The influence of insoles with a peroneal pressure point on the electromyographic activity of tibialis anterior and peroneus longus during gait

[Insoles in the treatment of pes planovalgus : A prospective, randomised, double-blind, placebo-controlled comparative trial of sensomotoric and supportive insoles]

BACKGROUND

In adults, flexible symptomatic flat foot is treated conservatively with supportive foot orthoses. Sensorimotor foot orthoses, however, are controversial due to insufficient data.

PURPOSE

Comparison of the effectiveness of sensorimotor and supportive foot orthoses in adults.

MATERIAL AND METHODS

In 73 patients, in addition to foot gymnastics, supportive, sensorimotor or placebo insoles were compared over 3 measurement points during 1 year as part of a double-blind, prospective, randomised placebo-controlled clinical trial using Numeric Rating-Scala, the Foot and Ankle Disability Index, as well as pedobarography and valgus index. The statistical analysis was performed using ANOVA with repeated measures.

RESULTS

The valgus index increased significantly with supportive foot orthoses. In the follow-up, the foot contact area was only significantly reduced with sensorimotor foot orthoses in static and dynamic measurements. Supportive foot orthoses led to a faster reduction in pain, but without reducing the contact area of the foot. There were no relevant differences in functionality.

CONCLUSIONS

The reduction of the contact surface in combination with sensorimotor foot orthoses shows the potential for muscular addressing of the flexible flat foot. There were no disadvantages compared to other treatments. Supportive foot orthoses led to a faster reduction in subjective complaints, but appear to weaken the muscles supporting the arch of the foot. In the longer term, consistent foot muscle training also appears to be effective, as wearing placebo foot orthoses also led to an improvement in subjective well-being without significant biomechanical changes.

Pain Reduction in Patellofemoral Knee Patients During 3-Month Intervention with Biomechanical and Sensorimotor Foot Orthoses: A Randomized Controlled Clinical Study

Background: Patellofemoral pain (PFP) significantly affects patients' daily activities and consequently reduces their quality of life. Custom-made foot orthoses (FOs) are a common method of medical treatment that positively influences biomechanical factors such as the kinematics of the lower extremity and reduces pain perception in patients. However, there is a gap in research regarding the influence of different FO treatments on knee pain. Therefore, this study addresses the impact of biomechanical foot orthoses (BMFOs) and sensorimotor foot orthoses (SMFOs) on patients with foot deformity and PFP. Methods: A total of 26 participants (9 men, 17 women; 27.7 ± 10.7 years; 175.0 ± 0.1 cm; 75.7 ± 18.8 kg; BMI: 24.7 ± 5.6) took part in this randomized controlled clinical trial. In the pre-test, knee pain was evaluated using the Kujala Anterior Knee Pain Scale after the physician's anamnesis and plantar pressure measurement. A 3-month intervention with SMFO and BMFO was performed, and weekly development was evaluated using 11-item visual analog scales (VASs). Repeated measures analyses of variance were used to assess differences between time of measurements (ToMs) and the interaction effect between ToMs and treatment groups (SMFO, BMFO). Results: Statistical analysis revealed no statistically significant interaction between ToMs and treatment groups but a significant main effect on Kujala anterior knee pain scores (MDiff = 10.189; p = 0.014) and 12-week VAS (p = 0.001). Conclusions: The findings indicate that both treatment approaches effectively alleviated perceived knee pain in the PFP sample with foot deformity, with neither approach demonstrating superior efficacy. This trial was registered in the WHO International Clinical Trials Registry Platform (ICTRP) and German Clinical Trials Register (DRKS00035082).

