Double Support Phase Research Articles

ATUAÇÃO DA FISIOTERAPIA NA MELHORA DAMARCHA DOS PACIENTES ACOMETIDOS COM PARKINSON: REVISÃO DE LITERATURA

INTRODUCTION: Parkinson's disease is a neurodegenerative disorder of idiopathic etiology, characterized by a progressive decline in dopamine levels in the substantia nigra of the midbrain. The motor circuitry occurs in the basal ganglia, which are responsible for voluntary movements.The kinematic analysis of gait of these individuals shows an asymmetry in gait pattern, where difficulties in regulating the temporal-spatial are observed, altering step and stride length, increasing the time spent in double support phase. Physical therapy assists in treating motor dysfunctions in these patients, reducing the impact that the disease causes on their lives, providing an improvement in their overall physical condition. OBJECTIVE: To analyze scientific studies that observe improvements in the gait cycle of individuals affected by Parkinson's disease, using physiotherapeutic approaches as treatment. METHODOLOGY: A literature review, using the database Scientific Electronic Library Online (SciELO), CAPES Journal, ScienceDirect (Elservier), and collections in the Cruzeiro do Sul University library. RESULTS: Scientific articles were found in Portuguese, English, and Spanish, from the period between 2004 and 2024, which covered physiotherapeutic treatments related to gait and were available for free in the previously mentioned databases. EXCLUSION CRITERIA: Scientific articles older than 20 years, physiotherapeutic treatments that do not include gait, paid databases, or those not included in the databases cited above. CONCLUSION: The main objective of the present study was to identify physiotherapeutic treatments that improve gait in patients affected by Parkinson's disease, ainming to reduce the impacts caused by progressive neurodegeneration of the neuromotor system. Despite of the studies presented in this work, further research is needed with a specific focus on the treatment of gait in individuals with the disease.

Gait coordination control of bipedal modular reconfigurable robot based on adaptive neural network

This paper proposed an adaptive neural network (NN) control method to track the desired trajectory of a bipedal modular reconfigurable robot (MRR), which can solve the gait coordination problem of bipedal MRR. The leg dynamic model and the body dynamic model of bipedal MRR are established based on the Newton–Euler iterative method, and the global dynamic model is subsequently established. Aiming at the gait coordination problem between double support phase (DSP) and single support phase (SSP), the desired trajectory is generated based on the zero-moment point (ZMP) method. The adaptive NN controller is designed to track the generated desired trajectory, which also compensates interconnected dynamic coupling (IDC) effects of the bipedal MRR. The stability of bipedal MRR system is proved by Lyapunov theory. In the end, the effectiveness of the control method is verified by comparative simulation. The simulation results show that the proposed adaptive NN method reduces the position tracking error by [Formula: see text] and the control torque by [Formula: see text] compared with the existing control methods.

A novel rigid Foot-Ground contact model for Predicting ground reaction forces and center of pressure during normal gait

Ground reaction forces (GRFs) and center of pressure (COP) are essential for understanding human motion and evaluating biomechanical parameters, but measuring them with force plates is often limited in many scenarios. In this study, we propose a novel methodology for estimating GRFs and COP during normal gait based on a rigid foot–ground contact model, referred to as the COP phase transition continuity model (COP-PTCM). The GRFs and COP are calculated based on the Newton-Euler Equations during the single support phase (SSP). Considering the spatiotemporal continuity of the COP trajectory during normal gait, the COP data for the double support phase (DSP) is obtained by an improved logistic function fitted using the COP data from the SSP. GRFs during the DSP are optimized using the minimum energy hypothesis. The COP-PTCM method is used to estimate the GRFs and COP of ten participants during normal gait, and the results are compared with simultaneously measured force plate data, yielding the relative root mean square error (rRMSE) between measured and estimated GRFs in the anterior-posterior, vertical, and medial–lateral directions are 10.90 ± 2.09 %, 4.73 ± 1.44 %, and 15.17 ± 1.69 %, respectively. Additionally, the rRMSE between measured and estimated COP in the anterior-posterior direction is 11.23 ± 0.03 %. The above comparison validates the effectiveness and accuracy of the proposed method.

