Automatic force plate contact detection protocol for computerized gait analysis

BackgroundThe usability and evaluability of a computerized gait analysis requires correct force plate foot contact, with the force measuring plates embedded in the ground, in order to obtain kinetic data.Research questionThis article describes a technical development that facilitates the process flow of computerized gait analysis. Software has been developed that automatically recognizes, counts and documents the correct force plate foot contactsMethodsA software program has been developed. Programming was done in Microsoft® C# using the ViconDatastreemSDK.dotNet® Dynamic Link Library (DLL) developed by Vicon®. The program queries the positions of the foot markers and the electrical signals of the force plates.Results and significanceThe program, which runs parallel to the Vicon® data acquisition software, simultaneously displays the information about the correct force plate foot contacts in a graphical user interface (GUI). After the measurement, an automatically generated protocol of the evaluable walks is available in tabular form     

Mobile inertial sensor based gait analysis: Validity and reliability of spatiotemporal gait characteristics in healthy seniors

Gait analysis is commonly used to identify gait changes and fall risk in clinical populations and seniors. Body-worn inertial sensor based gait analyses provide a feasible alternative to optometric and pressure based measurements of spatiotemporal gait characteristics. We assessed validity and relative and absolute reliability of a body-worn inertial sensor system (RehaGait^®) for measuring spatiotemporal gait characteristics compared to a standard stationary treadmill (Zebris^®). Spatiotemporal gait parameters (walking speed, stride length, cadence and stride time) were collected for 24 healthy seniors (age: 75.3 ± 6.7 years) tested on 2 days (1 week apart) simultaneously using the sensor based system and instrumented treadmill. Each participant completed walking tests (200 strides) at different walking speeds and slopes. The difference between the RehaGait^® system and the treadmill was trivial (Cohen’s d <0.2) except for speed and stride length at slow speed (Cohen’s d, 0.35 and 0.49, respectively). Intraclass correlation coefficients (ICC) were excellent for temporal gait characteristics (cadence and stride time; ICC: 0.99–1.00) and moderate for stride length (ICC: 0.73–0.89). Both devices had excellent day-to-day reliability for all gait parameters (ICC: 0.82–0.99) except for stride length at slow speed (ICC: 0.74). The RehaGait^® is a valid and reliable tool for assessing spatiotemporal gait parameters for treadmill walking at different speeds and slopes.     

The Primary Gait Screen in Parkinson’s disease: Comparison to standardized measures

BackgroundPersons with Parkinson’s disease exhibit gait deficits during comfortable-pace overground walking and data from pressure sensitive mats have been used to quantify gait performance. The Primary Gait Screen is a new assessment which includes gait initiation, overground walking, turning, and gait termination. Although overground assessments are useful, the Primary Gait Screen offers a more complex evaluation than traditional gait assessments.Research questionIs the overground walking portion of the Primary Gait Screen comparable to traditional gait assessments?MethodsPersons with Parkinson’s disease (N = 175; 47 F, 128 M; 67 ± 9 yrs) prospectively completed 4 passes at a self-selected speed and two trials of the Primary Gait Screen on an 8 m long pressure-sensing mat. Spatiotemporal gait variables were computed and a repeated-measures MANOVA with a Bonferroni correction compared the spatiotemporal variables from the Primary Gait Screen to the self-selected trials: gait velocity, cadence, step length, step time, and stride length.ResultsThe analyses failed to detect differences between the Primary Gait Screen and self-selected trials for gait velocity, step length, or stride length (p > .01). Post-hoc tests revealed decreased cadence and increased step time were the only differences between the Primary Gait Screen trials and the self-selected trial (p < .001).SignificanceDifferences seen in cadence and step time during the Primary Gait Screen may be attributed to patients’ strategy, but are likely not clinically meaningful. The Primary Gait Screen appears to be a comparable assessment of overground walking in persons with Parkinson’s disease, and may be a useful and accurate clinical assessment of walking.     

