Associations of foot posture and function to lower extremity pain: results from a population-based foot study

Comparing the efficacy of exercise therapy on adult flexible flatfoot individuals through a network meta-analysis of randomized controlled trials

The aim of this study is to compare the efficacy of different exercise interventions for adult flexible flatfoot. Nine databases (PubMed, EMBASE, Web of Science, the Cochrane Central Register of Controlled Trials (CENTRAL), SCOPUS, PRDro, Google Scholar, China National Knowledge Infrastructure(CNKI) and Wanfang data) were systematically searched from their inception until February 2024. The search resulted in 2112 records, with 11 studies included. All networks revealed low heterogeneity and non-significant inconsistency (I2 ≤ 25.0%). Three network plots were formed for navicular drop. Firstly, compared with the control group, strengthening the posterior tibial muscle + stretching the iliopsoas muscle + TCE (MD: 3.32, 95% CI: 1.78, 4.89), PNF (MD: 1.81, 95%CI: -0.05, 3.70), SFE (MD: 1.23, 95%CI: 1.02, 1.44) all showed better effects. And strengthening the posterior tibial muscle + stretching the iliopsoas muscle + TCE exercise is considered to be the most effective intervention, with SUCRA of 0.97. Secondly, compared with the control group, hip-focused neuromuscular exercise (MD: 6.22, 95% CI: -1.69, 14.12), SFE with EMG biofeedback (MD: -0.81, 95%CI: -1.59, 3.21) all showed better effects. And hip-focused neuromuscular exercise is considered to be the most effective intervention, with SUCRA of 0.92. Thirdly, the internal foot muscle training combined with gluteus muscle strengthening is significantly better than the other two groups, with SUCRA of 0.99. For the foot posture index, comprehensive reinforcement (MD: 1.95, 95% CI - 0.19, 4.03) showed better effects compared with the control group. In the probability ranking table, comprehensive reinforcement is significantly better than the other two groups, with SUCRA of 0.98. For the foot function index, orthoses wear + stretching + eccentric progressive resistive exercise of tibialis posterior is significantly better than the other two groups, with SUCRA of 0.92. In conclusion, various exercise therapies improve the arch shape and function of patients with flexible flatfoot, particularly hip muscle and lower limb overall muscle training.

Three-dimensional gait analysis of orthopaedic common foot and ankle joint diseases

Walking is an indispensable mode of transportation for human survival. Gait is a characteristic of walking. In the clinic, patients with different diseases exhibit different gait characteristics. Gait analysis describes the specific situation of human gait abnormalities by observing and studying the kinematics and dynamics of limbs and joints during human walking and depicting the corresponding geometric curves and values. In foot and ankle diseases, gait analysis can evaluate the degree and nature of gait abnormalities in patients and provide an important basis for the diagnosis of patients' diseases, the correction of abnormal gait and related treatment methods. This article reviews the relevant literature, expounds on the clinical consensus on gait, and summarizes the gait characteristics of patients with common ankle and foot diseases. Starting from the gait characteristics of individuals with different diseases, we hope to provide support and reference for the diagnosis, treatment and rehabilitation of clinically related diseases.

Human foot form and function: variable and versatile, yet sufficiently related to predict function from form

The human foot is a complex structure that plays an important role in our capacity for upright locomotion. Comparisons of our feet with those of our closest extinct and extant relatives have linked shape features (e.g. the longitudinal and transverse arches, heel size and toe length) to specific mechanical functions. However, foot shape varies widely across the human population, so it remains unclear if and how specific shape variants are related to locomotor mechanics. Here we constructed a statistical shape-function model (SFM) from 100 healthy participants to directly explore the relationship between the shape and function of our feet. We also examined if we could predict the joint motion and moments occurring within a person's foot during locomotion based purely on shape features. The SFM revealed that the longitudinal and transverse arches, relative foot proportions and toe shape along with their associated joint mechanics were most variable. However, each of these only accounted for small proportions of the overall variation in shape, deformation and joint mechanics, most likely owing to the high structural complexity of the foot. Nevertheless, a leave-one-out analysis showed that the SFM can accurately predict joint mechanics of a novel foot, based on its shape and deformation.

Comparing the effects of University of California Biomechanics Laboratory and custom-made semi-rigid insole on pedobarographic parameters in pediatric flexible flat foot

BACKGROUND

Pediatric flexible flat foot (PFFF) is often associated with pain along the medial longitudinal arch and potential disability. There are several conservative treatment options for PFFF, ranging from intrinsic muscle exercises to orthosis, including University of California Biomechanics Laboratory (UCBL) and custom-made semi-rigid insoles.

OBJECTIVES

To investigate and compare the effect of UCBL and custom-made semi-rigid insoles on pedobarographic and radiologic parameters in PFFF.

STUDY DESIGN

This study prepared a retrospective chart review of 143 children diagnosed with PFFF between the age of 4 and 12 years.

METHODS

Data of twenty-seven children with PFFF who were prescribed foot orthoses between the age of 4 and 12 years were retrospectively reviewed. Medical charts were retrospectively reviewed, and pedobarographic and radiological parameters assessed before and 1 year after application of orthoses were reviewed.

RESULTS

The difference in the calcaneal pitch angle and the center of pressure excursion index (CPEI) were significantly improved in the custom-made semi-rigid insole group compared to that in the UCBL group. The contact area ratio of the midfoot and toe and CPEI at 1 year after wearing the insole was significantly improved in the custom-made semi-rigid insole group compared to that in the UCBL group. Moreover, the calcaneal pitch angle and CPEI were significantly improved 1 year after application of the insole in the custom-made semi-rigid insole group.

CONCLUSIONS

This result showed that the custom-made semi-rigid insole is more effective in improving the deviation of the center pressure curve and calcaneal pitch angle than the UCBL. The custom-made semi-rigid insole may help relieve foot instability during gait and improve the medial longitudinal arch in children with PFFF.

Effects of foot orthoses and footwear interventions on impairments and quality of life in people with hip pain: A systematic review

BACKGROUND

Foot orthoses and footwear interventions are advocated for the management of lower limb musculoskeletal conditions including the hip, but much of the research is focused on knee disorders. The aim of this systematic review was to synthesise the literature that investigates the use of foot orthoses or footwear in people with hip-related pain.

METHODS

MEDLINE, EMBASE, CINAHL, AMED and SPORTDiscus were searched from inception to March 2023. Randomised controlled trials (RCT), cohort and pre-post studies reporting on footwear and foot orthoses interventions, in participants with hip-related pain, were eligible for inclusion. Outcomes included pain, physical function, and quality of life (QoL). Effect sizes were calculated where sufficient data were available. Reporting quality was assessed using the Cochrane Risk of Bias Tool (Rob-2) and the Joanna Briggs Institute Checklist. The overall quality of evidence was rated according to the Grading of Recommendations, Assessment, Development, and Evaluations framework.