Early gait analysis after total knee arthroplasty based on artificial intelligence dynamic image recognition

To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty (TKA). From February 2023 to July 2023, 26 patients with unilateral knee osteoarthritis (KOA) were treated with TKA, including 4 males and 22 females, aged from 57 to 85 years old with an average of (67.58±6.49) years old;body mass index (BMI) ranged from 18.83 to 38.28 kg·m-2 with an average of (26.43±4.15) kg·m-2;14 patients on the left side, 12 patients on the right side;according to Kellgren-Lawrence(K-L) classification, 6 patients with grade Ⅲ and 20 patients with grade IV;the courses of disease ranged from 1 to 14 years with an average of (5.54±3.29) years. Images and videos of standing up and walking, walking side shot, squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation. The human posture estimation framework OpenPose were used to analyze stride frequency, step length, step length, step speed, active knee knee bending angle, stride length, double support phase time, as well as maximum hip flexion angle and maximum knee bending angle on squatting position. Western Ontario and McMaster Universities (WOMAC) arthritis index and Knee Society Score (KSS) were used to evaluate clinical efficacy of knee joint. All patients were followed up for 5 to 7 weeks with an average of (6.00±0.57) weeks. The total score of WOMAC decreased from (64.85±11.54) before operation to (45.81±7.91) at 6 weeks after operation (P<0.001). The total KSS was increased from (101.19±9.58) before operation to (125.50±10.32) at 6 weeks after operation (P<0.001). The gait speed, stride frequency and stride length of the affected side before operation were (0.32±0.10) m·s-1, (96.35±24.18) steps·min-1, (0.72±0.14) m, respectively;and increased to (0.48±0.11) m·s-1, (104.20±22.53) steps·min-1, (0.79±0.10) m at 6 weeks after operation (P<0.05). The lower limb support time and active knee bending angle decreased from (0.31±0.38) s and (125.21±11.64) ° before operation to (0.11±0.04) s and (120.01±13.35) ° at 6 weeks after operation (P<0.05). Eleven patients could able to complete squat before operation, 13 patients could able to complete at 6 weeks after operation, and 9 patients could able to complete both before operation and 6 weeks after operation. In 9 patients, the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation, and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation. Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of patients' gait. Knee pain of KOA was relieved and the function was improved, the supporting ability of the affected limb was improved after TKA, and the patient's stride frequency, stride length and stride speed were improved, and the overall movement rhythm of both lower limbs are more coordinated.

Gait Generation of a 10-DOF Humanoid Robot on Deformable Terrain Based on Spherical Inverted Pendulum Model

Abstract Gait generation of a humanoid robot on deformable terrain is a complex problem as the foot and terrain interaction and terrain deformation has to be included in the dynamics. In order to simplify the dynamics of walk on deformable terrain, we used a spherical inverted pendulum (SIP) to represent the single support phase, in which the effect of terrain deformation is represented by a spring and damper contact model. The impact model for leg transition is derived from angular momentum conservation. In order to minimize the energy loss due to impact, the double support phase is modeled as a suspended pendulum. Based on the motion of the SIP model, the hip and leg trajectories of a 10 DOF humanoid robot are generated. The joint angles of the humanoid are obtained from inverse kinematics. The motion of the center of mass is analyzed by inverse dynamics of a floating-base robot. The proposed gait generation method has been experimentally validated using a Kondo KHR-3HV humanoid robot on deformable terrain. The results show that the humanoid can effectively track the trajectories of the SIP model.

Rotation of the hammer and performance in hammer throwing.

The purpose of this study was to determine the effects of hammer rotation on performance in hammer throwing. The hammer's velocity increment at different stages, the duration of rotations at different phases, and the horizontal azimuth angle and rotation radius at critical instants were calculated and compared between the long and short trials for 26 female athletes in actual competitions. Compared to short trials, female throwers' long trials exhibited significantly larger release velocity (p < 0.001, ES = 1.42), greater velocity increment during the double support phase (p = 0.006, ES = 0.59), shorter duration during the single support phase (p ≤ 0.043, ES = 0.42-0.83), lower horizontal azimuth angle (p ≤ 0.027, ES = 0.46-0.57), and longer rotational radius at critical instants (p ≤ 0.021, ES = 0.48-0.73). During the process from the hammer head's low point to high point, athletes should focus on increasing the rotation radius of the hammer head and accelerating the right foot's landing speed during the single support phase. This approach aims to reduce the hammer's horizontal azimuth angle at the right foot touchdown, enhance the acceleration performance during the double support phase, and increase the release speed.

