Mining work boot shaft stiffness and sole flexibility variations are likely to affect how a miner moves their foot to clear the ground thus influencing their risk of tripping. Despite the potential negative consequences associated with tripping, limited research has investigated how these boot design features might contribute to a miner's trip risk. Therefore, this study aimed to investigate the effects of systematic variations to boot shaft stiffness and sole flexibility on lower limb alignment and shank muscle activity at toe off and boot clearance during initial swing when 20 males walked across two simulated coal mining surfaces. Although knee and hip alignment remained constant, changes to boot shaft stiffness and sole flexibility significantly interacted to influence the shank muscle activity and ankle alignment displayed at toe off. To reduce the risk of tripping, underground coal miners should avoid a boot with a stiff shaft, regardless of the sole flexibility.
The structural features of work boots worn by underground coal miners affect comfort, foot motion and, in turn, loading of the plantar surface of miners' feet. Although shaft stiffness and sole flexibility appear to be boot design features that could influence perceived comfort and plantar pressures, no study has systematically altered these boot design features to truly understand how they affect these parameters. This study aimed to systematically investigate the effect of changes to shaft stiffness and sole flexibility on perceived comfort and plantar pressures when 20 males walked on a simulated gravel coal mining surface under four different work boot conditions. There were no significant effects of shaft stiffness or sole flexibility on perceived comfort. However, shaft stiffness and sole flexibility each significantly affected the plantar pressures generated under the medial midfoot, heel, middle metatarsals and hallux and, in combination, affected plantar pressures generated beneath the lateral midfoot, medial and lateral metatarsals and lesser toes. Participants preferred a boot with a flexible shaft combined with a stiff sole, citing properties such as fit, moveability, walking effort and support to explain why they perceived one boot as more comfortable than another. We therefore recommend that underground coal mining work boots should be designed to incorporate different flexibility and stiffness between the shaft and sole of the boot to optimise foot movement and, in turn, walking efficiency.
Design features of safety work boots have the potential to influence how underground coal miners' feet interact with the challenging surfaces they walk on and, in turn, their risk of slipping. Despite the importance of work boot design in reducing the risk of miners slipping, limited research has investigated how boot design features, such as shaft stiffness and sole flexibility, affect the way miners walk. Therefore, this study aimed to investigate the effects of systematic variations to boot shaft stiffness and sole flexibility on lower limb muscle activity and ankle motion in preparation for initial foot-ground contact when 20 males walked across two simulated coal mining surfaces under four mining boot conditions. It was concluded that a boot which has different flexibility and stiffness between the shaft and sole is a better design option to reduce underground coal miners' slip risk than a boot that has a stiff shaft and stiff sole or flexible shaft and flexible sole.
BACKGROUND:Clinical decision-making regarding diagnosis and management largely depends on comparison with healthy or 'normal' values. Physiotherapists and researchers therefore need access to robust patient-centred outcome measures and appropriate reference values. However there is a lack of high-quality reference data for many clinical measures. The aim of the 1000 Norms Project is to generate a freely accessible database of musculoskeletal and neurological reference values representative of the healthy population across the lifespan. METHODS/DESIGN:In 2012 the 1000 Norms Project Consortium defined the concept of 'normal', established a sampling strategy and selected measures based on clinical significance, psychometric properties and the need for reference data. Musculoskeletal and neurological items tapping the constructs of dexterity, balance, ambulation, joint range of motion, strength and power, endurance and motor planning will be collected in this cross-sectional study. Standardised questionnaires will evaluate quality of life, physical activity, and musculoskeletal health. Saliva DNA will be analysed for the ACTN3 genotype ('gene for speed'). A volunteer cohort of 1000 participants aged 3 to 100 years will be recruited according to a set of self-reported health criteria. Descriptive statistics will be generated, creating tables of mean values and standard deviations stratified for age and gender. Quantile regression equations will be used to generate age charts and age-specific centile values. DISCUSSION:This project will be a powerful resource to assist physiotherapists and clinicians across all areas of healthcare to diagnose pathology, track disease progression and evaluate treatment response. This reference dataset will also contribute to the development of robust patient-centred clinical trial outcome measures.