RESULTS

Of the seven included studies (n = 266 participants), there was one RCT, one cohort and five single-group pre-post designs. Interventions included customised and non-customised arch supports, heel lifts, and footwear modifications, used in the following hip conditions: trochanteric pain, non-specific hip pain, hip osteoarthritis, and leg length dysfunction following total hip arthroplasty. Meta-analysis was possible for outcomes in two studies, demonstrating moderate improvement in pain following foot orthoses use. Overall certainty of evidence ranged from very low to low.

CONCLUSION

Single-group pre-post study designs describe positive relationships between foot orthoses and footwear use and improvements in hip pain, function, and QoL. However, these results were not supported by the only available RCT. Given this is a relatively inexpensive and non-invasive treatment approach, further rigorous studies are warranted.

Gluteus medius muscle strengthening exercise effects on medial longitudinal arch height in individuals with flexible flatfoot: a randomized controlled trial

This study aimed to compare the effects of 8 weeks of foot plus hip exercise to foot exercise alone on medial longitudinal arch (MLA) parameters; navicular drop (ND), arch height index (AHI), plantar pressure, static balance, and dynamic balance were measured at baseline, 4 weeks, and 8 weeks. A total of 52 healthy participants with bilateral flatfoot were randomly assigned into foot exercise (n=26) and foot plus hip exercise (n=26) group. At 4 weeks, the foot plus hip exercise group showed significantly less ND (P=0.002), plantar pressure at the medial forefoot (P=0.002), and mediolateral displacement (P=0.001) while showing a greater AHI (P=0.019) than the foot exercise group. At 8 weeks, there was also significantly less plantar pressure at the medial hindfoot (P=0.017) and less anteroposterior displacement (P=0.002) in the foot plus hip exercise group than in the foot exercise group. No significant differences between groups were found in dynamic balance. The addition of gluteus medius muscle strengthening exercise to foot exercise was more effective in supporting the MLA than performing foot exercise alone.

Do posted foot orthoses alter hip biomechanics and pain during walking in women with greater trochanteric pain syndrome?

BACKGROUND

Greater trochanteric pain syndrome (GTPS), including gluteal tendinopathy and bursitis, is a common, painful and debilitating condition. It is thought to involve overload of the gluteal tendons, which may be amplified through increased hip adduction moment (HAM) seen during gait in these individuals. Reducing the aberrant HAM may improve pain and function in this population. We aimed to determine if medially-posted foot orthoses immediately reduce HAM and pain in females with GTPS during walking gait.

METHODS

A double-blind, repeated-measures trial with randomised intervention order compared three conditions in 53 women with GTPS. Participants acted as their own control during baseline (everyday-shoe insole), medially-posted (active) orthosis, or flat insert (sham orthosis) walking. Data were collected via three-dimensional gait analysis for HAM, hip, pelvic, and thorax kinematics; as well as ground reaction force; and pain via the numerical rating scale. Subgroup analysis was performed based on a pronated foot-posture defined by the Foot Posture Index.

RESULTS

A small pain reduction was found between the active orthosis and flat insert (mean difference = -0.444, p = 0.017). No difference was detected for pain between other condition comparisons. Thoracic lateral flexion increased at second-peak HAM between the baseline and active conditions (mean difference = -0.917, p = 0.040). No differences were detected for HAM, remaining kinematic or kinetic variables, or ground reaction force data across the three conditions. No significant differences were detected between any of the three conditions for biomechanical or pain data in the pronated-foot subgroup.

SIGNIFICANCE

A medially-posted foot orthosis did not immediately alter gait biomechanics or provide a clinically meaningful pain reduction in women with GTPS. There is uncertainty regarding the clinical benefit of orthoses in the management of GTPS. Longer-term follow-up or the use of customised orthoses may produce different outcomes and should be explored in future research.

Toward improved understanding of foot shape, foot posture, and foot biomechanics during running: A narrative review

The current narrative review has explored known associations between foot shape, foot posture, and foot conditions during running. The artificial intelligence was found to be a useful metric of foot posture but was less useful in developing and obese individuals. Care should be taken when using the foot posture index to associate pronation with injury risk, and the Achilles tendon and longitudinal arch angles are required to elucidate the risk. The statistical shape modeling (SSM) may derive learnt information from population-based inference and fill in missing data from personalized information. Bone shapes and tissue morphology have been associated with pathology, gender, age, and height and may develop rapid population-specific foot classifiers. Based on this review, future studies are suggested for 1) tracking the internal multi-segmental foot motion and mapping the biplanar 2D motion to 3D shape motion using the SSM; 2) implementing multivariate machine learning or convolutional neural network to address nonlinear correlations in foot mechanics with shape or posture; 3) standardizing wearable data for rapid prediction of instant mechanics, load accumulation, injury risks and adaptation in foot tissue and bones, and correlation with shapes; 4) analyzing dynamic shape and posture via marker-less and real-time techniques under real-life scenarios for precise evaluation of clinical foot conditions and performance-fit footwear development.

A Strong Correlation Between the Severity of Flatfoot and Symptoms of Knee Osteoarthritis in 95 Patients

Objective

The purpose of this study is to assess the association between the presence and severity of flatfoot and symptoms of knee OA.

Methods

95 participants with knee OA were recruited from a patient cohort at a regional hospital. Symptoms of knee OA, including knee degeneration, femorotibial alignment, pain, stiffness and dysfunction were assessed using the Kellgren-Lawrence (K-L) grading system, femoral-tibial angle (FTA), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Participants were divided into groups with flatfoot (mild, moderate and severe) and without flatfoot based on the Clarke's angle. Linear regression and ordinal logistic regression were used for statistical analysis, as appropriate.

Results

Having flatfoot was associated with a significantly increased risk of having a higher K-L grade (OR: 20.03; 95% CI, 5.88, 68.27; p < 0.001), smaller FTA (Beta: −2.96; 95% CI, −4.41, −1.50; p < 0.001), higher pain score (Beta: 0.47; 95% CI, 0.24, 0.69; p < 0.001) and greater loss of function (Beta: 0.25; 95% CI, 0.02, 0.48; p = 0.03). Severe grades of flat feet were associated with a higher K-L grade (OR: 0.19; 95% CI, 0.08, 0.44; p < 0.001), smaller FTA (Beta: 1.51; 95% CI, 0.66, 2.35; p = 0.001), higher pain score (Beta: −0.25; 95% CI, −0.39, −0.11; p = 0.001), greater stiffness (Beta: −0.24; 95% CI, −0.38, −0.09; p = 0.002) and greater loss of function (Beta: −0.27; 95% CI, −0.41, −0.14; p < 0.001).

Conclusion

The results indicated that the severity of flattening is significantly associated with symptoms of knee OA. For the conservative management of knee OA, both flatfoot and its severity should be carefully considered.

