measurements of bone density were also made in a control sample of 62 men who did not engage in physical exercise. RESULTS: There was a significant decrease in mean calcaneal bone density over the course of the training season (from 86.1 dB/MHz to 83.2 dB/MHz; P = .006), but no significant differences with the control sample value (from 80.7 dB/MHz to 81.1 dB/MHz; P = .314). The runners' body composition changed during the study period, with lean mass increasing and fat mass decreasing. CONCLUSIONS: Distance running seems to have a negative effect on calcaneal bone mass density during the course of a 700-km training season.

The foot posture index in men practicing three sports different in their biomechanical gestures.

BACKGROUND: The technical gestures characteristic of certain sports may lead to one type of foot being more prevalent than the others. The Foot Posture Index (FPI) has been used as a diagnostic tool for support postures in various sports, but the differences in these postures between sports of distinct gestures in their actions are far from completely understood. METHODS: The overall FPI, obtained as the sum of the scores of its six individual criteria, was determined in 90 male athletes (30 runners, 30 basketball players, and 30 handball players) in static bipedal stance and relaxed position. Analysis of variance was used to find significant differences among the three sports in the total FPI and its six criteria. RESULTS: The mean ± SD FPI was 2.9 ± 2.8 in runners, 3.9 ± 4.1 in basketball players, and -0.4 ± 6.9 in handball players, with significant differences among these groups (P = .008). Significant differences were also found in the talar head position and talonavicular prominence values between handball players and runners (P = .001 and P = .004, respectively) and between handball and basketball players (P = .002 and P = .006, respectively). CONCLUSIONS: Runners and basketball players had neutral feet, whereas handball players had supinated feet. The differences in foot posture seem to be mainly determined by two of the FPI criteria: talar head position and talonavicular prominence.

Comparison of plantar pressures and contact area between normal and cavus foot.

BACKGROUND: In pes cavus, the medial longitudinal arch elevation reduces the contact surface area and consequently increases the corresponding plantar pressure measurements. This poor distribution of loads may produce associated pathology and pain in this or other areas of the body. Normal reference values need to be established in order to determine which patterns are prone to pathology. OBJECTIVES: To compare the plantar pressures and weight-bearing surface in a population with pes cavus to a population with neutral feet. METHOD: The sample comprised 68 adults, 34 with pes cavus and 34 with neutral feet. The Footscan USB Gait Clinical System(®) was used as a platform to measure the total contact area and plantar pressure under the forefoot, midfoot, hindfoot, each metatarsal head, and the overall metatarsal area. A statistical analysis of the data was performed using Student's t-test for independent samples. RESULTS: The pes cavus subjects showed a significant reduction in their weight-bearing area [neutral feet: 165.04 ( ± 20.68) cm(2); pes cavus: 118.26 ( ± 30.31) cm(2); p < 0.001] and significantly increased pressures under all zones of the forefoot except the fifth metatarsal [metatarsal pressure: in neutral feet 503,797 ( ± 9.32) kPa; in pes cavus 656.12 ( ± 22.39) kPa; p < 0.001]. CONCLUSIONS: Compared to neutral feet, pes cavus feet show a reduction in total contact surface and the load under the first toe. A significant increase is present in the load under the metatarsal areas, but the relative distribution of this load is similar in both groups.

The foot posture index: anthropometric determinants and influence of sex.

BACKGROUND: The Foot Posture Index (FPI) quantifies foot posture on the basis of six criteria. Although the male foot is longer and broader than the female foot, limited evidence exists about the differences in foot posture between the sexes and which are its biological and anthropometric determinants. We sought to evaluate possible sex differences in the FPI and the determinants influencing foot posture. METHODS: In 400 individuals (201 men and 199 women), the FPI was determined in the static bipedal stance and relaxed position. The FPI was obtained as the sum of the scores (-2, -1, 0, 1, or 2) given to each of six criteria. A multiple regression model was constructed of the overall FPI against age, weight, height, body mass index, and foot size. RESULTS: The mean ± SD FPI was 2.0 ± 4.3 overall, 1.6 ± 4.5 for men, and 2.4 ± 4.1 for women, with the difference being nonsignificant (P = .142). The neutral posture was the most frequent (57.3%). A greater proportion of women had neutral and pronated feet, and a greater proportion of men had supinated and highly supinated feet, with the differences being nonsignificant (P = .143). Foot size, height, and body mass index together explained 10.1% of the overall FPI value (P < .001). CONCLUSIONS: The most frequent posture was neutral with a certain degree of pronation, with no differences in FPI values between men and women. Participants with larger foot sizes had higher FPI values, whereas taller and heavier participants had lower FPI values.