Comparison of knee biomechanical characteristics during gait between patients with knee osteoarthritis and healthy individuals

ObjectiveThis study aim to quantify the differences in knee biomechanics during gait between knee osteoarthritis (KOA) patients and healthy individuals. MethodsTwenty KOA patients (4 males and 16 females, 66.2 ± 7.7 years) and twenty controls (16 males and 4 females, 64.8 ± 5.4 years) were recruited for gait test using the motion capture system and force-platform system. The spatiotemporal parameters, knee kinematics and kinetics, and tibiofemoral contact force (TFCF) were calculated using an improved musculoskeletal model. ResultsKOA patients walked with reduced speed (48.6 %), stride length (32.9 %), stride height (33.0 %), time proportions of single-support phases (19.2 %), increased gait cycle time (31.0 %), time proportions of stance (8.5 %) and double-support phases (57.7–75.9 %). KOA patients had significant smaller peak flexion angle (29.1 %), flexion ROM (50.6 %) and peak flexion moment (90.2 %), greater peak adduction moment (KAM) (40.7 %), peak rotation moments (KRM) (50.0 %), KAM impulse (106.2 %) and KRM impulse (126.0 %). In proximodistal direction, greater medial TFCF impulse (238 %), total and medial first-peak TFCF (9.6 % and 15.2 %), and smaller lateral peak TFCF (33.3 %) and TFCF impulse (38.4 %) were found in KOA patients. Besides, significant differences were found in the total, medial and lateral peak TFCFs and TFCF impulses in mediolateral direction, and the medial and lateral TFCFs and TFCF impulses in anteroposterior direction. ConclusionsSignificant differences were found in the spatiotemporal parameters, knee kinematics and kinetics, and TFCF between the two groups. The results of this study have important implication for clinicians and rehabilitation physicians. These quantified biomechanical differences can provide data support for the personalized and quantified rehabilitation strategies, give suggestions for the exercises of KOA patients, help monitor disease, evaluate surgical treatment, and develop more effective preoperative planning and postoperative rehabilitation strategies.

Effect of robotic-assisted gait training program on spatiotemporal gait parameters for ambulatory children with cerebral palsy: A randomized control trial.

Gait training programs are commonly used to improve gait in children with cerebral palsy (CP). To compared the effects of robotic-gait assistant training (RAGT) and conventional body weight support treadmill training (CBWSTT) on gait parameters among ambulatory children with CP. The study is a randomized controlled trial of 36 children (17 in the RAGT group and 19 in the CBWSTT group) aged 5 to 14. Gait training involved 30-to 35-minute sessions three times per week over eight weeks. Mixed ANCOVA showed no main effect of time or group on all gait parameters (P > .05). Gross motor function measure dimensions D (GMFM D) and E (GMFM E) show main effects on step width. Stride length, step length, speed, swing phase, and double support phase interacted with GMFM D and E. There was a negative correlation between motor function level and the change from baseline. Children with lower motor function show a greater change from baseline. There were no significant differences between CBWSTT and RAGT for children with CP; however, with gait training interventions, the level of motor function should be considered.

The correlation of gait and muscle activation characteristics with locomotion dysfunction grade in elderly individuals.

To investigate the differences and regularity of gait and muscle activation characteristics parameters in the Locomotion Dysfunction Grade (LDG) scale assessment in elderly individuals, and analyse the correlation between objective parameters and scale grading. Thus, to propose a novel detection mode for elderly individuals, which combined the LDG scale with objective detection. It can not only provide quantitative data for intelligent evaluation and rehabilitation, but also provided more accurate reference for the classification of care levels in elderly care policies. Elderly individuals (n = 159) who underwent gait analysis and sEMG at the Chinese Rehabilitation Research Center from January 2019 to September 2023 were included. According to the LDG scale, the elderly individuals were divided into four groups, namely, the LDG4, LDG5, LDG6 groups and the healthy control group. Four indicators, namely, spatiotemporal, kinematic, dynamic gait parameters and muscle activation characteristics data, were collected. Changes in these characteristics of elderly individuals with lower extremity motor dysfunction were evaluated and analysed statistically. The spatiotemporal gait parameters were significantly lower in the LDG4, LDG5, LDG6 groups than in the healthy control group. The double support phase was positively correlated with the LDG, while the swing phase, step length and velocity were negatively correlated (P < 0.05). The movement angles of both hips, knees and ankles were significantly limited and negatively correlated with the LDG (P < 0.05). Compared with those in the healthy control group, the centre of pressure (COP) path length were greater, and the average COP velocity was significantly lower (P < 0.05) in the LDG4, LDG5, LDG6 groups. The regularity of muscle activation clearly changed. The root mean square of the gastrocnemius medialis was positively correlated with LDG (P < 0.05), while the tibialis anterior showed no regularity. As the LDG increased, the differences in spatiotemporal, kinematic and dynamic gait parameters between elderly individuals with motor dysfunction and the healthy individuals gradually increased. The muscle activation characteristics parameters showed an abnormal activation pattern. These parameters were correlated with the LDG, providing a more comprehensive and objective assessment of lower extremity motor function in elderly individuals, improve assessment accuracy, and help accurate rehabilitation.

