Soft-tissue vibration and damping response to footwear changes across a wide range of anthropometrics in running

Different factors were shown to alter the vibration characteristics of soft-tissue compartments during running. Changing pre-heel strike muscle activation or changing footwear conditions represents two possibilities to influence the vibration response via frequency shift or altered damping. Associated with the study of muscle pre-tuning is the difficulty in quantifying clean experimental data for the acceleration of soft-tissue compartments and muscle activities in heterogeneous populations. The purpose of this study was to determine the vibration and pre-tuning response to footwear across a wide range of participants during running and establish and describe groups formed according to the damping coefficient. 32 subjects were used for further analysis. The subjects ran at a self-selected speed (5 min) on a treadmill in two different shoes (soft & hard), while soft-tissue accelerations and muscle activation at the gastrocnemius medialis were quantified. Damping coefficients, total muscle intensity and dominant vibration frequencies were determined. Anthropometrics and skinfold measurements of the lower limbs were obtained. According to the damping coefficient response to the footwear intervention, three groups were formed, with most runners (n = 20) showing less damping in the hard shoe. Total muscle intensity, anthropometrics, and dominant vibration frequency across footwear were not different for these three groups. Most runners (84.4%) used the strategy of adjusting the damping coefficients significantly when switching footwear. Despite damping being the preferred adjustment to changes in footwear, muscle pre-tuning might not be the only mechanism to influence damping as previously suggested. Future studies should focus on the subject-specific composition of soft-tissue compartments to elucidate their contribution to vibrations.

Footwear used by older people and a history of hyperkeratotic lesions on the foot: A prospective observational study

Inadequate footwear, painful and hyperkeratotic lesions (HL) are an extremely common problems amongst older people. Such problems increase the risk of falls, hamper mobility, reduction of quality of life, dignity, and ability to remain independent. The etiology of painful and feet conditions is poorly understood.To discover footwear preferences of older people, pain tolerance may favor presence of HL for the use of inadequate footwear in old age.A sample of 100 participants with a mean age of 74.90 ± 7.01 years attended an outpatient clinic where self-reported demographic data, frequency with which they checked their feet were recorded and measurements were taken of foot sensitivity. Additionally, all participants' shoes were allocated into optimal, adequate, and dangerous categories based on design, structural and safety features, and materials.Only 12% of the sample population checked their feet every day, 37% revealed symptoms of neuropathy, 14% used optimal shoes, and 61% presented HL. In a bivariate analysis, no significant differences were observed.HL are associated with inadequate footwear, loss of sensitivity, and low frequency of foot health checks.

Injuries And Footwear (Part 2): Minimalist Running Shoes

This article defines minimalist running shoes and examines physiological, biomechanical, and injury rate differences when running in conventional versus minimalist running shoes. A minimalist shoe is one that provides "minimal interference with the natural movement of the foot, because of its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices." Most studies indicate that running in minimalist shoes results in a lower physiological energy cost than running in conventional shoes, likely because of the lower weight of the minimalist shoe. Most individuals running in conventional shoes impact the ground heel first (rearfoot strike pattern), whereas most people running in minimalist shoes tend to strike with the front of the foot (forefoot strike pattern). The rate at which force is developed on ground impact (i.e., the loading rate) is generally higher when running in conventional versus minimalist shoes. Findings from studies that have looked at associations between injuries and foot strike patterns or injuries and loading rates are conflicting, so it is not clear if these factors influence injury rates; more research is needed. Better-designed prospective studies indicate that bone stress injuries and the overall injury incidence are higher in minimalist shoes during the early weeks (10-12 weeks) of transition to this type of footwear. Longer-term studies are needed to define injury rates once runners are fully transitioned to minimalist shoes. At least one longer-term minimalist-shoe investigation is ongoing and, hopefully, will be published soon.

The long-term effect of minimalist shoes on running performance and injury: design of a randomised controlled trial

INTRODUCTION

The outcome of the effects of transitioning to minimalist running shoes is a topic of interest for runners and scientists. However, few studies have investigated the longer term effects of running in minimalist shoes. The purpose of this randomised controlled trial (RCT) is to investigate the effects of a 26 week transition to minimalist shoes on running performance and injury risk in trained runners unaccustomed to minimalist footwear.

