Dominant Foot Research Articles

Effect of foot anthropometric measurements on postural stability

Aim: To examine the effect of foot anthropometric measurements and body sizes of young male adults with normal posture on balance. Methods: In this study, the effect of body size and foot anthropometric measurements of 112 young male adults with normal posture on balance was investigated. The foot and body parameters of the cases were measured. The static and the dynamic balance tests were evaluated according to the dominant foot in each case. The parameters that affected balance were determined and the variables were taken to the model. In addition, the significance levels that defined the effects of the properties examined in relation with the balance were also calculated. Results: When the findings were evaluated, it was determined that the effect of the foot parameters other than the foot length, and the effect of 15 body parameters other than the biiliac diameter, trochanteric height, and right upper extremity length on balance performance was significant. The balance test performance was predicted with success ranging from 7.8% to 43% with the parameters included in the model. Conclusion: In this study, the fact that the relation between the foot anthropometric and body dimensions and functional balance performances of young male adults was found to be significant shows that this relation must be considered in the creation of a normative database on balance, and in clinical studies that will be conducted on the subject.

How Dominant Hand and Foot Dexterity May Reveal Dementia Onset: A Motor and Cognitive Dual-Task Study.

The combined provision of an arising number of dementia cases, and the substantial absence of effective treatments, led the scientific community toward the identification of early phases of this condition. Such an effort aims at the recognition of therapeutic windows and the characterization of the disease's different grades. In the last years, Motor and Cognitive Dual-Tasks (MCDT) have been widely used to address the early diagnosis of several neurocognitive disorders, among which dementia. Here we present different protocols: the walking MCDT, the toe-tapping MCDT, and the forefinger-tapping MCDT. Moreover, each task has been performed under different cognitive conditions: no cognitive effort, counting backwards by 1, 3, and 7. In this work, we report the results obtained through the combination of different motor and cognitive tasks, and we present 2 brand-new MCDT protocols, attempting to identify a sweet-spot for early diagnosis of dementia.

How manipulation of playing area dimensions in ball possession games constrains physical effort and technical actions in under-11, under-15 and under-23 soccer players

ABSTRACT The aim of this study was to investigate the effects of playing area manipulation (20 × 15 m, 25 × 20 m and 30 × 25 m) on external workloads (total distance covered, distance covered while walking, running and sprinting, number of sprints, maximum sprint speed), internal load perceptions (rating of perceived exertion) and technical actions of passing (number of passes with dominant and non-dominant foot, and maximum passing speed) during 4v4 ball possession small-sided and conditioned games in under-11, under-15 and under-23 soccer players. Results showed higher values in the large playing area for under-11 in the distance covered in different speed zones, sprint number and RPE (all p <.001) for under-15 in sprints number (p <.01) and maximum sprint speed (p =.02), and for under-23 in both RPE and sprint numbers (p <.01). Although no significant differences were found on technical actions, it was still possible to notice some effects through pairwise comparison. High-intensity running was promoted on larger playing areas, where under-11 s were also able to perform more technical actions of passing. Opposite, under-23s were able to perform more passing on smaller playing areas, where under-11 s perceived the exercise more intense. The impact of different playing areas was reduced for the under-15.

Effect of prefabricated thermoformable foot orthoses on plantar surface temperature after running: A gender comparison.

