External feedback during walking improves measures of plantar pressure in individuals with chronic ankle instability

BackgroundIndividuals with chronic ankle instability (CAI) commonly present with an altered walking gait which favors the lateral aspect of their foot. Current rehabilitative protocols are unable to address these gait modifications which are potentially hindering improvements in patient-reported outcomes. Protocols for gait retraining are scarce, thus there is a need to develop intervention strategies and instruments to specifically target foot motion to address gait deficits in individuals with CAI.Research QuestionTo determine the ability of a novel laser device providing external visual feedback (ExFB) during real-time to cause alterations in plantar pressure measures in individuals with CAI.MethodsTwenty-six participants with CAI walked on a treadmill while real-time plantar pressure measures were being recorded during a baseline and feedback condition. Baseline trials were compared with ExFB trials within each subject.ResultsThe ExFB condition was able to significantly reduce plantar pressures on the lateral midfoot and forefoot compared to baseline. A statistically significant medial shift in center of pressure trajectory was also observed in the ExFB condition compared to baseline.SignificanceReal-time external feedback provided by a novel laser device has the ability to reduce lateral column plantar pressures during walking in individuals with CAI.     

Effects of ankle destabilization devices and rehabilitation on gait biomechanics in chronic ankle instability patients: A randomized controlled trial

Patients with chronic ankle instability (CAI) have altered gait patterns, which are characterized by increased inversion positioning during gait. Ankle destabilization devices increase peroneus longus muscle activation during gait, which may increase eversion.ObjectiveTo determine whether incorporating destabilization devices into a 4-week impairment-based rehabilitation program has beneficial effects on gait biomechanics and surface electromyography (sEMG) compared to impairment-based rehabilitation without destabilization devices in CAI patients.DesignRandomized controlled trial.SettingLaboratory.ParticipantsTwenty-six CAI patients.Outcome measuresPatients completed baseline gait trials and were randomized into no device or device groups. Groups completed 4-weeks of rehabilitation with or without devices, and then completed post-intervention gait trials. Lower extremity sagittal and frontal plane kinematics and kinetics and sEMG activity were measured.ResultsThe device group increased dorsiflexion during mid-late stance and had lower normalized sEMG amplitude for the peroneus longus during early stance and mid-swing after rehabilitation. The no device group had less peroneus brevis sEMG activity during early stance after rehabilitation.ConclusionIncorporating destabilization devices in a 4-week rehabilitation program was an effective method of improving dorsiflexion during the stance phase of gait. However, impairment-based rehabilitation, regardless of instability tool, was not effective at improving frontal plane motion.     

Surface electromyography and plantar pressure during walking in young adults with chronic ankle instability

Purpose

Lateral ankle sprains are common and can manifest into chronic ankle instability (CAI) resulting in altered gait mechanics that may lead to subsequent ankle sprains. Our purpose was to simultaneously analyse muscle activation patterns and plantar pressure distribution during walking in young adults with and without CAI.

Methods

Seventeen CAI and 17 healthy subjects walked on a treadmill at 4.8 km/h. Plantar pressure measures (pressure–time integral, peak pressure, time to peak pressure, contact area, contact time) of the entire foot and nine specific foot regions and medial–lateral location of centre of pressure (COP) were measured. Surface electromyography (EMG) root mean square (RMS) amplitudes throughout the entire stride cycle and area under RMS curve for 100 ms pre-initial contact (IC) and 200 ms post-IC for anterior tibialis, peroneus longus, medial gastrocnemius, and gluteus medius were collected.

Results

The CAI group demonstrated a more lateral COP throughout the stance phase (P < 0.001 and Cohen’s d > 0.9 for all 10 comparisons) and significantly increased peak pressure (P = 0.025) and pressure–time integral (P = 0.049) under the lateral forefoot. The CAI group had lower anterior tibialis RMS areas (P < 0.001) and significantly higher peroneus longus, medial gastrocnemius, and gluteus medius RMS areas during 100 ms pre-IC (P < 0.003). The CAI group had higher gluteus medius sEMG amplitudes during the final 50 % of stance and first 25 % of swing (P < 0.05).

