The effects of textured materials on static balance in healthy young and older adults: A systematic review with meta-analysis

Capitalizing on skin in orthotics design: the effects of texture on plantar intrinsic foot muscles during locomotion

Foot orthoses (FO) are a commonly prescribed intervention to alter foot function during walking although their effects have been primarily studied in the extrinsic muscles of the foot. Furthermore, enhancing sensory feedback under the foot sole has been recently shown to alter extrinsic muscle activity during gait; however, the effects of FOs with enhanced sensory feedback on plantar intrinsic foot muscles (PIFMs) remain unknown. Thus, the purpose of this study was to investigate the effect of FOs with and without sensory facilitation on PIFM activity during locomotion. Forty healthy adults completed a series of gait trials in non-textured and textured FOs when walking over hard and soft flooring. Outcome measures included bilateral joint kinematics and electromyography (EMG) of four PIFMs. Results of this study highlight the distinct onset and cessations of each PIFM throughout the stance phase of gait. PIFMs remained active during mid-stance when wearing FOs and textured FOs facilitated muscle activity across the stance phase of gait. Increasing cutaneous input from foot sole skin, via the addition of texture under the foot sole, appears to alter motor-neuron pool excitation of PIFMs. Future academics are encouraged to increase our understanding on which pathologies, diseases, and/or medical conditions would best benefit from textured FOs.

Impact of five floor coverings on the orthostatic balance of healthy subjects

Plantar skin sensitivity contributes to the regulation of postural control and, therefore, changing the characteristics of the plantar support surface can modify this control. This study aimed at assessing the impact of five different floor coverings on the orthostatic balance in 48 healthy subjects. Static posturography was performed with eyes open or closed on a platform in a control condition (no covering) and with five different covering surfaces: foam, silicone, ethyl vinyl acetate, and two textured mats with small (height 2 mm) or large pimples (7 mm). The average velocity of center of pressure (CoP) displacement was the primary endpoint measure and ten other posturographic variables were assessed. Comfort and pain produced by the covering were also scored. In eyes open condition, the average velocity of CoP displacement was increased when subjects stood on the foam mat, the silicone mat, and especially the textured mat with large pimples. Several other posturographic variables showed significant changes with different types of floor coverings with eyes open. These changes were not correlated to the comfort or pain scores associated with the different surfaces. In contrast, no difference was observed compared to the control condition (no covering) with eyes closed. This study shows that adding smooth or textured floor covering can alter balance in eyes open condition. In eyes closed condition, although more disturbing for balance, healthy subjects achieved better postural adaptation, probably by mobilizing more of their proprioceptive resources. This posturographic examination procedure could, therefore, be used to assess "proprioceptive reserve" capacities in clinical practice.

Telerehabilitation in Low-Resource Settings to Improve Postural Balance in Older Adults: A Non-Inferiority Randomised Controlled Clinical Trial Protocol

Background: Several exercise methods with virtual reality devices have been used in treatments for older adults and patients with neurodegenerative diseases, although the mechanisms continue to be elucidated. The aim of this study is to establish the feasibility and effectiveness of a rehabilitation programme using low-cost virtual reality aimed at improving postural balance in older adults. It also seeks to compare low-cost virtual reality under two delivery modalities, telerehabilitation (TR) in elderly centres and face-to-face (FtF) in rehabilitation centres. Methods: The study is set up as a non-inferiority two-arm parallel triple-blind randomised controlled clinical trial. Sixteen persons aged 65 to 75-years-old will be included. Eighteen Wii therapy sessions (25-30 min) will be provided through both FtF (control group, n = 8) and TR (exposure group, n = 8), both with a Nintendo Wii balance board. Data will be collected at baseline (week 0), during the Wii therapy sessions (weeks 2, 4, and 6), and during the follow-up (weeks 8 and 10). The primary outcome will be the area of centre-of-pressure (CoP) sway; secondary outcomes will be medial-lateral and anterior-posterior velocity and standard deviation of CoP; and tertiary outcomes will be clinical measures: single-leg stand, timed up-and-go tests, Barthel Index, and Tinetti's scale. Statistical analyses will be performed using SPSS 20.00 for Windows. The trial adheres to the Declaration of Helsinki and the Chilean laws of rights and duties of the patient and research in humans. Ethical approval was obtained from the Ethics Committee of the University of Talca. Written informed consent will be obtained from participants. Discussion: In this trial, older adults from a Chilean city with a large rural and underserved population share will be included to test the feasibility and effectiveness of a rehabilitation programme using low-cost VR aimed at improving postural balance to generate evidence to support decision makers generating public health policy. Trial registration: Australian New Zeeland Clinical Trials Registration (ACTRN12621001380886).

