Randomized clinical trial into the impact of rigid foot orthoses on balance parameters in excessively pronated feet

Effect of foot orthoses on balance among individuals with flatfoot: A systematic review and meta-analysis

Individuals with flatfoot have impaired proprioception owing to ligament laxity and impaired tendons, which can result in poor balance. Foot orthoses (FOs) have been reported to stimulate plantar mechanical receptors and are used to manage foot overpronation in individuals with flatfoot. However, the results of the use of FOs to improve balance are inconsistent. In this systematic review and meta-analysis, we aimed to identify and investigate the effects of FOs on balance in individuals with flatfoot. Electronic databases were searched for articles published before March 2023. Peer-reviewed journal studies that included adult participants with flexible flatfoot and reported the effects of FOs on balance were included and classified based on the study design: randomized control trials (RCT) and non-RCTs. Four RCT studies were retained, and their methodological quality was assessed (mean, 63.2%; range 47.3%-73.1%: high), as were three non-RCT studies (mean, 54.1%; range, 42.1%-68.4%: high). Meta-analysis was performed by calculating the effect size using the standardized mean differences between the control and FO conditions. Transverse-arch insoles immediately improved static balance after use. However, no immediate significant effect was found for medial archsupport FOs, cuboid-posting FOs, or University of California Berkeley Laboratory FOs during the study period (2-5 weeks) when compared with the controls. The transverse-arch insole is the most effective FO feature for improving static balance. However, the high heterogeneity between study protocols contributes to the lack of evidence for the effects of FO on balance in people with flatfoot.

Does medial calcaneal wedge improve static balance and load distribution in young adults with pronated foot?

BACKGROUND

Foot orthoses changing the momentum in the subtalar joint are often recommended, especially in activities loading the foot, to bring the pronated foot posture closer to neutral.

OBJECTIVES

To examine the immediate effect of medial heel wedge on static balance and load distribution in patients with increased pronation in the foot.

STUDY DESIGN

Experimental study design.

METHODS

Forty people with right dominant lower extremity participated in the study. For static balance assessment, we assessed ellipse surface, sway length, x-y mean, AP index, and Romberg ratio on 1 foot and measured load distribution as right-left foot and fore-hind foot with and without wedge.

RESULTS

There was a difference between the parameters of the ellipse surface and the Romberg ratio on the left side in the measurements performed with and without wedge for static balance on the left side ( P < 0.05) while there was no difference in the remaining values ( P > 0.05). In the load distribution, the change in the right anteroposterior foot was significant, increasing the load on the forefoot with the wedge ( P < 0.05) while we observed no difference in the left fore-hind foot load distribution and right-left foot load distribution ( P > 0.05).

CONCLUSION

Our study showed that for static balance, medial wedge can improve balance on the left side by decreasing sway, and for load distribution, the medial wedge changed the load distribution from back to front on the right side. These small differences in young healthy individuals are a preliminary indication that further studies are needed.

Can a rigid antipronation foot orthosis change the effects of prolonged standing on postural control in men with patellofemoral pain?

BACKGROUND

Pronated foot posture is known as a contributing factor for patellofemoral pain (PFP) development. Patients with patellofemoral pain often experience poor postural control. Implementation of optimal management strategies for enhancing their postural performance is important.

OBJECTIVES

The aim of this study was to determine whether a rigid antipronation foot orthosis changes prolonged standing effects on postural control in men with PFP.

STUDY DESIGN

Case-control study.

METHODS

Twenty-eight men with PFP and pronated foot and 28 healthy men were enrolled in this study. Center-of-pressure parameters were measured during short trials (60 seconds) of single-leg standing before and immediately after prolonged standing (20 minutes) using force platform. In patients with PFP, postural control was examined on 2 separate days with and without rigid antipronation foot orthosis.

RESULTS

Findings showed that the pre-post differences of sway area (t(48) = -2.22, p = 0.03), mediolateral (ML) displacement (t (48) = -2.51, p = 0.01), and mean velocity (t(48) = -2.01, p = 0.04) were significantly greater in patients with PFP without foot orthosis compared with those in the healthy group. Significant intervention main effect ( p = 0.04) and time-by-intervention interaction ( p = 0.006) for sway area were shown. Significant intervention main effects were noted for ML displacement ( p = 0.007) and mean velocity ( p = 0.003). For these variables, significant time-by-intervention interactions were found. Further analysis showed greater values of ML displacement and mean velocity parameters before the prolonged standing in patients with PFP without foot orthosis compared with patients with PFP with orthosis.

