Midfoot Width Research Articles

Changes in Foot Width in Minimally Invasive Bunionectomy

Category: Bunion; Midfoot/Forefoot Introduction/Purpose: Hallux Valgus (HV) is a common foot condition often requiring surgical intervention. Minimally invasive bunionectomy (MISB) has gained popularity for HV correction. While previous research has focused on distal foot width changes following surgery, this study introduces a novel midshaft measurement to assess proximal transverse midfoot width. The study aims to provide a comprehensive evaluation of foot width changes post-MISB. Methods: A retrospective review of prospectively collected data was conducted for 44 patients who underwent MISB for HV via an institutional outcome registry. Demographic data, surgical details, radiographs, and foot width measurements were collected. Changes in hallux valgus angle (HVA) and intermetatarsal angle (IMA) were also measured. The novel midshaft bony and soft tissue foot width measurements were included. Two independent observers conducted all preoperative and postoperative measurements. Results: Intraclass correlation coefficients (ICCs) demonstrated high interobserver reliability (all ICCs >0.70) for all measurements. MISB resulted in a consistent reduction in distal foot width, both bony (8.17%) and soft tissue (5.24%)(p < 0.001). These reductions correlated with changes in HVA and IMA, suggesting the extent of deformity correction influenced distal foot width (all r > 0.375, p < 0.05). However, the study revealed that proximal foot width, as measured by midshaft bony width, increased (5.27%) in the majority of cases (p < 0.001). Changes in midshaft foot width showed no correlation with HVA or IMA alterations. Conclusion: MISB for HV leads to an increase in midshaft foot width due to the unique mechanics of the procedure. Simultaneously, there is a decrease in distal foot width, which correlates with the extent of deformity correction. This results in a more uniform foot width. These findings may influence patient satisfaction, comfort, and shoe wear capabilities post-surgery. Further research should assess patient perception and comfort regarding these foot width changes after MISB.

Foot Anthropometry Measures in Relation to Treatment in Patients with Rheumatoid Arthritis: A Longitudinal Study.

Approximately 90% of patients with arthritis exhibit forefoot deformities, including deformities within the metatarsophalangeal and proximal interphalangeal joints. Current pharmacological treatment with Disease Modifying Antirheumatic Drugs (DMARDs) consists of two groups: synthetic drugs (sDMARDs) and biological drugs (bDMARDs). The objective of our study was to investigate foot anthropometry changes in RA patients based on the administered treatment over a five-year period Method: A longitudinal analysis was conducted with RA patients who were grouped based on their pharmacological treatment. The pharmacological treatment groups were categorized into (I) methotrexate (MTX), (II) MTX plus biological treatments (including all variables), (III) biological treatment alone, and (IV) a miscellaneous group comprising patients with diverse treatments, including patients for whom various drugs had failed or who had not achieved remission with pharmacological treatment. For the anthropometric measurements, a foot measurement platform validated by McPoil et al. was used. Post hoc analyses with Bonferroni correction were performed to identify pairwise differences between the treatment groups while controlling for Type I errors due to multiple comparisons. Results: In the period from 2018 to 2023, significant changes were observed in several foot measurements. For instance, the MTX group showed a statistically significant increase in left heel width (p = 0.026). The MTX group experienced a slight increase in left foot length, while the Biologics and MTX + Bio groups exhibited more substantial increases in both maximum medial arch height and midfoot width. Conclusions: Different RA treatments can have a significant impact on foot structure over a five-year period, showing notable changes in heel width and overall foot morphology. Combined treatments with MTX and biologics potentially offer better management of RA.

Changes in Foot Width in Minimally Invasive Bunionectomy.