Postural control telerehabilitation with a low-cost virtual reality protocol for children with cerebral palsy: Protocol for a clinical trial

OBJECTIVE

To establish the feasibility and effectiveness of a rehabilitation programme using low-cost virtual reality aimed at improving postural control in children with cerebral palsy-spastic hemiplegia. It also aims to compare the effectiveness of this programme under two delivery modalities, telerehabilitation (TR) and face-to-face (FtF).

METHODS

This is a registered randomized controlled clinical trial protocol (ACTRN12621000117819). Eighteen sessions of low-cost virtual reality therapy will be provided through both, FtF and TR modalities using a Nintendo Wii balance board. Each programme will last for 6 weeks and will consist of 3 sessions per week of 25 minutes each. Twenty patients diagnosed with cerebral palsy-spastic hemiplegia will be recruited for each group: FtF or TR (n = 40). Participants will be assessed at baseline, by the end of weeks 2, 4, and 6, and at weeks 8 and 10 (post-intervention follow-ups). The primary outcome will be the Center of Pressure sway area (CoParea); secondary outcomes will be standard deviation and velocity of the CoP in the mediolateral and anterior-posterior directions; tertiary outcomes will include the Modified-Modified Ashworth Scale for lower limbs, Modified Ashworth Scale for upper limbs, timed up-and-go tests, the timed one-leg standing and 6-minute walk test.

RESULTS

This study provides an assessment of the feasibility and effectiveness of an affordable rehabilitation programme using low-cost virtual reality aimed at improving postural control in children with cerebral palsy.

CONCLUSION

The designed rehabilitation programme using low-cost virtual reality may improve postural control in children with cerebral palsy-spastic hemiplegia. The TR modality is likely to be as effective as the FtF modality. The TR programme has been designed to overcome access barriers to physiotherapy services for children with cerebral palsy in low-resource settings, remote areas, and in restricted mobility contexts.

Is Postural Control Affected in People with Patellofemoral Pain and Should it be Part of Rehabilitation? A Systematic Review with Meta-analysis

BACKGROUND

Growing evidence supports that exercise therapy is effective for patellofemoral pain (PFP) rehabilitation. Nevertheless, the improvements have been reported not to be sustained in the long term, suggesting that the current protocols may not comprehend all required functional factors to provide a consistent recovery. A potential neglected factor in treatment protocols for PFP is postural control. However, it is unclear whether this population presents balance impairments or the influence of postural control on pain and function during rehabilitation programmes.

OBJECTIVE

To investigate whether (Q1) balance is impaired in people with PFP compared to controls, (Q2) conservative interventions are effective to improve balance in people with PFP, and (Q3) balance exercises are effective to improve pain and function in people with PFP.

DATA SOURCES

Medline, Embase, CINAHL, SPORTDiscus, Web of Science and Cochrane Library, supplemented by hand searching of reference lists, citations and relevant systematic reviews in the field.

METHODS

A systematic review with meta-analysis was conducted according to the Cochrane recommendations and reported according to the PRISMA statement recommendations. We included cross-sectional studies comparing balance between people with and without PFP; and randomised controlled trials verifying the effect of conservative intervention on balance and the effect of balance intervention on pain and function in people with PFP. The risk of bias was assessed using the Epidemiological Appraisal Instrument for cross-sectional studies and the Physiotherapy Evidence Database scale for randomised controlled trials.