There is a lack of evidence about the effect of different type of foot orthoses on plantar surface temperature. Moreover, that effect could be different depending on gender due to anatomical and physiological differences between men and women. The aim of the study was to analyze the effect of a prefabricated thermoformable foot orthosis on plantar surface temperature after running and taking gender differences into account. Thirty recreational runners (15 males, mean (standard deviation): 28 (7) years, 69.7 (6.5) kg, 1.74 (0.05) cm and 22.9 (1.7) kg/m2; and 15 females: 35 (7) years, 55.2 (6.9) kg, 1.63 (0.06) cm and 20.6 (1.9) kg/m2) carried out a maximum incremental test as pre-test, and two running tests on a treadmill at the laboratory wearing previously randomized different foot orthoses (thermoformable and prefabricated generic). The plantar surface temperature of the dominant foot sole in ten regions of interest was assessed before and immediately after 30-min running at 75% of VO2max. The use of thermoformable foot orthoses produced lower temperatures only in men after the run in medial heel (P=0.033, ES=0.7), which then disappeared in temperature variation (after - before) (P=0.910). Regarding gender, women showed lower temperatures before the run in both orthosis conditions (P<0.039, ES>0.8), but no differences in temperatures after the run (P=0.910) in comparison with men. Moreover, absolute temperatures after running were always greater than before the run (P<0.001, ES>5.0). In conclusion, the thermoformable foot orthoses do not modify plantar surface temperature after running in healthy runners of either gender, compared to prefabricated generic foot orthoses. Although women present lower baseline plantar temperatures than men, these differences disappear after exercise.

Effect of the teaching model on the individual technique of soccer players sub-10

El objetivo del estudio fue comparar el efecto del modelo de enseñanza en la mejora de la técnica individual en ambas piernas de jugadores de fútbol sub-10. Se analizaron a 12 jugadores que realizaron ocho sesiones con un modelo tradicional y ocho con un modelo moderno. Se midió: pase, control, conducción y golpeo de balón. El modelo tradicional mejora el pase y golpeo con la derecha y la conducción de balón con ambos pies, con diferencias significativas (p&lt;.05) en el pase con derecha y la conducción de balón con ambas piernas. En el modelo innovador mejora el pase con pie dominante, la conducción lineal con ambos pies y el golpeo de balón a portería con ambos pies, con diferencias significativas en la conducción de balón con ambas piernas (p&lt;.05). Por estos motivos, la mejora de la técnica individual de los jugadores necesita de la utilización modelos tradicionales e innovador. The aim of the study was to compare the effect of the teaching model on the improvement of individual technique in both legs of soccer players sub-10. We analyzed 12 players who made eight sessions with a traditional model and eight with an innovative model. It was measured: pass, control, driving and hitting the ball. The traditional model improves the pass and hit with the right and the ball driving with both feet, with significant differences (p &lt;.05) in the right pass and the ball driving with both legs. In the innovative model improves the pass with dominant foot, linear driving with both feet and hitting the ball on goal with both feet, with significant differences in the driving of the ball with both legs (p &lt;.05). For these reasons, the improvement of the individual technique of the players requires the use of traditional and innovative models.

Importance of the Rear and Non-dominant Leg in Supporting the Body in Tandem Stance

Objective: Some studies have reported that postural assessment of a narrow base of support such as the tandem stance is useful in evaluating the risk of falls. The purpose of the present study was to obtain maximum inter-foot distance (IFD) during crossover movement of the rear foot from tandem stance, and to compare these data with those of our previous study of the front leg moving across the front of the body. Methods: Forty healthy young people were recruited as subjects (aged 29 ± 6 years, 19 men). The subjects moved their rear leg across the rear of their body according to split treadmill belt movement. Maximum IFD was measured by a three-dimensional motion analysis system and defined as the largest IFD such that either foot could be removed from the treadmill belt while maintaining a standing posture. Four conditions were set for the measurements: the rear leg was dominant and non-dominant under two treadmill belt velocities (0.5 km/h and 1.0 km/h). Two-way analysis of variance was used for the analysis. Results: Normalized maximum IFD (NMIFD) was 8-9% of subject height. Interaction between the rear leg and treadmill belt velocity was not significant. There was no significant main effect of treadmill belt velocity and the dominant foot on NMIFD. Comparing the results of our previous study, under the condition of the dominant foot moving, the NMIFD of the front leg moving across the front of the body was significantly larger than that of the rear leg moving across the rear of the body. Conclusion: The function of the rear leg is important as a support under the condition of crossing the legs from a standing posture such as tandem stance.

Match performance in a reference futsal team during an international tournament - implications for talent development in soccer.

