Step Width Research Articles

To the problem of improving technical skills of ski racers

The article examines the ways of optimizing the educational process and improving the management of motor actions in sports training by using different activity conditions (modes, action tasks) and creating functional systems of the technology of progression of sports skills. It has been established that the regimes of alternating exercises with rest are a means of selective action on indicators of general and special work capacity, coordination structure of movements, reaction of the body’s service systems. The effect of alternating exercise regimes with rest "A" and "B" and action tasks "faster thrust", "wider step" on the change of individual indicators of technique, movements, speed, speed endurance of ski racers when overcoming climbs was established. The practical significance of the obtained data is that they allow building models of directed and previously known action not only for the change of the integral indicator of special performance, but also for the parameters of the coordination structure of movements, as well as to determine the athlete's behavior program depending on the topography of the competition. Research results make it possible to create models of lessons that selectively affect various systems of the athletes' body and contribute to more accurate management of the development of special working capacity, the formation of technical skills. The application of these models in the general structure of the development of special capacity for work creates an opportunity to comprehensively influence a person as a complex organized, self-regulating system. Practical use of research results optimizes the process of managing sports training over a longer period of time.

Effects of individually optimized rocker midsoles and self-adjusting insoles on dynamic stability in persons with diabetes mellitus and neuropathy

BackgroundPersons with diabetic peripheral neuropathy (DPN) may face challenges such as balance issues due to reduced somatosensory feedback and an increased risk of developing diabetic foot ulcers (DFUs) due to increased plantar pressure. Pressure reducing footwear is thought to further impair balance. We introduced 3D-printed rocker midsoles and self-adjusting insoles that are able to reduce elevated plantar pressure values and aimed to prevent balance deterioration. However, their effect on the balance during walking (dynamic stability) is not analyzed yet. Research questionIs dynamic stability of persons with DPN impaired compared to healthy individuals and what is the effect of the 3D-printed rocker midsoles and self-adjusting insoles on the dynamic stability in this population? MethodsDynamic stability, specifically the margins of stability (MOS) in the anterior-posterior (AP) and medio-lateral (ML) direction, was measured in ten healthy and nineteen persons with DPN. Independent-samples t-test was applied to analyze the difference in the MOS between groups. One-way repeated measures analyses of variance (ANOVA) was conducted to test the difference between the therapeutic footwear combinations within the DPN group. ResultsThere is no significant difference between the healthy and DPN group in MOS-AP. MOS-ML is significantly larger in DPN compared to the healthy participants. Using the self-adjusting insole shows a significantly lower (negative) MOS-AP compared to when using a rocker shoe within the DPN group. SignificanceThis study provides valuable information on whether DPN and our therapeutic footwear have a negative effect on the dynamic stability. DPN does not have a negative effect on dynamic stability in the AP direction. For the ML direction, DPN seems to cause larger MOS-ML by likely using a compensation strategy (e.g., wider steps) while our experimental footwear does not further impair the MOS-ML.

Effects of sedentary behaviour and long-term regular Tai Chi exercise on dynamic stability control during gait initiation in older women.

Background: Sedentary behaviour has been associated with an increased risk of falls among older adults. Although gait initiation (GI) is a promising tool used to assess fall risk, it has yet to be quantitatively evaluated for dynamic stability in sedentary populations. Tai Chi exercise is believed to be effective in preventing falls in older adults, but its effect on GI stability has not been quantified. This study aims to compare the stability of GI in sedentary older individuals versus those who are long-term Tai Chi exercisers by using a quantitative approach. Methods: This study included 17 sedentary older women without exercise habits (age: 65.59 ± 3.66 years, average daily sitting time: 8.735 ± 1.847h/day) and 19 older women who regularly engage in Tai Chi exercise (age: 65.58 ± 3.63 years, years of exercise: 9.84 ± 3.48 years). Every participant underwent five trials of self-paced GI walking tests. Eight cameras and four force plates were used to obtain kinematic and kinetic parameters. The trajectory of the centre of mass (CoM) and the position of the foot placement were recorded. The anterior-posterior (A-P) and medio-lateral (M-L) dynamic stability at the onset and end moments of the single-legged support was calculated using CoM and gait spatiotemporal parameters. The stepping dynamic stability and foot placement positions of both groups were compared. Results: The Tai Chi group had greater stability in the M-L directions at the swing leg's toe-off moment and in the M-L and A-P directions at the heel-strike moment, as well as significantly larger step length, step width and step speed during locomotion than sedentary older women. However, the stability in the A-P directions at the swing leg's toe-off moment and the foot inclination angle was not statistically different between the two groups. Conclusion: Long-term regular Tai Chi exercise can enhance the dynamic stability of GI in older women, and effectively improve their foot placement strategy during GI. The findings further confirm the negative effect of sedentary on the stability control of older women and the positive role of Tai Chi in enhancing their gait stability and reducing the risk of falls.