CONCLUSIONS

Rigid antipronation foot orthosis can improve the postural performance after prolonged standing in young adult men with PFP.

Effect of 3D printed foot orthoses stiffness on muscle activity and plantar pressures in individuals with flexible flatfeet: A statistical non-parametric mapping study

BACKGROUND

The 3D printing technology allows to produce custom shapes and add functionalities to foot orthoses which offers better options for the treatment of flatfeet. This study aimed to assess the effect of 3D printed foot orthoses stiffness and/or a newly design posting on muscle activity, plantar pressures, and center of pressure displacement in individuals with flatfeet.

METHODS

Nineteen individuals with flatfeet took part in this study. Two pairs of foot orthoses with different stiffness were designed for each participant and 3D printed. In addition, the flexible foot orthoses could feature an innovative rearfoot posting. Muscle activity, plantar pressures, and center of pressure displacement were recorded during walking.

FINDINGS

Walking with foot orthoses did not alter muscle activity time histories. Regarding plantar pressures, the most notable changes were observed in the midfoot area, where peak pressures, mean pressures and contact area increased significantly during walking with foot orthoses. The latter was reinforced by increasing the stiffness. Concerning the center of pressure displacement, foot orthoses shifted the center of pressure forward and medially at early stance. At the end of the stance phase, a transition of the center of pressure in posterior direction was observed during the posting condition. No effect of stiffness was observed on center of pressure displacement.

INTERPRETATION

The foot orthoses stiffness and the addition of posting influenced plantar pressures during walking. The foot orthoses stiffness mainly altered the plantar pressures under the midfoot area. However, posting mainly acted on peak and mean pressures under the rearfoot area.

Progressive Collapsing Foot Deformity. Is There Really a Johnson and Strom Stage I?

Johnson and Strom stage I posterior tibialis tendon dysfunction presents with pain and swelling but preserved function and no deformity. Diagnosis is clinical. Pathomechanics explains the overloading of the tendon that may be worsened by a tight gastrocnemius, but systemic inflammatory disease may also be responsible for a stage I condition. Medial heel wedged orthoses are effective in most patients. Surgery usually consists of an open/endoscopic tenosynovectomy. In cases of complete tendon rupture, flexor digitorum longus tendon transfer may be considered. Stage I patients with a higher risk of progression-inflammatory conditions, excessive laxity, obese-may benefit from a "prophylactic" medializing calcaneal osteotomy.

Assessment of Selected Spatio-Temporal Gait Parameters on Subjects with Pronated Foot Posture on the Basis of Measurements Using OptoGait. A Case-Control Study

Walking is part of daily life and in asymptomatic subjects it is relatively easy. The physiology of walking is complex and when this complex control system fails, the risk of falls increases. As a result, gait disorders have a major impact on the older adult population and have increased in frequency as a result of population aging. Therefore, the OptoGait sensor is intended to identify gait imbalances in pronating feet to try to prevent falling and injury by compensating for it with treatments that normalize such alteration. This study is intended to assess whether spatiotemporal alterations occur in the gait cycle in a young pronating population (cases) compared to a control group (non-pronating patients) analyzed with OptoGait. Method: a total of n = 142 participants consisting of n = 70 cases (pronators) and n = 72 healthy controls were studied by means of a 30 s treadmill program with a system of 96 OptoGait LED sensors. Results: Significant differences were found between the two groups and both feet in stride length and stride time, gait cycle duration and gait cadence (in all cases p < 0.05). Conclusions: pronating foot posture alters normal gait patterns measured by OptoGait; this finding presents imbalance in gait as an underlying factor. Prevention of this alteration could be considered in relation to its relationship to the risk of falling in future investigations.

Immediate, short and medium-term effects of orthopedic insoles with a metatarsal retro-capital bar on biomechanical variables, plantar pressures and muscle activity in running

BACKGROUND

The aim of this study was to evaluate the effect of 12 weeks of use of orthopedic insoles equipped with a metatarsal retro-capital bar (MRCB) on plantar pressure under the feet and lower limb kinematic variables during running.

METHODS

Two groups of 10 runners used for 12 weeks while running orthopedic insoles without correction or equipped with a MRCB. All participants performed successively a standing posture (CoP displacement) test and a running test at 11 km.h-1 (lower limb kinematic variables) using with flat insoles and orthopedic neutral or MRCB insoles at the beginning (T0), after 4 (T4) and 12 weeks (T12) of use.