Anecdotal evidence suggests that futsal can aid talent development for 11 a-side soccer through the potential for transfer of the game’s skills and constraints. However, additional scientific research is necessary to enhance understanding of the technical and physical demands of futsal and the potential returns for soccer player development. Accordingly, this study examined selected characteristics of physical (internal and external loads) and technical performance in international futsal match-play in order to study the potential of these for skill transfer and aiding soccer player development. Performance was investigated in futsal players (n = 16, 25.74±4.71 years) belonging to a national team during an international tournament. Pre-tournament fitness testing determined maximum heart rate (MHR) via the Yo-Yo IR1 test (194.6±11.1 beats min-1) to aid interpretation of internal load via heart rate measures during match-play. External load (accelerations and deceleration events) was measured using an inertial movement unit. Finally, post-tournament analysis of selected technical events was performed. Results reported a mean heart rate value during ‘court time’ of 164.7±22.3 beats min-1, which as a percentage of participants’ MHR was 87.7%±4.4%, and a mean peak MHR of 98.3±2.5%. Results showed 2.16±0.25 accelerating (>1.5 m·s-2) and 2.78±0.13 decelerating (>1.5 m·s-2) events per player per minute. Team statistics included 647 passing, ~51 dribbling and 78 set play events per team per game. Match analyses showed that 77.3% of ball receptions were completed with the sole of the foot. Assessment of two-footedness showed 80.1±16.7% of individual possessions used the dominant foot to receive and 84.1±10.7% to pass the ball thereby displaying strong foot dominance. These results have quantified characteristics of elite futsal match-play that are no doubt intrinsically related to the environmental and task constraints of the sport. In addition to enhancing understanding of futsal, there are potential learning returns and implications for skills transfer and the development of soccer players.

The effects of gait speed on plantar pressure variables in individuals with normal foot posture and flatfoot

It is not known how gait speed affects plantar pressure characteristics in flatfoot. The aim of this work was to investigate the effects of gait speed on plantar pressure variables in flatfoot by comparing it to normal foot posture. Thirty individuals with flatfoot and 30 individuals with normal foot posture were recruited. Plantar pressure variables were obtained by a pressure-sensitive mat at self-selected slow, normal, and fast speeds. All assessments were performed on the dominant foot, and three satisfactory steps were obtained for each gait speed condition. The order of gait speeds was randomized. In the flatfoot group, the contact area was higher in the midfoot, third metatarsal, and hallux at all speeds, also in the second metatarsal at slow and normal speeds than the normal foot posture group ( p < 0.05). The maximum force was higher in the midfoot and hallux at all speeds in the flatfoot group ( p < 0.05). Also, the maximum force was lower in the first metatarsal at normal and fast speeds, and in the lateral heel at fast speed ( p < 0.05). In the flatfoot group, the peak pressure was found to be higher in the hallux at slow speed, but to be lower in the first metatarsal at fast speed ( p < 0.05). Further, plantar pressure distribution was affected by gait speed in both feet. Analysis of plantar pressure variables should be performed at different gait speeds.

Competitiveness, Gender and Handedness: A Large-Sample Intercultural Study

We conduct a large-scale intercultural experiment to elicit competitiveness and ask whether individual and gender differences in competitiveness are partially determined by nature. We use being a “lefty” (i.e., having either a dominant left hand or a dominant left foot) as a proxy for nature, as it is associated with neurological differences which are determined prenatally and reflects a masculinized neurology. That way we use handedness and footedness as a proxy for innate differences. In large-scale data with incentivized choices from 3683 participants from India, Norway and Tanzania, we find a significant gender gap in competitiveness in all cultures. However, we find inconsistent results when comparing the competitiveness of lefties and righties. In northeast India we find that lefties of both genders are significantly more competitive than righties. In Norway we find that lefty men are more competitive than any other group, but women’s competitiveness is not related to handedness or footedness. In Tanzania, we find no effect of handedness or footedness on the competitiveness of either gender. The merged data show weak evidence of a positive correlation between being a lefty and competitiveness for men, but no such evidence for women. Thus, our data do not provide robust evidence that gender differences in competitiveness are partially determined by nature, where nature is represented by the complex, physiologically-rooted phenomenon of handedness.