Attention and sensory integration for gait in young adults with autism spectrum disorder

IntroductionAltered sensorimotor function is a common feature of autism spectrum disorder (ASD). As a result, spatiotemporal walking patterns are typically affected. Attentional processes relevant for locomotion may be altered in people with ASD. This study assessed the extent to which gait alterations observed under sensory challenging conditions are due to reduced attention-related processes in young adults with ASD. MethodsTwenty-one adults with ASD and 21 age- and sex-matched neurotypical participants walked at a self-selected pace on a 10-m walkway under 12 sensory/attention conditions: hard or carpet flooring; well-lit or dim lighting; no attention task, an auditory choice-reaction time information-processing task, or a simple reaction time information-processing task. Gait data were collected with a 12-marker motion capture set and a trunk accelerometer. Spatiotemporal characteristics of gait were derived and compared between the two groups across gait conditions. ResultsFloor/light conditions impacted gait speed, average step length, average stance time, average step width, and step width variability similarly in both groups (p<0.05). The information processing tasks impacted average step length, gait speed, and step length variability (p<0.05). Group differences were found in step length metrics: the ASD group had decreased average step length during the simple reaction time information-processing task and neurotypical participants did not (p=0.039); the ASD group had increased variability on carpet compared to hard floor and the neurotypical group had no change in variability due to floor (p=0.015). SignificanceThese results suggest that attentional set-shifting and somatosensory inputs may play an important role in ASD-related gait alterations. Step length metrics appear to be sensitive to group differences between ASD and neurotypical adults during sensory challenging conditions.

The Effect of a Cognitive Dual Task on Gait Parameters among Healthy Young Adults with Good and Poor Sleep Quality: A Cross-Sectional Analysis.

Background: Sleep quality is known to affect automatic and executive brain functions such as gait control and cognitive processing. This study aimed to investigate the effect of dual tasks on gait spatiotemporal parameters among young adults with good and poor sleep quality. Methods: In total, 65 young adults with a mean age of 21.1 ± 2.5 were assessed for gait analysis during single-task and dual-task conditions. The participants' sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and gait was assessed using the BTS Gaitlab System. The participants were asked to walk at natural speed as a single-task condition, followed by walking while performing a cognitive task as a dual-task condition. The parameters assessed included the gait velocity (m/s), cadence (steps/min), step width (m), and stride length (m). The dual-task cost (DTC) on each gait parameter was calculated. The Mann-Whitney U test was used to compare the differences in the DTC on gait variables between the good and poor sleep quality groups and the Spearman correlation test was used to assess the correlation between total PSQI scores and the DTC. Results: At a significance level of p < 0.05, a significant difference in cadence between the two sleep quality groups was observed, in addition to a positive correlation between sleep quality and the DTC effect on gait mean velocity, cadence, and stride length. Our findings also revealed a greater DTC in participants with poorer sleep quality. Conclusions: These findings contribute to our perception of the significance of sleep quality in gait performance while multitasking in younger populations.

Movement strategies during obstacle crossing in people with Parkinson disease: A systematic review with meta-analysis.

Navigating obstacles involves adjusting walking patterns, particularly when stepping over them. This task may be particularly challenging for people with Parkinson disease (PD) for several reasons.This review aims to compare the spatiotemporal gait parameters of people with and without PD while stepping over obstacles. A systematic literature search was conducted in six databases (PubMed, Scopus, Web of Science, EBSCO, Embase, and SciELO) from inception to September 2023. Studies were selected that evaluated gait parameters of people with and without PD while walking over obstacles. Two independent researchers evaluated the eligibility and extracted gait parameters during obstacle crossing. The risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist. Heterogeneity was assessed using I2-tests. Random effects models were determined for effect sizes as standardized mean differences (SMD). Twenty-five studies were included in the review and 17 in the meta-analysis. Most of the studies (58%) showed a low risk of bias. People with PD exhibit a shorter step when landing after crossing an obstacle (SMD = -0.50 [-0.69 to -0.31]). Compared to people without PD, people with PD also widen their support base (SMD = 0.27 [0.07-0.47]) and reduce gait velocity (SMD = -0.60 [-0.80 to -0.39]) when crossing the obstacle. People with PD adopt a more conservative motor behavior during obstacle crossing than those without PD, with a shorter step length when landing after crossing an obstacle, greater step width and lower crossing speed.