METHODS AND ANALYSIS

A randomised parallel intervention design will be used. Seventy-six trained male runners will be recruited. To be eligible, runners must be aged 18-40 years, run with a habitual rearfoot footfall pattern, train with conventional shoes and have no prior experience with minimalist shoes. Runners will complete a standardised transition to either minimalist or control shoes and undergo assessments at baseline, 6 and 26 weeks. 5 km time-trial performance (5TT), running economy, running biomechanics, triceps surae muscle strength and lower limb bone mineral density will be assessed at each time point. Pain and injury will be recorded weekly. Training will be standardised during the first 6 weeks. Primary statistical analysis will compare 5TT between shoe groups at the 6-week time point and injury incidence across the entire 26-week study period.

ETHICS AND DISSEMINATION

This RCT has been approved by the Human Research Ethics Committee of the University of South Australia. Participants will be required to provide their written informed consent prior to participation in the study. Study findings will be disseminated in the form of journal publications and conference presentations after completion of planned data analysis.

TRIAL REGISTRATION NUMBER

This RCT has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN12613000642785).

Footwear and Foam Surface Alter Gait Initiation of Typical Subjects

Gait initiation is the task commonly used to investigate the anticipatory postural adjustments necessary to begin a new gait cycle from the standing position. In this study, we analyzed whether and how foot-floor interface characteristics influence the gait initiation process. For this purpose, 25 undergraduate students were evaluated while performing a gait initiation task in three experimental conditions: barefoot on a hard surface (barefoot condition), barefoot on a soft surface (foam condition), and shod on a hard surface (shod condition). Two force plates were used to acquire ground reaction forces and moments for each foot separately. A statistical parametric mapping (SPM) analysis was performed in COP time series. We compared the anterior-posterior (AP) and medial-lateral (ML) resultant center of pressure (COP) paths and average velocities, the force peaks under the right and left foot, and the COP integral x force impulse for three different phases: the anticipatory postural adjustment (APA) phase (Phase 1), the swing-foot unloading phase (Phase 2), and the support-foot unloading phase (Phase 3). In Phase 1, significantly smaller ML COP paths and velocities were found for the shod condition compared to the barefoot and foam conditions. Significantly smaller ML COP paths were also found in Phase 2 for the shod condition compared to the barefoot and foam conditions. In Phase 3, increased AP COP velocities were found for the shod condition compared to the barefoot and foam conditions. SPM analysis revealed significant differences for vector COP time series in the shod condition compared to the barefoot and foam conditions. The foam condition limited the impulse-generating capacity of COP shift and produced smaller ML force peaks, resulting in limitations to body-weight transfer from the swing to the support foot. The results suggest that footwear and a soft surface affect COP and impose certain features of gait initiation, especially in the ML direction of Phase 1.

Diverse expected gradient active learning for relative attributes

The use of relative attributes for semantic understanding of images and videos is a promising way to improve communication between humans and machines. However, it is extremely labor- and time-consuming to define multiple attributes for each instance in large amount of data. One option is to incorporate active learning, so that the informative samples can be actively discovered and then labeled. However, most existing active-learning methods select samples one at a time (serial mode), and may therefore lose efficiency when learning multiple attributes. In this paper, we propose a batch-mode active-learning method, called diverse expected gradient active learning. This method integrates an informativeness analysis and a diversity analysis to form a diverse batch of queries. Specifically, the informativeness analysis employs the expected pairwise gradient length as a measure of informativeness, while the diversity analysis forces a constraint on the proposed diverse gradient angle. Since simultaneous optimization of these two parts is intractable, we utilize a two-step procedure to obtain the diverse batch of queries. A heuristic method is also introduced to suppress imbalanced multiclass distributions. Empirical evaluations of three different databases demonstrate the effectiveness and efficiency of the proposed approach.

Effects of barefoot and barefoot inspired footwear on knee and ankle loading during running

BACKGROUND

Recreational runners frequently suffer from chronic pathologies. The knee and ankle have been highlighted as common injury sites. Barefoot and barefoot inspired footwear have been cited as treatment modalities for running injuries as opposed to more conventional running shoes. This investigation examined knee and ankle loading in barefoot and barefoot inspired footwear in relation to conventional running shoes.

METHOD

Thirty recreational male runners underwent 3D running analysis at 4.0m·s(-1). Joint moments, patellofemoral contact force and pressure and Achilles tendon forces were compared between footwear.