Quantitative gait markers and the TUG time in chronic kidney disease

BackgroundPoor gait performance results in more fall incidents among people with chronic kidney disease (CKD). It is unknown what specific quantitative gait markers contribute to high fall risk in CKD and the size of their mediation effects. MethodsWe included 634 participants from the Taizhou Imaging Study who had complete gait and laboratory data. Quantitative gait assessment was conducted with a wearable insole-like device. Factor analysis was utilized to summarize fifteen highly correlated individual parameters into five independent gait domains. Prevalent CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min per 1.73 m2, which was calculated based on cystatin C. Regression models were created to examine the associations of prevalent CKD with quantitative gait markers and the TUG time. Mediation analysis was used to investigate whether poor quantitative gait parameters could be mediators and the proportion of their mediation effects. ResultsParticipants with prevalent CKD had a higher TUG time (odds ratio = 2.02, P = 0.025) and poor gait performance in the phase domain (standardized β = −0.391, FDR = 0.009), including less time in the swing phase (standardized β = −0.365, FDR = 0.027) and greater time in the double-support phase (standardized β = 0.367, FDR = 0.027). These abnormalities mediated the association of prevalent CKD with a high TUG time (for the swing phase: 31.6 %, Pmediation = 0.044; for the double-support phase: 29.6 %, Pmediation = 0.042; for the phase domain: 26.9 %, Pmediation = 0.048). ConclusionPoor phase-related gait abnormalities mediated the relationship between CKD and a high TUG time, suggesting that incorporating quantitative gait markers in specific domains may improve fall prevention programs for individuals with CKD.

Influence of regularly repeated asymmetric load on the locomotor system in sweep rowers

ABSTRACT This study aims to objectively evaluate the trunk posture of sweep rowers (bow-side rowers/stroke-side rowers) and compare the results with scull rowers and non-rowing controls. Sixty-four healthy individuals divided into four groups were assessed using a DIERS formetric III 4D device that is based on a method of moiré topography. There were seven parameters observed in an assessment of standing posture, and eight parameters were studied for an evaluation of posture during the gait cycle. In comparison with non-rowing controls and scull rowers, stroke-side rowers showed significantly greater rotational deviation of the trunk at the L3 vertebra level and a greater magnitude of scoliosis angle during walking throughout the single support phase on the left leg (p < 0.05). Stroke-side rowers also demonstrated greater magnitude of scoliosis angle than non-rowing controls in double support phase in the transition from the left to the right leg (p < 0.05). Moreover, as opposed to non-rowing controls, stroke-side rowers and scull rowers showed significantly greater values of coronal imbalance (p < 0.05). Bow-side rowers differed from non-rowing controls and scull rowers in a significantly greater magnitude of scoliosis angle throughout the single support phase on the left leg (p < 0.05). Trial registration number: clinicaltrials.gov (identifier: NCT05685563).

Association between Elastic Modulus of Foot Soft Tissues and Gait Characteristics in Young Individuals with Flatfoot.