Assessing the Subjective Effectiveness of Sensorimotor Insoles (SMIs) in Reducing Pain: A Descriptive Multicenter Pilot Study

This pilot study aimed to investigate the use of sensorimotor insoles in pain reduction, different orthopedic indications, and the wearing duration effects on the development of pain. Three hundred and forty patients were asked about their pain perception using a visual analog scale (VAS) in a pre-post analysis. Three main intervention durations were defined: VAS_post: up to 3 months, 3 to 6 months, and more than 6 months. The results show significant differences for the within-subject factor "time of measurement", as well as for the between-subject factor indication (p < 0.001) and worn duration (p < 0.001). No interaction was found between indication and time of measurements (model A) or between worn duration and time of measurements (model B). The results of this pilot study must be cautiously and critically interpreted, but may support the hypothesis that sensorimotor insoles could be a helpful tool for subjective pain reduction. The missing control group and the lack of confounding variables such as methodological weaknesses, natural healing processes, and complementary therapies must be taken into account. Based on these experiences and findings, a RCT and systematic review will follow.

The effects of foot orthoses and sensory facilitation on lower limb electromyography: A scoping review

Foot orthoses (FO) are used as a treatment for biomechanical abnormalities, overuse injuries, and neuropathologies, but study of their mechanism remains inconclusive. The neuromotor paradigm has proposed that FOs may manipulate sensory input from foot sole skin to reduce muscle activity for movement optimization. This review argues that a FO likely alters the incoming mechanical stimuli transmitted via cutaneous mechanoreceptors and nociceptors as the foot sole interfaces with the surface of the orthotic. Thus, all FOs with or without intentional sensory facilitation, likely changes sensory information from foot sole cutaneous afferents. Additionally, in light of understanding and applying knowledge pertaining to the cutaneous reflex loop circuitry, FO's increasing sensory input to the motorneuron pool can change EMG to either reflex sign (increase or decrease). The purpose of this scoping review was to synthesize FO and sensory augmentation literature and summarize how FO designs can capitalize on foot sole skin to modulate lower limb electromyography (EMG). Six database searches resulted in 30 FO studies and 22 sensory studies that included EMG as an outcome measure. Results revealed task and phase specific responses with some consistencies in EMG outcomes between testing modalities, however many inconsistencies remain. Electrical stimulation reflex research provides support for a likely sensory-to-motor factor contributing to muscle activity modulation when wearing FOs. The discussion divides trends in FO treatment modalities by desired increase or decrease in each compartment musculature. The results of this review provides a benchmark for future academics and clinicians to advance literature in support of a revised neuromotor paradigm while highlighting the importance of foot sole skin in FO design.

Comparison of the influence of supportive and sensorimotor insoles in the muscle activity of tibialis anterior and peroneus longus in combat boots

INTRODUCTION

Flatfoot is a very common static deformity. It occurs frequently in soldiers and causes problems in the lower extremities. There is a lack of data regarding therapy with insoles, especially with sensorimotor insoles. The objective of this study was to investigate the influence in muscle activity of supporting/correcting and sensorimotor insoles in combat boots in the muscles of the lower limb and thus to draw conclusions according to the benefits of insole therapy in military footwear.

METHODS

73 patients (12 female, 61 males; average age: 30.8 ± 7.9 years) with pes planovalgus deformity were included in this prospective randomized placebo-controlled study. For intervention supporting (N = 23), sensorimotor (N = 28) and placebo insoles (N = 22) were used. During gait analysis muscle activity was measured by means of surface electromyography (EMG) of the tibialis anterior and peroneus longus muscle in combat boots with and without insoles. Statistical evaluation was performed using two-factor ANOVA with repeated measures.

RESULTS

EMG measures (amplitude, integral, maximum, mean) showed mainly activating effects in the peroneus longus muscle in the case of sensorimotor and activity reductions in supporting insoles. Comparing effects of different kinds of insoles to the peroneus longus muscle, significant differences could be shown. No significant differences in muscular activation were observed for the tibialis anterior muscle.

CONCLUSION

Even in combat boots effects of sensorimotor insoles on the peroneus longus muscle can be detected. The expected effects, attributed to the different kinds of insole, could be observed, too. While sensorimotor insoles had an activating kind of effect, supportive insoles reduced muscular activity of the peroneus longus. In contrast for the tibialis anterior muscle no clear conclusion could be drawn. Its muscular activity seems not to be influenced by insoles in combat boots. However, it remains unclear whether clinical long term effects, e.g. pain and function, can be improved.

