Quantitative analysis of gait in Parkinson's disease: a pilot study on the effects of bilateral sub-thalamic stimulation

Four patients with Parkinson's disease who had a Subthalamic Nucleus (STN) stimulator implanted and four age-matched controls underwent gait analysis using a three-dimensional system. STN stimulation substantially improved most of the key variables in the patients, without producing inefficient compensatory movements of the trunk. A reduction of ankle power production during push off was the most persistent abnormality seen when the patients were stimulated. We also found a reduction of trunk lateral bending and torsion when the patients were not stimulated when compared with controls.     

Evaluation of a visual feedback system in gait retraining: a pilot study

Abnormal gait pattern of the frontal plane (i.e. Duchenne gait and Trendelenburg gait) may be caused by a variety of diseases. The aim of this pilot study was to evaluate the instantaneous effect of a visual feedback system on frontal plane pelvis and trunk movements in order to use it in patients with THR in subsequent studies. A total of 24 women (45-65 years) were included in the study. According to acute functional impairments the subjects were assigned to the control group (CG, no gait disorders, n=15, age=59±11 years, BMI=27±4) or to the intervention group (IG, n=9, age=61±4, BMI=29±5), respectively. First, in Measurement 1 (M1) kinematic reference values were captured in a standardized clinical gait analysis (MVN, XSens). Afterwards, the influence of a visual real-time feedback on gait pattern was examined while using the feedback system (M2). While there was a significant difference of IG vs. CG in M1 in the mean inclination regarding pelvis and trunk movements, this was not detected in M2. Therefore it is concluded, especially in subjects with abnormal gait pattern, that the visualization leads to an improvement of the movement pattern of pelvis and trunk in the frontal plane while using the device.     

The energetic cost of gait retraining: A pilot study of the acute effect

ObjectiveTo investigate the acute effect of gait retraining aimed at reducing tibial peak positive acceleration (PPA) on energetic cost (VO₂).DesignIntervention with a pre/post-test design.SettingUniversity biomechanics laboratory.Participants12 healthy male runners (23.4 ± 5.3 years, 179.7 ± 4.3 cm, 75.6 ± 9.2 kg).Main outcome measuresTibial PPA and oxygen consumption (VO₂) were measured after a five minute baseline run and at the end of a gait retraining session aimed at minimizing tibial PPA.ResultsTibial PPA significantly decreased between baseline and after gait retraining (32.6%, p = 0.007). VO₂ significantly increased between the two time periods (9.3%, p = 0.008). There was no correlation between change in tibial PPA and change in VO₂ (p = 0.956, r = 0.018).ConclusionPractitioners who aim to reduce injury risk by minimizing tibial PPA in runners need to consider the possible acute effect on performance as a result of changes in VO₂. Further investigation is warranted to understand the energetic cost of different kinematic strategies used by individuals.     

Longitudinal gait and balance decline in Friedreich’s Ataxia: A pilot study

IntroductionFriedreich’s Ataxia (FA) is a devastating, progressive, neurodegenerative disease. Objective measures that detect changes in neurological function in FA patients are needed to facilitate therapeutic clinical trials. The purpose of this pilot study was to analyze longitudinal changes in gait and balance in subjects with FA using the GAITRite Walkway System® and Biodex Balance System™, respectively, and to test the ability of these measures to detect change over time compared to the Friedreich’s Ataxia Rating Scale (FARS).MethodsThis was a 24-month longitudinal study comparing ambulatory FA subjects with age- and gender-matched, healthy controls. Eight FA subjects and 8 controls were tested at regular intervals using the GAITRite and Biodex Balance systems and the FARS.ResultsIn the FA group, comfortable and fast gait velocity declined 8.0% and 13.9% after 12 months and 24.1% and 30.3% after 24 months, respectively. Postural stability indices increased in FA subjects an average of 41% from baseline to 24 months, representing a decline in balance. Subjects with FA also demonstrated a 17.7% increase in FARS neurological exam scores over 24 months. There were no changes in gait or balance variables in controls. In the FA group, multiple gait and balance measures correlated significantly with FARS neurological exam scores.ConclusionsThe GAITRite and Biodex Balance systems provided objective and clinically relevant measures of functional decline in subjects with FA that correlated significantly with performance measures in the FARS. Gait velocity may be an important objective measure to identify disease progression in adults with FA.     