Minimally invasive bunionectomy (MISB) has emerged as a popular approach to treat symptomatic hallux valgus deformity. Although previous studies focused on distal foot width changes postsurgery, this research introduces a novel midshaft measurement to evaluate proximal transverse midfoot width, aiming for a comprehensive understanding of foot changes post-MISB. A retrospective review of 44 HV patients from an institutional registry was conducted. Demographic data, surgical details, radiographs, and foot width measurements were collected. Changes in hallux valgus angle (HVA) and intermetatarsal angle (IMA) were also measured. Intraclass correlation coefficients (ICCs) demonstrated good to excellent interobserver reliability (all ICCs > 0.70) for all measurements. MISB resulted in a consistent reduction in distal foot width (P < .001). These reductions correlated with changes in HVA and IMA, suggesting that the extent of deformity correction influenced distal foot width: distal bone width decreased an average of 8 mm, P < .001). However, midshaft bony width increased an average of 4 mm, P < .001). Changes in midshaft foot width showed no correlation with HVA or IMA alterations. We found in this cohort of 44 patients that MISB for HV leads to an expected decrease in distal bony foot width but, on average, an increase in midshaft foot width.

Effects of Plantar Fascia Release and the Use of Foot Orthoses Affect Biomechanics of the Medial Longitudinal Arch of the Foot: A Cadaveric Study.

The aim of the study is to evaluate the effect of minimally invasive ultrasound-guided fascial release and a foot orthoses with first metatarsal head cutout on the biomechanics of the medial longitudinal arch of the foot in cadaveric specimens. A cross-sectional study was designed (20 body donors). Anthropometric measurements of the foot, foot posture index, and the windlass test and force were measured in different conditions: unloaded, loaded position, with foot orthoses, after a 25% plantar fascia release and after a 50% release. For the anthropometric measurements of the foot, differences were found in foot length ( P = 0.009), arch height ( P < 0.001), and midfoot width ( P = 0.019) when comparing the unloaded versus foot orthoses condition. When foot orthoses were compared with 25% plantar fascial release, differences were found in foot length ( P = 0.014) and arch height ( P < 0.001). In the comparison with 50% plantar fascial release, differences were found in the arch height ( P < 0.001). A significant interaction between foot orthoses condition and grades was found in the arch height during the windlass test ( P = 0.021). The results indicate that the presence of foot orthoses leads to a significant increase in arch height compared with other conditions. Furthermore, when plantar fascia release is performed, the arch does not exhibit any signs of collapse.

Static and dynamic plantar foot shape following long-term use of military boots

Foot structure can be influenced by various factors, such as footwear, body weight and physical activity. A change in foot structure can alter shock absorption and force transition. The main objective of this study is to investigate the effect of the long-term use of military boots on foot shape parameters. Thirty military and thirty non-military subjects participated in this case-control study. All participants had been regularly wearing military boots for the past 12 years. After introducing the experiment, static and dynamic footprints were recorded via paper and ink while standing and walking. The footprints were analysed using ImageJ software to extract foot width indices, area indices, truncated arch index, footprint index and arch angle index. The findings indicated no significant difference in comparison static and dynamic variables in the military and non-military groups (p ≥ 0.05). However, there was a significant difference between the two groups in both static (midfoot area, arch index (AI), truncated arch index, footprint index and arch angle index) and dynamic (midfoot width, Staheli Index (SAI), truncated arch index and arch angle index) conditions, when static and dynamic variable were compared (p &lt; 0.05). Findings revealed the military personnel have low arch, making them susceptible to musculoskeletal disorders. To mitigate this risk, it is recommended that military boots be reassessed or that insoles be used. Furthermore, it is suggested that military boots be limited to specific activities and fewer hours of usage to avoid potential health issues.

A Method-Comparison Study Highlighting the Disparity between Osseous- and Skin-Based Measures of Foot Mobility.