Conclusions

The CAI group had large lateral deviations of their COP location throughout the entire stance phase and increased gluteus medius muscle activation amplitude during late stance through early swing phase.

Level of evidence

III.

     

Effects of gait training with auditory biofeedback on biomechanics and talar cartilage characteristics in individuals with chronic ankle instability: A randomized controlled trial

BackgroundAltered walking gait is a typical impairment following ankle sprains which may increase susceptibility to recurring injuries and development of posttraumatic osteoarthritis at the ankle. There is a lack of targeted gait training interventions focusing on specific modifications in individuals with chronic ankle instability (CAI). Additionally, there is a need to focus on cartilage health changes following gait training to mitigate osteoarthritis progression.Research questionTo determine the immediate and retention effects of gait training using auditory biofeedback (AudFB) in patients with chronic ankle instability (CAI) on biomechanics and talar cartilage characteristics.MethodsEighteen participants with CAI were randomly assigned into Control (n = 7) or AudFB (n = 11) groups. Each group completed 8-sessions of 30-minute treadmill walking. The AudFB group received biofeedback through a pressure sensor fashioned to the lateral foot and instructions to walk while avoiding noise from the sensor. The Control group did not receive instructions during sessions. An in-shoe insole system measured peak pressure, maximum force, and center of the pressure gait line (COP) during walking. Ultrasonography captured talar cartilage thickness and echo intensity before and after walking. Biomechanics and ultrasound were measured at baseline, immediately, and 1-week after the intervention. Repeated measures mixed-methods analysis of variance assessed changes within groups across time.ResultsThe AudFB group significantly reduced pressure and force in the lateral foot and medially shifted their COP at Immediate and 1-week Post. There were no observed changes in the Control group. In addition, neither group demonstrated changes in ultrasound measures at follow-up.SignificanceImplementation of auditory biofeedback during gait training can be a valuable tool for clinicians treating patients with CAI.     

The effects of metronome frequency differentially affects gait on a treadmill and overground in people with Parkinson disease

BackgroundTreadmills and rhythmic auditory cueing can influence stepping rhythm for individuals with Parkinson disease (PD). Of concern, however, is that auditory cueing directly addresses the temporal features of gait, whereas adjusting step length may be more important for people with PD. Stepping to a faster cadence when walking overground may increase gait speed, but without requiring an increased step length. Furthermore, given the potentially valuable role of walking on a treadmill for individuals with PD, we are concerned that increasing cadence with rhythmic auditory cueing while walking at a constant treadmill speed will induce even shorter steps.Research questionWhat is the effect of different metronome cue frequencies on spatiotemporal gait parameters when walking overground compared to walking on a treadmill in people with PD?MethodsUsing a repeated-measures design, 21 people with PD (stage 1–3) walked overground and on a treadmill with and without metronome cues of 85 %, 100 %, and 115 % of their baseline cadence frequency for one minute each. We assessed step length, and cadence during all conditions. Gait speed was assessed during overground gait.ResultsAn interaction effect between cue frequency and walking environment revealed that participants took longer steps during the 85 % condition on the treadmill only. When walking overground, metronome cues of 85 % and 115 % of baseline cadence yielded decreases and increases, respectively, in both cadence and gait speed with no associated change in step length.SignificanceThese data suggest that people with PD are able to alter spatiotemporal gait parameters immediately when provided the appropriate metronome cue and walking environment. We propose to target shortened step lengths by stepping to the beat of slow frequency auditory cues while walking on a treadmill, whereas the use of fast frequency cues during overground walking can facilitate faster walking speeds.     