Comparison of underwater gait training and overground gait training for improving the walking and balancing ability of patients with severe hemiplegic stroke: A randomized controlled pilot trial

BackgroundWalking training is an essential intervention to improve the function in stroke patients. However, only a limited number of gait training strategies are available for stroke patients with relatively severe disabilities.Research questionIs underwater gait training or overground gait training more effective in severe stroke patients?MethodsA total of 21 patients with severe hemiplegic stroke were randomly assigned to the experimental and control groups. All participants (n = 21) received 60-minute sessions of general physical therapy, 5 times a week for a period of 12 weeks. Additionally, the experimental and control groups underwent underwater and overground walking training, respectively, for 30 min twice times a week for 12 weeks. Postural assessment for stroke score, center of pressure path length and velocity, step time and step length difference, and walking velocity were measured before and after the 12-week training.ResultsBoth groups showed a significant decrease in the center of pressure path length and velocity after the intervention compared to the values before the intervention (p < .05). However, there was no significant difference in the center of pressure path length and velocity changes after training between the two groups (p > .05). In the walking variables, the step length difference changes after training between the two groups showed a significant difference (p < .05). In the experimental group, the step length difference increased after the intervention compared to that before the intervention (+4.55 cm), whereas that of the control group decreased (-1.25 cm).SignificanceIn severe stroke patients, underwater gait training can be effective for improving balancing ability, but it may be less effective on the improvement of gait function than overground walking.Clinical trial registration number: KCT0002587 (https://cris.nih.go.kr)     

Different cognitive functions discriminate gait performance in younger and older women: A pilot study

AimCognitive dysfunction is associated with slower gait speed in older women, but whether cognitive function affects gait performance earlier in life has yet to be investigated. Thus, the objective of this study was to test the hypothesis that cognitive function will discriminate gait performance in healthy younger women.MethodsFast-pace and dual-task gait speed were measured in 30 young to middle-aged (30–45 y) and 26 older (61–80 y) women without mild cognitive impairment. Visuoperceptual ability, working memory, executive function, and learning ability were assessed using neuropsychological tests. Within each age group, women were divided by the median into lower and higher cognitive function groups to compare gait performance.ResultsYounger women with higher visuoperceptual ability had faster fast-pace (2.25 ± 0.30 vs. 1.98 ± 0.18 m/s, p ≤ 0.01) and dual-task gait speed (2.02 ± 0.27 vs. 1.69 ± 0.25 m/s, p ≤ 0.01) than women with lower visuoperceptual ability. The difference in dual-task gait speed remained significant (p = 0.02) after adjusting for age, years of education, and other covariates. Dividing younger women based on other cognitive domains showed no difference in gait performance. In contrast, working memory and executive function discriminated dual-task gait speed (p < 0.05) in older women after adjusting for age and education.ConclusionTo our knowledge, this is the first study to show that poorer cognitive function even at a relatively young age can negatively impact mobility. Different cognitive functions discriminated gait performance based on age, highlighting a possible influence of aging in the relationship between cognitive function and mobility in women.     

Age-related differences in interlimb coordination during typical gait: An observational study

BackgroundArm movements during gait are known to alter with increasing age during the slow maturation phase (>3years). It is unclear whether coordination between the arms and legs (i.e. interlimb coordination), which is a measure of gait quality, shows a similar pattern.Research Questionto investigate age-related differences in interlimb coordination during gait in typically developing children and adults.MethodsIn this observational study, 98 typically developing participants were divided into five age-groups: preschool children (G1; 2.9–5.9 years[n = 18]), children (G2; 6.0–9.9 years[n = 22]), pubertal children (G3; 10.0–13.9 years[n = 26]), adolescents (G4; 14.0–18.9 years[n = 14]) and adults (G5; 19.0–35.2 years[n = 18]). Participants walked barefoot at a self-selected walking speed along a 10-m walkway during three-dimensional total-body gait analysis. To examine interlimb coordination, mean continuous relative phase over the gait cycle (MRP) and its variability (sdMRP) were calculated for each combination of limb pairs in the sagittal plane.ResultsMRP increased towards more anti-phase coordination with increasing age in following limb pair combinations: left arm-right arm (median[interquartile range]; G1: 152.0°[126.6;160.7°]-G5: 171.5°[170.0;175.3°]), left arm-left leg (G1: 155.0°[131.3;167.6°]-G5: 170.8°[165.3;173.5°]) and right arm-right leg (G1: 155.7°[135.5;166.0°]-G5: 170.0°[166.4;173.5°]). MRP decreased towards more in-phase coordination from G1 to G5 in left arm-right leg (G1: 24.4°[15.3;45.8°]-G5: 10.5°[6.1;15.6°]) and right arm-left leg (G1: 25.0°[13.7;41.1°]-G5: 9.7°[5.2;16.8°]). sdMRP decreased from G1 to G5 for all limb pair combinations.SignificanceInterlimb coordination altered with increasing age. First, coordination between the legs and right arm-left leg appeared mature in G1 (aged 2.9−5.9 years). Next, coordination between the ipsilateral limbs seemed mature at 9.9 years, followed by a mature coordination between left arm-right leg at 13.9years. Coordination between the two arms showed ongoing differences until adulthood. These data provide an age-related framework and normative dataset to distinguish age-related differences from pathology in children with neuromotor disorders in clinical practice.     

