Variability Of Gait Parameters Research Articles

Outcome of ankle arthrodesis and total ankle replacement for ankle arthrosis in terms of gait variability

Background: Higher variability in gait parameters has been reported in patients’ with arthrosis of hip and knee joints, leading to dynamic instability and increased risk of falling. Higher variability and gait instability has also been noted to persist months after surgery. Ankle arthrosis is likely similar, but information regarding this is lacking. The purpose of the study was to evaluate gait variability following ankle arthrosis and its surgical treatments, ankle arthrodesis and total ankle replacement. Methods: Seventy participants, divided into controls, ankle arthrosis, ankle arthrodesis and total ankle replacement, performed gait assessment wearing 3-D inertial sensors through which gait parameters and the variability were compared among groups. Correlations between American Orthopedic Foot and Ankle score and Foot and Ankle Ability Measure score with the gait parameters and their variability were calculated. Results: All three case groups reported gait variability similar to that of the controls. On the contrary, significant differences (P < .01) were reported in several gait parameters when compared to the controls in all case groups. Furthermore, both clinical scores showed little to no correlation with gait variability and a good correlation was reported with gait parameters (P < .0001). Conclusions: The study did not find gait variability to be as reliable compared with gait parameters when assessing the outcome of ankle surgeries. Furthermore, among the gait parameters, walking speed showed a strong correlation with the patients’ functional status and is confirmed as an important parameter for ankle arthrosis.

The “butterfly diagram”: A gait marker for neurological and cerebellar impairment in people with multiple sclerosis

People with multiple sclerosis (PwMS) frequently experience walking and balance impairments. In our previous report, we demonstrated that spatio-temporal gait parameters, collected by the Zebris FDM-T instrumented treadmill (Zebris Medical GmbH, Germany), serve as valid markers of neurological impairment in the MS population. In the current study, we focused on a unique outcome statistic of the instrumented treadmill, the “butterfly” diagram which reflects the variability of the center of pressure trajectory during walking. Therefore, the aim of the study was to examine the relationship between parameters related to the gait butterfly diagram and the level of neurological impairment in PwMS. Specifically we examined whether the gait butterfly parameters can differentiate between MS patients with normal cerebellar function and those suffering from ataxia. Demographic, neurological and gait parameters were collected from 341 PwMS, 213 women, aged 42.3 (S.D.=13.8). MS participants with ataxia demonstrated higher scores relating to the butterfly gait variability parameters compared to PwMS with normal or slightly abnormal cerebellar function. According to the results of the binary regression analysis, gait variability in the ant-post direction was found to explain 18.1% of the variance related to cerebellar function; R2=0.181, χ2(1)=67.852, P<0.001. Measurements derived from the butterfly diagram are proper estimators for important neurological functions in PwMS and should be considered in order to improve diagnosis and assessment of the MS population.

Dual-tasking gait variability and cognition in late-life depression.

Studies have demonstrated an association between major depressive disorder (MDD) symptoms and fall risk in older adults, which may be at least partially mediated by executive functioning skills. There have also been observations of increased gait variability associated with fall risk and disease. This preliminary study first sought to understand whether gait variability in the context of dual task cost differs among older adults with MDD, relative to those with no history of psychiatric illness, and second, to identify relationships between gait variability measures and cognitive functioning in the context of MDD. We recruited 15 older adults with MDD and 17 non-depressed (ND) community-dwelling older adults. All participants had impaired balance based on unipedal stance time. Assessments included neuropsychological measures and measures of gait variability using an instrumented gait mat (GAITRite© ) in the context of dual task relative to single task performance (i.e., dual task cost). The groups did not differ on any gait variability parameters. The MDD group demonstrated poorer performance in the psychomotor speed domain, relative to the ND group, but cognitive functioning between the groups in other domains was equivalent. In MDD, increased variability in stride time, stride velocity, and swing time during dual-tasking were associated with poorer executive functioning and visual memory. In ND, no significant relationships between gait variables and cognitive performance were observed. Findings suggest that unique cognitive mechanisms underlie mobility problems associated with fall risk in late-life depression.