Effects of two types of foot orthoses on lower limb muscle activity before and after a one-month period of wear

The purpose of this study was to quantify the effects of two types of foot orthoses (FOs) on muscle activity during walking. Twenty-one healthy participants were recruited to walk on a five-meter walkway with a control condition (no FOs) and two experimental conditions (FOs and FOs with lateral bar). The experimental protocol was performed before and after a one-month period of wear for each experimental condition. Electromyographic signals were recorded for six muscles (gluteus medius, vastus lateralis, medial gastrocnemius, lateral gastrocnemius, peroneus longus and tibialis anterior). Mean muscle activity was analyzed during the contact, the combined midstance/terminal stance and the pre-swing phases of gait. Peak amplitude and time to peak amplitude were quantified during the stance phase. Unacceptable level of variability was observed between the testing sessions. Therefore, no comparisons were performed to compare the effects of the experimental conditions between testing sessions. After a one-month period of wear, FOs with lateral bar decreased peak amplitude and mean activity of the peroneus longus muscle during the combined midstance/terminal stance phase and FOs decreased peak amplitude and mean activity of the tibialis anterior muscle during the contact phase compared to a control condition. In conclusion, repeated-test design should be used with caution when assessing the muscular adaptation to the wear of FOs for a certain period of time. More studies are needed to determine if the decreased activity of the peroneus longus muscle could be of benefit to treat pathologies such as peroneal tendinopathy or lateral ankle instability.     

Temporal patterns of plantar pressures and lower-leg muscle activity during walking: effect of speed

Plantar pressure assessment is a tool useful for study of the gait cycle. In this study, we present a means of assessing the gait cycle using a temporal analysis of plantar pressures and lower-leg muscle activities. Plantar pressures and surface electromyography (EMG) of the tibialis anterior (TA) and medial gastrocnemius (MG) muscles were recorded as 19 men walked on a treadmill at seven speeds between 0.45 and 1.79 m/s. A typical 'heel strike to toe off' gait pattern was observed. Speed had minimal effects on the shapes of the muscle EMG root-mean-square-and plantar pressure-time curves except for the pressure-time curves in the heel and midfoot. A linear relationship was found between speed and peak pressures in the heel, medial forefoot, and toes; pressures in these regions increased by 91-289% going from 0.45 to 1.79 m/s. The temporal pressure changes in the forefoot and toes were paralleled by changes in MG muscle activity (i.e., cross-correlations of > or =0.90); TA muscle activity was not cross-correlated with the temporal pressure patterns in any region. However, the peak values of TA muscle activity were found to be highly correlated across speeds with peak pressures in the heel and toes (i.e., r > or =0.98); similar high correlations were found between peak values of MG muscle activity and heel pressure. In summary, these data collected on able-bodied persons during motorized treadmill walking can be useful for comparison to those of patients undergoing treadmill evaluations for atypical gait cycle patterns and for tracking the progress of patients during gait rehabilitation.     

Muscle activations during functional tasks in individuals with chronic ankle instability: a systematic review of electromyographical studies

BackgroundIt has been reported that individuals with chronic ankle instability (CAI) show motor control abnormalities. The study of muscle activations by means of surface electromyography (sEMG) plays a key role in understanding some of the features of movement abnormalities.Research questionDo common sEMG activation abnormalities and strategies exists across different functional movements?MethodsLiterature review was conducted on PubMed, Web-of-Science and Cochrane databases. Studies published between 2000 and 2020 that assessed muscle activations by means of sEMG during any type of functional task in individuals with CAI, and used healthy individuals as controls, were included. Methodological quality was assessed using the modified Downs&Black checklist. Since the methodologies of different studies were heterogeneous, no meta-analysis was conducted.ResultsA total of 63 articles investigating muscle activations during gait, running, responses to perturbations, landing and hopping, cutting and turning; single-limb stance, star excursion balance task, forward lunges, ball-kicking, y-balance test and single-limb squatting were considered. Individuals with CAI showed a delayed activation of the peroneus longus in response to sudden inversion perturbations, in transitions between double- and single-limb stance, and in landing on unstable surfaces. Apparently, while walking on ground there are no differences between CAI and controls, walking on a treadmill increases the variability of muscles activations, probably as a “safety strategy” to avoid ankle inversion. An abnormal activation of the tibialis anterior was observed during a number of tasks. Finally, hip/spine muscles were activated before ankle muscles in CAI compared to controls.ConclusionThough the methodology of the studies herein considered is heterogeneous, this review shows that the peroneal and tibialis anterior muscles have an abnormal activation in CAI individuals. These individuals also show a proximal muscle activation strategy during the performance of balance challenging tasks. Future studies should investigate whole-body muscle activation abnormalities in CAI individuals.     