RESULTS

From 15,436 records, 57 studies (Q1 = 28, Q2 = 23, Q3 = 14) met the eligibility criteria. Meta-analyses indicated that people with PFP have worse anteroposterior (very low grade evidence, standardised mean difference [SMD] = 1.03, 95% CI 0.40-1.66) and mediolateral (moderate grade evidence, SMD = 0.87, 95% CI 0.31-1.42) balance compared to controls. Moderate grade evidence indicated that overall balance is not affected in people with PFP (SMD = 0.38, 95% CI - 0.05-0.82). Low to very low grade evidence indicates that interventions are ineffective for mediolateral (SMD = 0.01, 95% CI - 0.51-0.53) and overall (SMD = 0.49, 95% CI - 0.14-1.11) balance improvements, and low grade evidence indicates that interventions are effective to improve anteroposterior balance (SMD = 0.64, 95% CI 0.04-1.23). Moderate to low grade evidence indicated that balance interventions are effective to reduce pain (SMD = 0.82, 95% CI 0.26-1.38) and improve function (SMD = 0.44, 95% CI 0.09-0.80) when measured using questionnaires; and very low grade evidence indicated no efficacy for function measured via functional tests (SMD = 0.73, 95% CI - 0.16-1.61).

CONCLUSION

People with PFP likely present balance deficits compared to asymptomatic people. There was insufficient evidence to support the efficacy of interventions to improve or modify balance in people with PFP. Also, there was insufficient evidence to support the efficacy of balance exercises to improve pain and function in people with PFP. Trial Registration The present systematic review was registered in PROSPERO (CRD42018091717).

Immediate effect of textured insoles on the balance in patients with diabetic neuropathy

AIMS/INTRODUCTION

Neuropathy is a common complication of diabetes that reduces balance by disrupting vision, and the sensory and vestibular systems. This is important in older adults who are more at risk of falling. Studies show that improving the sensory mechanisms through insoles can improve balance in people with balance disorders. As textured insoles have recently been considered for improving balance disorders, this study aimed to investigate the immediate effect of textured insoles on the balance of patients with diabetic neuropathy.

MATERIALS AND METHODS

A total of 17 patients with diabetic neuropathy participated in this quasi-experimental study. The studied variables were the general balance index, posterior-anterior balance index and medial-lateral balance index, which were measured in three conditions: (i) soft textured insoles; (ii) hard textured insoles; and (iii) without textured insoles. A Biodex balance device was used for this purpose.

RESULTS

In the general balance index, there was a significant difference between all the studied conditions. In the posterior-anterior balance index, there was a significant difference between without textured insole and hard textured insoles, and also soft and hard textured insoles. In the medial-lateral balance index, there was a significant difference between the hard textured insoles and without textured insoles, and also soft and hard textured insoles (P < 0.05).

CONCLUSIONS

Wearing textured insoles can increase the balance in patients with diabetic neuropathy. This can be due to its effect on the sensory feedback of the soles, improving the proprioception and tactile sensors that are the main sources of balance.

Effect of Phase-Change Materials on Laboratory-Made Insoles: Analysis of Environmental Conditions

Thermal comfort is essential when wearing a postural-corrective garment. Discomfort of any kind may deter regular use and prolong user recovery time. The objective of this work is therefore to optimize a new compound that can alter the temperature of orthopedic insoles, thereby improving the thermal comfort for the user. Its novelty is a resin composite that contains a thermoregulatory Phase-Change Material (PCM). An experimental design was used to optimize the proportions of PCM, epoxy resin, and thickener in the composite and its effects. A Box-Behnken factor design was applied to each compound to establish the optimal proportions of all three substances. The dependent variables were the Shore A and D hardness tests and thermogravimetric heat-exchange measurements. As was foreseeable, the influence of the PCM on the thermal absorption levels of the compound was quantifiable and could be determined from the results of the factor design. Likewise, compound hardness was determined by resin type and resin-PCM interactions, so the quantity of PCM also had some influence on the mechanical properties of the composite. Both the durability and the flexibility of the final product complied with current standards for orthopedic insoles.