This study examined the validity of standard clinical measures of arch height mobility, midfoot width mobility (MWM), and foot mobility magnitude (FMM) relative to skin-based and osseous measures derived from radiographs. Skin-based clinical indices of foot mobility were calculated from standard, caliper-based measures of foot length, midfoot width, and dorsal arch height of the left limb of 20 healthy participants (8-71 yr) during non-weight-bearing and weight-bearing. Skin-based radiographic and osseous indices were derived from concurrent anteroposterior and lateral radiographs. Agreement between skin-based clinical and skin-based radiographic measures of foot mobility with those of osseous measures was investigated using the Bland and Altman approach. Foot mobility indices derived from clinical measures were significantly higher (20%-50%) than skin-based radiographic measures ( P < 0.01), which were, in turn, significantly higher (200%-250%) than osseous measures ( P < 0.01). Clinical measures demonstrated significant levels of proportional bias compared with radiographic measures of foot mobility ( P < 0.01). The contribution of osseous movement to skin-based clinical measures of mobility was highly variable between individuals, ranging between 19% and 81% for arch height mobility, between 4% and 87% for MWM, and between 14% and 75% for FMM. The limits of tolerance for clinical measures of foot mobility ranged from ±3.2 mm for MWM to ±6.6 mm for measures of FMM. The limits of tolerance for skin-based clinical and skin-based radiographic measures were generally larger than osseous movement with weight-bearing. Skin-based measures of foot mobility, whether clinical or radiographic methods, are not interchangeable and are poor indicators of osseous mobility. Although further research regarding the utility of osseous measures is warranted, these findings strongly caution against the use of skin-based clinical measures of foot mobility in clinical and research settings.

Transitioning to Barefoot Running Using a Minimalist Shoe Intermediary: A Prospective Cohort Study.

The objectives of this study are, first, to investigate the probability of runners successfully transitioning from running in a traditional shoe to barefoot. Second, to identify prognostic indicators of failure of transition to barefoot running. Over 20 wk, 76 healthy runners (female, 40; age, 35.04 yr [SD, 8.9 yr]; body weight, 69.9 kg [SD 13.4 kg]) attempted to transition from running in traditional shoes to running barefoot. A minimalist shoe was used as an intermediary. Participants ran for 4 wk exclusively in provided traditional shoes followed by 4 wk of transitioning to minimalist shoes. This process was repeated to transition to barefoot running. Participants were followed up until they withdrew from the study or successfully transitioned to running barefoot. A survival analysis examined the weeks of successful transition. Along with sex and age, baseline measures of traditional shoe overall comfort, footstrike pattern, midfoot width mobility and plantar foot pressure pain threshold were examined as prognostic variables for failure to transition using Cox regression. The cumulative probability of successful transition to running barefoot was 70.8% (95% confidence interval [CI], 61%-83%). The primary footwear-related reason for withdrawal was pain, primarily in the foot ( n = 7), two runners had confirmed injuries. Runners exhibiting a rearfoot strike pattern and higher midfoot width mobility were more likely to fail to transition (hazard ratios [HR], 4.02; 95% CI, 1.33-12.16 and HR, 1.22; 95% CI, 1.05-1.42). Most runners who wish to run barefoot will be able to transition. Our study indicates that there may be biomechanical and anatomical characteristics that are prognostic of failing to transition when using a 20-wk transition period and an intermediary minimalist shoe. Whether a different transition process increases the probability of a success remains to be seen.

Association between the Strength of Flexor Hallucis Brevis and Abductor Hallucis and Foot Mobility in Recreational Runners

Different measurements of foot morphological characteristics can effectively predict foot muscle strength. However, it is still uncertain if structural and postural alterations leading to foot pronation could be compensated with more efficient function of the intrinsic foot muscles and how mobility and strength are associated. Additionally, the relationship between foot mobility and the strength of the intrinsic muscles that control the foot arch is still unclear. Therefore, this study aimed to investigate the morphological parameters between dominant and non-dominant feet and the relationship between the intrinsic foot muscle strength and foot mobility in recreational runners. We used a cross-sectional study design to evaluate twenty-four healthy recreational runners (minimum 15 km/week) with an average training history of 70 ± 60 months. Foot Posture Index (FPI-6), isometric intrinsic muscle strength, overall morphology, and normalized mobility of both feet were assessed. Parametric tests analyzed the unidimensional measures, and paired analysis determined differences between dominant and non-dominant sides. Pearson’s and Spearman’s correlation coefficients determined the relationships between normalized strength and the variables of interest (CI = 95%). There was no significant association between intrinsic foot muscle strength and mobility. The only difference observed was between the dominant and non-dominant foot regarding the normalized foot length and midfoot width during non-weight-bearing, with small and medium effect sizes, respectively. Neither foot morphology nor foot mobility was associated with strength from intrinsic foot muscles in healthy recreational runners. Further work should explore the relationship investigated in our study with professional athletes and runners with symptomatic lower limb injuries to potentialize training and rehabilitation protocols.