The Difference of In-Shoe Plantar Pressure Between Level Walking and Stair Walking

Category:Basic Sciences/BiologicsIntroduction/Purpose:Stair walking is one of common activities of daily living. It is more demanding than level walking and can aggravate discomfort of the foot, such as Morton’s neuroma, plantar fasciitis, Achilles tendinitis, pressure related-ulcer, and etc. Therefore, analysis of increased pressure in specific plantar area at stair walking can be used as a risk assessment of foot discomfort and basic data in the clinical field. The purpose of this study is to analyze plantar pressure distribution and pressure patterns during gait cycle at stair walking compared to level walking.Methods:Fourty healthy male adults were recruited. Radiologic measurements and gait analysis were performed to check participants’ normality, and 35 healthy males with 20-28 years old were included. They performed level walking (18 meters walkway), stair (26 steps stair, height:16.7 cm, depth:29.8 cm) ascending, and descending in same type of running shoes.Measurements of in-shoe plantar pressure including peak pressure, pressure-time integral (PTI) were done by Pedar-X system. Only measurements of right steps were used to exclude the effect of the dominant foot. The sole was masked in 7 segments (hallux, 2nd-5th toes, medial forefoot, central forefoot, lateral forefoot, midfoot, heel region) to analyze properly. Percentages were assigned in relation to the size for each mask segment. Statistical analysis was performed using repeated measure ANOVA, and Bonferroni post hoc test was done.Results:Mean peak pressures in all regions except for the midfoot were higher during level walking than stair walking. During stair descent, mean peak pressures in all the regions except for the midfoot were generally lower than other types of walking, but it was the highest in the midfoot region. Pressure time integral (PTI) in the medial and central forefoot was higher during stair descent than level walking. PTI in the central and lateral forefoot, and the midfoot was higher when stair ascending than level walking. Pressure time integral (PTI) in the heel region was the highest during level walking, followed by stair ascent, stair descent.Conclusion:The risk of aggravation of discomfort in the midfoot area increases when stair descending. The medial region of forefoot bear high pressure load during stair descent, and the lateral region of forefoot and the midfoot region bear high pressure load during stair ascent.This is the first study to show plantar pressure patterns during level and stair walking in the large healthy gender-controlled population. We recommend that patients with pressure related foot lesions in the forefoot or midfoot avoid stair walking.

Comparing Balance Control Between Soccer Players and Non-Athletes During a Dynamic Lower Limb Reaching Task

ABSTRACTBackground: Balance control is an essential element of locomotion that enhances biomotor abilities and physical performance. Individuals with extensive soccer experience display superior static single leg balance control compared to athletes of other sports as well as non-athletes. However, during a match, players often encounter greater challenges to single leg balance that require rapid decision-making skills and dynamic stability. Purpose: The purpose of this study was to determine if individuals with extensive soccer training demonstrate superior single-leg balance control compared to non-athletes during a dynamic lower limb reaching task. Method: 22 varsity soccer players were matched with 21 non-athlete controls. Single-leg balance control was assessed during a Go/No-Go lower limb reaching task. Centre of pressure displacement (dCOP) was measured for both the dominant and non-dominant feet and compared between groups. Results: Soccer players displayed reduced dCOP during All Go trials compared to non-athletes, particularly in the medial-lateral plane. Additionally, soccer players displayed reduced anterior-posterior dCOP during Go/No-Go trials compared to non-athletes, particularly on their dominant foot. Conclusion: Athletes with soccer-specific training demonstrate improved executive control and use of proprioceptive information, which results in an improved ability to maintain single-support balance and corral COP during a dynamic visuomotor lower limb-reaching task. As such, balance training may be a useful addition to athlete training regimes to improve sport-specific performance. Future research would compare these results to athletes of other sports to explore balance control during a visuomotor reaching task and how it may differ based on sport training history.