Exploring the feasibility and acceptability of sensor monitoring of gait and falls in the homes of persons with multiple sclerosis

Gait parameters variability and falls are problems for persons with MS and have not been adequately captured in the home. Our goal was to explore the feasibility and acceptability of monitoring of gait and falls in the homes of persons with MS over a period of 30 days. To test the feasibility of measuring gait and falls for 30 days in the home of persons with MS, spatiotemporal gait parameters stride length, stride time, and gait speed were compared. A 3D infrared depth imaging system has been developed to objectively measure gait and falls in the home environment. Participants also completed a 16-foot GaitRite electronic pathway walk to validate spatiotemporal parameters of gait (gait speed (cm/s), stride length (cm), and gait cycle time(s)) during the timed 25 foot walking test (T25FWT). We also documented barriers to feasibility of installing the in-home sensors for these participants. The results of the study suggest that the Kinect sensor may be used as an alternative device to measure gait for persons with MS, depending on the desired accuracy level. Ultimately, using in-home sensors to analyze gait parameters in real time is feasible and could lead to better analysis of gait in persons with MS.     

Concurrent validity and intrasession reliability of the IDEEA accelerometry system for the quantification of spatiotemporal gait parameters

The aim of this pilot study was to evaluate concurrent validity and intrasession reliability of the IDEEA (Minisun, Fresno, CA) accelerometry system (and associated software) with force plate measurements for spatiotemporal gait variables recorded during normal walking. Ten healthy individuals were asked to walk at a self-selected comfortable speed, over five multicomponent force plates embedded into the walkway floor. For each trial, spatiotemporal gait parameters (single support time, cadence, speed, step and stride length) obtained by the force plates were compared to those recorded by IDEEA. Concurrent (criterion-related) validity between the two systems was analysed with intraclass correlation (ICC) (2,1). Intrasession reliability was quantified by using coefficient of variations (CV) and ICC. For the ensemble of the parameters, ICC (2,1) ranged between 0.998 (cadence) and 0.784 (step length right) (p<0.001-0.01). However, speed, step length and stride length were significantly lower for IDEEA (~7%; p<0.001) compared to force plate data. Intrasession reliability of IDEEA was excellent, with CV lower than 5.7 and ICC higher than 0.961. The present accelerometry system demonstrated strong concurrent validity for the assessment of spatiotemporal gait parameters. However, spatial variables (stride and step length) and walking speed were significantly underestimated compared with analyses using force plates.     

Foot kinematics and kinetics during adolescent gait

Gait analysis models typically analyze the ankle joint complex and treat the foot as a rigid segment. Such models are inadequate for clinical decision making for patients with foot impairments. While previous multisegment foot models have been presented, no comprehensive kinematic and kinetic databases for normal gait exist. This study provides normative foot joint angles, moments and powers during adolescent gait. Eighteen subjects were evaluated using 19 retroreflective markers, six cameras, a pressure platform and a force plate. A nine-segment model determined 3D angles, 3D moments, and powers in eight joints or joint complexes. A complete sets of sagittal, coronal and frontal plane results are presented. Results indicate that single link models of the foot significantly overestimate ankle joint powers during gait. Understanding normal joint kinematics and kinetics during gait will provide a baseline for documenting impairments in patients with foot disorders.     

Self-paced treadmills do not allow for valid observation of linear and nonlinear gait variability outcomes in patients with Parkinson’s disease

BackgroundDue to the imposed constant belt speed, motorized treadmills are known to affect linear and nonlinear gait variability outcomes. This is particularly true of patients with Parkinson’s Disease where the treadmill can act as an external pacemaker. Self-paced treadmills update the belt speed in response to the subject's walking speed and might, therefore, be a useful tool for measurement of gait variability in this patient population. This study aimed to compare gait variability during walking at self-paced and constant treadmill speeds with overground walking in individuals with PD and individuals with unimpaired gait.MethodsThirteen patients with Parkinson’s Disease and thirteen healthy controls walked under three conditions: overground, on a treadmill at a constant speed, and using three self-paced treadmill modes. Gait variability was assessed with coefficient of variation (CV), sample entropy (SampEn), and detrended fluctuation analysis (DFA) of stride time and length. Systematic and random error between the conditions was quantified.ResultsFor individuals with PD, error in variability measurement was less during self-paced modes compared with constant treadmill speed for stride time but not for stride length. However, there was substantial error for stride time and length variability for all treadmill conditions. For healthy controls the error in measurement associated with treadmill walking was substantially less.SignificanceThe large systematic and random errors between overground and treadmill walking prohibit meaningful gait variability observations in patients with Parkinson’s Disease using self-paced or constant-speed treadmills.     