Children’s foot parameters and basic anthropometry — do arch height and midfoot width change?

The aims of this study were as follows: (1) to assess how foot posture and morphology assessments change according to body mass index (BMI) status; (2) to determine which body composition parameter (BMI or waist circumference) correlates better with the foot posture index (FPI), arch height index (AHI), and midfoot width (MFW) in children. Foot morphometry (FPI, AHI, and MFW) and body composition (BMI and waist circumference (WC)) were assessed in a cross-sectional study of 575 children (mean age = 7.42 ± 1.67 years; 53.27% female). When comparing BMI groups, an increase of 8.3% in AHI and 13.6% in MFW (both p < 0.0001) was seen. In linear regression analyses, BMI and WC were positively associated with MFW explaining together 64.8% of its variance. Noteworthy, MFW is the most related to body composition parameters.Conclusion: Foot morphology assessed by FPI, AHI, and MFW differs among BMI categories in children. Noteworthy, WC correlates better with foot measures than does the more commonly used BMI, and more importantly the MFW is the foot measure best explained by children’s body weight. Since foot morphometry is different among different BMI groups, children would benefit from shoes with different patterns (thinner and wider), as well as a good system to adjust midfoot height.What is Known:• Children who are overweight and obese have flatter feet, when assessed using footprints.• Up to 72% of people have incorrectly fitted shoes.What is New:• Children with underweight have thinner and flatter feet than children with normal weight, while children with overweight and obesity have wider and higher arched feet.• Body weight is related to foot shape, which has relevance for footwear manufacturers.

Does the Nonweightbearing Foot Position Replicate the Neutral Calcaneal Stance Position in an Adult Population?

The neutral calcaneal stance position (NCSP), despite its known issues, is currently used as an "ideal" measure compared with the resting stance position in clinical podiatric medicine. The nonweightbearing (NWB) foot position, as used in the foot mobility magnitude (FMM), can provide an alternative comparative position, which is partially validated, if a significant correlation between the NCSP and the NWB position exists. This study aimed to establish the correlation between the component measures of the FMM in the NCSP and the NWB foot position of the FMM. Eighty participants were recruited. Measures of dorsal arch height (DAH) and midfoot width (MFW) were obtained at the 50% total foot length mark in the NCSP and the NWB position by two examiners using the apparatus described by McPoil et al. Reliability analysis with intraclass correlation coefficients (ICCs) indicated intrarater results of 0.90 to 0.99 for DAH and 0.96 to 0.99 for MFW and interrater results of 0.90 for DAH and 0.96 for MFW in the NWB position. Using a Pearson product moment correlation coefficient analysis, there was a significant correlation between the NCSP and the NWB position for DAH (r = 0.82) and MFW (r = 0.86). A significant correlation between the NCSP and the NWB position was evident when the measures of DAH and MFW were conducted. Therefore, clinically, the NWB position can potentially replace the NCSP as the ideal position for clinical treatment.

How to Define Pediatric Flatfoot: Comparison of 2 Methods: Foot Posture in Static and Dynamic Conditions in Children 5 to 9 Years Old.

Prospective cohort study.

Does foot mobility affect the outcome in the management of patellofemoral pain with foot orthoses versus hip exercises? A randomised clinical trial

ObjectivesTo test (i) if greater foot pronation (measured as midfoot width mobility) is associated with better outcomes with foot orthoses treatment, compared with hip exercises and (ii) if hip exercises...

Foot health and quality of life in patients with rheumatoid arthritis: a cross-sectional study

ObjectiveThe aim of this study is to identify foot health factors related to the quality of life in patients with rheumatoid arthritis (RA).SettingIn this cross-sectional study, a total of 293...