Relationships between adiposity and postural control in girls during balance tasks of varying difficulty

ObjectiveThis study aimed to examine associations between postural control and body composition in 8–10-year-old girls. MethodsAn observational cross-sectional study was conducted in 47 girls who were healthy-weight/overweight/obese [body mass index (BMI) percentile]. Girls participated in six postural control conditions of varying difficulty (standing with malleoli touching, tandem stance leading with dominant and non-dominant foot, repeated with eyes open and closed). Postural control outcomes included Centre of Pressure (COP) sway area, COP principal and minor axis length and COP maximum velocity. Data were analysed using linear mixed modelling. ResultsBMI percentile was positively associated with COP sway area (p=0.034) and principal axis (p=0.030) during tandem stance non-dominant foot leading with eyes closed and COP principal axis during tandem stance dominant foot leading with eyes open (p=0.045). BMI percentile significantly interacted with postural control conditions of varying difficulty to predict postural control outcomes (p≤0.035), notable for tandem stance positions [all four COP sway outcomes in tandem stance non-dominant foot leading eyes closed; tandem stance dominant foot leading with eyes open and closed (two COP sway outcomes each)]. ConclusionsGirls with greater adiposity may have impairments in postural control, but only during more challenging postural control conditions. In contrast, BMI has little role to play in girls’ postural control in easier postural control conditions (standing with feet together). These findings may suggest potential functional or safety considerations when girls with overweight/obesity are performing demanding postural control tasks (such as during sport or physical activity).

Validity of an instrumented sock and on-shoe sensor to provide biometric feedback to runners

Study Design: Validity study.Background: Run form analysis and retraining are commonly utilized in orthopaedic and sports medicine environments. New tools in running technology may assist clinicians in providing feedback to runners outside the clinic. These devices provide runners the capacity to analyse multiple characteristics of their stride, but little is known regarding the accuracy of their output.Objective: Investigate the validity of an instrumented sock and on-shoe sensor as compared to high-speed video analysis.Methods: Forty recreational runners completed a 10-minute treadmill run at a self-selected pace while wearing both devices. High-speed video allowed for the analysis of average running cadence and percentage of time in each foot strike pattern. Other variables of interest included running speed and distance. Intraclass correlation coefficients (ICC2,1) were calculated for all variables. A categorical classification of dominant foot strike pattern was utilized, with Cohen’s kappa describing agreement of the devices to video analysis.Results: The instrumented sock’s ICCs were 0.40 for speed, 0.46 for distance, 0.97 for cadence and 0.40 for foot strike pattern. The on-shoe sensor generated ICCs of 0.86 for speed, 0.86 for distance, 0.99 for cadence and 0.91 for foot strike pattern. Cohen’s kappa values for foot strike pattern agreement were 0.35 for the sock and 0.79 for the on-shoe sensor.Conclusion: The instrumented sock demonstrated valid measurement of running cadence, but potential product design limitations reduced accuracy on the other study variables. The on-shoe sensor utilized in this study provided valid post-run feedback across measures of speed, distance, cadence and dichotomous classification of foot strike pattern.

Effects of fine plantar stimulation in bilateral pelvic instability: Preliminary study