Alterations in Step Width and Reaction Times in Walking Subjects Exposed to Mediolateral Foot-Transmitted Vibration

This study explores how low-frequency foot-transmitted vibration (FTV) affects both gait parameters and cognitive performance. Twenty healthy male participants experienced harmonic mediolateral FTV (1.25 Hz, 1 m/s2) while either standing or walking on a treadmill. We assessed participants’ reaction times to visual stimuli using a psychomotor vigilance task (PVT) test under five conditions, including (i) baseline (standing still without vibration), (ii) vibration (standing still with vibration), (iii) walking (walking without vibration), (iv) walking with vibration, and (v) post-test (standing still without vibration after the tests). Additionally, the step width (SW) was measured with a camera system in conditions (iii) and (iv), i.e., when participants were walking with and without vibration and during PVT execution. The results showed that the average vigilance decreased, and the step width increased while walking and/or with vibration exposure. These findings suggest a potential connection between decreased vigilance, increased step width, and the need for enhanced stability, focusing on balance maintenance and a wider base of support. Implications for future standard revisions are presented and discussed.

Ubiquitous Gait Analysis through Footstep-Induced Floor Vibrations.

Quantitative analysis of human gait is critical for the early discovery, progressive tracking, and rehabilitation of neurological and musculoskeletal disorders, such as Parkinson's disease, stroke, and cerebral palsy. Gait analysis typically involves estimating gait characteristics, such as spatiotemporal gait parameters and gait health indicators (e.g., step time, length, symmetry, and balance). Traditional methods of gait analysis involve the use of cameras, wearables, and force plates but are limited in operational requirements when applied in daily life, such as direct line-of-sight, carrying devices, and dense deployment. This paper introduces a novel approach for gait analysis by passively sensing floor vibrations generated by human footsteps using vibration sensors mounted on the floor surface. Our approach is low-cost, non-intrusive, and perceived as privacy-friendly, making it suitable for continuous gait health monitoring in daily life. Our algorithm estimates various gait parameters that are used as standard metrics in medical practices, including temporal parameters (step time, stride time, stance time, swing time, double-support time, and single-support time), spatial parameters (step length, width, angle, and stride length), and extracts gait health indicators (cadence/walking speed, left-right symmetry, gait balance, and initial contact types). The main challenge we addressed in this paper is the effect of different floor types on the resultant vibrations. We develop floor-adaptive algorithms to extract features that are generalizable to various practical settings, including homes, hospitals, and eldercare facilities. We evaluate our approach through real-world walking experiments with 20 adults with 12,231 labeled gait cycles across concrete and wooden floors. Our results show 90.5% (RMSE 0.08s), 71.3% (RMSE 0.38m), and 92.3% (RMSPE 7.7%) accuracy in estimating temporal, spatial parameters, and gait health indicators, respectively.

Optimization of stepped revetment configuration on minimizing wave run-up and overtopping

A stepped revetment has proven to be able to attenuate wave run-up height and wave overtopping discharge more effectively than a dike or a smooth-slope revetment does. However, the investigation into the optimal design of a stepped revetment, tailored to different wave and coastal conditions, is notably lacking. This paper introduces a computational model developed from the non-linear shallow water equations and the Genetic Algorithm. The aim is to optimize the width of a stepped revetment's step and crest, considering wave run-up and overtopping as key parameters. Multiple benchmark tests were conducted to validate the model's accuracy in estimating wave run-up and overtopping for specific setups. The results demonstrate a strong correlation between the numerical findings and experimental data. The Genetic Algorithm was then employed to predict the optimal step width for minimizing wave run-up height and determining the optimal step and crest widths to reduce wave overtopping discharge to an acceptable level. The findings reveal that for a gently sloping stepped revetment, the optimal step widths, based on wave run-up, remain relatively consistent across different wave heights. In contrast, when optimizing for wave overtopping, the optimal step width tends to fluctuate in most cases, although it shows some consistency in certain scenarios.