The impact of attentional, auditory, and combined cues on walking during single and cognitive dual tasks in Parkinson disease

Auditory and attentional cues improve gait in Parkinson disease (PD), but it is unclear if combining the two cueing strategies offers additional benefit. Further, the effect of a secondary cognitive task on cue efficacy is unknown. Therefore, this study aimed to assess the effects of cue type and task complexity on gait in PD. 11 participants with PD, 11 age-matched controls, and 11 young controls performed 3 walking trials on a GAITRite walkway under the following cueing conditions: no cue (baseline), rhythmic auditory cue at 10% below (AUD-10) and 10% above (AUD+10) self selected cadence, attentional cue (ATT; "take long strides"), and a combination of AUD and ATT (COM-10, COM+10). Each condition was also performed concurrently with a secondary word generation task (dual task, DT). Baseline gait velocity and stride length were less for those with PD and age-matched controls compared to young controls, and the ability of those with PD to use cues differed from the other groups. Gait velocity and stride length increased in PD with ATT, but not with auditory cues. Similar increases in gait velocity and stride length were observed with the combined cues, but additional benefit beyond ATT alone was not observed. Cues did not improve gait velocity during dual task walking, although stride length did increase with COMB+10. It appears persons with PD are able to benefit from attentional cueing and can combine attentional and auditory cues, but do not gain additional benefit from such a combination. During walking while performing a secondary cognitive task, attentional cues may help to facilitate a longer stride length.     

Comparison of muscle activity during walking in subjects with and without diabetic neuropathy

The purpose of this study was to compare muscle activity and joint moments in the lower extremities during walking between subjects with diabetic neuropathy (DN) and control subjects. Tests were performed on nine subjects with DN, and nine age, gender, and weight-matched controls. Onset and cessation times of lower extremity electromyographic (EMG) activity and joint moments were determined. Results demonstrated that subjects with DN had less ankle mobility, slower walking speeds, longer stance phases, and lower peak ankle dorsiflexion, ankle plantar flexion, and knee extension moments than control subjects. Onset times with respect to heel-strike (HS) for the soleus, medial gastrocnemius, and medial hamstring muscles were significantly earlier during the gait cycle (GC) in subjects with DN than in control subjects. The cessation times of soleus, tibialis anterior, vastus medialis, and medial hamstring muscles were significantly prolonged in subjects with DN. Subjects with DN showed more co-contractions of agonist and antagonist muscles at the ankle and knee joints during stance phase compared with control subjects. These gait changes and co-contractions may allow subjects with DN to adopt a safer, more stable gait pattern to compensate for diminished sensory information from the ankle and the foot. The premature activation of soleus and medial gastrocnemius muscles in subjects with DN could be contributing to abnormal forefoot plantar pressure distribution. Additional research is needed to clarify the relationship between the premature activation of triceps surae muscles and the forefoot plantar pressure parameters in subjects with DN.     