The effect of texture under distinct regions of the foot sole on human locomotion

Sensory feedback from the foot sole plays an important role in shaping human locomotion. While net muscle activity and kinematic changes have been correlated with electrical stimulation to five topographical regions of the foot, it remains unknown if these responses are similar with tactile stimulation. The purpose of this study was to use texture in foot orthosis design, applied to five distinct regions under the foot sole, and measure joint kinematics, location of center of pressure, and muscle activity of eight lower leg muscles during level and incline walking. Fifty-five healthy adults completed 48 walking trials in textured and non-textured foot orthoses. Study results confirm that tactile stimulation is stimulation-site and gait-phase specific in modulating lower leg muscle activity during walking. For example, texture under the lateral forefoot consistently generated a suppression of EMG and texture under the lateral midfoot always generated a facilitation. In early stance, adding texture under the medial midfoot or calcaneus facilitated extensor muscle activity and suppressed flexor muscle activity. Texture under the lateral midfoot or medial forefoot facilitated tibialis posterior activation. These results support the topographical organization of cutaneous mechanoreceptors in foot sole skin while considering how texture can be used in foot orthosis design to target lower leg muscular changes during locomotion.

Neuromuscular response to the stimulation of plantar cutaneous during walking at different speeds

BACKGROUND

A lot of authors have been studied the consequence of postural control strategies through investigating the effects of foot-surface contact. In this context an important variable of textured surfaces or insoles could be related to material stiffness. We apply a particular textured insoles to evaluate neuromuscular response of plantar stimulation during walking.

RESEARCH QUESTION

Could textured insoles alter the human locomotion during walking at different speeds?

METHODS

Ten adults (age: 27 ± 5 years) completed three trials on the multifunction treadmill at 0.42 ms^-1, 0.89 ms^-1, and 1.5 ms^-1 walking speed. Temporal-spatial parameters, gait line, and kinetic parameters were analyzed. The Co-Contraction Index (CCI) and electromyography (EMG) of the right leg muscles were assessed during four phases of gait: first half stance (FHS), half stance (HS), second half stance (SHS), swing phase (SP). Textured insole and soft control insole were worn while walking.

RESULTS

Plantar stimulation improved cadence, stride time, stride length and gait line parameters with increasing speed. First force peaks and maximum force forefoot were always significant. The maximum force midfoot was significant at 0.42 and 0.89 ms^-1. The maximum force heel only was significant in lower velocity. The maximum pressure showed different significant values except for the heel. Significant differences in the CCI were always found in the FHS and SHS for the plantar muscles, and in the FHS and HS for the knee muscles. The differences in gait analysis in biomechanical and in electromyographic parameters were more significant in the higher speed tested.

SIGNIFICANCE

The perception of shape and texture through its linear response to skin deformation over a wide range of deformations could be the reason why the significant differences increase in the higher speed. In conclusion, sensory interventions fallowing appropriate insoles can influence significantly gait. Walking strategy positively adjusts locomotion with high efficiency.

A comparison of the efficacy of textured insoles on balance performance in older people with versus without plantar callosities

BACKGROUND

Textured insoles have been suggested to enhance foot sensation, which contributes to controlling upright balance. However, the interaction between plantar callosity and the textured surface has not been studied.

RESEARCH QUESTION

Firstly, to compare the efficacy of textured insoles on balance performance and foot position sense between two groups of older people: one group had plantar callosity, and the other did not. Secondly, to investigate the efficacy of textured insoles within each study group.

METHODS

Thirty older people with a history of falls (15 with plantar callosity and 15 without callosity) participated in this study. All participants underwent assessments of postural sway on a force plate, joint position sensation of the ankle with a slope box, and mobility using the "Timed Up and Go" test under three insole surface conditions: 1) smooth (control), 2) placebo and 3) textured surface. Two-way analyses of variance were used to compare the outcomes of the two groups and three conditions.

RESULTS

Older people with plantar callosity had worse ankle joint position sense and slower antero-posterior and mediolateral postural sway velocity than their peers who did not have plantar callosity. The textured insoles improved ankle joint position sense and mobility regardless of callus status in the plantar surface of older peoples' feet. The insole-callosity interaction was not significant for any study outcome.

SIGNIFICANCE

Textured insoles could be beneficial to older people with and without callosity as they have shown immediate improvements in ankle joint position sense and mobility.