THE EFFECT of KINESIO TAPE® on STATIC FOOT POSTURE, PLANTAR PRESSURE, and REARFOOT MOTION in INDIVIDUALS with PRONATED FEET

Kinesio Tape® (KT) is an elastic therapeutic tape that is applied to the skin for treatment of sport-related injuries. Its application has been purported to facilitate the neuromuscular system, thus altering skeletal muscle activity to increase joint range of motion and improve performance. Due to its proposed therapeutic effect, KT may benefit individuals with excess foot pronation in order to decrease pain and improve function. Unfortunately, current research regarding the ability of KT to alter foot biomechanics is limited. The purpose of this study was to determine if the application of KT to the ankle and lower leg would alter static foot posture, plantar pressure, and foot motion during walking in individuals with foot pronation. Prospective Cohort Study. Thirty participants (10M/20F) were recruited for this study. Each participant had their dorsal arch height and midfoot width measured prior to the application of the KT. In addition, their dynamic rearfoot eversion and plantar pressure was recorded during walking using an electrogoniometer and plantar pressure system. After these measurements were collected, KT was applied to their right foot and lower leg in order to attempt to facilitate activity in the posterior tibialis muscle. After applying the tape, the above measurements were repeated. None of the variables measured were statistically significantly different between the pre-test and post-test. Application of KT did not result in a change in static foot posture, plantar pressure, and frontal plane rearfoot motion during walking. As such, KT cannot be recommended as a treatment for reducing excessive foot pronation where such a goal would be beneficial. Level 3.

Three-dimensional quantitative analysis of healthy foot shape: a proof of concept study

BackgroundFoot morphology has received increasing attention from both biomechanics researches and footwear manufacturers. Usually, the morphology of the foot is quantified by 2D footprints. However, footprint quantification ignores the foot’s vertical dimension and hence, does not allow accurate quantification of complex 3D foot shape.MethodsThe shape variation of healthy 3D feet in a population of 31 adult women and 31 adult men who live in Belgium was studied using geometric morphometric methods. The effect of different factors such as sex, age, shoe size, frequency of sport activity, Body Mass Index (BMI), foot asymmetry, and foot loading on foot shape was investigated. Correlation between these factors and foot shape was examined using multivariate linear regression.ResultsThe complex nature of a foot’s 3D shape leads to high variability in healthy populations. After normalizing for scale, the major axes of variation in foot morphology are (in order of decreasing variance): arch height, combined ball width and inter-toe distance, global foot width, hallux bone orientation (valgus-varus), foot type (e.g. Egyptian, Greek), and midfoot width. These first six modes of variation capture 92.59% of the total shape variation. Higher BMI results in increased ankle width, Achilles tendon width, heel width and a thicker forefoot along the dorsoplantar axis. Age was found to be associated with heel width, Achilles tendon width, toe height and hallux orientation. A bigger shoe size was found to be associated with a narrow Achilles tendon, a hallux varus, a narrow heel, heel expansion along the posterior direction, and a lower arch compared to smaller shoe size. Sex was found to be associated with differences in ankle width, Achilles tendon width, and heel width. Frequency of sport activity was associated with Achilles tendon width and toe height.ConclusionA detailed analysis of the 3D foot shape, allowed by geometric morphometrics, provides insights in foot variations in three dimensions that can not be obtained from 2D footprints. These insights could be applied in various scientific disciplines, including orthotics and shoe design.