Certain styles of children’s shoes reduce 1st metatarsophalangeal joint (MTPJ) and midfoot motion during propulsion of walking. However, no studies have investigated if the splinting effect of shoes on children’s 1st MTPJ and midfoot motion occurs during running. This study investigated the effect of sports shoes on multi-segment foot kinematics of children during propulsion of walking and running. Twenty children walked and ran at a self-selected velocity while barefoot and shod in a random order. Reflective markers were used to quantify sagittal plane motion of the 1st MTPJ and three-dimensional motion of the midfoot and ankle. Gait velocity increased during shod walking and running and was considered a covariate in the statistical analysis. Shoes reduced 1st MTPJ motion during propulsion of walking from 36.0° to 10.7° and during running from 31.5° to 12.6°. Midfoot sagittal plane motion during propulsion reduced from 22.5° to 6.2° during walking and from 27.4° to 9.6° during running. Sagittal plane ankle motion during propulsion increased during shod running from 26.7° to 34.1°. During propulsion of walking and running, children’s sports shoes have a splinting effect on 1st MTPJ and midfoot motion which is partially compensated by an increase in ankle plantarflexion during running.
BACKGROUND:Charcot-Marie-Tooth disease is an inherited neuropathy causing progressive weakness, foot deformity and difficulty walking. Clinical anecdotes suggest orthoses designed on the 'sensorimotor' paradigm are beneficial for improving gait in Charcot-Marie-Tooth disease.OBJECTIVES:Investigate the effect of sensorimotor orthoses on in-shoe and lower limb biomechanics in adults with Charcot-Marie-Tooth disease.STUDY DESIGN:Randomised, repeated-measures, exploratory study.METHODS:Eight males and two females with Charcot-Marie-Tooth disease aged 31-68 years fitted with pedorthic shoes and custom-made sensorimotor orthoses were randomly tested at baseline and after 4 weeks of adaptation. In-shoe three-dimensional multi-segment foot and lower limb kinematics and kinetics were collected as were plantar pressures, electromyography and self-reported comfort, stability, cushioning and preference.RESULTS:Compared to the shoe only condition, sensorimotor orthoses increased midfoot eversion and plantarflexion, increased ankle eversion and produced small but significant changes at the knee and hip indicating increased internal rotation. The orthoses increased medial ground reaction forces and increased pressure at the heel, midfoot and toes. There were minimal effects on electromyography. The sensorimotor orthoses were rated higher for comfort, cushioning, stability and preference.CONCLUSION:Sensorimotor orthoses produced changes in kinematic, kinetic and pressure variables in adults with Charcot-Marie-Tooth disease and were regarded as more comfortable, cushioned and stable during walking.CLINICAL RELEVANCE:In this study, the walking ability of patients with Charcot-Marie-Tooth disease improved with the use of foot orthoses designed according to the sensorimotor paradigm. However, the mechanism of action appears to be primarily mechanical in origin. Randomised controlled trials are necessary to evaluate the long-term patient-reported outcomes of sensorimotor orthoses.
Background Charcot-Marie-Tooth disease (CMT) is the most common hereditary peripheral neuropathy, with an incidence of 1 in 2,500 [1]. CMT is characterised by the progressive weakening of the distal muscles and sensory loss of the limbs, particularly around the foot and ankle resulting in balance, walking impairments, cavus foot deformity and lateral instability [2,3]. Clinical anecdotes suggest foot orthoses designed on the ‘sensorimotor’ paradigm proposed by Lothar Jahrling are beneficial at improving lateral stability during gait in patients with CMT. The purpose of this study was to investigate the effect of sensorimotor orthoses on frontal plane ankle motion in people with CMT.
Introduction: Children's shoes considerably alter midfoot and ankle function during propulsion. However the effect of shoes on children's performance and the mechanisms behind potential alterations to performance are poorly understood. The purpose of this study was to investigate the dynamic midfoot and ankle mechanisms of vertical jump performance of children while barefoot and wearing shoes.