Mild exercise expedites joint clearance and slows joint degradation in a joint instability model of osteoarthritis in male rats

ObjectiveExercise remains a hallmark treatment for post-traumatic osteoarthritis (PTOA) and may maintain joint homeostasis in part by clearing inflammatory cytokines, cells, and particles. It remains largely unknown whether exercise-induced joint clearance can provide therapeutic relief of PTOA. In this study, we hypothesized that exercise could slow progression of preclinical PTOA in part by enhancing knee joint clearance. DesignSurgical medial meniscal transection was used to induce PTOA in 3-month-old male Lewis rats. A sham surgery was used as a control. Mild treadmill walking was introduced 3 weeks post-surgery and maintained to 6 weeks post-surgery. Gait and isometric muscle torque were measured at the study endpoint. Near-infrared imaging tracked how exercise altered lymphatic and venous knee joint clearance during discrete time points of PTOA progression. ResultsExercise mitigated joint degradation associated with PTOA by preserving glycosaminoglycan content and reducing osteophyte volume (effect size (95% CI); 1.74 (0.71-2.26). PTOA increased hind step widths (0.57 (0.18-0.95) cm), but exercise corrected this gait dysfunction (0.54 (0.16-0.93) cm), potentially indicating pain relief. Venous, but not lymphatic, clearance was quicker 1-, 3-, and 6-weeks post-surgery compared to baseline. The mild treadmill walking protocol expedited lymphatic clearance rate in moderate PTOA (3.39 (0.20-6.59) hrs), suggesting exercise may play a critical role in restoring joint homeostasis. ConclusionsWe conclude that mild exercise has the potential to slow disease progression in part by expediting joint clearance in moderate PTOA.

Walking (and talking) the plank: dual-task performance costs in a virtual balance-threatening environment.

We evaluated the effects of engaging in extemporaneous speech in healthy young adults while they walked in a virtual environment meant to elicit low or high levels of mobility-related anxiety. We expected that mobility-related anxiety imposed by a simulated balance threat (i.e., virtual elevation) would impair walking behavior and lead to greater dual-task costs. Altogether, 15 adults (age = 25.6 ± 4.7 yrs, 7 women) walked at their self-selected speed within a VR environment that simulated a low (ground) and high elevation (15m) setting while speaking extemporaneously (dual-task) or not speaking (single-task). Likert-scale ratings of cognitive and somatic anxiety, confidence, and mental effort were evaluated and gait speed, step length, and step width, as well as the variability of each, was calculated for every trial. Silent speech pauses (> 150ms) were determined from audio recordings to infer the cognitive costs of extemporaneous speech planning at low and high virtual elevation. Results indicated thatthe presence of a balance threat and the inclusion of a concurrent speech task both perturbed gait kinematics, but the virtual height illusion led to increased anxiety and mental effort and a decrease in confidence. The extemporaneous speech pauses were longer on average when walking, but no effects of virtual elevation were reported. Trends toward interaction effects arose in self-reported responses, with participants reporting more comfort walking at virtual heights if they engaged in extemporaneous speech. Walking at virtual elevation and while talking mayhave independent and significant effects on gait; both effects were robust and did not support an interaction when combined (i.e., walking and talking at virtual heights). The nature of extemporaneous speech may have distracted participants from the detrimental effects of walking in anxiety-inducing settings.