Foot and ankle characteristics and dynamic knee valgus in individuals with patellofemoral osteoarthritis

Study designControlled laboratory study; cross-sectional design.BackgroundFoot and ankle characteristics and dynamic knee valgus differ in people with and without patellofemoral (PF) pain. However, it is unknown if these characteristics are evident in people with PF osteoarthritis (OA), compared to pain-free older adults.ObjectivesTo compare foot and ankle mobility, foot posture and dynamic knee valgus, measured as the frontal plane projection angle (FPPA) during single-leg squatting, between individuals with and without PFOA.MethodsFifty-one participants with PFOA (66% women, mean ± SD age 57 ± 10 years, body mass index (BMI) 27 ± 6 kg/m2), and 23 controls (56% women, age 56 ± 9 years, BMI 24 ± 4 kg/m2) had ankle dorsiflexion measured using the knee-to-wall test, foot mobility calculated as the difference in midfoot height or width between non-weightbearing and weightbearing, and static foot posture characterized utilizing the Foot Posture Index. Peak FPPA was determined from video recordings while participants performed 5 single-leg squats. Linear regressions examined between-groups relationships for foot and ankle characteristics and the FPPA.ResultsThe PFOA group had less ankle dorsiflexion (odds ratio 6.7, 95% confidence interval 2.46–18.2), greater midfoot height mobility (5.2, 1.78–15.14) and width mobility (4.3, 1.33–14.39), and greater foot mobility magnitude (8.4, 2.32–30.69) than controls. There was no difference in FPPA (knee valgus angle) between groups (15, 0.63–377.99).ConclusionFoot and ankle characteristics were different in individuals with PFOA compared to control participants, however there was no difference in dynamic knee valgus during single leg squat. Clinical interventions to address greater foot mobility may be relevant for PFOA.

Age-related differences in foot mobility in individuals with patellofemoral pain

BackgroundAge-related changes in midfoot mobility have the potential to influence success with foot orthoses intervention in people with patellofemoral pain (PFP). The aim of this study was to determine whether older people with PFP demonstrate less foot mobility than younger adults with PFP.MethodsOne hundred ninety four participants (113 (58%) women, age 32 ± 7 years, BMI 25 ± 4.9 kg/m2) with PFP (≥ 6 weeks duration) were included, with foot mobility quantified using reliable and valid methods. K-means cluster analysis classified participants into three homogenous groups based on age. After cluster formation, univariate analyses of co-variance (covariates: sex, weight) were used to compare midfoot height mobility, midfoot width mobility, and foot mobility magnitude between age groups (significance level 0.05).ResultsCluster analysis revealed three distinct age groups: 18–29 years (n = 70); 30–39 years (n = 101); and 40–50 years (n = 23). There was a significant main effect for age for midfoot height mobility (p < 0.001) and foot mobility magnitude (p = 0.006). Post-hoc analyses revealed that midfoot height mobility differed across all three groups (moderate to large effect sizes), and that foot mobility magnitude was significantly less in those aged 40–50 years compared to those aged 18–25 years (moderate effect size). There were no significant main effects for age for midfoot width mobility (p > 0.05).ConclusionIndividuals with PFP aged 40–50 years have less foot mobility than younger adults with PFP. These findings may have implications for evaluation and treatment of older individuals with PFP.

Influence of foot posture on the functioning of the windlass mechanism

The absence of a functioning windlass mechanism may delay re-supination of the foot during locomotion and put excess stress on the mid-tarsal joint and soft tissues of the foot. The purpose of this study was to describe the foot posture of individuals that have an impaired or absent windlass mechanism.Forty-seven individuals (34 females and 13 males) with a mean age of 26 years were recruited to participate in this study. The Foot Posture Index was used to visually assess the posture of both feet. In addition, a digital gauge was used to measure dorsal arch height and midfoot width in bilateral resting standing. Dorsal arch height and mid-foot width were also measured in non-weight bearing. Finally, for those individuals without a functioning windlass mechanism, the amount of medial wedging needed to restore its function was measured.Subjects with an “absent” or “impaired” windlass mechanism had a mean Foot Posture Index of +6.8 (sd=2.5) compared to +2.5 (sd=3.1) for those with a functioning windlass mechanism. A series of independent t-tests showed that individuals without a functioning windlass mechanism had a more pronated foot posture, a lower dorsal arch height and a wider mid-foot width compared to those that had a functioning windlass mechanism. Finally, an average medial wedge of 5.1mm (sd=2.1) was able to produce a functioning windlass mechanism in those individuals that previously lacked one.