Basic gait and symmetry measures for primary school-aged children and young adults whilst walking barefoot and with shoes

This study investigated the basic spatio-temporal gait measures of 898 primary school-aged children (5–13 years) and 82 young adults (18–27 years). Participants completed 6–8 walks at preferred speed along a GAITRite walkway whilst barefoot and whilst wearing athletic shoes or runners. Outcome measures (non-normalized and normalized) were gait speed, cadence, step and stride length, support base, single and double support, stance duration, foot angle and associated symmetry measures. Non-normalized measures of speed, step and stride length, support base and foot angle increased with age whereas cadence reduced. Normalized measures remained unchanged with age in children whereas the young adults (both conditions) exhibited a 2.3% reduction in single support, a 5.1% increase in double support and a 2.6% increase in stance duration (p < 0.0001). For the entire sample, shoes increased walking speed by 8 cm s⁻¹, step length by 5.5 cm, stride length by 11.1 cm and base of support by 0.5 cm. In contrast, foot angle and cadence reduced by 0.1° and 3.9 steps min⁻¹ respectively. Shoes increased both double support (1.6%) and stance time (0.8%), whereas single support reduced by 0.8%. Symmetry remained unaffected by age. On average, measures of step and stride symmetry (combining both conditions) fell around 0.7 cm, whereas measures of symmetry for step and stance time, single and double support fell around 0.6%. Footwear significantly affected gait (p < 0.0001). Gait may not be mature by age 13. Gait is symmetrical in healthy children and young adults but may change with pathology.     

Impact of mediolateral segmentation on a multi-segment foot model

MacWilliams et al. report their progress on a multi-segment foot model, including mediolateral segmentation, from which they calculate kinematics and kinetics [MacWilliams BA, Cowley M, Nicholson DE. Foot kinematics and kinetics during adolescent gait. Gait Posture 2003;17:214–24]. Their methods are generally well described, and in concept, lead us to new insights regarding foot biomechanics during gait, including kinetics of several joints within the foot itself. However, forces and moments (i.e., force systems) between mediolaterally adjacent segments were ignored in their inverse dynamics calculations. We show theoretically that these omitted force systems instead corrupt the calculated proximal force systems. We also show empirically that physiologically reasonable moment-arms (10–20 mm) and omitted forces (one to four bodyweights) could change both the shape and magnitude of the calculated proximal force systems. In this regard, we demonstrate that these kinetic data need to be viewed with caution. Finally, we extend the concept used in our analysis to general biomechanical modeling.     

The influence of stride-length on plantar foot-pressures and joint moments

Purpose

Joint moments have been acknowledged as key factors in understanding gait abnormalities. Gait velocity is further known to affect joint moments and foot pressures. Keeping gait velocity constant is thus a strategy to cancel out the influence of different preferred gait speed between groups. But even if gait velocity is controlled, individuals can choose different stride length–stride frequency combinations to cope with an imposed gait velocity.

Scope

To understand the influence of stride frequency–stride length on joint moments and plantar pressures.

Methods

Twenty healthy young adults had to cross an 8 m walkway with a walking speed of 1.3 m s⁻¹. The wooden walkway was equipped with a force and a pressure platform. While walking speed was kept constant each participant walked with five different imposed stride lengths (SL): preferred (SL0); with a decrease of 10% (SL − 10); with a decrease of 20% (SL − 20); with an increase of 10% (SL + 10) and with an increase of 20% (SF + 20).

Results

Ankle and knee joint moments significantly decreased with a decrease in SL. A significant (p < .05) lower peak pressure was achieved with a decreased SL under the heel, toes and midfoot.

Discussion/conclusion

The results showed that a change in stride lengths alters both, joint moments and foot pressures with clinically interesting indications. Redistribution of joint moments in the elderly for example might rather result from decreased SL than from age.     

Validation of shoe-worn Gait Up Physilog®5 wearable inertial sensors in adolescents