Effects of rocker radii with two longitudinal bending stiffnesses on plantar pressure distribution in the forefoot

IntroductionOutsole parameters of the shoe can be adapted to offload regions of pain or region of high pressures. Previous studies already showed reduced plantar pressures in the forefoot due to a proximally placed apex position and higher longitudinal bending stiffness (LBS). The aim of this study was to determine the effect of changes in rocker radii and high LBS on the plantar pressure profile during gait.Method10 participants walked in seven shoe conditions of which one control shoe and six rocker shoes with small, medium and large rocker radii and low and high longitudinal bending stiffness. Pedar in-shoe plantar pressure measuring system was used to quantify plantar pressures while walking on a treadmill at self-selected walking speed. Peak plantar pressure, maximum mean pressure and force-time integral were analyzed with Generalized Estimated Equation (GEE) and Tukey post hoc correction (α = .05).ResultsSignificantly lower plantar pressures were found in the first toe, toes 2–5, distal and proximal forefoot in all rocker shoe conditions as compared to the control shoe. Plantar pressures in the first toe and toes 2–5 were significantly lower in the small radius compared to medium and large radii. For the distal forefoot both small and medium radii significantly reduced plantar pressure compared to large radii. Low LBS reduced plantar pressure at the first toe significantly compared to high LBS independent of the rocker radius. Plantar pressures in the distal forefoot and toes 2–5 were lower in high LBS compared to low LBS.ConclusionManipulation of the rocker radius and LBS can effectively reduce peak plantar pressures in the forefoot region during gait. In line with previous studies, we showed that depending on the exact target location for offloading, different combinations of rocker radius and LBS need to be adopted to maximize treatment effects.     

Unilateral non-electric assistive walking device helps neurological and orthopedic patients to improve gait patterns

BackgroundPathological gait patterns are common in neurological and orthopedic patients. These put them at risk of falling and restrict their autonomy and social participation. Novel assistive walking devices are designed to actively support physiological gait patterns by means of motor guidance and mechanical support of the lower limbs.Research questionDoes a non-electric assistive walking device powered by a cam-spring mechanism (aLQ, Imasen) improve or otherwise affect pathological gait patterns in neurological and orthopedic patients?MethodsA three-dimensional instrumented gait analysis was conducted on a treadmill (quasar, hp cosmos) using spatiotemporal, kinetic, and kinematic data obtained from synchronized motion capturing (Miqus M3, Qualisys), surface EMG (sEMG; Ultium, Noraxon), and pressure distribution measurements (FMD-T, Zebris). Participants with impaired walking were tested in a randomized repeated measures design (assisted/unassisted; at preferred/fast speed) and analyzed with regard to their medical condition (orthopedic or neurological group, n = 20 each).ResultsIn both groups, participants showed a significant increase of step length and decrease of cadence during assisted walking compared to baseline. Immediate kinematic effects included enhanced sagittal hip flexion but reduced extension. On the contrary, knee joint angles and muscle activity of M. gastrocnemius and M. rectus femoris seemed to be unaffected by the aLQ device.SignificanceParticipants appear to benefit from the assistive walking device regarding gait and movement patterns, which suggests that the tested device may help to improve patients’ functional health status and quality of life. Activities of daily living (ADLs) that involve extensive hip flexion like stairs or curb climbing are promising applications. We propose the implementation of an invertible cam-spring that provides an additional resistance training option.     

The effects of an ankle destabilization device on muscular activity while walking

Chronic Ankle Instability sprain causes are unclear and many factors or mechanisms may contribute to recurrence of this injury. The aim of the study was to investigate how an ankle destabilization device affects the EMG patterns of the ankle muscles during ankle stabilization against inversion. The left foot was equipped with a mechanical device mounted under the heel of the shoe. This mechanical device induces subtalar joint destabilization necessitating the control of ankle muscles. Surface electrodes were placed over the tibialis anterior, the peroneus longus, the peroneus brevis, the gastrocnemius lateral, and the gastrocnemius medial. Nine healthy subjects (mean age 37+/-12 yr; mean mass 68+/-17 kg; mean height 1.73+/-0.7 m) were instructed to walk normally along a tape fixed on the floor. The ankle destabilization device altered the walking pattern of all subjects. More specifically, the walking pattern is disturbed resulting in higher amplitude of the EMG activity of the peroneal muscles and the Tibialis Anterior and anticipatory reactions in the peroneal muscles. The results suggest that the ankle destabilization device could be beneficial for rehabilitation programs especially during the training of walking. Using this material may help to a specific reinforcement of muscles involved in anti-inversion ankle movement.     

