Everyday footwear: An overview of what we know and what we should know on ill-fitting footwear and associated pain and pathology

Footwear has been used to protect feet for millennia with socially exclusive population adopting stylish and fashionable shoes with expensive materials. In terms of historic timeline, only more recently footwear has been worn by all classes in the western world as an integral part of their apparel. Traditionally, footwear has been constructed from natural materials, mainly leather, but has recently benefitted from the flexibility that technology has provided with a plethora materials and new design innovations. Although it has expanded the availability for a variety of consumers, the choice and fit continue to be problematic with many individuals wearing shoes that are ill-fitting. Provision of specific footwear advice for problem feet is poorly evidenced and is heavily practitioner dependant limiting its efficacy. There is limited understanding as to the changes that can occur from regularly wearing footwear that is unsuitable in shape, style and construction which is referred to as ill-fitting. Current research on the effect that everyday footwear has on foot function and pain focuses mainly on women’s shoes, particularly high heels. Defining what is a good fitting shoe, that does not damage the foot or mechanics of walking, may need to be individualised, but best fit is based on loose historical parameters rather than research evidence. The aim of this overview is to highlight aspects of current research, establishing what is known about the effect’s shoes have on the feet as well as exploring the mythology around footwear fit and advice that is often historical in nature.     

Generation and attenuation of transient impulsive forces beneath the foot: a review

At the end of the swing phase of gait, the moving foot generates a transient force, due to the exchange of momentum as it contacts the ground. This review article examines the transient, which is known as the heelstrike in walking and the footstrike in running. The resulting ‘shock wave’, which passes up the limb, may produce damage, leading to degenerative joint disease and a variety of other pathologies. Protection against transient forces is provided by limb positioning at initial contact, by the anatomical heel pad, by materials used in shoe construction and by the use of viscoelastic shoe inserts.     

Effects of footwear fixation on joint angle variability during straight gait in the elderly

BackgroundVarious types of footwear fixation can dramatically alter gait characteristics, and could potentially contribute to an increased risk of falls in the elderly. However, no studies have been conducted to analyze the effects of footwear fixation on joint angle variabilities, particularly during the entire gait cycle.Research questionDoes the fixation of footwear significantly affect the lower limb joint angle variabilities during the gait cycle?MethodsPrincipal component analysis (PCA) was conducted on 20 healthy adults using 3D spatio-temporal data of the pelvis and lower limb joint angle that were collected during the entire gait cycle with the footwear in various conditions (well-fixated footwear, less-fixated footwear, slippers, and bare feet). Kinematic waveforms were reconstructed from the PCA data, which were used to determine the distinct differences in joint angle variabilities between footwear conditions.ResultsThe results showed large variability in the knee- and ankle-joint angles on the sagittal plane when walking in the loose condition (less-fixated footwear, slippers, and bare feet) compared with those in the well-fixated footwear condition.SignificanceThese results demonstrate the effect of footwear fixation on the joint angle variabilities of the elderly while walking. The increase in the knee- and ankle-joint angle variabilities when walking with less-fixated footwear could be a risk factor for falls.     

A comparison of vertical force and temporal parameters produced by an in-shoe pressure measuring system and a force platform

Objective. To investigate the ability of Pedar in-shoe system to measure vertical force accurately, by comparing it with the Kistler force platform.

Design. In vivo experiment in normal subjects.

Background. It has been suggested Pedar is highly reliable, but absolute accuracy of the system with regard to force measurement has not been comprehensively tested.

Methods. Sampling at 99 Hz, using five healthy subjects, simultaneous data were collected barefoot, and in three types of shoes (Trainers, Oxfords, Slip-on Deck Type). Six variables obtained from the force/time curve from each footstep were compared.

Results. The temporal data recorded by Pedar correlated well with that obtained using Kistler, with significant differences only in overall duration of the step in Deck shoes (P<0.001) and Oxford shoes (P<0.01), and peak to peak barefoot (P<0.01). Pedar recorded a lower first peak force and mid-peak force in all cases (P<0.001). However, the magnitude of the 2nd peak force recorded by both systems was significantly different only in Trainers (P<0.05) and Oxford shoes (P<0.001). The impulse data obtained with Oxford shoes was not significantly different, although barefoot, Trainers and Deck shoes were significantly lower (P<0.001) for Pedar.