Experimental characterisation of walking locomotion on rigid level surfaces using motion capture system

Low-frequency structures, such as footbridges and long-span floors, are often sensitive to variations in dynamic loading induced by pedestrians. As a result, the design of these structures using traditional deterministic approaches is being replaced by stochastic load models that can accommodate different styles of walking. To inform development and facilitate wider implementation of the new stochastic approaches, a database of experimental data characterising both inter- and intra-subject variability of gait parameters is required. This study aims to contribute to the development of such a database by providing a set of data for walking over rigid level surfaces.The motion capture system Vicon was used for simultaneous monitoring of the kinematic and kinetic gait parameters. Ten test subjects walking at 13 different speeds participated in the experimental programme. Novel experimental data on pacing rate, step length, step width, angular positions of the legs and the trunk, and the force amplitude were collected and statistically characterised. The acquired data are suitable for calibration of the bipedal pedestrian models intended for civil engineering applications.

Assessing Gait Variability in Transtibial Amputee Fallers Based on Spatial-Temporal Gait Parameters Normalized for Walking Speed

ObjectiveTo determine whether normalizing spatial-temporal gait data for walking speed obtained from multiple walking trials leads to differences in gait variability parameters associated with a history of falling in people with transtibial amputations. DesignCross-sectional study. SettingRehabilitation center. ParticipantsPeople with unilateral transtibial amputations (N=45; mean age ± SD, 60.5±13.7y; 35 men [78%]) were recruited. InterventionsNot applicable. Main Outcome MeasuresParticipants completed 10 consecutive walking trials using an instrumented walkway system. Primary gait parameters were walking speed and step-length, step-width, step-time, and swing-time variability. A retrospective 12-month fall history was obtained from participants. ResultsSixteen amputees (36%) were classified as fallers. Variation in gait speed across the 10 walking trials was 2.9% (range, 1.1%–12.1%). Variability parameters of normalized gait data were significantly different from variability parameters of nonnormalized data (all P<.01). For nonnormalized data, fallers had greater amputated limb step-time (P=.02), step-length (P=.02), swing-time (P=.05), and step-width (P=.03) variability and nonamputated limb step-length (P=.04) and step-width (P=.01) variability. For normalized data, only 3 variability parameters were significantly greater for fallers. These were amputated limb step-time (P=.05), step-length (P=.02), and step-width (P=.01) variability. ConclusionsNormalizing spatial-temporal gait data for walking speed before calculating gait variability parameters may aid in discerning variability parameters related to falls histories in people with transtibial amputations. This may help focus on the initial rehabilitation efforts of amputees with a fall history.

Can stability really predict an impending slip-related fall among older adults?

The primary purpose of this study was to systematically evaluate and compare the predictive power of falls for a battery of stability indices, obtained during normal walking among community-dwelling older adults. One hundred and eighty seven community-dwelling older adults participated in the study. After walking regularly for 20 strides on a walkway, participants were subjected to an unannounced slip during gait under the protection of a safety harness. Full body kinematics and kinetics were monitored during walking using a motion capture system synchronized with force plates. Stability variables, including feasible-stability-region measurement, margin of stability, the maximum Floquet multiplier, the Lyapunov exponents (short- and long-term), and the variability of gait parameters (including the step length, step width, and step time), were calculated for each subject. Sensitivity of predicting slip outcome (fall vs. recovery) was examined for each stability variable using logistic regression. Results showed that the feasible-stability-region measurement predicted fall incidence among these subjects with the highest sensitivity (68.4%). Except for the step width (with an sensitivity of 60.2%), no other stability variables could differentiate fallers from those who did not fall for the sample included in this study. The findings from the present study could provide guidance to identify individuals at increased risk of falling using the feasible-stability-region measurement or variability of the step width.

Assessment of Gait Variability: Towards an Optimal Testing Protocol

Gait variability is frequently used to identify rehabilitation progresses in orthopedic and neurologic diseases by means of repeated testing. However, learning effects are a significant issue. This study examined if the inter-day reliability of gait variability parameters improves with an additional familiarization trial.