Is there a relationship between lower-extremity injuries and foot postures in professional football players? A prospective cohort study

BACKGROUND

Lower extremity injuries are an ongoing concern for professional football players. This study aims to evaluate the relationship between foot posture and lower extremity injuries in professional football players.

METHOD

In this prospective cohort study, 420 male players of the Iran Premium football league were evaluated during the 2015-2016 season. The players were assessed for their foot types based on optical and static foot scans and foot posture index (FPI). The trained club physicians recorded all injuries during the season.

RESULT

The analyzed data of 244 players showed the highest rate of lower extremity injury in hamstrings, ankle, and groin, respectively. These injuries led to 46% of time loss. The probability of hamstrings injuries was higher among pronated players based on static, optic, FPI, and visual examination, 2.1, 1.8, 1.8, and 2.3, respectively. Medial Collateral Ligament (MCL) injuries were associated with subtalar joint abnormality defined by visual observation. An increased relative risk of leading-to-absence injuries among the flat foot group was significant based on optic scanning, FPI, and visual observation.

CONCLUSION

Abnormal foot postures in professional football players may increase the risk of hamstring and MCL injuries and time loss due to lower extremity injuries.

Immediate comfort perception of 3D-printed foot orthoses in individuals with unilateral heel pain

BACKGROUND

Custom-made foot orthoses (FOs) play an integral part in managing foot disorders. Traditional FO fabrication is time-consuming and labor intensive. Three-dimensional (3D) printed FOs save time and cost compared with the traditional manufacturing process. To date, the differences in dimensions and comfort perception of these orthoses have not been compared in a pathological population.

OBJECTIVE

Compare the dimensions between 3D-printed and traditionally made FOs and comfort perception between 3D-printed, traditionally made, and no FOs in individuals with flatfeet and unilateral heel pain.

STUDY DESIGN

Within-subject single-blinded randomized crossover study design.

METHODS

Thirteen participants had custom-made FOs using 3D-printing and traditional processes. Orthotic lengths, widths, arch heights, and heel cup heights were compared. Participants performed walking trials under three conditions: (1) no orthoses, (2) 3D-printed orthoses, and (3) traditionally made orthoses. Comfort perception was recorded. Orthotic dimensions were compared using paired t tests, and comfort perception were compared using one-way multiple analysis of variance and Bonferroni post hoc tests.

RESULTS

Three-dimensional-printed orthoses were wider, have higher arch heights, and heel cup heights compared with traditionally made FOs (medium to large effect sizes). There was a difference in comfort perception between the three orthotic conditions, F(12,62) = 1.99, P = 0.04; Wilk Λ = 0.521, ηp2= 0.279. Post hoc tests show that there is no difference in comfort perception between the 3D-printed and traditionally made FOs. Both FOs were significantly more comfortable than no orthoses.

CONCLUSIONS

Three-dimensional printing seems to be a viable alternative orthotic fabrication option. Future studies should compare the biomechanical effects of 3D-printed and traditionally made FOs.

Mechanobiology and Adaptive Plasticity Theory as a Potential Confounding Factor in Predicting Musculoskeletal Foot Function

There are many theoretical models that attempt to accurately and consistently link kinematic and kinetic information to musculoskeletal pain and deformity of the foot. Biomechanical theory of the foot lacks a consensual model: clinicians are enticed to draw from numerous paradigms, each having different levels of supportive evidence and contrasting methods of evaluation, in order to engage in clinical deduction and treatment planning. Contriving to find a link between form and function lies at the heart of most of these competing theories and the physical nature of the discipline has prompted an engineering approach. Physics is of great importance in biology and helps us to model the forces that the foot has to deal with in order for it to work effectively. However, the tissues of the body have complex processes that are in place to protect them and they are variable between individuals. Research is uncovering why these differences exist and how these processes are governed. The emerging explanations for adaptability of foot structure and musculoskeletal homeostasis offer new insights into how clinical variation in outcomes and treatment effects might arise. These biological processes underlie how variation in the performance and use of common traits, even within apparently similar subgroups, make anatomical distinction less meaningful and are likely to undermine the justification of a "foot type." Furthermore, mechanobiology introduces a probabilistic element to morphology based on genetic and epigenetic factors.

ISB recommendations for skin-marker-based multi-segment foot kinematics

The foot is anatomically and functionally complex, and thus an accurate description of intrinsic kinematics for clinical or sports applications requires multiple segments. This has led to the development of many multi-segment foot models for both kinematic and kinetic analyses. These models differ in the number of segments analyzed, bony landmarks identified, required marker set, defined anatomical axes and frames, the convention used to calculate joint rotations and the determination of neutral positions or other offsets from neutral. Many of these models lack validation. The terminology used is inconsistent and frequently confusing. Biomechanical and clinical studies using these models should use established references and describe how results are obtained and reported. The International Society of Biomechanics has previously published proposals for standards regarding kinematic and kinetic measurements in biomechanical research, and in this paper also addresses multi-segment foot kinematics modeling. The scope of this work is not to prescribe a particular set of standard definitions to be used in all applications, but rather to recommend a set of standards for collecting, calculating and reporting relevant data. The present paper includes recommendations for the overall modeling and grouping of the foot bones, for defining landmarks and other anatomical references, for addressing the many experimental issues in motion data collection, for analysing and reporting relevant results and finally for designing clinical and biomechanical studies in large populations by selecting the most suitable protocol for the specific application. These recommendations should also be applied when writing manuscripts and abstracts.

Influence of the medial longitudinal arch of the foot in adult women in ankle isokinetic performance: a cross-sectional study

BACKGROUND

Maintenance of the medial longitudinal arch (MLA) of the foot is fundamental during functional tasks and disorders can lead to clinical alterations. Studies have demonstrated that deficits in ankle isokinetic performance can predispose an individual to lower limb injuries.

OBJECTIVES

To evaluate the muscular performance of cavus, planus, and normal feet by means of torque/body mass and the isokinetic phases, to generate 3D surface map analysis, and to verify whether there is a relationship between MLA height and arch height flexibility with isokinetic performance.

METHODS

The sample consisted of 105 healthy adult women, divided into three groups: normal, cavus, and planus. Assessment in concentric mode at 30, 60, and 90 °/s in the dorsiflexion and plantarflexion of the ankle joint were analyzed during the three isokinetic phases (acceleration, sustained velocity, and deceleration). The variables total range of motion, peak of torque (PT), and angle of PT were extracted within the sustained velocity.

RESULTS

In dorsiflexion at 60 °/s, the phase where the velocicty is sustained (load range phase) was higher in the planus group (M_eanD_ifference=10.9 %; ω²_p = 0.06) when compared with the cavus group. Deficits in the peak torque/body mass in dorsiflexion at 60 °/s (cavus feet: MD=-3 N.m/kg; ω²_p = 0.06; and planus feet: MD=-1.1 N.m/kg; ω²_p = 0.06) were also observed as well as in the 3D surface maps, when compared with the normal group. The flexibility of MLA had a negative correlation of PT at 30 °/s in cavus group. The heigth of MLA had a postive correlation with the PT for the cavus and planus group ate 60 °/s. All other results did not show differences between the groups.