The effect of tactile feedback on gait initiation in people with Parkinson's disease: A pilot study

BackgroundGait initiation and turning are common triggers for Freezing of Gait (FOG) in people with Parkinson’s disease (PD). Recently, it has been shown that closed-loop tactile feedback (CLTF) can be effective to improve turning performance in people with FOG.Research questionDoes CLTF change the preparation and execution of the first step during gait initiation?MethodsPeople (n = 36) with PD with FOG (PD + FOG) (n = 18) and without FOG (PD-FOG) (n = 18) were included in the study and performed self-initiated gait with or without CLTF under single and dual task conditions. Anticipatory postural adjustments (APAs) and step kinematics were quantified with inertial measurement units (IMUs). Muscle activity of the right and left tensor fasciae latae (TFL) was measured via EMG recordings.ResultsPD + FOG and PD-FOG did not differ in age, gender and disease duration and severity (p > 0.05). PD + FOG performed smaller APAs (F = 4.559, p = 0.04) with a higher amount of TFL co-contraction (F = 6.034, p = 0.02) compared to PD-FOG. CLTF had no effect on APAs but led to an increase in first step duration (F = 7.921, p = 0.008).ConclusionsPD + FOG had smaller APAs and higher left and right TFL co-contraction during gait initiation. CLTF did not impact preparation of the first step but led to a slower execution of the first step. We speculate that, similarly to findings from turning, CLTF might result in the participant attending more closely to the first step compared to without CLTF. Whether increased attention on gait initiation is beneficial in diminishing FOG should be investigated in more detail.     

Comparable walking gait performance during executive and non-executive cognitive dual-tasks in chronic stroke: A pilot study

BackgroundFalls are a serious problem among stroke survivors due to subsequent injuries, recovery setbacks, dependence, and mortality. A growing body of dual-task (DT) studies suggests a role of executive functions in gait control and falls, particularly in subacute stroke. However, few studies have compared distinct executive and non-executive tasks, nor their effects on chronic stroke gait. Research question: The purpose of this cross-sectional study was to compare the effects of distinct working memory (2-back) and inhibition (Stroop) tasks on walking gait performance in chronic stroke survivors.MethodsA pilot sample of chronic stroke survivors (n = 11, 8 males, mean age = 70.91, 6-12months post-stroke event) and age-matched healthy controls (n = 13, 4 male; mean age = 68.46) were tested. Gait performance (speed, stride time, stride time variability, stride length and stride length variability) was measured using 2 wireless inertial measurement sensors under 4 walking conditions: 1) preferred walking (single-task: ST), 2) walking with a 2-back DT, 3) walking with a Stroop DT, and 4) walking with a non-executive motor response DT. The secondary tasks were also carried out in both ST (seated) and DT conditions, to examine bidirectional effects.ResultsWhile the stroke survivor sample had a slower gait speed across conditions and tasks, there were no significant differences between the groups [F(1, 22) = 1.13, p =.299, η²p = .049] on the spatial or temporal gait characteristics recorded: gait performance was maintained during executive and non-executive DTs. In addition, we did not find a significant effect of group on cognitive task performance (all p > .052). However, we observed a cost in accuracy on the 2-back DT for both groups, suggesting resource overlap and greater cognitive load (all t > 19.72, all p < .001).SignificanceOur gait data contradict previous studies evidencing impaired gait post-stroke, suggesting functional recovery in this chronic stroke sample.     