Introduction This study experiments the incidence of a 2 mm thin median bar (BM®) and truncated median bar (BMt®) plantar relief in bilateral pelvic instabilities, considering the effect of the presence or not of plantar afferences inefficiency on unipedal stabilometric performance [1] . Method Eleven subjects with bilateral pelvic instability at the unipedal pelvic stability test (TSPU) [1] and with a right dominant foot were evaluated. Randomized measurements were performed in bipodal stance on force platform (Medicapteurs©, Fusyo®, France) for 31.6 sec at 40 Hz and then in unipedal stance for 5 sec at 40 Hz on each foot, eyes open and eyes closed under three conditions: – Control; – BM® – BMt®. Repeated and factorial variance analyses were then carried out. The population was divided into two groups according to their Plantar Quotient (PQ) greater or less than 100 determined by the bipodal registrations [2] . Results Seven subjects showed a QP greater than 100 and 4 subjects a QP less than 100. The BM® and BMt® stimuli enhanced the Surface of the Centre of Pressure (CoP) on the right foot with eyes closed. Taking into account the QP, subjects with a QP greater than 100 were enhanced on the surface of the CoP with BMt® only. In this condition, both median bars (BM® and BMt®) enhanced the subjects if their QP was less than 100. Conclusion This study on bilateral pelvic instabilities with thin plantar stimuli confirms their therapeutic interest in these dysfunctions of postural control and illustrates fundamental interest of two notions: – foot dominance and; – efficiency or inefficiency of plantar afferences. These results require further research that considers these intra and inter individual differences.

Stabilometric objectification of pelvic instabilities discriminated against by the Unipodal Pelvic Stability Test (UPST)

Introduction The purpose of this study was to determine whether the UPST was objectived by stabilometric parameters in both bipodal and unipodal stations. Method Twenty-six women, 15 men, average age 34 ± 6.9 years, are divided into 2 groups by an expert practitioner according to the results of the UPST. They were then evaluated in bipodal stance on force platform (Medicapteurs©, Fusyo®, France) for 31.6 sec at 40 Hz, under 4 conditions: – open eyes; – closed eyes; – open eyes with foam and; – closed eyes with foam (Capitoner® 8sh 2 mm). Subjects were recorded in unipodal situation for 5 sec at 40 Hz on the left and right feet, eyes open and eyes closed. All registrations were randomized and volunteers with a dominant left foot (2) or a UPST dysfunction on the left were excluded (4). Data analysis was performed by two MANOVA for each experimental time. Results Subjects with bilateral instability to the UPST showed a significantly larger surface area of the Centre of Pressure in the bipodal situation with eyes closed (F (2.32) = 4.48; P = 0.02 (η2 = 0.22)) and in unipedal situation with eyes open, only on the left foot (F (2.32) = 5.7; P = 0.008 (η2 = 0.26)) compared to volunteers without pelvic instabilities. The subjects with right dysfunctions to the UPST showed no significant difference in stabilometric parameters compared to the control population. Conclusion Subjects with bilateral pelvic instability have poorer postural stability in both bipodal and unipedal stance while isolated right pelvic instability cannot be characterized by force platform exams.

Comparison of Quadriceps Q-Angle Values of Soccer Players and Wrestlers

The aim of this study is to compare according to different positions the mean right and left knee Q angle of footballers and wrestlers. In this study, found the female soccer and wrestlers mean age 20.51 ± 3.47 years, height 165.43 ± 4.82 cm, weight 58.23 ± 5.18 kg. Male soccer and wrestlers has with mean age 21.30 ± 3.45 years, height 173.28 ± 5.45 cm, weight 65.66 ± 5.73 kg. One-way ANOVA, Student t, and Duncan post hoc test were used for statistical analysis. In this study, found that the mean right and left knee Q angles of male athletes were 15.08 ± 1.79° and 14.49 ± 1.82° for the standing position, 14.26 ± 1.84° and 13.29 ± 1.82° for the supine position.The mean right and left knee Q angles of Female athletes were 18.11 ± 1.32° and 17.90 ± 1.35° for the standing position, 17.52 ± 1.36°and 16.82 ± 1.29° for the supine position. In this study, were found abnormal results. The difference between the Q angle values of footballers and wrestlers was found to be statistically significant (p &lt;0.001). The Q angle values for male soccer players were found 15.35 for standing right Q angle and 15.12 degrees for standing left Q angle and same values 14.80 and 13.86 degrees in the male wrestlers. Q angle values for women footballers were found 17.32 decrees for standing right Q angle and 17.22 degrees for standing left Q angle, and same values 18.90 and 18.58 degrees in the women wrestlers. Standing and supine Q angle values of Wrestlers in both men and women were found to be wider than the Q angle values of soccer athletes (p&lt;0.001). The right Q- angle values of the athletes in the standing and supine position were found higher than the left Q-angle values (p &lt;0.05).Conclusion: The Q angles were within the normal range for footballers and wrestlers. In standing positions Q angle is higher than from supine positions Q angle. Athlete's sex, pelvic width, tibia and femur length and dominant foot may increase the quadriceps Q angle.