Muscle activity during stance phase of walking: Comparison of males with transfemoral amputation with osseointegrated fixations to nondisabled male volunteers

A recent development in prosthetics is the osseointegrated fixation (OF), with improvements in comfort, fatigue, hip movement, and ease of prosthetic attachment reported. However, little information is available regarding muscle function. This study reports on selected gait parameters of the residual limb during the stance phase of level overground walking, focusing on muscle activity. Five males with transfemoral amputation (TFA) with OFs were recruited. Ground reaction force (GRF), lower-limb kinematics, and surface electromyography (sEMG) from residual-limb muscles were recorded. sEMG data were also collected from a group of 10 nondisabled male subjects. Interstance variability of gait parameters was assessed by coefficient of multiple correlations. Repeatability of GRF and hip kinematics was high, whereas repeatability of the sEMG was low for four of the five individuals with TFA. Interstance variability of the sEMG for gluteus medius (GMED) was significantly greater in the group with TFA. The main difference in sEMG between the groups was the phase, with GMED and adductor magnus displaying greater differences than their counterparts in the nondisabled group. Results demonstrate that muscles in the residual limb retain aspects of their previous functional pattern.

Reliability of gait parameters during treadmill walking in community-dwelling healthy seniors

The present study aimed at assessing the between- and within-day-variability of temporal and spatial gait characteristics during treadmill walking in community-dwelling seniors. In 20 active, healthy seniors (10 women, 10 men, age: 64.8 (SD 3.2) years, height: 1.70 (0.10)m, weight: 69.7 (10.9)kg, physical activity: 11 (6)hweek−1) gait characteristics were assessed on three days in weekly intervals (between-day variability). Either on days two or three, testing was repeated 30min after the initial trial (within-day variability). We determined routine spatio-temporal gait parameters as well as gait variability during 400 steps at a normal walking speed (5.0 (0.4)kmh−1) on a one-dimensional ground reaction force measuring treadmill. No significant mean differences occurred in any parameter for between- and within-day comparisons. Between-day ICC were high (ICC≥0.86) for most parameters except for temporal (ICC=0.44) and spatial (ICC=0.22) gait variability. Coefficients of variation (CoV) were also high in the latter parameters (CoV=30.2–36.1%), whereas all other variables showed clearly lower values (CoV<7%). CoV were still lower between days 2 and 3 (CoV<5%). Compared to between-day comparisons, within-day variability was comparable in spatio-temporal gait parameters (CoV<5%, ICC≥0.97) and lower in gait variability parameters (CoV<18%, ICC≥0.72–0.74). In conclusion, most gait parameters were highly reliable during treadmill walking. Changes of less than 10% can be detected with sufficient confidence. Gait variability parameters were less reliable and, thus, should be carefully interpreted.

A térdízületi protézis hatása a járás változékonyságára a korai posztoperatív szakaszban különböző feltárások esetén

A térdízületi protézis hatása a járás változékonyságára a korai posztoperatív szakaszban különböző feltárások esetén

Importance of correcting for individual differences in the clinical diagnosis of gait disorders

ObjectiveTo quantify the effects of subject characteristics on gait parameters using acceleration-based gait analysis. DesignCross-sectional study with a single group cohort. SettingHospital setting. ParticipantsOne hundred and twenty healthy subjects (six age decade groups of 10 men and 10 women) performed a 20-m walking test. MethodsBasic gait parameters (e.g. speed) and other clinically relevant parameters (e.g. step time asymmetry) were assessed during a 20-m walking test using a tri-axial accelerometer, attached at the level of the sacrum. Subject characteristics were recorded. ResultsBetween 34% and 51% of the variability in gait parameters was explained by age, height and gender. Subject characteristics contributed less to the variance in step time asymmetry (R2=0.02), gait irregularity (R2=0.07) and vertical displacement of the centre of mass (R2=0.17). Relationships identified were comparable with previous studies (e.g. faster walking speed in men, younger and taller subjects). ConclusionsAge, height and gender are determinants of basic gait parameters, while their influence on gait irregularity and step time asymmetry is minimal. This indicates that gait is variable between subjects, showing the relevance of correcting gait for subject characteristics. This study describes preliminary work to build a database of gait parameters in healthy participants, describing the effects of age, gender and height. Further studies to extend this database with patients would provide further relevance to clinical practice.