BackgroundGait Up Physilog® wearable inertial sensors are a powerful alternative to traditional laboratory-based gait assessment for children with gait impairment. To build clinician trust in these devices and ultimately facilitate their use outside confined spaces, studies have examined performance of previous versions of Physilog® wearable inertial sensors but predominant focus has been on older adults. Despite their different gait patterns and behavioural/cognitive profiles, there are limited studies in children.Research questionTo determine whether key spatiotemporal gait parameters (stride length, time and velocity) collected by shoe-worn Physilog®5 sensors in a hallway assessment protocol are a valid method of gait assessment in typically developing adolescents aged 12–15 years.MethodsA total 30 typically developing participants (50 % female) median age 13.7 (interquartile range 2.34) were assessed in an exploratory study whilst walking at self-selected speed over the GAITRite® electronic walkway, concurrently wearing Physilog®5 sensors. Concurrent validity was analysed by Lin’s concordance correlation coefficient (CCC), Bland-Altman plots and 95 % limit of agreement. Systematic bias was assessed using 95 % confidence interval of the mean difference.ResultsMean stride data demonstrated substantial agreement for stride length (CCC = 0.975) and stride velocity (CCC = 0.979) to almost perfect agreement for stride time (CCC > 0.996). Agreement between the technologies for individual stride-to-stride data remained high for stride time (CCC = 0.952); yet reduced for stride length (CCC = 0.868) and stride velocity (CCC = 0.877). Male/female differences in performance of the technology were observed for stride velocity, favouring females.SignificancePhysilog®5 inertial sensors accurately measure walking in adolescents, with stride time the most accurately detected parameter. This demonstrates that wearables can be used by researchers and clinicians working with adolescent groups as an alternative to fixed systems. These findings will ultimately pave the way to using wearables for assessments with children outside of the laboratory environment.     

Full length foot orthoses have an immediate treatment effect and modify gait of children with idiopathic toe walking

BackgroundThere remains a substantial lack of evidence to support the use of foot orthoses as a conservative treatment option for idiopathic toe walking (ITW). Encouraging heel contact during gait is one of the primary goals of most interventions in paediatric ITW.Research QuestionDoes the combined treatment of high-top boots and orthoses increase the number of heel contacts during gait and change spatio-temporal gait parameters?MethodsThis within subject designed randomised controlled trial recruited fifteen children diagnosed with ITW (n = 10 males). They were fitted with bilateral custom made rigid contoured carbon fibre foot orthoses placed inside high-top boots. To analyze the effect of this treatment, heel contacts and spatio-temporal parameters measured by an 8.3 m Gaitrite® mat were compared to barefoot walking and shod walking.ResultsAn immediate increase in heel contact (p = 0.021) was observed in the combined treatment only. Gait changes included a large increase in stride time in the combined treatment condition compared to barefoot walking (p = 0.006). This was associated with a decrease in the percentage of swing phase in the gait cycle (p < 0.010), an increase in stance phase (p < 0.010) and an increase in double support time (p < 0.001).SignificanceThese results suggest the hardness and thickness of the shoe and stiffness of the orthosis midsole may lead to improved local dynamic stability and foot position awareness with increased sensory feedback provided through the entire length of the foot. Further research is indicated to validate this treatment option on long term outcomes in this population group.     

Characterization of idiopathic Parkinson’s disease subgroups using quantitative gait analysis and corresponding subregional striatal uptake visualized using 18F-FP-CIT positron emission tomography

BackgroundGait disturbance is one of the most common symptoms among patients with idiopathic Parkinson’s disease (IPD). Nevertheless, Parkinson’s disease subtype clustering according to gait characteristics has not been thoroughly investigated.Research questionThe aim of this study was to identify subgroups according to gait pattern among patients with IPD.MethodsThis study included 88 patients with IPD who underwent ¹⁸F-fluorinated-N-3-fluoropropyl-2-β-carboxymethoxy-3-β-4-iodophenyl-nortropane positron emission tomography (¹⁸F-FP-CIT PET) and three-dimensional gait analysis (3DGA) between January 1, 2014 and December 31, 2016. We performed cluster analysis using temporal-spatial gait variables (gait speed, stride length, cadence, and step width) and divided patients into four subgroups. The kinematic and kinetic gait variables in 3DGA were compared among the four subgroups. Furthermore, we compared the uptake patterns of striatum among the four subgroups using ¹⁸F-FP-CIT PET.ResultsThe patients were clustered into subgroups based on gait hypokinesia and cadence compensation. Group 1 had decreased stride length compensating with increased cadence. Group 2 had decreased stride length without cadence compensation and wider step width. Group 3 had relatively spared stride length with decreased cadence. Group 4 had spared stride length and cadence. The uptake of posterior putamen was significantly decreased in Group 3 compared with Group 4.SignificanceGait hypokinesia and cadence can help to classify gait patterns in IPD patients. Our subgroups may reflect the different gait patterns in IPD patients.     