Lateralization (handedness) in Magellanic penguins.

Lateralization, or asymmetry in form and/or function, is found in many animal species. Brain lateralization is considered adaptive for an individual, and often results in “handedness,” “footedness,” or a side preference, manifest in behavior and morphology. We tested for lateralization in several behaviors in a wild population of Magellanic penguins Spheniscus magellanicus breeding at Punta Tombo, Argentina. We found no preferred foot in the population (each penguin observed once) in stepping up onto an obstacle: 53% stepped up with the right foot, 47% with the left foot (n = 300, binomial test p = 0.27). We found mixed evidence for a dominant foot when a penguin extended a foot for thermoregulation, possibly depending on the ambient temperature (each penguin observed once). Penguins extended the right foot twice as often as the left foot (n = 121, p < 0.0005) in 2 years when we concentrated our effort during the heat of the day. In a third year when we observed penguins early and late in the day, there was no preference (n = 232, p = 0.59). Penguins use their flippers for swimming, including searching for and chasing prey. We found morphological evidence of a dominant flipper in individual adults: 60.5% of sternum keels curved one direction or the other (n = 76 sterna from carcasses), and 11% of penguins had more feather wear on one flipper than the other (n = 1217). Right-flippered and left-flippered penguins were equally likely in both samples (keels: p = 0.88, feather wear: p = 0.26), indicating individual but not population lateralization. In fights, aggressive penguins used their left eyes preferentially, consistent with the right side of the brain controlling aggression. Penguins that recently fought (each penguin observed once) were twice as likely to have blood only on the right side of the face (69%) as only on the left side (31%, n = 175, p < 0.001). The proportion of penguins with blood only on the right side increased with the amount of blood. In most fights, the more aggressive penguin used its left eye and attacked the other penguin’s right side. Lateralization depended on the behavior tested and, in thermoregulation, likely on the temperature. We found no lateralization or mixed results in the population of Magellanic penguins in three individual behaviors, stepping up, swimming, and thermoregulation. We found lateralization in the population in the social behavior fighting.

Muscle activity and balance control during sit-to-stand across symmetric and asymmetric initial foot positions in healthy adults

BackgroundRising from a sit to a stand has biomechanical factors that are dependent on initial foot position. Little is known about the effect of initial foot position on leg muscle activation patterns during a sit-to-stand and balance maintenance of stance after a sit-to-stand. Research questionWhat are the effects of different symmetric and asymmetric initial foot positions on leg muscle activation patterns and balance during and after a sit-to-stand? MethodsThree symmetric (neutral; both ankles positioned under the knees at a 90° flexion; one-third; and two-thirds foot length posterior to neutral) and three asymmetric (neutral non-dominant leg with one-third back dominant leg, neutral non-dominant with two-thirds back dominant leg, and one-third back non-dominant leg with two-thirds back dominant leg) initial foot positions were tested. EMG of the lower extremity muscles and sagittal plane kinematic data were measured along with balance assessments in the anterior-posterior and medial-lateral axes. ResultsIn the symmetric initial foot positions, a faster forward velocity of the body’s center of mass was required for more anterior initial foot positions. Even though the hip extensors activated earlier to decelerate the forward velocity of the body’s center of mass before rising, the greater forward velocity caused postural sway following completion of upright stance. In the asymmetric initial foot positions, the posterior leg supported more weight during the sit-to-stand, resulting in balance perturbations in the posterior leg. In the one-third back non-dominant leg with two-thirds back dominant leg asymmetric initial foot position, however, the weight-bearing symmetry was not different from the symmetric initial foot positions during the sit-to-stand. Postural stability after completion of uprising was also improved in this asymmetric initial foot position, showing greater but delayed onset of the tibialis anterior in the anterior leg during the momentum transfer phase. SignificanceWith a neutral symmetric initial foot position, earlier onset of the hip extensors during eccentric lengthening contributed to decelerating the forward velocity of the body’s center of mass for balance control during a sit-to-stand. With asymmetric initial foot positions, the weight distribution during a sit-to-stand can be increased by positioning both feet posterior to neutral foot position. Performing a sit-to-stand with this asymmetric initial foot position can improve postural stability after uprising. Thus, this foot position could be used in designing rehabilitation interventions for clinical populations and the frail elderly.