RESULTS

For the MRCB group, CoP moved backwards while forefoot plantar pressure was decreased during standing position at T4 and T12 compared to T0. During running, the plantar pressure under the 2nd, 3rd and 4th metatarsal heads was reduced with MRCB at T0, T4 and T12. The one under the 1st metatarsal head was decreased at T4 and T12, when MRCB or flat insoles were used. The maximal extension and the total amplitude of ankle were slightly increased at T4 and T12 with or without wearing MRCB insoles. Similar changes in knee joint kinematics were observed but only at T12. Any significant changes were found in runners that used orthopedic insoles without correction.

CONCLUSIONS

Orthopedic insoles equipped with MRCB involve lower plantar pressure under the metatarsal heads, which may be of interest to treat forefoot injuries in runners.

Balance impairment in pediatric charcot-marie-tooth disease

INTRODUCTION

Balance impairment contributes to gait dysfunction, falls, and reduced quality of life in adults with Charcot-Marie-Tooth disease (CMT) but has been minimally examined in pediatric CMT.

METHODS

The CMT Pediatric Scale (CMTPedS) was administered to 520 children with CMT. Associations between balance function (Bruininks-Oseretsky Test of Motor Proficiency [BOT-2]) and sensorimotor and gait impairments were investigated.

RESULTS

Daily trips/falls were reported by 42.3% of participants. Balance (BOT-2) varied by CMT subtype, was impaired in 42% of 4-year-olds, and declined with age (P < 0.001). Vibration (P < 0.001), pinprick (P < 0.004), ankle dorsiflexion strength (P < 0.001), and foot alignment (P < 0.004) were associated with BOT-2 balance (adjusted R² = 0.28). The visual dependence of balance increased with age.

DISCUSSION

Balance impairment occurs from a young age in children with CMT. Balance intervention studies are required in pediatric CMT and should consider the degree of sensorimotor impairment, foot malalignment, and visual dependence. Muscle Nerve, 2019.

Comparing the immediate effects of UCBL and modified foot orthoses on postural sway in people with flexible flatfoot

BACKGROUND

Different types of foot orthoses have been prescribed for patients with flatfoot. Results of several studies have shown that orthoses were able to change balance parameters in people with flatfoot. However, the possible effect of orthosis flexibility on balance has not yet been investigated.

OBJECTIVES

The aim of the current study was to investigate the immediate effect of a rigid University of California Berkeley Laboratory (UCBL) foot orthosis, a modified foot orthosis, and a normal shoe on the postural sway of people with flexible flatfoot.

STUDY DESIGN

Quasi-experimental.

METHODS

In all, 20 young adults with flatfoot (aged 23.5 ± 2.8 years) were invited to participate in this study. The Biodex Stability System was employed to perform standing balance tests under three testing conditions, namely, shoe only, UCBL, and modified foot orthosis. Total, medial-lateral, and anterior-posterior sway were evaluated for each condition.

RESULTS

The results of this study revealed no statistical difference in the medial-lateral and anterior-posterior stability indices between foot orthoses and shoed conditions. The overall stability index with the UCBL foot orthosis, however, was significantly lower than that with the modified foot orthosis.

CONCLUSION

The UCBL foot orthosis was able to decrease total sway and improve balance in people with flexible flatfoot.

CLINICAL RELEVANCE

Results of previous studies have indicated that foot orthoses were able to affect the balance of people with flatfeet. However, the possible effects of flexible orthoses on balance have not been examined. The results of this study may provide new insight into material selection for those people with balance disorders.

Evaluation of standing stability in individuals with flatfeet

OBJECTIVE

Flatfoot is one of the most common foot disorders, which not only influences the performance of the foot but also affects the alignments of the ankle, knee, and hip joints. The performance of the flat-arched individuals differs from that of normal individuals during walking. However, there is not enough information in the literature regarding their standing stability. Moreover, the influence of use of foot insole on standing stability has not been evaluated. Therefore, the aim of this study was to evaluate standing stability in individuals with flatfoot with and without insole.

METHODS

Two groups of normal and flat-arched individuals were recruited into this study. A Kistler force plate was used to measure the center of pressure (CoP), which is recognized as a good approximation of sway of center of gravity in a horizontal plane. Stability was determined by calculating the CoP excursions, path length, and velocity in the mediolateral and anteroposterior directions. The difference between stability in normal individuals and those with flatfoot was examined using the independent t test. The paired t test was used to determine the difference between stability in each group with and without insole. Significant P value was set at α ≤.05.