Interpreting sources of variation in clinical gait analysis: A case study

ObjectiveTo illustrate and discuss sources of gait deviations (experimental, genuine and intentional) during a gait analysis and how these deviations inform clinical decision making.MethodsA case study of a 24-year old male diagnosed with Alkaptonuria undergoing a routine gait analysis. A 3D motion capture with the Helen-Hayes marker set was used to quantify lower-limb joint kinematics during barefoot walking along a 10 m walkway at a self-selected pace. Additional 2D video data were recorded in the sagittal and frontal plane. The patient reported no aches or pains in any joint and described his lifestyle as active.ResultsTemporal-spatial parameters were within normal ranges for his age and sex. Three sources of gait deviations were identified; the posteriorly rotated pelvis was due to an experimental error and marker misplacement, the increased rotation of the pelvis in the horizontal plane was genuine and observed in both 3D gait curves and in 2D video analysis, finally the inconsistency in knee flexion/extension combined with a seemingly innocuous interest in the consequences of abnormal gait suggested an intentional gait deviation.ConclusionsGait analysis is an important analytical tool in the management of a variety of conditions that negatively impact on movement. Experienced gait analysts have the ability to recognise genuine gait adaptations that forms part of the decision-making process for that patient. However, their role also necessitates the ability to identify and correct for experimental errors and critically evaluate when a deviation may not be genuine.     

Assessing gait efficacy in older adults: An analysis using item response theory

BackgroundAssessing confidence in walking in older adults is important, as mobility is a critical aspect of independence and function, and self-report provides complementary information to performance-based measures. The modified Gait Efficacy Scale (mGES) is a self-report measure used to examine confidence in walking.Research Question: What are the psychometric properties of the mGES at the item level? Are there opportunities for improvement?MethodsWe performed a secondary analysis of baseline data from a cluster randomized trial of 424 community-dwelling older adults and reliability data from 123 participants. We fitted a graded response model to dissect the mGES to the item and individual response level and examined opportunities to improve and possible shorten the mGES. We examined psychometric characteristics such as internal consistency, test-retest reliability and construct validity with respect to other relevant measures.ResultsMobility tasks such as navigating stairs and curbs with separate items for going up and down largely provide the same information on confidence, with downward direction providing slightly more. It may be reasonable to consider removal of walking 1/2 mile, stepping down and/or stair tasks with railings items due to little or duplicate information contributed compared to other items. The shortened scales proposed by removing the above items had similar psychometric properties to mGES.SignificanceThe mGES has good psychometric properties, but can be potentially shortened to substantially reduce responder burden. The upward direction curb and stairs items can be removed to result in a 7-item scale with virtually no loss of desirable psychometrics. An alternative 3-item version, level surface walking, stepping down curb and climbing up stairs without a railing items, entails only a minimal loss in psychometric properties.     

Impact of destination-based visual cues on gait characteristics among adults over 75 years old: A pilot study

BackgroundVisual information is a contributing factor affecting human gait and balance, especially in low lit environments. To mitigate the adverse effects of poor lighting conditions and help older adults perceive their positions in a community-dwelling setting, destination-based visual perceptual cues were designed as a specific lighting intervention and the effectiveness of the lighting intervention was tested in this study.Research Questions1) Does the designed lighting intervention improve older adults’ walking performance? 2) Does the designed lighting intervention change older adults’ walking strategy?MethodsFifteen community-dwelling older adults (165.5 ± 9.3 cm, 6 males, 9 females) were recruited. Participants were instructed to walk from their bed to the bathroom repeatedly in two lighting conditions, their usual nightlight condition and a novel LED strip lighting condition. Human motion patterns, including walking performance, lower-limb kinematics, and trunk motions, were recorded and analyzed. To investigate the effect of visual cues on walking behaviors, one-way analysis of variance (ANOVA) were performed with lighting conditions as the within-subject factor.ResultsDestination-based visual perceptual cues induced less walking time among adults over 75 years old, compared to the usual nightlight condition. The decrease in walking time was accompanied by changes in other walking behaviors, including decreased hip flexion, increased ankle flexion, larger trunk planar acceleration RMS, and smoother trunk log dimensionless jerk.SignificanceThis study demonstrated the effectiveness of the designed lighting intervention upon the changes in older adults’ walking performance and strategies. With the help of destination-based visual perceptual cues, the older adults spent a shorter period of time walking to their destination (i.e., walking faster), with an improvement in their walking strategies, such as mitigated lower-body biomechanical plasticity and smoother trunk movement.     