Adhesive elastic tape modifies forefoot motion in young women with flatfoot

PurposeFlatfoot has been associated with an increased risk of lower limb injuries. Therefore, it is crucial to assess the efficacy of therapeutic interventions focused on foot realignment. This study aimed to investigate the effect of elastic tape on the motion of the forefoot, midfoot, and hindfoot in young women.MethodsBlinded self-controlled clinical trial. The study included 10 women aged 18–30 years with flat feet, as classified by the Foot Posture Index, to improve the homogeneity of the participants. Three-dimensional gait analysis of the 10 women with flatfoot was done without and with elastic tape. It was applied on the side with the greater magnitude of flatfoot (experimental) and the opposite side was used as the control. The Oxford Foot Model was used to assess the foot kinematics. Independent and paired t-tests, and the Wilcoxon and Mann–Whitney tests were used for comparisons.ResultsElastic tape did not alter the spatial-temporal gait parameters, such as cadence, gait speed, double-support duration, single-support duration, step length, and step width. The tape did modify the frontal forefoot motion during initial contact, toe-off, and maximum pronation. These differences were confirmed through both intragroup and intergroup comparisons. The tape did alter the arch height and deformation, but these differences were observed only in intragroup comparisons. The tape did not affect the frontal hindfoot motion during the initial contact, toe-off, and maximum pronation.ConclusionsThe application of the elastic tape altered the frontal forefoot motion in female participants in the short-term. It resulted in improved forefoot supination during the initial contact, toe-off and maximum pronation. The tape did not influence the arch height or the frontal hindfoot motion.

Assessment of Alterations in Gait Parameters of Chronic Total Knee Arthroplasty – An Observational Study

Purpose of the Study: This research investigates postoperative gait alterations in individuals aged 50 and above who underwent total knee arthroplasty (TKA) at least one year ago. The study aims to fill existing gaps in literature by comprehensively assessing various gait parameters and understanding the persistent changes in mobility following TKA. Materials and Methods: Conducted as an observational study, 30 TKA subjects were assessed using Kinovea software for gait parameters, including cadence, speed, step length, step width, stride length, and knee flexion angle. Statistical analysis with MS Excel compared obtained values with established norms. Results: Significant gait parameter alterations were observed in post-TKA subjects. These changes include decreased cadence, walking speed, step length, and stride length, along with variations in knee flexion angle. Approximately 36.67% of participants exhibited alterations in these parameters, highlighting the need for further understanding of mobility challenges post-TKA. Conclusion: This study contributes vital insights into the persistent impact of TKA on gait parameters, emphasizing the complexity of postoperative mobility changes. The observed alterations highlight the importance of tailored rehabilitation programs to enhance functional independence and address long-term gait concerns in this patient population.

Magnetoelectric transport properties in topological nodal-line semimetals

We study the impact of the size effect and the varying perpendicular magnetic field B on the transport properties of topological nodal-line semimetals (TNLSMs) by using the Landauer–Büttiker formula combined with the nonequilibrium Green’s function. We theoretically calculate the band structure, conductance G and local density of states (LDOS) of TNLSMs nanowire. The results show that both the size effect and the application of varying magnetic field play a crucial role in the electron transport of TNLSMs. We find that both the step height and width of the conductance plateau in TNLSMs are closely related to the size effect of the system. For the system with a large TNLSMs, the low energy states are dominated by flat bands, leading to a series of quantized conductance plateaus. Furthermore, it has been observed that the presence of a magnetic field leads to the formation of the Landau levels in the TNLSMs, which exhibit sensitivity to the direction of the applied magnetic field. A perpendicular magnetic field parallel to the transport direction forms a linearly dispersed Landau level in the TNLSMs system, which leads to an increase in its conductance G and LDOS. At the same time, when the magnetic field perpendicular to the transport direction is applied, a series of the Landau levels with the flat bands are formed near the Fermi energy level EF of the system, resulting in a significant decrease of its conductance G and a rapid decay of LDOS. These unique physical properties of the TNLSMs nanowire offer a wide range of the applications in magnetoelectric transport.

Adaptive gait responses to varying weight-bearing conditions: Inferences from gait dynamics and H-reflex magnitude.

This study investigates the effects of varying loading conditions on excitability in neural pathways and gait dynamics. We focussed on evaluating the magnitude of the Hoffman reflex (H-reflex), a neurophysiological measure representing the capability to activate motor neurons and the timing and placement of the foot during walking. We hypothesized that weight manipulation would alter H-reflex magnitude, footfall and lower body kinematics. Twenty healthy participants were recruited and subjected to various weight-loading conditions. The H-reflex, evoked by stimulating the tibial nerve, was assessed from the dominant leg during walking. Gait was evaluated under five conditions: body weight, 20% and 40% additional body weight, and 20% and 40% reduced body weight (via a harness). Participants walked barefoot on a treadmill under each condition, and the timing of electrical stimulation was set during the stance phase shortly after the heel strike. Results show that different weight-loading conditions significantly impact the timing and placement of the foot and gait stability. Weight reduction led to a 25% decrease in double limb support time and an 11% narrowing of step width, while weight addition resulted in an increase of 9% in step width compared to body weight condition. Furthermore, swing time variability was higher for both the extreme weight conditions, while the H-reflex reduced to about 45% between the extreme conditions. Finally, the H-reflex showed significant main effects on variability of both stance and swing phases, indicating that muscle-motor excitability might serve as feedback for enhanced regulation of gait dynamics under challenging conditions.

