Caleb Wegener

Effect of Neutral-Cushioned Running Shoes on Plantar Pressure Loading and Comfort in Athletes With Cavus Feet A Crossover Randomized Controlled Trial

Background High injury rates observed in athletes with cavus feet are thought to be associated with elevated plantar pressure loading. Neutral-cushioned running shoes are often recommended to manage and prevent such injuries. Purpose To investigate in-shoe plantar pressure loading and comfort during running in 2 popular neutral-cushioned running shoes recommended for athletes with cavus feet. Study Design Controlled laboratory study. Methods Plantar pressures were collected using the in-shoe Novel Pedar-X system during overground running in 22 athletes with cavus feet in 2 neutral-cushioned running shoes (Asics Nimbus 6 and Brooks Glycerin 3) and a control condition (Dunlop Volley). Comfort was measured using a validated visual analog scale. Results Compared with the control, both neutral-cushioned running shoes significantly reduced peak pressure and pressure-time integrals by 17% to 33% (P < .001). The Brooks Glycerin most effectively reduced pressure beneath the whole foot and forefoot (P < .01), and the Asics Nimbus most effectively reduced rearfoot pressure (P < .01). Both neutral-cushioned running shoes reduced force at the forefoot by 6% and increased it at the midfoot by 12% to 17% (P < .05). Contact time and area increased in both neutral-cushioned running shoes (P < .01). The Asics Nimbus was the most comfortable, although both neutral-cushioned running shoes were significantly more comfortable than the control (P < .001). Conclusion Two popular types of neutral-cushioned running shoes were effective at reducing plantar pressures in athletes with cavus feet. Clinical Relevance Regional differences in pressure reduction suggest neutral-cushioned running shoe recommendation should shift from being categorical in nature to being based on location of injury or elevated plantar pressure.

Impact attenuation during weight bearing activities in barefoot vs. shod conditions: A systematic review

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.

Children’s rearfoot and midfoot motion while walking in school shoes

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.

In-shoe multi-segment foot kinematics of children during the propulsive phase of walking and running

Certain styles of childrens 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 childrens 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, childrens sports shoes have a splinting effect on 1st MTPJ and midfoot motion which is partially compensated by an increase in ankle plantarflexion during running.

Biomechanical effects of sensorimotor orthoses in adults with Charcot-Marie-Tooth disease.

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.

Correlates of Perceived Ankle Instability in Healthy Individuals Aged 8 to 101 Years

OBJECTIVES To provide reference data for the Cumberland Ankle Instability Tool (CAIT) and to investigate the prevalence and correlates of perceived ankle instability in a large healthy population. DESIGN Cross-sectional observational study. SETTING University laboratory. PARTICIPANTS Self-reported healthy individuals (N=900; age range, 8-101y, stratified by age and sex) from the 1000 Norms Project. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Participants completed the CAIT (age range, 18-101y) or CAIT-Youth (age range, 8-17y). Sociodemographic factors, anthropometric measures, hypermobility, foot alignment, toes strength, lower limb alignment, and ankle strength and range of motion were analyzed. RESULTS Of the 900 individuals aged 8 to 101 years, 203 (23%) had bilateral and 73 (8%) had unilateral perceived ankle instability. The odds of bilateral ankle instability were 2.6 (95% confidence interval [CI], 1.7-3.8; P<.001) times higher for female individuals, decreased by 2% (95% CI, 1%-3%; P=.001) for each year of increasing age, increased by 3% (95% CI, 0%-6%; P=.041) for each degree of ankle dorsiflexion tightness, and increased by 4% (95% CI, 2%-6%, P<.001) for each centimeter of increased waist circumference. CONCLUSIONS Perceived ankle instability was common, with almost a quarter of the sample reporting bilateral instability. Female sex, younger age, increased abdominal adiposity, and decreased ankle dorsiflexion range of motion were independently associated with perceived ankle instability.

Effect of sensorimotor orthoses on rearfoot motion in patients with Charcot-Marie-Tooth disease: a pilot study

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.

Power generation of the midfoot in children wearing sports shoes

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%.

Effect of sports shoes on children's vertical jump performance and midfoot and ankle kinetics

between the young and old cohorts, suggests that the risk of falling is increased by approximately 45% in healthy older people relative to their younger counterparts. There is evidence to suggest that the toe flexor muscles can respond to training, not only through traditional resistance exercises, but also through specialised footwear (Potthast et al. 2005, Munro et al. 2011). Therefore, further efforts into the research and design of functional footwear that can be targeted at restoring foot function in the growing older population should be made a priority. References

Effect of sports shoes on midfoot power generation in children while walking and running

The search for a dominant object with further schematisation of its interconnections with lower category objects shows that the shoe last is dominating in the footwear CAD structure (Figure 1). The cast form and dimensions are dictated by a conditional average foot (CAF) which is the result of statistical evaluation for every sex-age population group. To obtain a shell of the cast surface, which could be later used to form a shell of the last surface, one is to take into consideration certain pre-defined conditions: possible transformation of the solid foot during walking, running, etc. Then the so-called virtual average foot (VAF) is consequently shaped from CAF using its five basic positions (footholds for both feet and taking into account other foot positions). When moving from the VAF to the last surface, one should take into consideration change of the foot shape in motion, and following possible painful sensations in the human’s vital functions, and the properties of the materials set chosen for the upper, functions and usage of the ready-made product, etc. The influence of those factors on shaping the last surface shell is described analytically with the help of appropriate coefficients (Zamarashkin and Zamarashkin 2002). The sufficiency of moving from a VAF cast to the last surface depends on reliable estimation of properties describing the force interaction of the foot and the footwear. Analytical estimates connecting foot pressure, its geometry, physical and mechanical properties of the upper materials set, foot anatomy and physiology is developed. With them, stages of making a last model and further test wearing may be omitted.