Innovative Medial Cushioning Orthoses Affect Peroneus Longus Electromyographic Activity during Running

Background: Over-supination processes of the foot and ankle involving peroneus longus (PL) damage during running sports have been treated conservatively with passive control tools, such as tapes, braces, or external ankle supports, but the effect of orthoses with typical lateral wedging orthoses (TLWO) on the muscular activity of PL during running remains unclear. Here we investigate the effects of innovative medial cushioning orthoses (IMCO) on PL activity during the full running gait cycle. In addition, we wished to ascertain the effects of innovative medial cushioning orthoses (IMCO) on PL activity during running. Methods: Thirty-one healthy recreational runners (mean age 34.5 ± 3.33) with neutral foot posture index scores, were selected to participate in the present study. They ran on a treadmill at 9 km/h wearing seven different orthoses (NRS, IMCO 3 mm, IMCO 6 mm, IMCO 9 mm, TLWO 3 mm, TLWO 6 mm and TLWO 9 mm), randomly performed on the same day while electromyographic activity of the PL muscle was recorded. Statistical intraclass correlation coefficient (ICC) to test reliability was carried out and the Wilcoxon test with Bonferroni’s correction was developed to analyze the differences between the conditions. Results: the reliability of all assessments showed data higher than 0.81, that is, “almost perfect reliability”; all EMG PL values wearing either TLWO or IMCO showed a statistically significant reduction versus NRS during the fully analyzed running gait cycle; the highest difference was set on NRS 23.08 ± 6.67 to TLWO 9 mm 17.77 ± 4.794 (p < 0.001). Conclusions: Muscular EMG activity of the PL during the full running gait cycle decreases when wearing either TLWO or IMCO relative to NRS; therefore, these orthoses could be prescribed to treat the strain and overload pathologies of PL. In addition, IMCO—as it less thick, compared with TLWO—can be used when aiming to achieve better running economy.

Assessment of a New Lateral Cushioned Casting Orthosis: Effects on Peroneus Longus Muscle Electromyographic Activity During Running

Background:

Classical medial wedge (CMW) orthoses have been prescribed to treat overpronation foot pathologies in runners. The effects of a novel supination orthosis (NSO) on the surface electromyography (EMG) activity of the peroneus longus (PL) muscle during a complete cycle of running have yet to be tested.

Purpose/Hypothesis:

The purpose of this study was to compare the EMG activity of the PL in participants wearing CMW orthoses and NSOs versus neutral running shoes (NRS) during a full cycle of running gait. It was hypothesized that the PL muscle activity would be lower for the NSO compared with CMW or NRS.

Study Design:

Controlled laboratory study.

Methods:

Included were 31 healthy recreational runners of both sexes (14 male and 17 female; mean age, 38.58 ± 4.02 years) with a neutral Foot Posture Index and standard rearfoot-strike pattern. Participants ran on a treadmill at 9 km/h while wearing NSO (3-, 6-, and 9-mm thicknesses), CMW (3-, 6-, and 9-mm thicknesses), and NRS, for a total of 7 different conditions randomly selected, while the EMG signal activity of the PL was recorded for 30 seconds. Each trial was recorded 3 times, and the intraclass correlation coefficient (ICC) to test reliability of the measurements was calculated. The Wilcoxon pair to pair nonparametric test with Bonferroni correction was performed to analyze differences among the conditions.

Results:

The reliability of all assessments was almost perfect (ICC, >0.81). For both the CMW and NSO, regardless of thickness, the PL activity was statistically significantly lower compared with the NRS (P < .05 for all). For all CMW thicknesses, the PL activity was lower compared with the respective NSO thicknesses, with the 3-mm thickness having the largest difference (CMW_3mm, 18.63 ± 4.64 vs NSO_3mm, 20.78 ± 4.99 mV; P < .001).

Conclusion:

Both CMW and NSO produced reduced EMG activity of the PL muscle; therefore, they can be prescribed to treat overpronation pathologies without associated PL strain concerns. In addition, the NSO saved the enhancement material placed on the medial-rear side of CMW, making it easier to wear sports shoes.

Clinical Relevance:

Knowing the safety of CMW and NSO will aid in understanding treatments for overpronation pathologies.