CONCLUSIONS

The planus groups showed a better capacity of attain and sustained the velocity in dorsiflexion in relation the cavus group. The cavus and planus group had deficts in torque in relation the normal. The correlations were weak between the measures of MLA and PT. Thereby, in general the differences between foot types showed small effect in isokinetic muscle performance measures of the plantar and dorsi flexores.

TRIAL REGISTRATION

Study design was approved by the IRB (#90238618.8.0000.5231).

Anti-pronator components are essential to effectively alter lower-limb kinematics and kinetics in individuals with flexible flatfeet

BACKGROUND

Foot orthoses are commonly used to correct for foot alterations and especially address excessive foot pronation in individuals with flatfeet. In recent years, 3D printing has taken a key place in orthotic manufacturing processes as it offers more options and can be patient specific. Hence, the purpose of this study was to evaluate whether stiffness of 3D printed foot orthoses and a newly designed rearfoot posting have an effect on lower limb kinematics and kinetics in individuals with flatfeet.

METHODS

Nineteen patients with flexible flatfeet were provided two pairs of customized 3D printed ¾ length orthotics. Foot orthoses were of different stiffness and could feature a rearfoot posting, consisting of 2-mm carbon fiber plate. Lower limb kinematics and kinetics were computed using a multi-segment foot model. One-way ANOVAs using statistical non-parametric mapping, refined by effect sizes, were performed to determine the magnitude of the effect between conditions.

FINDINGS

Foot orthoses stiffness had little effect on midfoot and forefoot biomechanics. Reductions in midfoot eversion and forefoot abduction were observed during short periods of stance with rigid foot orthoses. Adding the posting had notable effects on rearfoot kinematics and on the ankle and knee kinetics in the frontal plane; it significantly reduced the eversion angle and inversion moment at the ankle, and increased the knee abduction moment.

INTERPRETATION

Using an anti-pronator component is more effective than increasing foot orthoses stiffness to observe a beneficial impact of foot orthoses on the control of excessive foot pronation in individuals with flatfeet.

Quantifying lower limb inter-joint coordination and coordination variability after four-month wearing arch support foot orthoses in children with flexible flat feet

INTRODUCTION

Flat feet in children negatively affect lower limb alignment and cause adverse health-related problems. The long-term application of foot orthoses (FOs) may have the potential to improve lower limb coordination and its variability.

AIM

To evaluate the effects of long-term use of arch support FOs on inter-joint coordination and coordination variability in children with flexible flat feet.

METHODS

Thirty boys with flexible flat feet were randomly assigned to the experimental (EG) and control groups. The EG used medial arch support FOs during daily activities over a four-month period while the control group received a flat 2-mm-thick insole for the same time period. Lower-limb coordination and variability during the 3 sub-stance phases were quantified using a vector coding technique.

RESULTS

Frontal plane ankle-hip coordination in EG during mid-stance changed to an anti-phase pattern (156.9^°) in the post-test compared to an in-phase (221.1^°) in the pre-test of EG and post-test of CG (222.7). Frontal plane knee-hip coordination in EG during loading response (LR) changed to an anti-phase pattern (116^°) in the post-test compared to an in-phase (35.5^°) in the pre-test of EG and post-test of CG (35.3). Ankle inversion/eversion-knee internal/external rotation joint coupling angle in EG changed to an in-phase pattern (59^°) in the post-test compared to a proximal phase (89^°) in the pre-test. Coupling angle variability increased in the post-test of EG for sagittal plane ankle-hip during push-off, transverse plane ankle-hip during LR and mid-stance, and transverse plane knee-hip during LR and mid-stance compared to pre-test of EG and post-test of CG.

CONCLUSION

The long-term use of arch support FOs proved to be effective to alter lower limb coordination and coordination variability during walking in children with flexible flat feet. This new insight into coordinative function may be useful for improving corrective exercise strategies planned for children with flat feet.

Immediate Effects of Medially Posted Insoles on Lower Limb Joint Contact Forces in Adult Acquired Flatfoot: A Pilot Study

Flatfoot is linked to secondary lower limb joint problems, such as patellofemoral pain. This study aimed to investigate the influence of medial posting insoles on the joint mechanics of the lower extremity in adults with flatfoot. Gait analysis was performed on fifteen young adults with flatfoot under two conditions: walking with shoes and foot orthoses (WSFO), and walking with shoes (WS) in random order. The data collected by a vicon system were used to drive the musculoskeletal model to estimate the hip, patellofemoral, ankle, medial and lateral tibiofemoral joint contact forces. The joint contact forces in WSFO and WS conditions were compared. Compared to the WS group, the second peak patellofemoral contact force (p < 0.05) and the peak ankle contact force (p < 0.05) were significantly lower in the WSFO group by 10.2% and 6.8%, respectively. The foot orthosis significantly reduced the peak ankle eversion angle (p < 0.05) and ankle eversion moment (p < 0.05); however, the peak knee adduction moment increased (p < 0.05). The reduction in the patellofemoral joint force and ankle contact force could potentially inhibit flatfoot-induced lower limb joint problems, despite a greater knee adduction moment.

A Long-term Follow-up of Young Adults With Idiopathic Clubfoot: Does Foot Morphology Relate to Pain?

BACKGROUND

Individuals with clubfoot, treated in infancy with either the Ponseti method or comprehensive clubfoot release, often encounter pain as adults. Multiple studies have characterized residual deformity after Ponseti or surgical correction using physical exam, radiographs and pedobarography; however, the relationship between residual foot deformity and pain is not well defined. The purpose of the current study was 2-fold: (1) to evaluate the relationship between foot morphology and pain for young adults treated as infants for idiopathic clubfoot and (2) to describe and compare pedobarographic measures and outcome measures of pain and morphology among surgically treated, Ponseti treated, and typically developing feet.

METHODS

We performed a case-control study of individuals treated for clubfoot at 2 separate institutions with either the Ponseti method or comprehensive clubfoot release between 1983 and 1987. All subjects (24 treated with comprehensive clubfoot release, 18 with Ponseti method, and 48 controls) were evaluated using the International Clubfoot Study Group (ICFSG) morphology scoring, dynamic pedobarography, and foot function index surveys. During pedobarography, we collected the subarch angle and arch index as well as the center of pressure progression (COPP) on all subjects.

RESULTS

Foot morphology (ICFSG) scores were highly correlated with foot function index pain scores (r=0.43; P<0.001), although the difference in pain scores between the surgical and Ponseti group did not reach significance. The surgical group exhibited greater subarch angle and arch indexes than the Ponseti group, demonstrating a significant difference in morphology, a flatter foot. Finally, we found more abnormalities in foot progression, decreased COPP in the forefoot and increased COPP in the midfoot and hindfoot, in the surgical group compared with controls.