Ground reaction force and joint moment estimation during gait using an Azure Kinect-driven musculoskeletal modeling approach

BackgroundGait analysis is burdened by time and equipment costs, interpretation, and accessibility of three-dimensional motion analysis systems. Evidence suggests growing adoption of gait testing in the shift toward evidence-based medicine. Further developments addressing these barriers will aid its efficacy in clinical practice. Previous research aiming to develop gait analysis systems for kinetics estimation using the Kinect V2 have provided promising results yet modified approaches using the latest hardware may further aid kinetics estimation accuracyResearch questionCan a single Azure Kinect sensor combined with a musculoskeletal modeling approach provide kinetics estimations during gait similar to those obtained from marker-based systems with embedded force platforms?MethodsTen subjects were recruited to perform three walking trials at their normal speed. Trials were recorded using an eight-camera optoelectronic system with two embedded force plates and a single Azure Kinect sensor. Marker and depth data were both used to drive a musculoskeletal model using the AnyBody Modeling System. Predicted kinetics from the Azure Kinect-driven model, including ground reaction force (GRF) and joint moments, were compared to measured values using root meansquared error (RMSE), normalized RMSE, Pearson correlation, concordance correlation, and statistical parametric mappingResultsHigh to very high correlations were observed for anteroposterior GRF (ρ = 0.889), vertical GRF (ρ = 0.940), and sagittal hip (ρ = 0.805) and ankle (ρ = 0.876) moments. RMSEs were 1.2 ± 2.2 (%BW), 3.2 ± 5.7 (%BW), 0.7 ± 0.1.3 (%BWH), and 0.6 ± 1.0 (%BWH)SignificanceThe proposed approach using the Azure Kinect provided higher accuracy compared to previous studies using the Kinect V2 potentially due to improved foot tracking by the Azure Kinect. Future studies should seek to optimize ground contact parameters and focus on regions of error between predicted and measured kinetics highlighted currently for further improvements in kinetic estimations.     

The gait standard deviation,a single measure of kinematic variability

Measurement of gait kinematic variability provides relevant clinical information in certain conditions affecting the neuromotor control of movement. In this article, we present a measure of overall gait kinematic variability, GaitSD, based on combination of waveforms’ standard deviation. The waveform standard deviation is the common numerator in established indices of variability such as Kadaba's coefficient of multiple correlation or Winter's waveform coefficient of variation.Gait data were collected on typically developing children aged 6–17 years. Large number of strides was captured for each child, average 45 (SD: 11) for kinematics and 19 (SD: 5) for kinetics. We used a bootstrap procedure to determine the precision of GaitSD as a function of the number of strides processed. We compared the within-subject, stride-to-stride, variability with the, between-subject, variability of the normative pattern. Finally, we investigated the correlation between age and gait kinematic, kinetic and spatio-temporal variability.In typically developing children, the relative precision of GaitSD was 10% as soon as 6 strides were captured. As a comparison, spatio-temporal parameters required 30 strides to reach the same relative precision. The ratio stride-to-stride divided by normative pattern variability was smaller in kinematic variables (the smallest for pelvic tilt, 28%) than in kinetic and spatio-temporal variables (the largest for normalised stride length, 95%). GaitSD had a strong, negative correlation with age. We show that gait consistency may stabilise only at, or after, skeletal maturity.     

Inverse dynamics calculations during gait with restricted ground reaction force information from pressure insoles

The number of consecutive strides that can be recorded in measurements of gait have been limited due to the number of force plates and dimensions of the measurement field. In addition, the feet are constrained to land on the force plates. A method to calculate the inverse dynamics from the motion and incomplete information from the ground reaction forces (GRF), vertical component and its application point, is presented and compared to the calculations based on force plate measurements. This method is based on the estimation of the three-dimensional GRF during walking with pressure insoles. RMS errors were lower than 20 W for knee joint power compared to those derived from force plate measurements. The errors were larger during double stance phase due to errors in the application point measured with the insoles. This method, with some technical improvement, could be implemented in new gait analysis protocols measuring several consecutive steps either on a treadmill or over ground, depending on the motion-measurement system, without constraining foot placement.     