RESULTS

There was a significant difference between stability of flat-arched and normal individuals based on CoP velocity and total velocity. In addition, there was no direct correlation between the severity of flatfoot and instability during quiet standing. However, the mean values of CoP total velocity during standing with and without insole were significantly different (P < .001).

CONCLUSION

This study suggests that individuals with flatfoot are more unstable when compared with normal individuals during quiet standing. It seems that the foot insole improves the alignment of foot structure and reduces the forces applied on the ligament, thus, improving standing stability. Therefore, stability assessment in patients with flatfoot may be important, and the insole is a useful modality that can be used to improve stability in this patient group.

LEVELS OF EVIDENCE

Therapeutic, Level II: Prospective, comparative trial.

The effects of exergaming on balance, gait, technology acceptance and flow experience in people with multiple sclerosis: a randomized controlled trial

Background

Exergaming is a promising new alternative to traditional modes of therapeutic exercise which may be preferable and more effective for people with Multiple Sclerosis (MS). Impaired balance is reported as one of the most disabling aspects of MS. The purposes of this study were to examine the effects of exergaming on: (1) postural sway, (2) gait, (3) technology acceptance and (4) flow experience in people with MS. Secondary outcomes were disability: 12‐item Multiple Sclerosis Walking Scale (MSWS-12) and the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) questionnaire.

Methods

Fifty-six adults (mean age = 52 years, SD = 5.8; 38 women) with a clinical diagnosis of MS and able to walk 100 meters with or without use of a walking aid were included in this study and randomized into 3 groups. Group 1 received balance training using the Nintendo Wii Fit™ (exergaming) and Group 2 undertook traditional balance training (non-exergaming). Group 3 acted as a control group, receiving no intervention. Exergaming and traditional balance training groups received four weeks of twice weekly balance-orientated exercise. Postural sway was measured using a Kistler™ force platform. Spatiotemporal parameters of gait were measured using a GAITRite™ computerised walkway. Technology acceptance and flow experience were measured using the Unified Theory of Acceptance and Use of Technology and the Flow State Scale questionnaires, respectively.

Results

There were significant improvements in bipedal postural sway in both intervention groups when compared to the control group; and no effects of either intervention on gait. There were no significant differences between the interventions in technology acceptance but on several dimensions of flow experience the Wii Fit™ was superior to traditional balance training. Both interventions showed improvements in disability compared to control.

Conclusions

In terms of the physical effects of exergaming, the Wii Fit™ is comparable to traditional balance training. These findings would support the use of the Wii Fit™ as an effective means of balance and gait training for people with MS, which is both accepted and intrinsically motivating to MS users.

Trial registration

Controlled Trials ISRCTN13924231.

Foot orthoses for adults with flexible pes planus: a systematic review

BACKGROUND

Foot orthoses are widely used in the management of flexible pes planus, yet the evidence to support this intervention has not been clearly defined. This systematic review aimed to critically appraise the evidence for the use of foot orthoses for flexible pes planus in adults.

METHODS

Electronic databases (Medline, CINAHL, Cochrane, Web of science, SportDiscus, Embase) were systematically searched in June 2013 for randomised controlled, controlled clinical and repeated measure trials where participants had identified flexible pes planus using a validated and reliable measure of pes planus and the intervention was a rigid or semi-rigid orthoses with the comparison being a no-orthoses (shoes alone or flat non-posted insert) condition. Outcomes of interest were foot pain, rearfoot kinematics, foot kinetics and physical function.

RESULTS

Of the 2,211 articles identified by the searches, 13 studies met the inclusion criteria; two were randomised controlled trials, one was a controlled trial and 10 were repeated measure studies. Across the included studies, 59 relevant outcome measures were reported with 17 calculated as statistically significant large or medium effects observed with use of foot orthoses compared to the no orthoses condition (SMD range 1.13 to -4.11).

CONCLUSIONS

No high level evidence supported the use of foot orthoses for flexible pes planus. There is good to moderate level evidence that foot orthoses improve physical function (medial-lateral sway in standing (level II) and energy cost during walking (level III)). There is low level evidence (level IV) that foot orthoses improve pain, reduce rearfoot eversion, alter loading and impact forces; and reduce rearfoot inversion and eversion moments in flexible pes planus. Well-designed randomised controlled trials that include appropriate sample sizes, clinical cohorts and involve a measure of symptom change are required to determine the efficacy of foot orthoses to manage adult flexible pes planus.