CONCLUSIONS

Measures of foot morphology were correlated with pain among all treated for clubfoot. Compared with Ponseti method, comprehensive surgical release lead to greater long-term foot deformity, flatter feet and greater hindfoot loading time.

LEVEL OF EVIDENCE

Level III-Therapeutic.

Center of pressure limb path differences for the detection of lameness in dogs: a preliminary study

Background

The limb center of pressure (COP) path measures and quantifies the load distribution within a limb in a still or moving subject. Under this premise, the aim of this study was to test whether data derived from this parameter could detect the differences between sound and lame limbs in unilaterally lame dogs with elbow dysplasia.

To accomplish this purpose, ten unilaterally lame dogs of similar conformation were walked over a pressure platform. Next, the COP path, in relation to the position of sound and lame limbs, was measured in a coordinate system over a standard paw template obtained by pedobarography during the whole support phase. To compare variables, force platform data (peak vertical force and vertical impulse) from the same animals were obtained. Sound and lame limb statokinesiograms were also obtained while the animals stood still.

Results

The statistical analysis clearly showed that COP in lame limbs start cranially and were shorter than sound limbs. In addition, the value of the COP excursion index was lower in lame limbs. Finally, the area of statokinesiograms was greater in lame limbs.

Conclusion

This methodology based in limb COP characteristics serves to discriminate between sound and lame limbs in dogs with elbow dysplasia.

Electronic supplementary material

The online version of this article (10.1186/s12917-019-1881-1) contains supplementary material, which is available to authorized users.

Ultrasound evaluation of the quadriceps muscles in pronated foot posture

OBJECTIVE

The main goal of this study was to investigate the size of all portions of the quadriceps muscles in individuals with pronated foot posture compared to normal foot posture using ultrasound imaging.

DESIGN

Twenty nine females with pronated foot posture and 29 age-, body weight-, body height-matched females with normal foot posture were recruited from university communities. The muscle thicknesses of the rectus femoris (RF), vastus medialis (VM), vastus medialis oblique (VMO), vastus lateralis (VL) and vastus intermedius (VI) were measured using ultrasound imaging.

RESULTS

The thicknesses of the RF and VMO were significantly smaller in individuals with pronated foot posture compared to normal foot posture (p<0.05). No significant differences were observed in the VM, VL, and VI muscle thicknesses in both groups.

CONCLUSION

Based on the results of the present study, it seems that besides the foot and lower leg muscles, an integrated assessment of proximal knee muscles, especially quadriceps, is required in individuals with pronated foot posture.

Centre of pressure characteristics during walking in individuals with and without first metatarsophalangeal joint osteoarthritis

OBJECTIVE

The objective of this study was to compare centre of pressure characteristics during walking in individuals with and without first metatarsophalangeal joint osteoarthritis (1st MTPJ OA), in order to provide insights into alterations in foot function associated with this condition.

METHODS

Twenty people with 1st MTPJ OA and 20 asymptomatic controls matched for age, sex and body mass index underwent gait analysis using the emed^®-x400 plantar pressure system (Novel GmbH, Germany). Average and maximum centre of pressure velocity and lateral-medial force index during loading, midstance, terminal stance and preswing were compared between the groups.

RESULTS

During the preswing phase of gait, maximum centre of pressure velocity was significantly slower in individuals with 1st MTPJ OA (0.78 ± 0.19 vs 1.13 ± 0.36 m/sec; p = 0.003), and both average and maximum lateral-medial force indices were significantly higher in individuals with 1st MTPJ OA (0.98 ± 0.14 vs 0.82 ± 0.13; p < 0.001 and 1.37 ± 0.29 vs 1.15 ± 0.15; p = 0.008, respectively). Non-weightbearing 1st MTPJ dorsiflexion range of motion was significantly associated with maximum centre of pressure velocity (r = 0.54, p < 0.001) and average lateral-medial force index (r = -0.44, p = 0.004) during preswing.

CONCLUSIONS

Individuals with 1st MTPJ OA exhibit significant differences in centre of pressure characteristics during propulsion, possibly due to decreased range of available 1st MTPJ dorsiflexion.

Concurrent validity of an automated algorithm for computing the center of pressure excursion index (CPEI)

Center of Pressure Excursion Index (CPEI), a parameter computed from the distribution of plantar pressures during stance phase of barefoot walking, has been used to assess dynamic foot function. The original custom program developed to calculate CPEI required the oversight of a user who could manually correct for certain exceptions to the computational rules. A new fully automatic program has been developed to calculate CPEI with an algorithm that accounts for these exceptions. The purpose of this paper is to compare resulting CPEI values computed by these two programs on plantar pressure data from both asymptomatic and pathologic subjects. If comparable, the new program offers significant benefits-reduced potential for variability due to rater discretion and faster CPEI calculation. CPEI values were calculated from barefoot plantar pressure distributions during comfortable paced walking on 61 healthy asymptomatic adults, 19 diabetic adults with moderate hallux valgus, and 13 adults with mild hallux valgus. Right foot data for each subject was analyzed with linear regression and a Bland-Altman plot. The automated algorithm yielded CPEI values that were linearly related to the original program (R²=0.99; P<0.001). Bland-Altman analysis demonstrated a difference of 0.55% between CPEI computation methods. Results of this analysis suggest that the new automated algorithm may be used to calculate CPEI on both healthy and pathologic feet.

A foot-care program to facilitate self-care by the elderly: a non-randomized intervention study

OBJECTIVE

We aimed to evaluate a foot-care awareness program designed to improve foot morphology, physical functioning, and fall prevention among the community-dwelling elderly. Eleven independent community-dwelling elderly women (aged 61-83 years) were provided with foot-care advice and shown effective foot-care techniques to perform regularly for 6 months, and compared with a control group of 10 elderly women who did not receive any intervention. Measurements of foot form, functional capacity, subjective foot movement, and physical function were taken at baseline and 6-month follow-up.

RESULTS

At follow-up, improvements were seen in the intervention group in foot morphology, subjective foot movement, foot pressure, and balance. In the intervention group, 90% of women had maintained or improved foot form and none of them had fallen during the post-intervention period, compared to the control group where 30% improved foot form (p = 0.0075) and four (40%) of them had fallen. Therefore, a foot-care program may have the potential to prevent falls and improve mobility among the elderly. Trial Registration UMIN-CTR No. UMIN000029632. Date of Registration: October 19, 2017.

Link Between Foot Pain Severity and Prevalence of Depressive Symptoms

OBJECTIVE

Associations between pain and depression are well known, yet foot pain, common in populations, has been understudied. This cross-sectional study examined foot pain and severity of foot pain with depressive symptoms in adults.