Spatiotemporal variability after stroke reflects more than just slow walking velocity

BackgroundIncreased spatiotemporal gait variability is considered a clinical biomarker of ageing and pathology, and a predictor of future falls. Nevertheless, it is unclear whether the increased spatiotemporal variability observed in persons with stroke is directly related to the pathology or simply reflects their choice of walking velocity. Research questionDoes increased spatiotemporal gait variability directly relate to motor coordination deficits after stroke? MethodsForty persons with stroke participated in this cross-sectional study. Participants performed the lower-extremity motor coordination test (LEMOCOT) on an electronic mat equipped with force sensors. Then, participants walked for 120 s on a computerized treadmill at their comfortable walking velocity. For the LEMOCOT we used the traditional score of in-target touch count and computed the absolute and variable error around the targets. For gait variability, we extracted the standard deviation of step time, step length, step velocity, and step width. Using linear modeling, we tested the correlations of gait variability with the outcome measures from the LEMOCOT, after controlling for walking velocity. ResultsThe variability in step time, step length and step width correlated with walking velocity, while the variability in step velocity did not. After controlling for walking velocity, we observed that the LEMOCOT score correlated with the variance in step time, and the variable error in the LEMOCOT correlated with the variance in step length, in step width, and in step velocity. No significant correlation with any of the velocity-controlled step parameters was found for the absolute error in the LEMOCOT. SignificanceDecreased performance in the LEMOCOT was associated with increased spatiotemporal variability in persons with stroke, regardless of their walking velocity. Our results demonstrate the connection between lower-extremity coordination impairments and deficits in gait function.

The influence of prosthetic suspension on gait and cortical modulations is persons with a transfemoral amputation: socket-suspended versus bone-anchored prosthesis

BackgroundPersons with a transfemoral amputation (TFA) often experience difficulties in daily-life ambulation, including an asymmetrical and less stable gait pattern and a greater cognitive demand of walking. However, it remains unclear whether this is effected by the prosthetic suspension, as eliminating the non-rigid prosthetic connection may influence stability and cortical activity during walking. Spatiotemporal and stability-related gait parameters, as well as cortical activity during walking, were evaluated between highly active individuals (MFC-level K3-4) with a TFA and able-bodied (AB) persons, and between persons with a bone-anchored prosthesis (BAP) and those with a socket-suspended prosthesis (SSP).Methods18 AB persons and 20 persons with a unilateral TFA (10 BAP-users, 10 SSP-users) walked on a treadmill at their preferred speed. Spatiotemporal and margin of stability parameters were extracted from three-dimensional movement recordings. In addition, 126-channel electroencephalogram (EEG) was recorded. Brain-related activity from several cortical areas was isolated using independent component analysis. Source-level data were divided into gait cycles and subjected to time–frequency analysis to determine gait-cycle dependent modulations of cortical activity.ResultsPersons with TFA walked with smaller and wider steps and with greater variability in mediolateral foot placement than AB subjects; no significant differences were found between BAP- and SSP-users. The EEG analysis yielded four cortical clusters in frontal, central (both hemispheres), and parietal areas. No statistically significant between-group differences were found in the mean power over the entire gait cycle. The event-related spectral perturbation maps revealed differences in power modulations (theta, alpha, and beta bands) between TFA and AB groups, and between BAP- and SSP-users, with largest differences observed around heel strike of either leg.ConclusionsThe anticipated differences in gait parameters in persons with TFA were confirmed, however no significant effect of the fixed suspension of a BAP was found. The preliminary EEG findings may indicate more active monitoring and control of stability in persons with TFA, which appeared to be timed differently in SSP than in BAP-users. Future studies may focus on walking tasks that challenge stability to further investigate differences related to prosthetic suspension.