Shoes considerably alter the walking and running biomechanics of children (Wegener et al. 2011). However few studies have investigated the effect of shoes on children's physical performance. Tazuke...
Methods Twenty children performed five walking and running trials at a self-selected velocity while barefoot and wearing a common sports shoe. Footwear testing order was randomised. A 14 camera motion analysis system was used to calculate retro-reflective marker trajectories at 200Hz. Markers were attached to the leg and to the foot through holes in the shoe to measure three-dimensional motion of the midfoot and ankle. Ground reaction force data were recorded at 1,000Hz. Data were normalised to the stance phase and analysed from 60% to 100%.
Although it could be perceived that there is extensive research on the impact attenuation characteristics of shoes, the approach and findings of researchers in this area are varied. This review aimed to clarify the effect of shoes on impact attenuation to the foot and lower leg and was limited to those studies that compared the shoe condition(s) with barefoot. A systematic search of the literature yielded 26 studies that investigated vertical ground reaction force, axial tibial acceleration, loading rate and local plantar pressures. Meta-analyses of the effect of shoes on each variable during walking and running were performed using the inverse variance technique. Variables were collected at their peak or at the impact transient, but when grouped together as previous comparisons have done, shoes reduced local plantar pressure and tibial acceleration, but did not affect vertical force or loading rate for walking. During running, shoes reduced tibial acceleration but did not affect loading rate or vertical force. Further meta-analyses were performed, isolating shoe type and when the measurements were collected. Athletic shoes reduced peak vertical force during walking, but increased vertical force at the impact transient and no change occurred for the other variables. During running, athletic shoes reduced loading rate but did not affect vertical force. The range of variables examined and variety of measurements used appears to be a reason for the discrepancies across the literature. The impact attenuating effect of shoes has potentially both adverse and beneficial effects depending on the variable and activity under investigation.
In children the midfoot generates 35–48% of the peak power from the foot and ankle during propulsion of walking (MacWilliams et al. 2003, Bruening et al. 2012, Dixon et al. 2012). Although it has b...
Methods Nine boys and 10 girls (mean age 10 years (SD1.4)) performed four activities barefoot and wearing sports shoes (Kanbarra, Asics Oceania Pty Ltd.) in a randomised order. To allow for a gradual warm up, activities were undertaken in a predetermined order of: 2x20sec single leg balance eyes open; 2 x20sec single leg balance eyes closed; 2x standing long jump; timed running agility (4x10m). These tasks were undertaken as previously described in the literature [2,3]. The balance tasks were undertaken on concrete surface, while the standing long jump and agility were undertaken on carpet. The better of two performances, except running agility in which only one attempt was undertaken, were selected for analysis. Significance was assessed with the Wilcoxon Signed rank test for non-parametric data and a paired samples t-test for parametric data.
Background The aim of the workshop is to explore the effects of footwear design on lower limb motion and discuss research findings relevant to the clinic and physical activity. Delegates will be actively involved in a motion capture process where important lower limb joint stress variables will be displayed in real time. The University of Sydney researchers will raise footwear issues from a range of areas such as children physical activity, adult walking and running, specific footwear such as thongs (flip-flops), dance and experimental methodology. During or on completion of this workshop, participants will be able to: • Critically analyse footwear characteristics that are likely to influence lower limb function during physical activity. • Experience the use of state of the art technology to analyse lower limb mechanics. • Discuss the models and methods used to build knowledge about the effect of footwear on lower limb mechanics. • Recount clinical and research outcomes for the effect of footwear on lower limb biomechanics during physical activity. • Apply biomechanical principles to the effective choice of footwear for a range of physical activities.