Effect of severity of knee osteoarthritis on the variability of gait parameters

Gait analysis has provided important information concerning gait patterns and variability of gait in patients with knee osteoarthritis (OA) of varying severity. The objective of this study was to clarify how the variability of gait parameters is influenced by the severity of knee OA. Gait analysis was performed at three different controlled walking speeds in three groups of subjects with varying degrees of knee OA (20 healthy subjects with no OA and 90 patients with moderate or severe OA). The variability of gait parameters was characterized by the coefficient of variance (CV) of spatial-temporal parameters, as well as by the mean coefficient variance (MeanCV) of angular parameters. Based on our results, we conclude that the complexity of gait decreases if the walking speed differs from the self-selected speed. In patients with knee OA, the decreased variability of angular parameters on the affected side represents decreased joint flexibility. This leads to decreased consistency in movements of the lower limbs from stride-to-stride, as shown by increased variability of spatial-temporal parameters. Decreased joint flexibility and consistency of movement can be associated with decreased complexity of movement. Other joints of the kinetic chain, such as joints of the non-affected side and the pelvis, play an important role in compensation and adaptation of step-by step motion and in the ability of secure gait. Results suggest that the variability of gait associated with knee osteoarthritis is gender-dependent. During rehabilitation, particular attention must be paid to improving gait stability and proprioception and gender differences should be taken into account.

The influence of medial meniscus injury and meniscectomy on the variability of gait parameters

Degenerative and biomechanical changes in the knee joint after partial medial arthroscopic meniscectomy are well known. However, no studies have assessed the variability of gait parameters before and after partial medial meniscectomy. The goal of this research was (1) to determine the variability of gait parameters at different speeds before and after meniscectomy and (2) to compare this variability to that of healthy controls. The variability of spatial-temporal parameters was characterized by a coefficient of variance (CV), the percentage ratio of standard deviation and mean; on the other hand, the variability of angular parameters was characterized by a mean coefficient of variance (Mean CV), which is the average coefficient variance over all integer percents of normalized gait cycles. The spatial positions of the anatomical points for calculating gait parameters were determined in 20 young healthy controls and 20 patients preoperatively and 3 and 12 months after meniscectomy. Gait speed significantly influenced the CV of spatial-temporal parameters and the Mean CV of angular parameters. Gait parameter variability showed significant changes in patients prior to and 3 months after the partial medial meniscectomy compared to the healthy group. The variability of angular parameters still differed from the healthy group 12 months postoperatively. The complexity of gait decreased if the walking speed differed from the self-selected speed. Prior to and after meniscectomy, the decreased variability of angular parameters on the affected side of patients represented decreased flexibility of joints. This led to decreased consistency in movements of the lower limbs from stride to stride, as shown by the increased variability of spatial-temporal parameters. A decrease in joint flexibility and consistency of movement can be associated with a decreased complexity of movement. Preoperatively and postoperatively, patients used the non-affected limb and pelvis obliquity for compensation to help stabilize their gait.

Variability of Gait Parameters in Different Daily Situations

Gait parameters of ten subjects were recorded in Human Motion Analysis Laboratory at Technical University of Kosice to provide data for gait pattern study. Subjects were walking by their self-selected walking speed and accelerated speed of walking in 3 different situations differing with type of cloths. System SMART was used to capture 3D coordinates of subjects' movement (6 infrared cameras, 50Hz) for each specific situation and different speed. The motion data available immediately after 3D gait data reconstruction in SMART Tracker software were time dependent position, velocity and acceleration of 25 markers. They provided input for further calculation and kinematic data analysis of human gait. The data analysis conducted in program SMART analyzer provides an overview about gait parameters variability in frame of investigated group of pendants.