Effects of barefoot vs. shod walking during indoor and outdoor conditions in younger and older adults

BackgroundGait stability and variability measures in barefoot and shod locomotion are frequently investigated in younger but rarely in older adults. Moreover, most studies examine gait measures in laboratory settings instead of real-life settings.Research questionsHow are gait stability and variability parameters affected by footwear compared to barefoot walking in younger and older adults as well as under indoor vs. outdoor conditions?MethodsHealthy younger (<35 years) and older adults (>65 years) participated in the randomised within-subject study design. Participants conducted consecutive 25 m walking trials barefoot and with standardised footwear inside and outside. Inertial measurement units were mounted on the participant’s foot and used to calculate local dynamic stability (LDS), velocity and minimal toe clearance (MTC), stride length and stride time, including variabilities for these parameters. Linear mixed models were calculated.ResultsData of 32 younger (17 female, 15 male, age: 30 ± 4 years) and 42 older participants (24 female, 18 male, age: 71 ± 4 years) were analysed. MTC variability was higher in shod conditions compared to barefoot (p = 0.048) and in outdoor conditions (p < 0.001). LDS was different between age groups (p < 0.001). Gait velocity and MTC were higher in shod and outdoor conditions (both p < 0.001). Stride length and time were higher in shod conditions (both p < 0.001) and different between outdoor vs. indoor (longer stride length and shorter stride time outdoor, both (p < 0.001) as well as age groups (shorter stride length (p < 0.021) and stride time in older adults (p < 0.001).SignificanceResults suggest that gait stability and variability in older and younger adults are acutely affected by footwear vs. barefoot and indoor vs. outdoor walking conditions, indicating a high adaptiveness of these parameters to different experimental conditions. Consequently, future studies should be careful with generalising results obtained under certain conditions. Findings stress the clinical potential of barefoot walking.     

An electronic walkway can predict short-term fall risk in nursing home residents with dementia

ObjectivesTo evaluate the feasibility and validity of gait parameters measured with an electronic walkway system in predicting short-term fall risk in nursing home residents with dementia.Methods57 ambulatory nursing home residents with moderate to severe dementia participated in this prospective cohort study. We used the GAITRite^® 732 walkway system to assess gait parameters. Measurements were collected every 3 months over a 15 month period, with each measurement being a baseline for the subsequent measurement. Falls were retrieved from incident reports. The predictive validity of the GAITRite^® parameters was expressed in terms of sensitivity and specificity. Logistic regression analysis was conducted to examine the association between these parameters and falls occurrence within three months.ResultsReduced velocity (OR = 1.22; 95% CI 1.04–1.43) and reduced mean stride length (OR = 1.19; 95% CI 1.03–1.40) were the best significant gait predictors of a fall within three months, with a sensitivity of 82% for velocity and 86% for mean stride length, and a specificity of 52% for velocity and for mean stride length. The test procedure took an average of 5 min per participant. Some verbal persuasion or physical cueing was necessary in 142 measurements (80.7%).ConclusionGait parameters as measured with an electronic walkway system can be used for the prediction of short-term fall risk in nursing home residents with moderate to severe dementia. However some form of persuasion might be needed to perform the task. To refine our findings, large prospective studies on the predictive validity of gait parameters in this type of population are needed.     

What features of the built environment matter most for mobility? Using wearable sensors to capture real-time outdoor environment demand on gait performance

BackgroundA growing body of research has demonstrated relationships between built environment characteristics and outdoor mobility. However, most of this work has relied on composite scores of the built environment.Research questionWhich properties of the outdoor built environment are associated with the greatest change in gait metrics in a real-world setting?Methods25 community-dwelling adults from Southeast Michigan were equipped with mobile inertial measurement units and walked a 1300-meter outdoor course with varying environmental demands. Environmental properties were documented in sections of the course using the Senior Walking Environmental Assessment Tool. Gait speed, left foot cadence, and stride length were used to identify the built environment properties under which mobility was most challenged using linear mixed models. We hypothesized that subjects would adapt to demanding environments by decreasing gait speed, increasing cadence, and shortening stride length.ResultsProperties of the built environment were significantly associated with changes in gait speed, left foot cadence, and stride length. Properties that were most important for predicting gait speed included slope, sidewalk condition, and presence of holes. Sidewalk slope, bumps, and the presence of a curb cut were all significant predictors of left foot cadence. Mean stride length of the outdoor course was significantly associated with the section’s condition, slope, holes, bumps, width, and the presence of grooves and bumps at a curb.SignificanceAssociations between environmental properties and gait parameters were differential across the three mobility outcomes. When examining which properties of the built environment are challenging to navigate it is important to understand the relative influence of specific properties on gait metrics. Knowledge of which built environment properties are barriers for walking behavior is critical for the design of inclusive sidewalks and streets.