Electromyographic Assessment of the Lower Leg Muscles during Concentric and Eccentric Phases of Standing Heel Raise

Only a small number of muscle activation patterns from lower limbs have been reported and simultaneous muscle activation from several lower limb muscles have not yet been investigated. The purpose of this study was to examine any gender differences in surface electromyography (EMG) activity from six recorded lower limb muscles of the dominant limb at baseline (i.e., with the foot placed flat on the floor and in the neutral position), and during concentric and eccentric phases when performing a heel raise task. In total, 10 females and 10 males performed a standing heel raise task comprising of three continuous phases: baseline, unloading (concentric muscle action), and loading (eccentric muscle action) phases. Muscle activation from six muscles (gastrocnemius medialis, gastrocnemius lateralis, soleus, tibialis anterior, peroneus longus, and peroneus brevis) were measured using the Myon 320 EMG System. Root mean squared values of each muscle were calculated for each phase. Descriptive and inferential statistics were incorporated into the study. Statistically significant p values were set at 0.05. The results showed no significant differences between baseline, concentric, and eccentric phases with respect to each of the muscles investigated. Except for the gastrocnemius medialis at baseline and concentric phases, no significant differences were observed between genders or contractions. The data suggests that gender does not significantly influence the eccentric phase during the standing heel raise task.

The immediate effects of sensorimotor foot orthoses on foot kinematics in healthy adults

BACKGROUND

Sensorimotor foot orthoses is an alternative concept, which in addition to mechanical effects, are designed to change muscle activation by altering sensory input to the plantar surface of the foot. However, there is little evidence of how these affect the kinematics of the foot during gait.

RESEARCH QUESTION

The aim of the study was to explore the immediate effect of calcaneal medial heel bars and retrocapital bars on foot kinematics during the stance phase of gait.

METHODS

Kinematic data were collected from 32 healthy individuals using an eight camera motion capture system and a six-degrees-of-freedom multi-segment foot model in three different orthotic conditions; calcaneal medial heel bar, retrocapital bar, and no orthosis. Vector field statistical analysis was performed to explore the effect of the orthotic conditions over the kinematic time series curves during stance phase. Peak median and interquartile ranges were also reported during the different phases of stance.

RESULTS

The calcaneal medial bar significantly decreased rearfoot eversion for the majority of the stance phase and compensatory increased midfoot eversion during the entire stance phase compared to the no orthosis condition. The retrocapital bar rotated the foot externally significantly abducting the rearfoot for the entire stance phase and the midfoot for the majority of stance phase.

SIGNIFICANCE

The calcaneal medial heel bar and retrocapital bar significantly altered the foot kinematics in a way that may benefit patients with abnormal pronation and intoeing gait.

Immediate effect of individual bars of insoles and their combination on gait parameters in asymptomatic healthy adults

Objective: The way how individual bars of sensorimotor insoles influence the gait kinematics is not fully understood yet. Therefore, this study aimed to explore the effect of three sensorimotor orthotic conditions (the medial calcaneal and retrocapital lateral bars and their combination) on the gait parameters in healthy adults during the stance phase of gait cycle.Materials and methods: Twenty-six young adults performed 20 gait cycles in each condition using their self-selected cadence and provided standardised shoes with the base-sole and the three types of orthotics. A three-dimensional motion analysis system (8 cameras; 200 Hz) was used and a six-degrees of freedom model was applied. The cadence, the stride length, the first peaks of foot external rotation, eversion and dorsal flexion as well as the first peak of hip adduction were analysed.Results: Significant differences (p < 0.05) were found for all parameters between the orthotic conditions, except the cadence. Significant difference in the first peak of hip adduction (p = 0.008) was found between the dominant and non-dominant leg. There were no significant interactions between the factors of condition and leg dominance (p > 0.05).Conclusions: There seems to be overall tendencies in immediate changes in ankle joint kinematics caused by all three sensorimotor orthotic conditions and besides the mechanical principles, also 'proprioceptive mechanism' seems to play a role. However, maximum observed average angular change was 2° and some variability in reactions to each orthotic condition exists among the individuals. Therefore, clinical relevance of such changes remains unclear and careful analysis of expected outcomes should be the common part of every orthotic intervention.