FINDINGS

At the knee the results show that barefoot and barefoot inspired footwear were associated with significant reductions in patellofemoral kinetic parameters. The ankle kinetics indicate that barefoot and barefoot inspired footwear were associated with significant increases in Achilles tendon force compared to conventional shoes.

INTERPRETATION

Barefoot and barefoot inspired footwear may serve to reduce the incidence of knee injuries in runners although corresponding increases in Achilles tendon loading may induce an injury risk at this tendon.

Foot motion in children shoes: a comparison of barefoot walking with shod walking in conventional and flexible shoes

The increased prevalence for flatfoot and hallux valgus in modern societies may be the consequence of inadequate footwear in childhood. Based on the assumption that barefoot walking represents the best condition for the development of a healthy foot the objective of this study was to monitor the influence of commercial footwear on children's foot motion during walking. Furthermore, an attempt was made to reduce this influence by changing the physical properties of standard footwear. Children's barefoot motion pattern was monitored by a marker-based optical 3D-tracking method using a multi-segment foot model. In the study's first stage, barefoot walking was compared to walking with a commercial product. In the second stage it was compared to both, the pattern with the commercial product and with the shoe modified on the basis of the findings of the first stage of the study. Eighteen children (8.2+/-0.7 years old) with no foot deformity and with the same shoe size were recruited for this study. It was found that tibio-talar ROM increased in the commercial shoe (26.6 degrees ) compared to the barefoot condition (22.5 degrees , p=0.001) whereas the medial arch changes for push-off were diminished since the variation in arch length was reduced from 9.9% (barefoot) to 5.9% (shoe, p<0.001). Further, ROM in foot torsion along the long foot axis was reduced from 9.8 degrees (bare) to 4.7 degrees (shoe, p<0.001). These parameters could be improved with more flexible footwear. The present study shows that slimmer and more flexible children's shoes do not change foot motion as much as conventional shoes and therefore should be recommended not only for children in this age but for healthy children in general.

Effects of insoles and additional shock absorption foam on the cushioning properties of sport shoes

The purpose of this study was to investigate the effects of insoles and additional shock absorption foam on the cushioning properties of various sport shoes with an impact testing method. Three commercial sport shoes were used in this study, and shock absorption foam (TPE5020; Vers Tech Science Co. Ltd., Taiwan) with 2-mm thickness was placed below the insole in the heel region for each shoe. Eight total impacts with potential energy ranged from 1.82 to 6.08 J were performed onto the heel region of the shoe. The order of testing conditions was first without insole, then with insole, and finally interposing the shock absorption foam for each shoe. Peak deceleration of the striker was measured with an accelerometer attached to the striker during impact. The results of this study seemed to show that the insole or additional shock absorption foam could perform its shock absorption effect well for the shoes with limited midsole cushioning. Further, our findings showed that insoles absorbed more, even up to 24-32% of impact energy under low impact energy. It seemed to indicate that insoles play a more important role in cushioning properties of sport shoes under a low impact energy condition.

[Grading of the functional sport shoe parameter "cushioning" and "forefoot flexibility" on running shoes]

On nearly every running event a heterogeneous structure of participants regarding body height and body weight can be observed. This study should figure out whether the running shoe manufacturers will consider this anthropometric variability. Moreover it should be investigated the runners needs based on different anthropometrics regarding preferred cushioning and forefoot flexibility properties. In order to check whether the running shoe manufacturers will apply a grading pattern, a dynamic material study with conventional running shoes in different sizes was conducted. In a second step a field study in Middle Europe and North America with 244 female and 227 male runners was organized. Every subject had to run and evaluate 7 different shoe modifications. Based on the material study it is to state, that the running shoe manufacturers currently do not consider a systematic grading of cushioning and forefoot flexibility properties. In contrast to this, the field study reveals the necessity to grade these properties. A shoe size dependent and a geographic grading concept are suggested. It is supposed, that the application of these grading concepts do not only provide a comfort improvement, but they also contribute to a reduction of joint loads of the lower extremities and consequently to a prevention of overuse injuries.