Comparison of Plantar Sensitivity, Dynamic Balance, and Lower Extremity Joint Range of Motion Between Experienced Female Ballet Dancers and Female Non-Dancing Athletes: A Cross-Sectional Study

OBJECTIVES

Ballet dancers may increasingly use plantar sensory feedback to control foot position and movement during dance activities. Balance and joint range of motion (ROM) are important factors in ballet and may be related to plantar sensation in ballet dancers. Data on related functions of female ballet dancers compared to female non-dancing athletes are sparse. The aims of the study were twofold: 1. the relationships between plantar sensitivity and dynamic balance as well as between joint ROM and dynamic balance were determined in experienced female ballet dancers and female non-dancing athletes; and 2. the differences of plantar sensation, joint ROM of the lower limb, and dynamic balance between experienced female ballet dancers and female non-dancing athletes were investigated.

STUDY DESIGN

In this cross-sectional study, 21 subjects (11 experienced female ballet dancers and 10 female non-dancing athletes; median age: 23, range: 11 years; median body height: 1.7 m, range: 0.2 m; median body mass: 59 kg, range: 36 kg) were included. Plantar sensitivity was determined by Semmes-Weinstein monofilaments, active ranges of motion of the hip, knee, and ankle joints were measured using a goniometer and dynamic balance was assessed by the Y-Balance test. Correlations between outcome measures were determined in both groups. Outcome measures were compared between ballet dancers and non-dancing athletes using parametric or non-parametric statistical tests (α = 0.05).

RESULTS

For the fifth metatarsal head and the heel, higher correlations between plantar sensitivity and Y-Balance test scores in non-dancing athletes compared to ballet dancers were found. Higher correlations between joint ROM and Y-Balance test scores were determined for certain movements in non-dancing athletes compared to ballet dancers. A significantly lower cutaneous threshold was only found for the fifth metatarsal head in ballet dancers compared to non-ballet dancers (p < 0.05). Range of motion was significantly higher in ballet dancers for almost all movements (p < 0.05). Ballet dancers showed significantly higher normalized scores of the Y-Balance test (p ≤ .001).

CONCLUSIONS

Results of correlation analyses may indicate that non-dancing athletes increasingly must rely on plantar sensation of the fifth metatarsal head and the heel while maintaining dynamic balance compared to ballet dancers, especially in posterolateral direction of the Y-Balance test. Active joint range of motion of the lower extremity and dynamic balance differ between female ballet dancers and non-dancing athletes. Plantar sensitivity is not different for most of the assessed localizations.

The effect of age, sex and a firm-textured surface on postural control

In previous studies, the influence of plantar sensation has been examined using various textured surfaces with different stiffness materials to assess static balance. This study investigated the effects of a Firm Textured Surface (FTS) along with age and sex-related influences on postural control under different visual conditions. Forty subjects (20 elderly, 10 males, mean age 68.30, 10 females, mean age 68.00, and 20 young people, 10 males, mean age 25.45, 10 females, mean age 27.30) participated in this study maintained a quiet standing on FTS, foam and firm surfaces with eyes open and closed. The center of pressure displacement (CoP_DISP), CoP velocity (CoP_VEL), and sway velocity of the CoP in anteroposterior (AP) and mediolateral (ML) direction (V_A/P and V_M/L) were measured. FTS was associated with lower postural sway measures in both the groups with eyes open and closed. However, the foam surface showed the worst results in all postural parameters under all experimental conditions. Separate four-way ANOVAs were applied to each dependent variable. The main effects of surface (p < 0.0001), vision (p < 0.0001) and age (p < 0.0001 for CoP_DISP, CoP_VEL and V_A/P; p = 0.0003 for V_M/L) were significant in each of the four fitted models. Sex was never significant, either as a main effect or an interaction with other experimental factors. Eyes open were able to reduce the negative effects of the foam surfaces but without vision the proprioceptive sensory system cues of the body state become more important for maintaining balance. A good stimulation with rigid texture should be considered as relief to reduce the physiological-related decline of afferent information with age.

Biomechanical analysis of single-leg stance using a textured balance board compared to a smooth balance board and the floor: A cross-sectional study

BACKGROUND

Previous research showed that standing on textured surfaces can improve postural control by adapting somatosensory inputs from the plantar foot. The additional stimulation of plantar cutaneous mechanoreceptors by a textured surface during single-leg stance on a balance board may increase afferent information to the central nervous system to accelerate muscular responses and to enhance their accuracy. The additional impact of textured surface during single-leg stance on a balance board on postural control and muscle activity is unknown.