METHODS

Framingham Foot Study (2002-2008) participants completed questionnaires that included questions about foot pain (yes/no; none, mild, moderate, or severe pain) and the Center for Epidemiologic Studies Depression Scale (scores ≥16 indicated depressive symptoms). Age and body mass index (BMI) were also assessed. Sex-specific logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations of foot pain with depressive symptoms, adjusting for age and BMI. In a subset, further models adjusted for leg pain, back pain, or other joint pain.

RESULTS

Of 1,464 men and 1,857 women, the mean ± SD age was 66 ± 10 years. Depressive symptoms were reported in 21% of men and 27% of women. Compared to those with no foot pain and independent of age and BMI, both men and women with moderate foot pain had approximately a 2-fold increased odds of depressive symptoms (men with severe foot pain OR of 4 [95% CI 2.26-8.48], women with severe foot pain OR of 3 [95% CI 2.02-4.68]). Considering other pain regions attenuated ORs, but the pattern of results remained unchanged.

CONCLUSION

Even after we adjusted for age, BMI, and other regions of pain, those reporting worse foot pain were more likely to report depressive symptoms. These findings suggest that foot pain may be a part of a broader pain spectrum, with an impact beyond localized pain and discomfort.

Effect of foot orthoses on the medial longitudinal arch in children with flexible flatfoot deformity: A three-dimensional moment analysis

Foot orthoses are often used to correct altered gait patterns. The purpose of this study was to investigate how foot orthoses can modify the magnitude of three dimensional moments of ankle, knee, and hip joints during a stride of gait in children with flexible flat feet. Bilateral gait data were collected from fourteen male children (age 10.2±1.4 years) suffering from flat feet syndrome. In order to obtain the kinematics data, a Vicon system with six cameras (100Hz) was used and two Kistler force plates (1000Hz) to record the kinetics data under each leg. Arc support foot orthoses were used as an intervention. Paired-sample T-test was used for within-group comparisons (α=0.05). The results of data analysis showed that foot orthoses can decrease the ankle evertor moment, knee and hip abductor moments and hip flexor moment in dominant lower limb. In non-dominant lower limb, using the orthoses can decrease evertor and internal rotator moments at the ankle, flexor and internal rotator moments at the knee and extensor moment at the hip, while it can increase dorsiflexor moment at the ankle. The findings imply that effects of orthoses on three dimensional moments differ in dominant and non-dominant lower limbs. Furthermore, results demonstrated that dominant and non-dominant lower limbs would also show different responses to the same intervention.

Foot Function, Foot Pain, and Falls in Older Adults: The Framingham Foot Study

BACKGROUND

Although foot pain has been linked to fall risk, contributions of pain severity, foot posture, or foot function are unclear. These factors were examined in a cohort of older adults.

OBJECTIVE

The purpose of this study was to examine the associations of foot pain, severity of foot pain, and measures of foot posture and dynamic foot function with reported falls in a large, well-described cohort of older adults from the Framingham Foot Study.

METHODS

Foot pain, posture, and function were collected from Framingham Foot Study participants who were queried about falls over the past year (0, 1, and ≥2 falls). Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the relation of falls with foot pain, pain severity, foot posture, and foot function adjusting for covariates.

RESULTS

The mean age of the 1,375 participants was 69 years; 57% were female, and 21% reported foot pain (40% mild pain, 47% moderate pain, and 13% severe pain). One-third reported falls in the past year (1 fall: n = 263, ≥2 falls: n = 152). Foot pain was associated with a 62% increased odds of recurrent falls. Those with moderate and severe foot pain showed increased odds of ≥2 falls (OR 1.78, CI 1.06-2.99, and OR 3.25, CI 1.65-7.48, respectively) compared to those with no foot pain. Foot function was not associated with falls. Compared to normal foot posture, those with planus foot posture had 78% higher odds of ≥2 falls.

CONCLUSION

Higher odds of recurrent falls were observed in individuals with foot pain, especially severe foot pain, as well as in individuals with planus foot posture, indicating that both foot pain and foot posture may play a role in increasing the risk of falls among older adults.

Evaluation of foot static disturbances in patients with rheumatic diseases

Objectives

Rheumatic diseases such as osteoarthritis and rheumatoid arthritis constitute the most frequent pathological states leading to the development of foot deformities, which reduce quality of life and cause disability. The aim of the present study was to compare the results of plantoconturographic examinations, obtained by means of a computer podoscope, in osteoarthritis and rheumatoid arthritis patients. Special attention was paid to the differences in the values of each parameter determining the level of foot function.

Material and methods

The study was performed in 94 female patients divided into two groups according to the type of disease. There were 54 patients with rheumatoid arthritis and 40 with osteoarthritis. The control group consisted of 34 healthy women. The plantographic assessment of static foot structure was carried out by means of a device for computer-aided foot examination.

Results

A fallen transverse arch of the right foot was statistically much more frequent in the rheumatoid arthritis patients than in osteoarthritis patients or the control group (p < 0.005 and p < 0.05, respectively). Significant differences in the values of the Wejsflog index were observed in the case of left foot between rheumatoid arthritis patients and the control group (p < 0.05). Similarly, there were statistically significant differences in the values of the hallux valgus angle (α) for the right foot between rheumatoid arthritis and osteoarthritis patients or control group (in both cases p < 0.05).

Conclusions

Rheumatic diseases predispose patients to disturbances of static foot function. The obtained results highlight the importance of diagnosing foot static disturbances in the prevention of destructive changes affecting the functioning of osteoarthritis and rheumatoid arthritis patients.

The effect of foot orthoses on joint moment asymmetry in male children with flexible flat feet

INTRODUCTION

It has been widely postulated that structural and functional misalignments of the foot, such as flat foot, may cause mechanical deviations of the lower limb during walking. The aim of this study was to investigate the effect of foot orthoses on lower extremity joint moment asymmetry during the stance phase of walking in children with asymptomatic flexible flat feet.

METHODS

Fourteen volunteer male children, clinically diagnosed with flexible flat feet, participated in this study. Subjects completed 12 walking trials at a self-selected walking speed while 3-dimensional kinematic and kinetic data were collected for two conditions: shod with no orthoses, and shod with orthoses. The gait asymmetry index for each variable for each subject was defined as: (1-(lesser moment/greater moment)) × 100.

RESULTS

Results reveal no significant differences in ankle or knee joint moment asymmetry. However, the use of foot orthoses decreased asymmetry for the hip abduction moment (P = 0.04) compared to walking without orthoses and also resulted in subtle, non-significant increases in frontal plane subtalar and sagittal plane knee and hip joints moment asymmetry.

CONCLUSION

We conclude that foot orthoses decrease frontal plane hip joint moment asymmetry, but have little effect on ankle and knee joint asymmetry.