Predictive value of the risk factors for amputation of lower extremity in patients with diabetic foot in Al-Karama teaching hospital

Background: Diabetic foot disease is a foot that exhibits any pathology that results directly from diabetic mellitus or any long-term chronic complication of diabetes mellitus. The aim of the study was to determine the risk factors and indications for amputations among diabetics.Methods: this clinical prospective study includes 120 diabetic foot patients admitted to AL- Karama teaching hospital from 1st January 2015 to 1st January 2019. All patients assessed for age, gender, duration of diabetes, hyperglycemia at admission and control of diabetes, history of smoking, hypertension, assess dominant foot and examination of diabetic foot lesion and classify it according to Meggit-Wagner grading status, indications for amputation and outcome.Results: The male to female ratio was 2:1. Most frequent age group of patients treated by amputation was between 50-80 years. Among patients treated with amputation (68.33%) of patients had diabetes mellitus for 11-20 years. From patients admitted with diabetic foot (53.33%) were smokers. Regarding hypertension (93.33%) of all patients were hypertensive. It was noted that (65%) of patients lesion occur in dominant foot Regarding Wagner's grading system (36.66%) of patients were grade 4 followed by grade 1 (21.66%). regarding mode of treatment (53.33%) of patients treated by amputation and other treated conservatively. Only 3 patients from 60 died while other discharged well after complete treatment.Conclusions: Increasing in age, long duration of diabetes mellitus, poor control of diabetes, smoking and occurrence of lesion in dominant foot all considered as a significant risk factors for increase liability amputation.

Divergent effects of conditioned pain modulation on subjective pain and nociceptive-related brain activity.

Pain is a complex experience involving both nociceptive and affective-cognitive mechanisms. The present study evaluated whether modulation of pain perception, employing a conditioned pain modulation (CPM) paradigm, is paralleled by changes in contact heat-evoked potentials (CHEPs), a brain response to nociceptive stimuli. Participants were 25 healthy, pain-free, college students (12 males, 13 females, mean age 19.24 ± 0.97years). Twenty computer-controlled heat stimuli were delivered to the non-dominant forearm and CHEPs were recorded at Cz using a 32-channel EEG system. After each stimulus, participants rated the intensity of the heat pain using the 0-100 numerical rating scale. The latency and amplitude of N2, P2 components as well as single-sweep spectral analysis of individual CHEPs were measured offline. For CPM, participants had to submerge their dominant foot into a neutral (32°C) or noxious (0°C) water bath. CHEPs and heat pain ratings were recorded in 3 different conditions: without CPM, after neutral CPM (32°C) and after noxious CPM (0°C). The noxious CPM induced a facilitatory pain response (p = 0.001) with an increase in heat pain following noxious CPM compared to neutral CPM (p = 0.001) and no CPM (p = 0.001). Changes in CHEPs did not differ between conditions when measured as N2-P2 peak-to-peak amplitude (p = 0.33) but the CPM significantly suppressed the CHEPs-related delta power (p = 0.03). Changes in heat pain in the noxious CPM were predicted by trait catastrophizing variables (p = 0.04). The current study revealed that pain facilitatory CPM is related to suppression of CHEPs delta power which could be related to dissociation between brain responses to noxious heat and pain perception.