The Foot Orthoses versus Hip eXercises (FOHX) trial for patellofemoral pain: a protocol for a randomized clinical trial to determine if foot mobility is associated with better outcomes from foot orthoses

BackgroundPatellofemoral pain (PFP) is a prevalent, often recalcitrant and multifactorial knee pain condition. One method to optimize treatment outcome is to tailor treatments to the patient’s presenting characteristics. Foot orthoses and hip exercises are two such treatments for PFP with proven efficacy yet target different ends of the lower limb with different proposed mechanisms of effect. These treatments have not been compared head-to-head, so there is a dearth of evidence for which to use clinically. Only foot orthoses have been explored for identifying patient characteristics that might predict a beneficial effect with either of these two treatments. Preliminary evidence suggests patients will do well with foot orthoses if they have a midfoot width in weight bearing that is ≥ 11 mm more than in non-weight bearing, but this has yet to be verified in a study that includes a comparator treatment and an adequate sample size. This trial will determine if: (i) hip exercises are more efficacious than foot orthoses, and (ii) greater midfoot width mobility will be associated with success with foot orthoses, when compared to hip exercises.MethodsTwo hundred and twenty participants, aged 18–40 years, with a clinical diagnosis of PFP will be randomly allocated with a 1:1 ratio to receive foot orthoses or progressive resisted hip exercises, and stratified into two subgroups based on their presenting midfoot width mobility (high mobility defined as ≥11 mm). The primary outcome will be a 7-point Likert scale for global rating of change. All analyses will be conducted on an intention-to-treat basis using regression models.DiscussionThis trial is designed to compare the efficacy of foot orthoses versus hip exercise, as well as to determine if high midfoot width mobility is associated with better outcomes with foot orthoses when compared to hip exercises. Results of this trial will assist clinicians in optimising the management of those with PFP by testing whether a simple measure of midfoot width mobility can help to determine which patients are most likely to benefit from foot orthoses.Trial registrationThis trial is registered on the Australian New Zealand Clinical Trials Register (ACTRN12614000260628)

The relationship of foot and ankle mobility to the frontal plane projection angle in asymptomatic adults.

BackgroundThe frontal plane projection angle (FPPA) is frequently used as a measure of dynamic knee valgus during functional tasks, such as the single leg squat. Increased dynamic knee valgus is observed in people with knee pathologies including patellofemoral pain and anterior cruciate injury. As the foot is the primary interface with the support surface, foot and ankle mobility may affect the FPPA. This study investigated the relationship between foot and ankle mobility and the FPPA in asymptomatic adults.MethodsThirty healthy people (aged 18–50 years) performed 5 single leg squats. Peak FPPA and FPPA excursion were determined from digital video recordings. Foot mobility was quantified as the difference in dorsal midfoot height or midfoot width, between non-weightbearing and bilateral weightbearing positions. Ankle joint dorsiflexion range was measured as the maximum distance in centimetres between the longest toe and the wall during a knee-to-wall lunge. Linear regressions with generalised estimating equations were used to examine relationships between variables.ResultsHigher midfoot width mobility was associated with greater peak FPPA (β 0.90, p < 0.001, odds ratio [OR] 2.5), and FPPA excursion (β 0.67, p < 0.001, OR 1.9). Lower midfoot height mobility was associated with greater peak FPPA (β 0.37, p = 0.030, OR 1.4) and FPPA excursion (β 0.30, p = 0.020, OR 1.3). Lower ankle joint dorsiflexion was also associated with greater peak FPPA (β 0.61, p = 0.008, OR 1.8) and greater FPPA excursion (β 0.56, p < 0.001, OR 1.7).ConclusionsFoot and ankle mobility was significantly related to the FPPA during the single leg squat in healthy individuals. Specifically, higher midfoot width mobility, or lower ankle joint dorsiflexion range and midfoot height mobility, were associated with a greater FPPA. These foot mobility factors should be considered in the clinical management of knee-related disorders that are associated with a high FPPA.