Effectiveness of neuromuscular stretching with symmetrical biphasic electric currents in the cavus foot.

BACKGROUND: Pes cavus is a structural deformity in which the increased plantar arch can lead to greater metatarsal verticality with the consequent excess of pressure under the forefoot zone (especially the metatarsal zone), causing pain and significant loss of functional capacity. We sought to determine whether neuromuscular stretching with symmetrical rectangular biphasic currents can reduce the pressure supported by this zone. METHODS: This prospective, nonrandomized, longitudinal, analytical, and experimental controlled trial included 34 patients with pes cavus. Pedobarometric measurements were made using the footscan USB Gait Clinical System platform considering the toes and metatarsal heads, forefoot, midfoot, and hindfoot before and after performing stretching using a Med Tens 931 electrotherapy device. The measurements were repeated 7 days after the application. RESULTS: With the Student t test for paired samples, we showed that there was a significant decline in metatarsal pressure (P < .001) in the zones of the first (P = .045) and third (P = .01) metatarsals and that this reduction was maintained 1 week after the plantar stretching. CONCLUSIONS: Plantar stretching with symmetrical rectangular biphasic currents is effective for the prevention and treatment of pes cavus metatarsalgia caused by excessive pressure.

The effect of moderate running on foot posture index and plantar pressure distribution in male recreational runners.

BACKGROUND: Fatigue due to running has been shown to contribute to changes in plantar pressure distribution. However, little is known about changes in foot posture after running. We sought to compare the foot posture index before and after moderate exercise and to relate any changes to plantar pressure patterns. METHODS: A baropodometric evaluation was made, using the FootScan platform (RSscan International, Olen, Belgium), of 30 men who were regular runners and their foot posture was examined using the Foot Posture Index before and after a 60-min continuous run at a moderate pace (3.3 m/sec). RESULTS: Foot posture showed a tendency toward pronation after the 60-min run, gaining 2 points in the foot posture index. The total support and medial heel contact areas increased, as did pressures under the second metatarsal head and medial heel. CONCLUSIONS: Continuous running at a moderate speed (3.3 m/sec) induced changes in heel strike related to enhanced pronation posture, indicative of greater stress on that zone after physical activity. This observation may help us understand the functioning of the foot, prevent injuries, and design effective plantar orthoses in sport.

Can the Foot Posture Index or their individual criteria predict dynamic plantar pressures?

The Foot Posture Index (FPI) quantifies foot posture through the evaluation of six individual criteria. The objective of the present study was then to establish the plantar pressure differences between types of feet, and to study the capacity of the whole FPI value and the six individual criteria to predict the pattern of plantar pressures. In a sample of 400 healthy subjects (201 men and 199 women), the FPI was evaluated and plantar pressures were measured in 10 zones using the Footscan(®) platform. Five plantar pressures measurements were made for each foot, using for the study the mean of these measurements for each subject's left foot. The hallux and the lesser toes had lower pressure indices in highly supinated feet, with the values increasing progressively toward the highly pronated feet (p<0.001 and p=0.019 respectively). The fifth metatarsal head (MTH) values were greater in highly supinated feet, and decreased in the highly pronated feet (p<0.001). The FPI value predicts low variability of plantar pressures, mainly in the heel and midfoot, while the individual criteria predict higher variability in the forefoot. The talonavicular prominence and the calcaneal frontal plane position was the most influential criterion, explaining 8.5% of the hallux pressure and 11.1% of the fifth MTH pressure. Neither talar head palpation nor the supra and infra malleolar curvature predicted any of the plantar pressures variables. The FPI can distinguish three groups of feet--pronated, neutral, and supinated. Its individual criteria predict moderate or low plantar pressures variability, with the talonavicular prominence being the most influential criterion.