Conclusions. In most cases, comparison of data recorded by the two systems provided good evidence for the accuracy and reliability of temporal measurements and second peak force measurements taken with the Pedar in-shoe system.Relevance

In-shoe pressure data provides evidence for clinical decisions if the systems utilised are proven to be valid, repeatable and accurate. Comparison with an established force platform enables some assessment of these factors.     

Prevalence estimation and familial tendency of common forefoot deformities in Turkey: A survey of 2662 adults

Objective

This survey was designed to evaluate the prevalence estimations of HV, bunionette, hammertoe as well as their relations to shoe wearing and also familial tendency, in Turkey.

Do Fitflops™ increase lower limb muscle activity?

Background

Fitness toning shoes are becoming increasingly popular, they aim to increase muscle activity, raise energy expenditure and improve overall health while wearing them. Yet there is a lack of consensus in the literature regarding their effectiveness. One such shoe on the market is the Fitflop™ designed to activate leg muscles through density shifts in the shoe's sole. The purpose of this study was to investigate the effect of wearing Fitflops^TM on the muscle activity of the lower limb.

Methods

Twenty three females (age 20.8 (1.3)years, mass 62.9 (11.9)kg, height 165.4 (5.6)cm) participated in the study. Muscle activity of the medial gastrocnemius, biceps femoris, rectus femoris and gluteus maximus of the participants' right limb were recorded using surface electromyography during participation in three different tasks to simulate daily living activities. These were a) treadmill walking b) stair climbing and c) zigzag walking around cones. The participants completed the tasks barefoot, while wearing Fitflops™ and while wearing regular flip flops so that comparisons between muscle activity in the different shoe conditions could be made.

Findings

The results show that there was no significant difference in the activity of the medial gastrocnemius, biceps femoris, rectus femoris and gluteus maximus muscles across all shoe conditions and simulated daily activities (P > 0.05).

Interpretation

Based on these results, the use of Fitflops™ is not recommended as a means of increasing muscle activity of the medial gastrocnemius, biceps femoris, rectus femoris and gluteus maximus during activities of daily living in a healthy recreationally active female population.     

There is a difference in functional ankle stability between different types of footwear in male athletes: A cross-sectional study

ContextLateral ankle sprains (LAS) are among the most common injuries in sports, with a poor long – term prognosis due to high chronicity and recurrence rates. Chronic ankle instability (CAI) results up to 40% of people that endured a first – time LAS.ObjectiveThe aim of this study was to compare ankle stability between groups characterised by the use of different types of footwear during their sport activities.DesignCross-sectional study.SettingFirm training surface, local sport clubs.ParticipantsFifty - one male subjects were recruited, distributed in four groups based on the type of footwear they use during their sport activities.Main outcome measuresAll subjects performed four clinical ankle stability tests, and completed the Dutch version of the Cumberland Ankle Instability Tool (CAIT) and Profile of Mood States (POMS). All clinical ankle stability tests were performed barefoot.ResultsSubjects performing their sport activities barefoot scored better than subjects performing their sport with shoes at the multiple hop test (p = .002 to .047) and executed the figure–of–8 hop test significantly faster than subjects with submalleolar ankle support (AS) (p = .019). Subjects with submalleolar AS and studs showed significantly better results than subjects with supramalleolar AS on the CAIT– score (p = .024, p = .030) and the side– hop test (p = .050, p = .045). They also scored significantly better than subjects with submalleolar AS for the side – hop test (p = .032), foot – lift test (p = .019) and figure–of 8 hop test (p = .011).ConclusionBarefoot sports performing subjects appear to have better ankle stability compared to subjects performing their sports with shoe support. Subjects performing sports with high AS appear to have worst ankle stability.Level of evidence: Level III, Cross–sectional study.