Automated processing of shoeprint images based on the Fourier transform for use in forensic science

The development of a system for automatically sorting a database of shoeprint images based on the outsole pattern in response to a reference shoeprint image is presented. The database images are sorted so that those from the same pattern group as the reference shoeprint are likely to be at the start of the list. A database of 476 complete shoeprint images belonging to 140 pattern groups was established with each group containing two or more examples. A panel of human observers performed the grouping of the images into pattern categories. Tests of the system using the database showed that the first-ranked database image belongs to the same pattern category as the reference image 65 percent of the time and that a correct match appears within the first 5 percent of the sorted images 87 percent of the time. The system has translational and rotational invariance so that the spatial positioning of the reference shoeprint images does not have to correspond with the spatial positioning of the shoeprint images of the database. The performance of the system for matching partial-prints was also determined.

[Comprehensively analysis the correlation between the height of a person and the length of his/her footprint]

OBJECTIVE

Comprehensively analysis the correlation and the law of variation between the height of a person and the length of his/her footprint.

METHODS

Collecting footprint samples of those people of different age and sex from different area all of our country, and adopt the regressive analysis method to study these samples.

RESULTS

A sum of useful data and regressive equation were obtained.

CONCLUSION

The correlation between the height of a person and the length of his/her footprint is obviously, the approximate height of a person can be reckoned according to thelength of his/her footprints.

The Therapeutic Shoe Bill: Medicare coverage for prescription footwear for diabetic patients

This article describes the extent of coverage and the process of obtaining Medicare coverage for prescription footwear for patients with diabetes and reflects policies in effect as of April 1, 2004.

Dimensional differences for evaluating the quality of footwear fit

Very few standards exist for fitting products to people. Footwear is a noteworthy example. This study is an attempt to evaluate the quality of footwear fit using two-dimensional foot outlines. Twenty Hong Kong Chinese students participated in an experiment that involved three pairs of dress shoes and one pair of athletic shoes. The participants' feet were scanned using a commercial laser scanner, and each participant wore and rated the fit of each region of each shoe. The shoe lasts were also scanned and were used to match the foot scans with the last scans. The ANOVA showed significant (p < 0.05) differences among the four pairs of shoes for the overall, fore-foot and rear-foot fit ratings. There were no significant differences among shoes for mid-foot fit rating. These perceived differences were further analysed after matching the 2D outlines of both last and feet. The point-wise dimensional difference between foot and shoe outlines were computed and analysed after normalizing with foot perimeter. The dimensional difference (DD) plots along the foot perimeter showed that fore-foot fit was strongly correlated (R(2) > 0.8) with two of the minimums in the DD-plot while mid-foot fit was strongly correlated (R(2) > 0.9) with the dimensional difference around the arch region and a point on the lateral side of the foot. The DD-plots allow the designer to determine the critical locations that may affect footwear fit in addition to quantifying the nature of misfit so that design changes to shape and material may be possible.

[Chronology of horseshoes found in Switzerland]

The horse was domesticated by a people in Central Asia. However, it is not known where and who invented horse shoeing, an invention that increased the possibilities for using horses. The word "horseshoe" was first mentioned in a document from 826 p.c. Up to now an archaeologist couldn't date an excavated horseshoe. I succeeded now to establish a chronology for horseshoes found in Switzerland. The first realisation is that in the course of more than thousand years of horse shoeing history three basic forms followed each other. Moreover, the existing horseshoes can be allocated to periodical types, each in use for approximately a quarter of a century.

Forensic comparison of soils by bacterial community DNA profiling

This preliminary investigation has shown that a soil microbial community DNA profile can be obtained from the small sample of soil recovered from the sole of a shoe, and from soil stains on clothing. We have also shown that these profiles are representative of the site of collection and therefore could potentially be used as associative evidence to prove a link between suspects and crime scenes. Soil community profiles were obtained using the T-RFLP fingerprinting method that uses fluorescent primer technology and semi-automated analysis techniques similar to those used in human DNA profiling in forensic laboratories.