Materials and methods Twenty children (mean age 9 years (SD2.3)) performed five running trials at a self-selected velocity barefoot and wearing school shoes (Daytona, Clarks) in a random order. A 14 camera 200Hz motion analysis system (EVaRT5.0, MAC) was used to calculate marker trajectories. Markers were attached to the right leg and a cluster wand was attached to the calcaneus through a window in the shoe. A standing reference trial was used to embed segment axes and then calculate ankle joint complex motion. Force plate data were collected at 1000Hz (KistlerTM). Data were normalised to the stance phase and sub-phases partitioned from the anterior/posterior force data as: loading (initial-contact – maximumnegative force); mid-stance (maximum-negative force – zero) and propulsion (positive force – toe-off).
BACKGROUND:The effect of footwear on the gait of children is poorly understood. This systematic review synthesises the evidence of the biomechanical effects of shoes on children during walking and running. METHODS:Study inclusion criteria were: barefoot and shod conditions; healthy children aged ≤ 16 years; sample size of n > 1. Novelty footwear was excluded. Studies were located by online database-searching, hand-searching and contact with experts. Two authors selected studies and assessed study methodology using the Quality Index. Meta-analysis of continuous variables for homogeneous studies was undertaken using the inverse variance approach. Significance level was set at P < 0.05. Heterogeneity was measured by I2. Where I2 > 25%, a random-effects model analysis was used and where I2 < 25%, a fixed-effects model was used. RESULTS:Eleven studies were included. Sample size ranged from 4-898. Median Quality Index was 20/32 (range 11-27). Five studies randomised shoe order, six studies standardised footwear. Shod walking increased: velocity, step length, step time, base of support, double-support time, stance time, time to toe-off, sagittal tibia-rearfoot range of motion (ROM), sagittal tibia-foot ROM, ankle max-plantarflexion, Ankle ROM, foot lift to max-plantarflexion, 'subtalar' rotation ROM, knee sagittal ROM and tibialis anterior activity. Shod walking decreased: cadence, single-support time, ankle max-dorsiflexion, ankle at foot-lift, hallux ROM, arch length change, foot torsion, forefoot supination, forefoot width and midfoot ROM in all planes. Shod running decreased: long axis maximum tibial-acceleration, shock-wave transmission as a ratio of maximum tibial-acceleration, ankle plantarflexion at foot strike, knee angular velocity and tibial swing velocity. No variables increased during shod running. CONCLUSIONS:Shoes affect the gait of children. With shoes, children walk faster by taking longer steps with greater ankle and knee motion and increased tibialis anterior activity. Shoes reduce foot motion and increase the support phases of the gait cycle. During running, shoes reduce swing phase leg speed, attenuate some shock and encourage a rearfoot strike pattern. The long-term effect of these changes on growth and development are currently unknown. The impact of footwear on gait should be considered when assessing the paediatric patient and evaluating the effect of shoe or in-shoe interventions.
navicular, 1 st and 5 th metatarsal heads and hallux. Rearfoot motion was measured with a wand marker cluster through a window in the shoe. A standing reference trial was used to embed segment axes and thence to calculate motion of the distal segment relative to the proximal segment. Data were normalised to the stance phase which was sub-divided from the anterior/posterior force data as: contact period (initial contact - maximum negative force); midstance (maximum negative force zero) and propulsion (positive force - toe-off). Results Five boys and seven girls participated in the study (mean age 9 years, range 5-13 years). During the contact period shoes decreased midfoot range of motion (ROM) in the frontal plane from 3.4° to 1.7° (p=0.002) and in the transverse plane from 22.0° to 11.6° (p<0.001). No significant difference in ROM occurred during midstance at either the rearfoot or midfoot. During propulsion shoes reduced rearfoot ROM in the frontal plane from 12.0° to 9.6° (p=0.026) and midfoot ROM in the sagittal plan from 19.6° to 10.8° (p<0.001) and in the transverse plan from 10.1° to 4.3° (p<0.001). Conclusions Traditional school shoes restrict children’s foot motion during walking particularly at the midfoot during the contact period and propulsion phases of gait. The medium and long-term impacts of these changes are the focus of further research. The impact of school shoes on foot motion should be considered when assessing the paediatric patient and evaluating the effect of shoe or in-shoe interventions.