Gait parameters and stride-to-stride variability during familiarization to walking on a split-belt treadmill

Background Subjects unfamiliar to walking on a split-belt treadmill may initially demonstrate an altered gait pattern or increased variability of gait parameters. While previous investigations have examined kinematic variables associated with familiarization time, the objective of this study was to determine the familiarization period required to obtain the most reproducible gait pattern through the assessment of kinetic, kinematic and spatio-temporal parameters during a single session of treadmill walking. Methods Eleven healthy subjects participated in a single bout of treadmill walking which lasted 9 min. Kinematic and kinetic data were collected from the first 30 s of each minute, beginning when the treadmill reached full speed. Means and standard deviations for knee flexion at heel strike, ground reaction forces, step width and step length were obtained to examine the changes in each variable over the 9 min. Mean r 2 values were evaluated for changes in variability from one stride to the subsequent stride for sagittal plane hip, knee and ankle joint angles and moments, as well as for vertical and horizontal ground reaction forces. Findings Significant reductions in variability were found for vertical and horizontal ground reaction forces, knee flexion at heel strike and step length over 9 min. Only step width showed a change in the mean value across trials. There were no increases in r 2 values after the 5th min for any of the gait variables. Interpretation The results suggest that in order to collect accurate data for gait analysis, subjects should be familiarized to the split-belt treadmill for at least 5 min prior to data collection.

Poster 18: The Effects of Assistive Devices on Gait Measures in Huntington's Disease

Introduction Falls are frequent in individuals with Huntington's disease (HD), due to gait and balance impairments. Falls often occur when turning, or when maneuvering in tight spaces and around obstacles when walking. Methods This study examined the effect of 8 different ambulatory assistive devices (ADs, e.g., canes, walkers) on spatiotemporal gait measures as measured with GaitRite in 21 individuals with HD. Subjects also walked in a figure-of-eight around two chairs placed four feet apart. Results During gait without an AD, we found high variability in gait parameters (stride time percent coefficient of variation [%CV] = 12.92, swing time %CV = 7.80, and double support time %CV = 24.61). Preliminary results indicate that a four-wheeled walker (4ww) induced more normal gait parameters (e.g., higher mean velocity and step length and lower support base, percent of gait cycle in double stance, and step variability) compared to a standard walker (Sw) and cane; more pronounced gait deficits occurred with a Sw. During figure-of-eight maneuvers, subjects moved significantly faster (p Conclusions Individuals with HD may have difficulty using Sws and canes because the task complexity and demands on balance are greater than with the 4ww. Wheeled walkers produce more efficient gait patterns than no assistive device, canes, or Sws in individuals with HD and may be the best assistive device for fall prevention in individuals with HD. This study also demonstrated that utilizing walking in a figure-of-eight around obstacles is a sensitive test of dynamic balance function.

Effect of compensation procedures for velocity on repeatability and variability of gait parameters in normal subjects

Objective: To evaluate the effects of a mathematical procedure that adjusts for gait velocity on the variability seen in gait analysis. Design: Evaluation before and after compensation. Setting: Gait laboratory, Fukui University Hospital, Japan. Subjects: Fourteen normal volunteers. Outcome measures: A computerized gait analysis system with two forceplates and a light source spot measuring device was used. Gait measurement in each subject was performed on three different days. Results: The gait parameters measured on three different days were significantly different, particularly step length, stride length, velocity, the components of floor-reaction forces and hip motion. In these parameters, intraclass correlation coefficient, ICC (1,1) was not high (range 0.05-0.71). However, there was a high correlation between these parameters and velocity and high repeatability was obtained following compensation for velocity (ICC (1,1), range 0.73-0.97). In contrast, compensation of parameters whose measurement was not significantly different before compensation did not improve ICC (1,1). Variability of all parameters was acceptable, however CV (an index of variability) improved significantly after compensation compared with that before compensation in six of 15 parameters. Conclusions: Our findings suggest that low repeatability in gait parameters should be considered even when the gait of normal subjects is measured on different days. A high repeatability and more acceptable variability were obtained when the data were compensated for velocity.