A comparison of three horseshoeing styles on the kinetics of breakover in sound horses

A variety of horseshoe designs are believed to 'ease' breakover, or the unloading of the foot once the heels leave the ground. In this study, conventional toe-clip shoes, quarter-clip shoes, fitted to the white line at the toe, and Natural Balance horseshoes were fitted to the front feet of 9 sound Irish Draught-cross type horses. Forceplate and video motion analyses were undertaken during trot locomotion to determine the moment arm of the ground reaction force on the distal interphalangeal (DIP) joint, the peak DIP joint moment and the peak compressive force on the navicular bone. DIP joint moment arm during breakover was reduced with both Natural Balance (mean +/- s.d. 77 +/- 7 mm) and quarter-clip shoes (78 +/- 9 mm) compared to the toe-clip shoes (86 +/- 6 mm) (P<0.01). Peak DIP joint moment was not significantly different (175 +/- 37,171 +/- 38 and 175 +/- 31 Nmm/kg, in Natural Balance, quarter-clip and toe-clip shoes, respectively) and neither was peak force on the navicular bone (5.52 +/- 1.52, 5.79 +/- 1.53 and 6.14 +/- 1.47 N/kg, respectively). Breakover duration (heel off to toe off) was not significantly reduced by the Natural Balance shoes (39 +/- 6 ms) or the quarter-clip shoes (40 +/- 6 ms) compared to toe-clip shoes (42 +/- 9 ms). This study has demonstrated that the use of Natural Balance shoes reduces the moment arm of the ground reaction force (GRF) during breakover but does not reduce the peak DIP joint moment or the force on the navicular bone.

Shoe design for prevention of injuries in sport climbing

Foot injuries and deformations are more frequent at higher levels of sport climbing. These are accepted as unavoidable because it is assumed that, for optimal performance, a prerequisite is the wearing of a shoe, which is too tight and has an unnatural shape. Based on a biomechanical analysis, we came up with a different approach to shoe design. By using regional thinning of the sole, easy flexion and extension of the toes is made possible. The form of the shoe conforms to the natural form of the foot, the shoe closure provides a close fit for feet with width differences of up to 20 mm and a shoe-sizing system was developed. After testing prototypes, we conclude that the new shoe design can contribute to the prevention of foot injuries and deformations in sport climbing.

[Electronic plantar pressure measurements in different types of moutaineering boots]

Specific footwear has been developed for different, partly newly developed mountain sports. This footwear has very different basic characteristics. This experimental study is dealing with the dynamic parameters of electronic plantar pressure measurements in normal walking using different mountain sport shoes designed for a special purpose in mountaineering. These mountain shoes included a hiking shoe, a trekking shoe and a high-alpine shoe which can take crampons. The electronic plantar pressure measurements were done with the Parotec system of the company Paromed with insoles with hydrocell-sensors. The data obtained during the study were proceeded through a variant analysis. There were no significant differences for impulse and contact time, nevertheless concerning maximal pressure there were significant differences between walking barefoot and walking with the hiking and high-alpine shoe. Even when walking in different mountain shoes the feet conserve their own characteristics and their walking style. The different mountain shoes did not alter most of the measured plantar parameters significantly comparing barefoot walking to walking with the different mountain shoes or comparing walking in the different mountain shoes.

Force patterns of heel strike and toe off on different heel heights in normal walking

This study investigated the changes of force patterns of the heel strike and toe off phases at different heel heights during normal walking. Ten healthy female college students wore running shoes, flat leather shoes and high heeled shoes while walking on a Kistler force platform at their self-comfortable paces. It was found that the high heeled shoes and the leather shoes generated significantly greater vertical impact forces and anterior-posterior forces in the toe off phase than those in the heel strike phase. Accumulated impulses did not show significant increase while the heel heights increased and total support time while wearing the high heeled shoes was significantly longer than while wearing the running shoes.

The effect of roughness, floor polish, water, oil and ice on underfoot friction: current safety footwear solings are less slip resistant than microcellular polyurethane