Effectiveness of a heel cup with an arch support insole on the standing balance of the elderly

Background

The use of insoles may enhance postural stability and prevent falls. The aim of this study was to design a new insole and to explore the effectiveness of the insole on the standing balance of the healthy elderly.

Methods

The study was conducted at a community hospital. Patients older than 65 years at an outpatient clinic without abnormal gait patterns, lower limb deformities, or foot pain were enrolled. The participants were assigned to good- and poor-stability groups on the basis of the stability index (SI), using the Biodex® Balance System. A heel cup with an arch support insole was provided. Participants wore the insole for 8 weeks for a minimum of 4 hours/day. A static balance test for SI was performed at the initial meeting and 8 weeks after the assigned insoles were worn for each participant.

Results

Five participants (10.0%) of 50 total did not finish the study. There were 25 patients in the good-stability group and 20 in the poor-stability group. The SI, before and after intervention, was significantly different for all 45 participants (3.244±0.688 versus 3.064±0.671; P<0.001). The differences in SI before and after the intervention both in the good-stability group (2.764±0.546 versus 2.592±0.538) and the poor-stability group (3.845±0.188 versus 3.655±0.128) were statistically significant (P<0.001). No statistically significant difference on changes of SI were seen between the two groups.

Conclusion

The results suggest a heel cup with arch support insole is effective in enhancing the standing balance of the elderly. This may be of benefit in preventing falls.

Orthotic intervention and postural stability in participants with functional ankle instability after an accommodation period

CONTEXT

Most protocols established to treat patients with functional ankle instability (FAI) have focused on taping the ankle. Orthotic intervention is a different treatment protocol that may have a positive effect on these patients, especially after an accommodation period.

OBJECTIVE

To determine whether the use of a prefabricated orthotic affects postural stability in patients with FAI and a control group.

DESIGN

Randomized controlled clinical trial.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Forty patients with unilateral FAI.

INTERVENTION(S)

Postural stability was measured on both limbs using a force plate on 3 occasions. Participants were instructed to balance on 1 limb with their eyes closed for 20 seconds. In session 1, postural stability was measured with the patient wearing his or her own athletic shoes. The control group repeated this procedure in sessions 2 and 3. When those in the orthotic group returned for session 2, they received prefabricated, full-length Quick Comfort Insoles for both feet, immediately placed the orthotics in their shoes, and were tested for postural stability. Patients in the orthotic group were instructed to wear the inserts daily and return 2 weeks later for session 3 and repeat postural stability testing.

MAIN OUTCOME MEASURE(S)

Center of pressure.

RESULTS

In the orthotic group, postural stability improved between sessions 1 and 2 and sessions 1 and 3. In session 3, postural stability was different for the orthotic and control groups. We also identified a difference between the limbs such that the FAI ankle displayed worse postural stability than did the healthy ankle.

CONCLUSIONS

Prefabricated orthotics improved postural stability in participants with FAI. Similar to the findings of previous researchers, we found that postural stability was worse in FAI ankles than in healthy ankles.

Impact of soft and hard insole density on postural stability in older adults

A significant predictor of falls in the elderly population is attributed to postural instability. Thus, it is important to identify and implement practical clinical interventions to enhance postural stability in older adults. Shoe insoles have been identified as a mechanism to enhance postural control, and our study aimed to evaluate the impact of 2 shoe insoles on static standing balance in healthy, older adults compared with standing posture while barefoot. We hypothesized that both hard and soft shoe insoles would decrease postural sway compared with the barefoot condition. Indeed, excursion distances and sway areas were reduced, and sway velocity was decreased when wearing insoles. The hard insole was also effective when visual feedback was removed, suggesting that the more rigid an insole, the greater potential reduction in fall risk. Thus, shoe insoles may be a cost-effective, clinical intervention that is easy to implement to reduce the risk of falling in the elderly population.

The evaluation of walking footwear on postural stability in healthy older adults: an exploratory study

BACKGROUND

It has been proposed that walking footwear enhances postural stability in healthy older adults. The aim of the study is to evaluate differences between two different types of athletic footwear in relation to postural stability in healthy older adults.