Metatarsal Shape and Foot Type: A Geometric Morphometric Analysis

Planus and cavus foot types have been associated with an increased risk of pain and disability. Improving our understanding of the geometric differences between bones in different foot types may provide insights into injury risk profiles and have implications for the design of musculoskeletal and finite-element models. In this study, we performed a geometric morphometric analysis on the geometry of metatarsal bones from 65 feet, segmented from computed tomography (CT) scans. These were categorized into four foot types: pes cavus, neutrally aligned, asymptomatic pes planus, and symptomatic pes planus. Generalized procrustes analysis (GPA) followed by permutation tests was used to determine significant shape differences associated with foot type and sex, and principal component analysis was used to find the modes of variation for each metatarsal. Significant shape differences were found between foot types for all the metatarsals (p < 0.01), most notably in the case of the second metatarsal which showed significant pairwise differences across all the foot types. Analysis of the principal components of variation showed pes cavus bones to have reduced cross-sectional areas in the sagittal and frontal planes. The first (p = 0.02) and fourth metatarsals (p = 0.003) were found to have significant sex-based differences, with first metatarsals from females shown to have reduced width, and fourth metatarsals from females shown to have reduced frontal and sagittal plane cross-sectional areas. Overall, these findings suggest that metatarsal bones have distinct morphological characteristics that are associated with foot type and sex, with implications for our understanding of anatomy and numerical modeling of the foot.

Obesity, foot pain and foot disorders in older men and women

OBJECTIVE

We investigated obesity, foot pain and selected foot disorders, and determined if associations differed by foot posture or dynamic foot function.

METHODS

We included 2445 men and women (4888 feet) from the Framingham Foot Study (2002-2008). A foot examination assessed presence of disorders and pain on each foot. Body mass index (BMI, kg/m²) was categorized as normal (<25), overweight (25-29.99), moderate-obesity (30-34.99) severe-obesity (35+). Foot posture (normal, cavus, planus) and dynamic foot function (normal, supinated, pronated) were defined using plantar pressure measurement system. We used sex-specific logistic regression with generalized estimating equations to account for correlation between two feet of the same person, adjusted for age and stratified by foot posture and dynamic foot function.

RESULTS

Average age was 68±11 years, 56% female, average BMI 28±5kg/m². 18% of feet had pain, 25% hallux valgus, 2% claw toes, 18% hammer toes, 7% overlapping toes. In men, severe-obesity was associated with foot pain (OR=2.4, p=0.002) and claw toes (OR=3.4, p=0.04). In women, overweight, moderate-obesity and severe-obesity were associated with foot pain. Women with severe-obesity were less likely to have hallux valgus. Similar patterns were evident after stratification by foot posture and dynamic foot function.

CONCLUSION

Both men and women were at increased odds of foot pain as BMI increased. Data suggested foot posture and dynamic foot function had no effect, thus are unlikely mechanisms.

The use of a static measure to predict foot posture at midstance during walking

Previous studies have successfully used the longitudinal arch angle (LAA) to assess foot posture, but the measurement consistency and ability of the LAA to predict dynamic foot posture during activity in a variety of foot types have not been evaluated. The purpose of this study was to determine the reliability of the LAA as well as if the clinical method of assessing the LAA could be used to predict the LAA at midstance during walking for supinated, normal, and pronated foot types. The Arch Height Ratio was used to select 35 participants with 12 supinated, 46 normal, and 12 pronated feet. A standard goniometer was used to measure the LAA (CLINIC_LAA) on both feet while standing. Both feet were then filmed using a high speed camera while walking on a treadmill. The LAA was determined by the angle formed by two lines drawn between the markers placed on the first metatatarsal and medial malleolus with the apex the navicular tuberosity. The LAA in midstance (WALK_LAA) was determined using the mean of five walking trials. The reliability of the CLINIC_LAA assessed on both feet by two raters over two days were excellent. There was no difference between the left and right foot for the CLINIC_LAA. The Pearson correlation between CLINIC_LAA and WALK_LAA for all 70 feet was r=0.96 (r²=0.92). The results indicate the LAA is highly predictive of foot posture at midstance in walking explaining over 90% of the variance for a wide range of foot types.

Are flexible flat feet associated with proximal joint problems in children?

The role of flexible flat feet (FF) in the development of musculoskeletal symptoms at joints proximal to the ankle is unclear. We undertook an observational study to investigate the relationship between foot posture and the proximal joints in children. It was hypothesised that reduced arch height would be associated with proximal joint symptoms and altered gait kinematics and kinetics particularly in the transverse plane at the hip and knee. Ninety-five children between the ages of 8-15 were recruited into this ethically approved study. Foot posture was classified using the arch height index (AHI). The frequency of knee and hip/back pain was documented, and each child underwent three dimensional gait analysis. Reduced arch height was associated with increased odds of knee symptoms (p<0.01) and hip/back symptoms (p=0.01). A flat foot posture was also significantly associated with a reduction in the second peak of the vertical ground reaction force (p=0.03), which concomitantly affected late stance hip and knee moments. A reduced AHI was also associated with increased pelvic retraction and increased knee valgus in midstance. No kinematic and kinetic parameter associated with a flat foot posture related to increased proximal joint symptoms in the FF group. Children with a flatter foot posture are more likely to have pain or discomfort at the knee, hip and back; however, the mechanisms by which this occurs remain unclear. Treating FF without explicit understanding of how it relates to symptoms is difficult, and further work in this area is required.

Body Posture After Mastectomy: Comparison Between Immediate Breast Reconstruction Versus Mastectomy Alone

BACKGROUND

Immediate breast reconstruction has been increasingly incorporated as part of breast cancer treatment, especially for the psychological benefits. Currently, there are many options for breast reconstruction surgery, but the impact of the different techniques on body posture has not been widely studied. One study demonstrated that immediate breast reconstruction with a Beker-25 prosthesis could help to preserve body posture after mastectomy; however, there is no evidence regarding the effect of surgery on the body posture of women after breast reconstruction when using autologous tissue.

PURPOSE

The purpose of this paper is to compare the body postures of women who underwent immediate breast reconstruction using an abdominal flap with those of women who underwent mastectomy alone.

DESIGN

This is a cross-sectional study.

SUBJECTS

Seventy-six women diagnosed with breast cancer underwent mastectomy, between 1 and 5 years after the diagnosis, are the participants of the study. Two groups were defined: women who underwent mastectomy and immediate breast reconstruction (n = 38) and women who underwent mastectomy alone (n = 38).

PROCEDURE

To assess body posture, specific anatomical points for obtaining photographs were located and marked in anterior, posterior and right-side and left-side views. The photographs were analysed using Postural Analysis Software/Software de Análise Postural (PAS/SAPO).

RESULTS

In the left lateral view, there was a significant difference in the vertical alignment of the trunk (4.2 vs 3.1; p = 0.05). There were no significant differences between the two groups for the variables in the anterior, posterior or right-side views.

CONCLUSION

Women who underwent mastectomy alone, compared with women who underwent immediate breast reconstruction with abdominal flaps, showed differences in the vertical alignment of the trunk, with greater asymmetry between the acromion and greater trochanter, which can mean trunk rotation. No significant differences were found between the two groups in the alignment of the head, shoulders, scapula, or pelvis. Copyright © 2015 John Wiley & Sons, Ltd.