THE INFLUENCE OF SENSORIMOTOR TRAINING MODALITIES ON BALANCE, STRENGTH, JOINT FUNCTION, AND PLANTAR FOOT SENSITIVITY IN RECREATIONAL ATHLETES WITH A HISTORY OF ANKLE SPRAIN: A RANDOMIZED CONTROLLED PILOT STUDY

BACKGROUND

Ankle sprains frequently result in persistent sensorimotor deficits. Sufficient evidence of effects of sensorimotor training using unstable devices on physical functions is lacking. There is no insight as to whether simultaneous tactile stimulation of plantar foot mechanoreceptors using textured surfaces may influence outcomes in people with a history of ankle sprain.

PURPOSE

The purpose of this study was to investigate the potential effects of sensorimotor training using unstable textured surfaces on balance, strength, joint function, and plantar sensitivity in recreational athletes with a history of ankle sprain.

PARTICIPANTS

Nineteen recreational athletes (6 females, 13 males; mean age: 29 ± 7 years) with a history of ankle sprain and self-reported sensation of instability participated.

METHODS

Self-reported function of the ankle joint, plantar cutaneous detection threshold to light touch, balance during single-leg stance as well as maximal isometric strength of the ankle joint in eversion and inversion were measured. Participants were randomly allocated to either a training group using unstable textured surfaces or a training group using unstable smooth surfaces or a control group. Outcome measurements were repeated after six weeks of training and at follow-up after 10 weeks. Within and between group differences were analyzed using ANOVA, Friedman tests, or Kruskal Wallis tests (p<0.05) and post-hoc tests with Bonferroni correction. Correlations between outcome-parameters from baseline measurements were analyzed using Spearman's rho (p<0.05).

RESULTS

No significant between-group differences in all outcome measures were detected. However, a significant increase of strength in eversion was found for the training group using textured surfaces after 10 weeks (p = 0.01). A moderate correlation existed between plantar detection threshold of metatarsal head (MT) I and strength of inversion (r  =  0.51, p<0.05) before training across all groups. There were moderate negative correlations between balance parameters and strength in eversion (r  =  -0.57 - -0.64, p≤0.01) as well as plantar detection thresholds at MT V (r  =  -0.48 - -0.62, p<0.05) at baseline across all groups.

CONCLUSION

A six-week sensorimotor training using unstable smooth and textured surfaces demonstrated no significant differences in balance, strength in eversion and inversion, plantar foot sensitivity, and self-reported ankle instability between training groups and the control group in recreational athletes with a history of ankle sprain. A better score on balance testing seems to correlate with an increase in eversion ankle strength and a decreased plantar sensitivity at MT V.

LEVEL OF EVIDENCE

Level IIb.

Peroneal muscle activity during different types of walking

BACKGROUND

As the most common form of movement, walking happens not only on flat but also on uneven surfaces, where constant loss and regaining of balance occur. The main balancing function of the ankle joint is performed by tibial muscles. When changing inclination in a frontal plane, an essential balancing function is performed by the peroneal muscles. One of the methods for improving the activity of peroneal muscles is walking with different foot placement. The objective of this study was to analyze the activity of the peroneal muscles when performing different types of walking.

METHODS

Sixteen healthy participants took part in this study, walking on a flat surface (NORM), on a medial incline ramp with the plantar surface of the foot fully placed on the surface (FULL), and on a medial incline ramp with elevated lateral part of the foot (LAT). We monitored the changes of EMG signals in peroneus longus (PL), peroneus brevis (PB), tibialis anterior (TA), soleus (SOL), gastrocnemius medialis (GM) and gastrocnemius lateralis (GL) muscles. We monitored kinematic parameters (gait speed, stride length, contact time, foot position). The parametric ANOVA test and a non-parametric Friedman test were used at an alpha level of 0.05.

RESULTS

This study shows that the EMG activities of peroneal muscles increases when walking on the medial incline ramp. Statistically significant EMG differences were observed in the peroneal muscles, TA and GL muscles. We observe a very high percentage of normalized EMG value of the PL muscle in LAT walking. Walking on a medial incline ramp impacts the foot position, contact time, and stride length but not the gait speed.