Ankle dorsiflexors and plantarflexors neuromuscular electrical stimulation training impacts gait kinematics in older adults: A pilot study

BackgroundWhile ankle muscles, highly affected by aging, are highly implicated in the changes in gait kinematics and involved in the limitation of seniors' mobility, whether neuromuscular electrical stimulation (NMES) training of these muscles could impact gait kinematics in older adults has not been investigated yet.Research questionWhat are the effects of 12 weeks of ankle plantar and dorsiflexors NMES training on strength and gait kinematics in healthy older adults?MethodsFourteen older adults (73.6 ± 4.9 years) performed a three-time per week, three months long NMES training of both ankle plantar and dorsiflexors. Before and after training, neuromuscular parameters, gait kinematic parameters, and daily physical activity were measured.ResultsThe participants significantly increased their lower limb muscle mass and their plantar and dorsiflexors isometric strength after training. They reduced the hip abduction/adduction and the pelvic anterior tilt range of motion and variability during gait. However, the participants became less active after the training.SignificanceNMES training of ankle muscles, by increasing ankle muscle mass and strength,modified gait kinematics. NMES training of ankle muscles is feasible and effective to lower the hip implication and increment foot progression angle during gait. Further study should determine if this could lower the risk of falling.     

The effect of induced joint restriction on plantar pressure during gait – a pilot study

BackgroundThe aim of this study was to analyse the effect of induced lower limb joint restriction on plantar pressures during gait. Focusing on restricting a single joint, without the effect of other co-morbidities, would provide better understanding as to the resultant plantar loadings during gait, which would be especially beneficial in patients requiring offloading procedures.Research QuestionDoes induced lower limb joint restriction affect plantar pressure distribution during gait?MethodsA prospective, quasi-experimental study was conducted, recruiting ten healthy, adult participants who were instructed to walk barefoot over a Tekscan HR Mat™. This procedure was repeated after separately inducing restriction of the hip, knee and ankle joints. Mean peak plantar pressure (MPP) and pressure-time integral (PTI) data were analysed to compare between unrestricted and restricted data.ResultsSignificant plantar pressure changes were observed in the heel and first metatarsal regions. Rearfoot PTIs were increased with restriction of the contralateral hip (left p <0.001) (right p =0.02) and knee joints (left p =0.01) (right p =0.04). Both MPPs (left p =0.01; right p =0.01) and PTIs (left p =0.004; right p =0.03) were increased in the first metatarsal when restricting the hip joint of the same limb. MPP was decreased in the left first metatarsal with induced knee (left p =0.01; right p =0.04) and ankle (left and right p <0.001) joint restriction. Finally, MPP was decreased in the right first metatarsal with knee (left and right p =0.01) and ankle (left p =0.04; right p =0.01) joint restriction.SignificanceLimited joint mobility may have a direct effect on plantar pressure, particularly with restriction in the hip and knee joints, hence careful attention should be given especially in patients with conditions involving plantar loadings. Results in this study also show that PTI changes during gait should be equally evaluated clinically along with peak plantar pressure analysis.     

The effects of word length, articulation, oral-motor movement, and lexicality on gait: a pilot study

Previous research has suggested that articulatory demands are important predictors of the impact of dual-task interference on spatial-temporal parameters of gait. In this study, we evaluated the effects of word length, oral-motor movement, articulation, and lexicality, within a verbal task, on a continuous gait task. Fifteen healthy young women participated in a study in which two word lengths (monosyllabic and bisyllabic) were crossed with four levels of secondary task complexity (no dual-task, non-speech movement, spoken non-word, and spoken word). Spatial and temporal parameters of gait were measured using a 23' instrumented carpet. Results indicated a significant multivariate main effect for task type, F(15, 120)=3.07, that explained 71.1% of the demonstrated variability in gait. Univariate analyses of this main effect revealed statistically significant effects for velocity, step time, swing time, and stance time, but no statistically significant effect for step length. Post hoc analyses suggested that dual-task interference produced significant changes in the parameters of gait, but that this interference was not significantly greater with non-words as compared to the non-speech movement condition, nor was it significantly greater with words as compared to non-words. The results of this systematic deconstruction of a simple verbal task suggest that the motor component of a secondary speech task may produce the largest amount of interference within a dual-task interference paradigm.