Research over a period of about 18 years has shown that a microcellular polyurethane known as AP66033 is the most slip-resistant safety footwear soling material on oily and wet surfaces. In recent years it has been replaced in commercially available footwear by a dual density polyurethane (DDP) which has a dense outer layer and a soft microcellular backing. This research programme has compared the slip resistance of AP66033 with DDP and some rubber solings. In addition, data were obtained on the effects of soling and floor roughness, and floor polish on slip resistance. Some data were also obtained for walking on ice. The coefficient of friction (CoF) of the solings was measured on 19 water wet surfaces in three conditions: (I) when the solings were new, (II) following abrasion to create maximum roughness and (III) after polishing. The CoF was measured on four oily surfaces after each of 11 abrasion or polishing treatments. The profound effects of the roughening of all soles and of floor roughness on the CoF were demonstrated for both wet and oily surfaces. The superior slip resistance of AP66033 was confirmed for oily and wet conditions; however, some rubbers not suitable for safety footwear achieved higher CoF values on wet floors. All of the floor polishes reduced the CoF of all floors when contaminated with water. The mean CoF of DDP solings was lower than the mean for AP66033 on wet and oily surfaces. No safety footwear soling provided adequate grip on dry ice and the CoF was reduced by water on the ice. A rubber used for rock climbing footwear was one of the most slip-resistant solings on wet surfaces in the laboratory but recorded the lowest CoF on ice. It is concluded that the incidence of occupational injuries caused by slipping could be reduced by the following: (A) returning to safety footwear soled with the microcellular polyurethane AP66033; (B) abrading all new and smooth footwear solings with a belt sanding machine coated with P100 grit; (C) avoiding the use of floor polish; (D) informing the general public about the poor slip resistance of ordinary footwear on ice and the lowering of slip resistance in cold weather.

The effect of surface roughness and contaminant on the dynamic friction of porcelain tile

Surface roughness affects friction, but it is not clear what surface roughness characteristics are better correlated with friction. The average of the maximum height above the mean line in each cut-off length (Rpm) and the arithmetical average of surface slope (deltaa) had the highest correlation with dynamic friction coefficient in a previous study. The previous study was expanded to two different footwear materials and four different contaminants on a porcelain tile in the current investigation. The results showed that dynamic friction decreased as the interface speed and glycerol content in the contaminant were increased due to the hydrodynamic lubrication effect. Deltaa had the highest correlation with friction for most of the test conditions with neolite. For Four S rubber, friction coefficient appeared to have the highest correlation with the parameters related to the surface void volume at 30% glycerol content, related to the surface slope at 70 and 85% glycerol contents, and related to the peak to valley distance at 99% glycerol content. A good indicator of surface slip resistance probably should consist of the surface parameters representing the surface slope, the surface void volume and the surface peak-to-valley distance with the coefficients determined by the system parameters.

Influence of foot, leg and shoe characteristics on subjective comfort

The purpose of this study was to determine the relationships between foot and leg characteristics, shoe characteristics, and the short-term subjective comfort of three different pairs of athletic shoes. Static measurements of foot dimension and leg angles were taken from eighteen subjects. Subjects rated the comfort of three different athletic shoes for standing, walking and running. The shoes were quantified by internal dimensions, hardness, flexibility and torsional stiffness. Average comfort ratings decreased from standing to walking to running. One shoe seemed suited for only a small group of subjects. In contrast, another shoe was generally comfortable for a large group. Skeletal alignment, specifically eversion angle, was related to comfort for one shoe. Therefore, fit of the shoe is not sufficient for comfort. Skeletal alignment, shoe torsional stiffness and cushioning seem to be mechanical variables which may be important for comfort.

Developments in orthotic deweighting technology

The ability to unload various aspects of the lower extremity has proven a useful orthotic treatment for a variety of pathologies. This article discusses and categorizes various orthotic techniques.

A statistical study of air bubbles on athletic shoesoles

Comparisons of a shoemark with a shoesole (and standards) sometimes lead to associations based on air bubbles (among other manufacturing or acquired characteristics). Today, the assessment of the evidential value of air bubbles coincidences relies largely upon the examiner's experience and/or follows sometimes a verification based on the examination of a small number of analogous pairs collected for the case at hand. Statistical data related to the occurrence and characteristics of air bubbles on shoesoles in an attempt to model the potential variability have been gathered. Seventy-one pairs of shoes with the same design, brand, model and size were obtained. Right and left soles were photographed. An image-processing algorithm was developed to allow the systematic acquisition of data such as: (1) the number of air bubbles on the sole and around given structural elements; (2) the measure of air bubbles characteristics such as their surface and position. These data allow a discussion of the assessment of the probability of finding on shoesoles (same design, brand, model and size) a certain number of air bubbles on a surface with the same positions and morphology.