The effect of partial weight bearing in a walking boot on plantar pressure distribution and center of pressure

Physicians routinely prescribe partial weight bearing in a walking boot following fractures of the lower limbs in order to produce the needed mechanical environment to facilitate healing. Plantar pressure measurements can provide key information regarding the mechanical environment experienced by lower limb bones. The effect of walking boots on plantar pressure distribution has been well reported, however, the combined effects of partial weight bearing and walking boots on plantar pressure distribution and center of pressure is unknown. Thirteen healthy volunteers with no known gait pathologies were fitted with a multi-pressure sensor insole that recorded their plantar pressure distribution during four walking trials: (i) normal walking, (ii) full weight bearing in a walking boot, (iii) 27 kg partial weight bearing in a walking boot and (iv) 9 kg partial weight bearing in a walking boot. Results demonstrated that changing from trial (i) to (iv) resulted in a posterior shift in weight distribution; the percentage of total weight experienced at the heel increased while the percentage of total weight experienced at the forefoot (both medial and lateral) and the hallux decreased. Center of pressure trajectories also shifted more posteriorly. Additionally, while in a walking boot the gait during full and partial weight bearing resulted in more even foot loading.     

Effect of customised preformed foot orthoses on gait parameters in children with juvenile idiopathic arthritis: A multicentre randomised clinical trial

BackgroundChildren with juvenile idiopathic arthritis (JIA) can experience significant physical impairment of the lower extremity. Prolonged joint disease and symptoms may cause gait alterations such as reduced walking speed and increased plantar pressures in diseased areas of their feet. There is limited robust clinical trials investigating the effect of non-invasive mechanical therapies such as foot orthoses (FOs) on improving gait parameters in children with JIA.Research questionAre customised preformed FOs effective in improving gait parameters in children with JIA?MethodsA multicentre, parallel design, single-blinded randomised clinical trial was used to assess the gait impacts of customised preformed FOs on children with JIA. Children with a diagnosis of JIA, exhibiting lower limb symptoms and aged 5–18 were eligible. The trial group received a low-density full length, Slimflex Simple device which was customised chair side and the control group received a sham device. Peak pressure and pressure time integrals were used as the main gait outcomes and were measured using portable Tekscan gait analysis technology at baseline, 3 and 6 months. Differences at each follow-up were assessed using the Wilcoxon rank sum test.Results66 participants were recruited. Customised preformed FOs were effective in altering plantar pressures in children with JIA versus a control device. Reductions of peak pressures and pressure time integrals in the heel, forefoot and 5th metatarsophalangeal joint were statistically significant in favour of the trial group. This was associated with statistically significant increased midfoot contact with the trial device at baseline, 3 and 6-month data collections. The trial intervention was safe and well accepted by participants, which is reflected in the high retention rate (92%).SignificanceClinicians may prescribe customised preformed FOs in children with JIA to deflect pressure from painful joints and redistribute from high pressure areas such as the rearfoot and forefoot.     

Effect of gait speed changes on foot loading characteristics in children

Gait speed has been shown to influence foot loading patterns in adults but the mechanism has not been investigated in children. The present study investigated the effects of changes in gait speed on foot loading characteristics in 20 typically developing children who participated in plantar pressure measurements at normal, slow and fast walking speeds. In spite of shorter contact times in the fast walking speed condition, significantly increased foot loading was seen in the hindfoot, medial and central forefoot and toes while it slightly decreased in the lateral midfoot and forefoot. The results generally confirm the findings in adults that gait speed does not uniformly affect foot loading characteristics and that these effects should be kept in mind when comparing different subject groups or children at repeated measurement occasions.     