RESEARCH QUESTION

To investigate the differences of a) postural control during single-leg stance on a textured balance board compared to a smooth balance board and b) activity of lower extremity muscles during single-leg stance on a textured balance board compared to a smooth balance board and the floor.

METHODS

Twenty-six healthy adults (12 females, 14 males; mean age = 25.4 years) were asked to balance on their randomly assigned left or right leg on a force plate (floor; stable condition), a textured balance board and a smooth balance board (unstable conditions). Center of pressure (CoP) displacements (force plate, Bertec, 1000 Hz) and electromyographic activity (EMG) of eight leg muscles were measured and compared between conditions, respectively.

RESULTS

Neither CoP-displacements, nor EMG activities differed significantly between the textured and the smooth balance board (p > 0.05). Significantly higher muscle activities (p < 0.05) were observed using the balance boards compared to the floor.

SIGNIFICANCE

Single-leg stance using a textured balance board seems not to lead to reduced CoP-displacements compared to a smooth balance board. Muscle activation is significantly increased in both balance board conditions compared to the floor, however, it is not different when both balance board surfaces are compared. It could not be recommended to use a textured balance board for altering muscle activity and improving postural control during single-leg stance in favor of a smooth textured balance board.

Can Insoles Be Used to Improve Static and Dynamic Balance of Community-Dwelling Older Adults? A Systematic Review on Recent Advances and Future Perspectives

This systematic review investigated the effects of orthopedic, vibrating, and textured insoles on the postural balance of community-dwelling older adults. Articles published in English from 1999 to 2019 investigating the effects of (a) orthopedic, (b) vibrating, and (c) textured insoles on static and dynamic balance in community-dwelling older adults were considered. Twenty-four trials with a total of 634 older adults were identified. The information gathered generally supported the balance-improving effects of orthopedic, vibrating, and textured insoles in both static and dynamic conditions among community-dwelling older adults. Further examination found that rigidity, texture patterns, vibration thresholds, and components like arch supports and heel cups are important factors in determining whether insoles can improve balance. This review highlights the potential of insoles for improving the static and dynamic balance of community-dwelling older adults. Good knowledge in insole designs and an understanding of medical conditions of older adults are required when attempts are made to improve postural balance using insoles.

The effect of support surface and footwear condition on postural sway and lower limb muscle action of the older women

BACKGROUND

Diminished somatosensory function is a critical age-related change which is related to postural instability in the older population. Footwear is a cost-effective way to modulate the postural stability by altering sensorimotor inputs via mechanoreceptors on the plantar surface of the feet. Compared to insoles with indentions in the entire surface, we innovatively developed a textured insole with site-specific nodulous protrudous. This study thus aimed to investigate the immediate effect of the nodulous insole and supporting surface condition on static postural stability and lower limb muscle activation for healthy older women.

METHODS

This is a single-session study with repeated measurements. Twenty-three healthy older women stood on the firm (i.e., concrete floor) and foam surfaces with their eyes open in the three footwear conditions, namely barefoot, plain shoes and shoes with an innovative textured insole, for 30 seconds. Static postural sway and muscle activation of biceps femoris (BF), vastus lateralis (VL), tibialis anterior (TA), and lateral gastrocnemius (LG) of the dominant leg were measured during each testing condition.

RESULTS

Compared to a firm surface, standing on the foam could significantly increase the body sway and lower limb muscle activation (p<0.05). When standing on the foam, compared to barefoot, wearing footwear significantly decreased the VL and TA muscle activation and minimize the postural sway in medial-lateral and anterior-posterior direction, while the influence is larger for the shoes with nodulous insloe compared to the plain shoes. No significant differences between the footwear conditions for static stability and muscle activation were observed on firm surface condition.

CONCLUSIONS

For older women, footwear could improve the postural stability in the unstable surface, particularly the footwear with nodulous insole, with the underlying mechanism as enhancing the mechanoreceptors on the plantar surface of the feet.