Factors associated with ankle injuries. Preventive measures

A sense of foot position in humans is precise when barefoot, but is distorted by athletic footwear, which accounts for the high frequency of ankle sprains in shod athletes. It is unclear whether taping and rigid and semi-rigid devices protect against ankle sprains, as all of the studies suggesting this are flawed by inadequate controls. If these devices do protect the ankle, it is not through added support but rather through a partial correction of the deceased foot position awareness caused by footwear. Since taping and rigid and semi-rigid devices interfere with normal movement, there is concern that these might actually increase the frequency of injury at the ankle and/or at different locations. In this respect, taping is less of a concern because it interferes least with normal movement. The best solution for reducing ankle sprains in shod athletes is the use of more advanced footwear to retain maximal tactile sensitivity, thereby maintaining an awareness of foot position comparable to that of the barefoot state or perhaps even improving on it.

Therapeutic footwear: enhanced function in people with diabetes and transmetatarsal amputation

OBJECTIVE

Patients with diabetes mellitus (DM) and a transmetatarsal amputation (TMA) have considerable deficits in function compared with age-matched controls. The purpose of this study was to determine if therapeutic footwear could improve the functional mobility of patients with DM and TMA.

STUDY DESIGN

Repeated-measures design.

SETTING

Academic medical center.

PATIENTS

Thirty subjects (10 women, 20 men) with DM and a TMA, with a mean age of 61.7 +/- 4.0 yrs.

INTERVENTIONS

Six types of footwear evaluating the following components: length of shoe (full-length or short shoe), a rigid rocker-bottom sole, and an ankle-foot-orthosis.

OUTCOME MEASURES

Physical Performance Test (PPT), functional reach, and walking speed. Measurements in each footwear condition occurred after a 1-month adjustment period.

RESULTS

Patients wearing full-length custom-made shoes with a total-contact insert, a rigid rocker-bottom sole or a short shoe with a rigid rocker-bottom sole (with or without an ankle-foot-orthosis) had similar and significantly higher scores in the PPT and faster walking speed than when wearing regular shoes with a toe filler (p < .05). The short shoe and the ankle-foot-orthosis, however, generated many patient complaints about cosmesis and restriction at the ankle, respectively. There were no differences in any of the measures of functional reach.

CONCLUSION

Although there are individual exceptions, we recommend the full-length shoe, total-contact insert, and a rigid rocker-bottom sole for most patients with DM and a TMA.

The role of footwear in the prevention of foot lesions in patients with NIDDM. Conventional wisdom or evidence-based practice?

OBJECTIVE

To conduct a prospective evaluation of footwear characteristics as predictors of diabetic foot wounds.

RESEARCH DESIGN AND METHODS

A total of 352 patients with NIDDM enrolled in a randomized controlled trial aimed at preventing diabetic foot lesions in an academic general medicine practice were studied. Foot wounds (n = 63) were modeled univariately and multivariably using generalized estimating equations. The dependent variable was a wound classified as a 1.2 or greater according to the Seattle Wound Classification System, indicating at least a superficial or healing minor lesion with no functional interruption of the protective cutaneous barrier. Independent variables included detailed measures of style and material of patients' indoor and outdoor shoes, appropriate length and width, sock fibers, whether the patient had bought new shoes in the past 6 months, and if the patient had been recommended for special shoes. Modeling controlled for intervention status and physiological measures (baseline wound, monofilament abnormalities, and serum HDL level).

RESULTS

Initial screening (P < 0.20) suggested that a recommendation for special shoes, shoe length, and shoe width were indicative of wounds at follow-up (odds ratios [ORs] 2.19, 1.84, 1.86, respectively), while having bought shoes in the past 6 months was associated with no wound at follow-up (OR 0.60). The final multivariable model included only the recommendation for special shoes (OR 2.19; 95% CI 1.07-4.49).

CONCLUSIONS

Many variables commonly cited as protective measures in footwear for diabetic patients were not prospectively predictive when controlling for physiological risk factors. Rigorous analyses are needed to examine the many assumptions regarding footwear recommendations for diabetic patients.

A quantitative assessment of healing sandals and postoperative shoes in offloading the neuropathic diabetic foot

The purpose of this report is to compare plantar pressures between custom healing sandals and postoperative shoes using unmodified prescription shoe gear as a control. Using a repeat measures design, we recorded the plantar forefoot pressures of eight patients classified as diabetic foot category 1 (neuropathy, no significant deformity, no history of ulceration) with each ambulating in three devices: 1) unmodified prescription shoe gear, 2) postoperative shoe gear, and 3) a custom-fabricated healing sandal. Each subject served as his or her own control. The healing sandal significantly reduced plantar forefoot pressure in all areas of the forefoot except the fifth metatarsal head. The postoperative shoe did not significantly reduce pressure at any site in the forefoot when compared with unmodified prescription shoe gear.