METHODS

A convenience sample of 21 healthy older adults with mean (SD) of 74 (5) years was recruited. Postural stability was measured using a force plate for anterior-posterior (AP) and mediolateral (ML) centre of pressure excursion for 30s with eyes closed and open using two different types of athletic footwear. Each participant performed three repetitions of bipedal standing. Two-way analysis of variance tested the interaction effect of the footwear and eye conditions on anterior-posterior (AP) and mediolateral (ML) postural sway.

FINDINGS

There was no significant footwear-eye condition interaction for anterior-posterior(AP) postural sway but there were significant main effects for both the footwear and eye conditions (P<0.05). The significant main effects for the footwear conditions occurred between barefeet and the two shoe conditions, but not between the two shoe conditions. For mediolateral (ML) postural sway there was no significant interaction effect and no main effects for the footwear and eye conditions (P>0.05).

INTERPRETATION

The results suggest that older adults demonstrate an initial destabilisation effect which could possibly be of benefit to functional ability but the long-term effects of ability of athletic footwear to enhance postural stability requires further investigation.

The short-term effects of treating plantar fasciitis with a temporary custom foot orthosis and stretching

STUDY DESIGN

Prospective single-group cohort study.

OBJECTIVES

To identify the effectiveness of a temporary custom foot orthosis (TCFO), followed by a stretching program, for the treatment of plantar fasciitis (PF).

BACKGROUND

PF, a common cause of heel pain, often leads to disability. Optimal treatment for this often challenging clinical condition is still unknown.

METHODS

Fifteen individuals with PF were recruited from the general public. All participants received a TCFO and were instructed to wear it for 2 weeks while weight bearing. Following the initial 2 weeks, participants were weaned off of the TCFO and instructed to begin a daily stretching program. Follow-up appointments occurred at 2, 4, and 12 weeks. The primary outcome measures included first-step heel pain via numeric pain rating scale (NPRS), the Foot and Ankle Ability Measure activities of daily living subscale (FAAM-A), and the Foot and Ankle Ability Measure sports subscale (FAAM-S). Secondary outcome included the global rating of change (GRC) score.

RESULTS

Individuals with a primary complaint of plantar foot pain entered and completed this study. Repeated-measures ANOVAs for the NPRS, FAAM-A, and FAAM-S showed statistically significant changes (P<.001). Post hoc analysis using paired t tests demonstrated statistically and clinically significant change at all follow-up times, compared to the initial intervention (P<.001). Mean GRC scores at 2, 4, and 12 weeks were 4.4, 4.5, and 4.2, respectively.

CONCLUSION

In treating PF, a TCFO used for 2 weeks, followed by a stretching program, provided preliminary evidence that first-step heel pain and foot and ankle function improve in the short term and up to 12 weeks.

LEVEL OF EVIDENCE

Therapy, level 2b.

Efficacy of knee braces and foot orthoses in conservative management of knee osteoarthritis: a systematic review

A systematic analysis was conducted on the effectiveness of knee braces and foot orthoses in conservative management of knee osteoarthritis. The methodologic quality of the randomized clinical trials, controlled clinical trials, and observational studies were systematically reviewed using the Structured Effectiveness Quality Evaluation Scale. Twenty-five studies met the inclusion criteria. The orthoses used in the studies included Generation II osteoarthritis knee brace, valgus knee braces, functional off-loading knee braces, knee sleeves, lateral-wedged insoles with subtalar strapping, medial-wedged insoles, and specialized footwear. Results suggest that knee braces and foot orthoses are effective in decreasing pain, joint stiffness, and drug dosage. They also improve proprioception, balance, Kellgren/Lawrence grading, and physical function scores in subjects with varus and valgus knee osteoarthritis. Knee braces and foot orthoses could be cautiously considered as conservative management for relief of pain and stiffness and improving physical function for persons with knee osteoarthritis. The conclusions of this review are limited by methodologic considerations like poor quality of trials and heterogeneity of interventions.

Normative values for the Foot Posture Index

Background

The Foot Posture Index (FPI) is a validated method for quantifying standing foot posture, and is being used in a variety of clinical settings. There have however, been no normative data available to date for comparison and reference. This study aimed to establish normative FPI reference values.

Methods

Studies reporting FPI data were identified by searching online databases. Nine authors contributed anonymised versions of their original datasets comprising 1648 individual observations. The datasets included information relating to centre, age, gender, pathology (if relevant), FPI scores and body mass index (BMI) where available. FPI total scores were transformed to interval logit scores as per the Rasch model and normal ranges were defined. Comparisons between groups employed t-tests or ANOVA models as appropriate and data were explored descriptively and graphically.