Individuals with knee osteoarthritis show few limitations in balance recovery responses after moderate gait perturbations

BackgroundKnee osteoarthritis causes structural joint damage. The resultant symptoms can impair the ability to recover from unexpected gait perturbations. This study compared balance recovery responses to moderate gait perturbations between individuals with knee osteoarthritis and healthy individuals. MethodsKinematic data of 35 individuals with end-stage knee osteoarthritis, and 32 healthy individuals in the same age range were obtained during perturbed walking on a treadmill at 1.0 m/s. Participants received anteroposterior (acceleration or deceleration) or mediolateral perturbations during the stance phase. Changes from baseline in margin of stability, step length, step time, and step width during the first two steps after perturbation were compared between groups using a linear regression model. Extrapolated center of mass excursion was descriptively analyzed. FindingsAfter all perturbation modes, extrapolated center of mass trajectories overlapped between individuals with knee osteoarthritis and healthy individuals. Participants predominantly responded to mediolateral perturbations by adjusting their step width, and to anteroposterior perturbations by adjusting step length and step time. None of the perturbation modes yielded between-group differences in changes in margin of stability and step width during the first two steps after perturbation. Small between-group differences were observed for step length (i.e. 2 cm) of the second step after mediolateral and anteroposterior perturbations, and for step time (i.e. 0.01–0.02 s) of first step after mediolateral perturbations and the second step after outward and belt acceleration perturbations. InterpretationDespite considerable pain and damage to the knee joint, individuals with knee osteoarthritis showed comparable balance recovery responses after moderate gait perturbations to healthy participants.

Gait Biomechanical Parameters Related to Falls in the Elderly: A Systematic Review

According to the World Health Organization, one-third of elderly people aged 65 or over fall annually, and this number increases after 70. Several gait biomechanical parameters were associated with a history of falls. This study aimed to conduct a systematic review to identify and describe the gait biomechanical parameters related to falls in the elderly. MEDLINE Complete, Cochrane, Web of Science, and CINAHL Complete were searched for articles on 22 November 2023, using the following search sentence: (gait) AND (fall*) AND ((elder*) OR (old*) OR (senior*)) AND ((kinematic*) OR (kinetic*) OR (biomechanic*) OR (electromyogram*) OR (emg) OR (motion analysis*) OR (plantar pressure)). This search identified 13,988 studies. From these, 96 were selected. Gait speed, stride/step length, and double support phase are gait biomechanical parameters that differentiate fallers from non-fallers. Fallers also tended to exhibit higher variability in gait biomechanical parameters, namely the minimum foot/toe clearance variability. Although the studies were scarce, differences between fallers and non-fallers were found regarding lower limb muscular activity and joint biomechanics. Due to the scarce literature and contradictory results among studies, it is complex to draw clear conclusions for parameters related to postural stability. Minimum foot/toe clearance, step width, and knee kinematics did not differentiate fallers from non-fallers.

The Effect of 8 Weeks of Otago Exercise on the Selected Walking Factors in Patients With Parkinson Disease

Background and Aims Physical activities play a preventive role in Parkinson disease by maintaining the physical fitness and health of the patients. This study aimed to investigate the effect of 8 weeks of Otago exercise on selected walking factors in patients with Parkinson disease. Methods This quasi-experimental study was performed on the experimental and control groups with a pretest-posttest design. The statistical population of the present study comprised all patients with Parkinson disease (with at least stage three on the Hoehn and Yahr intensity scale) referred to the neurologist offices with an age range of 55-75 years. The subjects were randomly divided into groups of Otago exercises (n=16, with Mean±SD age: 63.0±6.4 years, Mean±SD weight: 65.7±5.2 kg, and mean height 1.74±0.07 m) and control (n=16; with Mean±SD age: 63.4±5.7 years, Mean±SD weight: 64.1±5.9 kg, and Mean±SD height: 1.72±0.09 m). Eight weeks of Otago exercise was performed three times a week for 60 minutes at each session. A motion analysis system consisting of 8 cameras and 2 force plates was used to record selected walking factors, including step length, step width, and knee joint extension changes. The paired t test was used to compare each group in the pretest and posttest, and analysis of covariance (ANCOVA) was used to compare between groups. Results The results showed significant differences in the step length, step width, and knee extension changes in patients with Parkinson disease between the experimental and control groups (P&lt;0.001). Also, the results showed that patients with Parkinson disease had longer step length, shorter step width, and greater knee extension in both legs after Otago exercise. Conclusion Otago exercises can be used as one of the easy and low-cost methods in improving the walking components of patients with Parkinson disease.