Functional components of a sport shoe

The anatomy and construction of a sport shoe are so specific for its designated activity that injury may result from wearing an inappropriate shoe. It is important to understand the biomechanics of the foot as well as sport shoe construction to choose the right shoe for the right sport.

The effect of ambient temperature on the shoe-surface interface release coefficient

Previous studies of the shoe-surface interface correlated foot fixation with cleat length, configuration, and material composition as well as turf type and surface conditions. Our study examined the effect of temperature on the rotational torsion resistance of artificial turf football shoes. Five football shoe models, a flat-soled basketball-style turf shoe, a natural grass soccer-style shoe, and three multistudded turf shoes, were studied on dry Astro Turf at five temperatures (range, 52 degrees F to 110 degrees F). An assay device, a prosthetic foot mounted on a loaded stainless steel shaft, was used to determine the force necessary to release a shoe from the turf's surface. We used a torque wrench to apply a rotational force so that each shoe was pivoted counterclockwise through an arc of 60 degrees. Our results indicated that release coefficients differ within and among the shoe models at various turf temperatures. We also found that an increase in turf temperature, in combination with cleat characteristics, affects shoe-surface interface friction and potentially places the athlete's knee and ankle at risk of injury. Based on an established risk criterion, which correlated shoe-surface interface combinations in the laboratory with documented clinical occurrences, only the flat-soled basketball-style turf shoe could be designated "safe" or "probably safe" at all five temperatures.

Influence of shoes and heel strike on the loading of the hip joint

The forces and moments acting at the hip joint influence the long-term stability of the fixation of endoprostheses and the course of coxarthrosis. These loads may depend on the kind of footwear and the walking or running style. These factors were investigated in a patient with instrumented hip implants. He wore different sports shoes, normal leather shoes, hiking boots and clogs and walked barefoot with soft, normal and hard heel strikes. The loads were lowest while walking and jogging without shoes. All shoes increased the joint force and the bending moment at the implant slightly but the torsional moment rose by up to 50%. No relation was found between the different type of shoes and the load increase, only shoes with very hard soles were clearly disadvantageous. Soft heels, soles or insoles did not offer advantages. Gait stability seems to play the most important role in increasing the joint loading and should be the criterion for the choice of footwear. Smooth gait patterns with soft heel strikes are the only means to reduce joint loading during slow jogging.

An improved technique to enable 2-dimensional shoe sole impression evidence to be photographically recorded "to scale"

An improved technique to photographically record 2-Dimensional shoe sole impressions "to scale" is described. This technique was developed as a result of continual attacks in court in relation to the question of precise SCALE. Staff at our laboratory are routinely required to examine shoe sole impressions evidence that has been collected by our Scenes of Crime Officers. The Scenes of Crime Officers have been instructed in the appropriate photographic techniques which should be used to record 2-Dimensional shoe sole impressions, however, for one reason or another, including inexperience, this technique is not rigidly adhered to. We have seventy-five (75) Scenes of Crime Officers throughout Queensland, and nearly all of the shoe sole interpretation work is done in the Brisbane Headquarters. It is the case that the Scenes of Crime Officers record the scene and other photographers record the Test Impression. There are three problems that affect the quality of the scale photographs submitted. 1. The camera is not directly over the center of the subject. 2. The camera is not exactly parallel to the subject. 3. The designs of the camera lens. These problems are highlighted when barristers compare the scale photos of the test impressions made in the laboratory, with the scale photos of the scene impressions. Barristers actually measure the distance between features and usually a discrepancy (albeit slight) is found. The GRID allows us to demonstrate to Lay persons and Lawyers the interrelationship of identification features, by reference to a particular GRID.

'Grippers' shoes: can they be reused?

'Grippers' footwear has been recommended for patients with painful or bandaged feet. In order to reduce costs, reuse between patients may be considered. The manufacturer's proposed washing instructions were evaluated. Thermal disinfection was not achieved with the 40 degrees C wash cycle recommended. Higher temperatures resulted in shrinkage and deformation of the shoes. We recommend that these shoes are not reused or that alternative methods of disinfection are employed.