Lower extremity musculoskeletal disorders in nurses: A narrative literature review

AIMS

The aim of the narrative review was to describe and analyze lower extremity musculoskeletal disorders (MSDs) in nurses and to identify factors associated with these disorders. The ultimate goal was to promote lower extremity health in nurses by recognizing factors that could improve their well-being at work.

METHODS

A systematic search on the Medline, CINAHL, and PsychInfo databases was conducted, producing altogether 945 citations, of which 35 were selected for this review. The studies were analyzed by content analysis.

RESULTS

Nurses have different MSDs in their lower extremities, with which the knee, foot, and ankle being most commonly affected. These problems are often correlated, and problems in the ankle can first appear as knee problems.

CONCLUSIONS

Musculoskeletal disorders in lower extremities and their resulting disability are common within the nursing workforce worldwide, representing a major cause of sick leave absence and often leading to long-term absence.

Leg Muscle Mass and Foot Symptoms, Structure, and Function: The Johnston County Osteoarthritis Project

BACKGROUND

Loss of muscle mass occurs with aging and in lower limbs it may be accelerated by foot problems. In this cross-sectional analysis, we evaluated the relationship of leg muscle mass to foot symptoms (presence or absence of pain, aching, or stiffness), structure while standing (high arch or low arch), and function while walking (pronated or supinated) in a community-based study of Caucasian and African American men and women who were 50-95 years old.

METHODS

In the Johnston County Osteoarthritis Project, leg muscle mass was measured with whole body dual-energy x-ray absorptiometry, and plantar foot pressure data, using predetermined values, were used to classify foot structure and function. Sex-specific crude and adjusted (age, body mass index, and race) linear regression models examined associations of leg muscle mass index (Leg muscle mass [kg]/Height [m](2)) with foot symptoms, structure, and function.

RESULTS

Complete data were available for 1,037 participants (mean age 68 years, mean body mass index 31 kg/m(2), 68% women, 29% African American). In women, pronated foot function was associated with lower leg muscle mass in crude (p = .02), but not adjusted (p = .22), models. A low arch was associated with a higher leg muscle mass in adjusted models for both men and women (p < .01).

CONCLUSIONS

Leg muscle mass was associated with foot structure in our biracial sample, whereas relations between leg muscle mass and foot function were attenuated by age, body mass index, and race. Future longitudinal analyses are needed to explain the temporal relationship between these conditions and how they relate to other aspects of impairment and physical function.

Associations of Region-Specific Foot Pain and Foot Biomechanics: The Framingham Foot Study

BACKGROUND

Specific regions of the foot are responsible for the gait tasks of weight acceptance, single-limb support, and forward propulsion. With region foot pain, gait abnormalities may arise and affect the plantar pressure and force pattern utilized. Therefore, this study's purpose was to evaluate plantar pressure and force pattern differences between adults with and without region-specific foot pain.

METHODS

Plantar pressure and force data were collected on Framingham Foot Study members while walking barefoot at a self-selected pace. Foot pain was evaluated by self-report and grouped by foot region (toe, forefoot, midfoot, or rearfoot) or regions (two or three or more regions) of pain. Unadjusted and adjusted linear regression with generalized estimating equations was used to determine associations between feet with and without foot pain.

RESULTS

Individuals with distal foot (forefoot or toes) pain had similar maximum vertical forces under the pain region, while those with proximal foot (rearfoot or midfoot) pain had different maximum vertical forces compared to those without regional foot pain (referent). During walking, there were significant differences in plantar loading and propulsion ranging from 2% to 4% between those with and without regional foot pain. Significant differences in normalized maximum vertical force and plantar pressure ranged from 5.3% to 12.4% and 3.4% to 24.1%, respectively, between those with and without regional foot pain.

CONCLUSIONS

Associations of regional foot pain with plantar pressure and force were different by regions of pain. Region-specific foot pain was not uniformly associated with an increase or decrease in loading and pressure patterns regions of pain.

Characteristics associated with hallux valgus in a population-based foot study of older adults

OBJECTIVE

Hallux valgus (HV) is common in older adults, but limited studies of risk factors have reported conflicting results. This cross-sectional analysis examined the association of HV with foot pain and other characteristics in older adults.

METHODS

The population-based Framingham Foot Study assessed HV, foot pain, foot structure (planus, rectus, and cavus), current and past high-heeled shoe use, age, and body mass index (BMI). Sex-specific logistic and multinomial logistic regression examined the association of HV and HV with pain with study variables.

RESULTS

Of 1,352 men and 1,725 women (mean ± SD age 66 ± 10.5 years), 22% of men and 44% of women had HV, and 3% of men and 11% of women had HV with pain. Foot pain increased the odds of HV in both sexes (P < 0.05). In women, older age and past high-heeled shoe use increased the odds of HV by 27% and 47%, respectively (P < 0.01), and cavus foot structure decreased the odds of HV by 26% (P = 0.02). BMI >30 kg/m(2) decreased the odds of HV by 33% in men and 45% in women (P < 0.05). In women only, odds of pain and HV versus no pain and no HV were greater with older age and planus foot structure.

CONCLUSION

Our work showed different associations in participants who had HV with pain compared to those without foot pain. In both men and women, strong associations were observed between HV and foot pain and inversely with BMI. Older age was associated with HV in women only, as were protective associations with cavus foot structure.

The associations of leg lean mass with foot pain, posture and function in the Framingham foot study

Background

Foot disorders are common in older adults and associated with impaired lower extremity function. Reduced muscle mass may play a role in the etiology of foot disorders and consequent poor function.

Methods

We examined the association of leg lean mass with foot pain, posture and function among 1,795 individuals (mean age 67 years) from the population-based Framingham Foot Study (2002–2008). Pain was assessed via questionnaire, and a pressure mat classified foot posture (arch: high, low, referent) during standing and function (pronation, supination, referent) during gait. Leg lean mass was measured by whole body dual energy x-ray absorptiometry.

Results

In age- and body mass index-adjusted logistic (pain) and multinomial logistic (posture, function) regression models, a 1-standard deviation increase in leg lean mass was associated with lower odds of foot pain (OR = 0.76, 95% CI: 0.68, 0.86) and pronation (OR = 0.76, 95% CI: 0.67, 0.85), and higher odds of supination (OR = 1.17, 95% CI: 1.04, 1.31). Adjustment for sex attenuated these associations. Higher leg lean mass was associated with lower odds of high arch, even after adjustment for sex (OR = 0.73, 95% CI: 0.60, 0.89).

Conclusions

Though not related to foot pain or function, reduced leg lean mass was associated with extreme foot posture in older adults. Loss of muscle mass with aging may thus play a role in the etiology of functional impairment due to foot disorders.