CONCLUSIONS

Walking on a medial incline ramp could be an effective exercise to improve the neuro-muscular function of the peroneal muscles and, therefore, might be a suitable exercise for people with weakened ankle evertors.

The biomechanical effects and perceived comfort of textile-fabricated insoles during straight line walking

BACKGROUND

Orthotic insoles that are made of foam material often have less breathability and thus cause discomfort to the wearer. Given that a sandwich structure offers better porosity and breathability that would improve comfort, the impact of custom-made insoles made with three-dimensional spacer fabric is studied.

OBJECTIVES

To examine the biomechanical effects and subjective comfort of spacer-fabric insoles during walking.

STUDY DESIGN

Repeated measures.

METHODS

Plantar pressure and lower limb muscle activity data are collected from 12 subjects. Subjective perceived comfort is measured after five successful walking trials for each of the three different insoles worn: traditional insoles made with ethylene vinyl acetate and two types of spacer-fabric insoles.

RESULTS

Compared to the use of traditional insoles, there is a statistically significant reduction in the peak pressure (>8%) and pressure-time integral (>16%) in the toes and metatarsal head 1 with the use of the spacer-fabric insoles as the top layer. Insoles with two layers of spacer fabrics have the highest perceived comfort ( p < 0.01). However, there is no significant difference in the selected muscle activity for all three insoles.

CONCLUSION

Insoles with different arrangements of spacer fabrics allow changes in pressure patterns across the plantar foot and perception of comfort while walking. The findings enhance current understanding on the use of textile-fabricated materials, which provide alternative solutions for modifying insoles. Clinical relevance The key features of spacer fabric offer a viable option for different orthotic insole applications. The results will greatly contribute toward insole prescription, potentially enhancing the efficacy of orthotic performance and increasing the range of insole materials.

Effect of Insoles with a Toe-Grip Bar on Toe Function and Standing Balance in Healthy Young Women: A Randomized Controlled Trial

Objective

The aim of this randomized controlled study was to investigate the effects of insoles with a toe-grip bar on toe function and standing balance in healthy young women.

Methods

Thirty female subjects were randomly assigned to an intervention group or a control group. The intervention group wore shoes with insoles with a toe-grip bar. The control group wore shoes with general insoles. Both groups wore the shoes for 4 weeks, 5 times per week, 9 hours per day. Toe-grip strength, toe flexibility, static balance (total trajectory length and envelope area of the center of pressure), and dynamic balance (functional reach test) were measured before and after the intervention.

Results

Significant interactions were observed for toe-grip strength and toe flexibility (F = 12.53, p < 0.01; F = 5.84, p < 0.05, resp.), with significant improvement in the intervention group compared with that in the control group. Post hoc comparisons revealed that both groups showed significant improvement in toe-grip strength (p < 0.01 and p < 0.05, resp.), with higher benefits observed for the intervention group (p < 0.01). Conversely, no significant interaction was observed in the total trajectory length, envelope area, and functional reach test.

Conclusions

This study suggests that insoles with a toe-grip bar contribute to improvements in toe-grip strength and toe flexibility in healthy young women.

The effect of insole on muscle activity and muscle fatigue at sit to standing of tibialis anterior and gastrocnemius in adult male

[Purpose] The purpose of this study was to investigate the effect of differing insole height on the electromyographic (EMG) activity and muscle fatigue in tibialis anterior and gastrocnemius a lot of repeat college students from the desk during a sit to stand activity. [Subjects and Methods] For the 30 subjects males, let them wear insole in order. Using EMG equipment measured the difference in muscle vitality and muscle fatigue degree. All subjects were measured for 3 seconds in standing up from the chair. It has been measured total 3 times. [Results] The results stated above is as follows: It’s sitting to standing activity when there were no significant differences between the muscles. But sitting activity in muscle fatigue−calf muscle during standing activity correlated only. [Conclusion] The results of this study show that the change of the muscle fatigue may cause an in gastrocnemius muscle, so not recommended for the health of a case of running shoes.