Results

The main analysis based on a normal healthy population (n = 619) confirmed that a slightly pronated foot posture is the normal position at rest (mean back transformed FPI raw score = +4). A 'U' shaped relationship existed for age, with minors and older adults exhibiting significantly higher FPI scores than the general adult population (F = 51.07, p < 0.001). There was no difference between the FPI scores of males and females (2.3 versus 2.5; t = -1.44, p = 0.149). No relationship was found between the FPI and BMI. Systematic differences from the adult normals were confirmed in patients with neurogenic and idiopathic cavus (F = 216.981, p < 0.001), indicating some sensitivity of the instrument to detect a posturally pathological population.

Conclusion

A set of population norms for children, adults and older people have been derived from a large sample. Foot posture is related to age and the presence of pathology, but not influenced by gender or BMI. The normative values identified may assist in classifying foot type for the purpose of research and clinical decision making.

Effect of textured foot orthotics on static and dynamic postural stability in middle-aged females

Foot orthotics (FO) may be prescribed for a range of lower limb and foot conditions. Prior studies report use of FO in enhancing postural stability in healthy younger adults, and do not control for footwear type. Currently, interest in the effects of FO on postural stability in older adults has increased. Limited reports exist of the effects on postural stability of FO made of combinations of materials, thicknesses and surface textures. In this study 40 healthy females (51.1+/-5.8 years) recruited into a within subject test-retest randomised clinical trial were provided with identical footwear and randomised into four FO conditions (control, grid, dimple and plain, n=10 for each condition). Participants wore the footwear for 4 weeks, a minimum of 6h/day. A Kistler force plate was used to determine postural stability variables (anterior-posterior displacements and medial-lateral displacements) for each participant in a static position, with eyes open and eyes closed. Base of support was evaluated using the GAITRite system. Each outcome measure was measured at baseline and 4 weeks. Postural stability variables demonstrated no significant differences between the four FO conditions. No significant differences were observed with base of support between the four conditions. We have demonstrated no detrimental effects on postural stability in older females after 4 weeks. This is regardless of orthotic texture and is independent of footwear. Biomechanical or sensory effects of FO on postural stability are still to be determined. These may be dependent on the geometry and texture of the orthotic.

Effect of flat insoles with different Shore A values on posture stability in diabetic neuropathy

The objective of the study was to determine whether insoles with a low Shore A value (15 degrees) as prescribed for patients with a diabetic neuropathy have a negative effect on posture stability because these insoles may reduce somatosensory input under the feet. It was conducted in the Center for Rehabilitation, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands The study was observational and conducted on 30 diabetic patients (aged 37 - 82 years) with a neuropathy. Posture stability (body sway) was assessed in a shoe without insole, on a flat insole with a low Shore A value (15 degrees) and on a flat insole with a higher Shore A value (30 degrees). These assessments were done under four different conditions: (1) eyes open, no dual-task, (2) eyes closed, no dual-task, (3) eyes open, dual-task (mental arithmetic) and (4) eyes closed, dual-task. Additionally 10 healthy controls (aged 27 - 51 years) were assessed similarly. A significantly higher root-mean-square (rms) value of the anterior-posterior velocity, V(y), was found in patients compared with controls (3.4 cm/s vs. 1.2 cm/s, p < 0.05). Also a significant difference in rms value of the anterior-posterior velocity, V(y), was found between eyes open and eyes closed (1.9 cm/s vs. 2.7 cm/s, p < 0.05). No significant effects were found for insoles or dual tasks for the total group. In diabetic patients no significant effect was found of insoles on posture stability. The effect of closed eyes on posture stability was significantly larger for diabetic patients compared to controls. It was found that prescribing insoles with a low Shore A value (15 degrees), compared to insoles with a higher Shore A value (30 degrees) has no significant negative effect on posture stability in patients with a diabetic neuropathy.

Effect of orthoses on postural stability in asymptomatic subjects with rearfoot malalignment during a 6-week acclimation period

OBJECTIVE

To determine the effect of custom-fitted orthoses on postural sway over a 6-week acclimation period.

DESIGN

Repeated-measures analysis of variance on postural sway measures with factors being group (control, malaligned), time (initial, 2 wk, 4 wk, 6 wk postintervention), and condition (with orthoses, without orthoses). For single-limb stance, side (right, left) was analyzed to determine bilateral differences.