Comparison of foot muscle morphology and foot kinematics between recreational runners with normal feet and with asymptomatic over-pronated feet

Over-pronated feet are common in adults and are associated with lower limb injuries. Studying the foot muscle morphology and foot kinematic patterns is important for understanding the mechanism of over-pronation related injuries. The aim of this study is to compare the foot muscle morphology and foot inter-segmental kinematics between recreational runners with normal feet and those with asymptomatic over-pronated feet. A total of 26 recreational runners (17 had normal feet and 9 had over-pronated feet) participated in this study and their foot type was assessed using the 6-item Foot Posture Index. Selected foot muscles were scanned using an ultrasound device and the scanned images were processed to measure the thickness and cross-sectional area of the muscles. Muscles of interest include abductor hallucis, abductor digiti minimi, flexor digitorum brevis and longus, tibialis anterior and peroneus muscles. Foot kinematic data during walking was collected using a 3D motion capture system incorporating the Oxford Foot Model. The results show that individuals with over-pronated feet have larger size of abductor hallucis, flexor digitorum brevis and longus and smaller abductor digiti minimi than controls. Higher rearfoot peak eversion and forefoot peak supination during walking were observed in individuals with over-pronated feet. However, during gait the forefoot peak abduction was comparable. These findings indicate that in active asymptomatic individuals with over-pronated feet, the foot muscle morphology is adapted to increase control of the foot motion. The morphological characteristics of the foot muscles in asymptomatic individuals with over-pronated feet may affect their foot kinematics and benefit prevention from injuries.     

Foot loading patterns can be changed by deliberately walking with in-toeing or out-toeing gait modifications

The present study shows how foot loading patterns may be deliberately altered by either in-toeing or out-toeing gait during barefoot walking. The results indicate that in-toeing increasingly loads the lateral aspects of the midfoot and forefoot by as much as 61% and 49%, respectively, whereas out-toeing intensifies the load on the medial aspect, i.e. predominantly the medial midfoot and medial forefoot by as much as 72% and 52%. These findings are being discussed with respect to the potential benefits of consciously altering the gait pattern in order to off-load certain plantar regions.     

Understanding the role of foot biomechanics on regional foot orthosis deformation in flatfoot individuals during walking

BackgroundFoot orthoses (FOs) are one of the most common interventions to restore normal foot mechanics in flatfoot individuals. New technologies have made it possible to deliver customized FOs with complex designs for potentially better functionalities. However, translating the individuals’ biomechanical needs into the design of customized FOs is not yet fully understood.Research questionOur objective was to identify whether the deformation of customized FOs is related to foot kinematics and plantar pressure during walking.MethodsThe kinematics of multi-segment foot and FOs contour were recorded together with plantar pressure in 17 flatfoot individuals while walking with customized FOs. The deformation of FOs surface was predicted from its contour kinematics using an artificial neural network. Plantar pressure map and deformation were divided into five anatomically based regions defined by the corresponding foot segments. Forward stepwise linear mixed models were built for each of the four gait phases to determine the feet-FOs interaction.ResultsIt was observed that some associations existed between foot kinematics and pressure with regional FOs deformation. From heel-strike to foot-flat, longitudinal arch angle was associated with FOs deformation in forefoot. From foot-flat to midstance, rearfoot eversion accounted for variation in the deformation of medial FOs regions, and forefoot abduction for the lateral regions. From midstance to heel-off, rearfoot eversion, longitudinal arch angle, and plantar pressure played significant role in deformation. Finally, from heel-off to toe-off, forefoot adduction affected the deformation of forefoot and midfoot.SignificanceThis study provides guidelines for designing customized FOs. Flatfoot individuals with excessive rearfoot eversion or very flexible medial arches require more support on medial FOs regions, while the ones with excessive forefoot abduction need the support on lateral regions. However, a compromise should be made between the level of support and the level of increase in plantar pressure to avoid stress on foot structures.