SETTING

Biodynamics laboratory.

PARTICIPANTS

Twenty-one subjects, 11 asymptomatic with rearfoot malalignment and 10 asymptomatic with normal rearfoot alignment.

INTERVENTIONS

Orthoses were prescribed and worn for 6 weeks. Balance testing was performed on 4 different dates with each subject tested in both orthotic conditions. Postural control was measured with three 10-second eyes-closed trials for single-limb stance, one 20-second eyes-closed bilateral stance with the platform moving, and one 20-second eyes-open bilateral stance with the platform and surroundings moving.

MAIN OUTCOME MEASURES

Sway velocity (in deg/s) for single-limb stance and equilibrium score for bilateral stance.

RESULTS

Postural sway measures were significantly decreased during single-limb testing with orthoses versus without orthoses, regardless of group. The orthotic intervention significantly improved bilateral stance equilibrium score in the malaligned group at weeks 2, 4, and 6 when compared with measures at the initial week. Equilibrium score of the malaligned group with orthoses at initial week was significantly lower (worse) than the control group with orthoses at initial week; however, these results were not repeated during measurements taken at weeks 2, 4, or 6.

CONCLUSIONS

The application of orthoses decreased sway velocity for single-limb stance, improving postural stability regardless of group when visual feedback was removed. During bilateral stance, postural stability was initially worse for the malaligned group with and without orthoses when compared with the control group; however, improvements were seen by week 2 and continued throughout the remainder of testing. Clinically, the application of orthoses appears to improve postural control in people with rearfoot malalignment, particularly when vision is removed.

A systematic review of the effects of shoes and other ankle or foot appliances on balance in older people and people with peripheral nervous system disorders

The objective of this paper is to identify and review all publications on effects ankle and/or foot appliances (AFA) on balance in older people (>or=60 years) and patients with peripheral nervous system disorders (PNSD). These two groups account for the majority of the population with deteriorated balance due to peripheral somatosensory feedback problems. To provide a context for understanding and interpreting the studies that have been published to date, we will briefly summarize current theories on the role of somatosensory mechanisms in control of balance and how balance can be affected by AFA. A systematic literature review is presented in which publications were searched in Medline, Embase and Recal. In total 146 papers were identified and 18 were selected based on title and abstract for qualitative assessment by two independent reviewers. Based on assessment of the total articles, seven of the 18 papers fulfilled predetermined qualitative criteria and were selected for detailed review. No definitive conclusions can be drawn concerning the effects of AFA on balance in older people or in patients with PNSD because of the small number of studies and the weak level of evidence. The available literature seems to indicate that a training program may be helpful in ensuring the effectiveness of an appliance. Insoles with tubing or vibrating elements may improve balance, whereas thick or soft soles may deteriorate balance. The effects of these different types of insoles or soles are consistent with theories about somatosensory mechanisms that play a role in control of balance. More and better quality research is needed to support the prevalent use of appliances in these populations.

The effect of 6 weeks of custom-molded foot orthosis intervention on postural stability in participants with >or=7 degrees of forefoot varus

OBJECTIVE

Postural stability (PS) was assessed in a group of participants with >or=7 degrees of forefoot varus (FV) after 6 weeks of custom-molded functional foot orthosis (FO) intervention to investigate the effect of FO intervention in a population that may have decreased PS due to their foot structure.

DESIGN

A force platform was used to assess right and left single-limb stance position and eyes open and eyes closed condition PS.

SETTING

PS was assessed in a biomechanics research laboratory.

PARTICIPANTS

Twelve participants with >or=7 degrees of FV (MFV) and 5 participants with <7 degrees of FV (LFV) participated in the study.

INTERVENTIONS

PS of the MFV group was assessed initially when FOs were received and after 6 weeks of FO intervention. The LFV group PS was assessed during initial and 6-week testing sessions.

MAIN OUTCOME MEASURES

The root mean square of the center of pressure velocity was used to quantify single-limb stance PS during no FO and FO conditions.

RESULTS

LFV group PS did not change significantly (P=0.829) over the 6-week time period. Significant improvement was, however, reported in the MFV group anteroposterior (P=0.003) and mediolateral (P=0.032) PS at the 6-week assessment versus the initial assessment during both the noFO and FO conditions.

CONCLUSIONS

Six weeks of FO intervention may significantly improve PS in participants with >or=7 degrees of FV both when wearing FOs and when not wearing FOs.