Flatfoot is a common foot deformity, causing foot pain, osteoarthritis of the midfoot, and even knee and hip dysfunction. The elastic modulus of foot soft tissues and its association with gait biomechanics still remain unclear. For this study, we recruited 20 young individuals with flatfoot and 22 age-matched individuals with normal foot arches. The elastic modulus of foot soft tissues (posterior tibial tendon, flexor digitorum brevis, plantar fascia, heel fat pad) was obtained via ultrasound elastography. Gait data were acquired using an optical motion capture system. The association between elastic modulus and gait data was analyzed via correlation analysis. The elastic modulus of the plantar fascia (PF) in individuals with flatfoot was higher than that in individuals with normal foot arches. There was no significant difference in the elastic modulus of the posterior tibial tendon (PTT), the flexor digitorum brevis (FDB), or the heel fat pad (HFD), or the thickness of the PF, PTT, FDB, and HFD. Individuals with flatfoot showed greater motion of the hip and pelvis in the coronal plane, longer double-support phase time, and greater maximum hip adduction moment during walking. The elastic modulus of the PF in individuals with flatfoot was positively correlated with the maximum hip extension angle (r = 0.352, p = 0.033) and the maximum hip adduction moment (r = 0.429, p = 0.039). The plantar fascia is an important plantar structure in flatfoot. The alteration of the plantar fascia's elastic modulus is likely a significant contributing factor to gait abnormalities in people with flatfoot. More attention should be given to the plantar fascia in the young population with flatfoot.

Feedback equivalence of the chained mechanical system to the almost linear form and its use for the sustainable multi-step walking design

The main theoretical novelty of this paper is the state and feedback equivalence of the underactuated 4-degrees of freedom planar walking-like mechanical chain system with 3 actuators to its 8-dimensional almost linear form with 3 virtual inputs. Moreover, the only residual nonlinearity vanishes on the 4-dimensional linear subspace being forward invariant when 2 of 3 virtual inputs are set to be zero. Dynamics inside that subsystem is actually the chain of 4 integrators fed by the remaining single virtual input and it can be interpreted as a rich variety of synchronous movements of torsos and legs. In such a way, the seemingly abstract and purely theoretical result can be used to design the walking-like movement during the single-support phase. The impact effect during the impulsive-like double-support phase is then attenuated by further special trajectories tuning and finite-time stabilization technique which provides the sustainable multi-step walking design. Moreover, the target walking-like trajectory is attracted by nearby trajectories. This further justify the importance and usefulness of the mentioned state and feedback equivalence. Its viability is further demonstrated by the simulations of various scenarios of the walking-like movement and the respective torsos behaviors.

Cautious Gait during Navigational Tasks in People with Hemiparesis: An Observational Study.

Locomotor and balance disorders are major limitations for subjects with hemiparesis. The Timed Up and Go (TUG) test is a complex navigational task involving oriented walking and obstacle circumvention. We hypothesized that subjects with hemiparesis adopt a cautious gait during complex locomotor tasks. The primary aim was to compare spatio-temporal gait parameters, indicators of cautious gait, between the locomotor subtasks of the TUG (Go, Turn, Return) and a Straight-line walk in people with hemiparesis. Our secondary aim was to analyze the relationships between TUG performance and balance measures, compare spatio-temporal gait parameters between fallers and non-fallers, and identify the biomechanical determinants of TUG performance. Biomechanical parameters during the TUG and Straight-line walk were analyzed using a motion capture system. A repeated measures ANOVA and two stepwise ascending multiple regressions (with performance variables and biomechanical variables) were conducted. Gait speed, step length, and % single support phase (SSP) of the 29 participants were reduced during Turn compared to Go and Return and the Straight-line walk, and step width and % double support phase were increased. TUG performance was related to several balance measures. Turn performance (R2 = 63%) and Turn trajectory deviation followed by % SSP on the paretic side and the vertical center of mass velocity during Go (R2 = 71%) determined TUG performance time. People with hemiparesis adopt a cautious gait during complex navigation at the expense of performance.

Wearable biofeedback device to assess gait features and improve gait pattern in people with parkinson’s disease: a case series

IntroductionPeople with Parkinson’s Disease (PD) show abnormal gait patterns compromising their independence and quality of life. Among all gait alterations due to PD, reduced step length, increased cadence, and decreased ground-reaction force during the loading response and push-off phases are the most common. Wearable biofeedback technologies offer the possibility to provide correlated single or multi-modal stimuli associated with specific gait events or gait performance, hence promoting subjects’ awareness of their gait disturbances. Moreover, the portability and applicability in clinical and home settings for gait rehabilitation increase the efficiency in the management of PD. The Wearable Vibrotactile Bidirectional Interface (BI) is a biofeedback device designed to extract gait features in real-time and deliver a customized vibrotactile stimulus at the waist of PD subjects synchronously with specific gait phases. The aims of this study were to measure the effect of the BI on gait parameters usually compromised by the typical bradykinetic gait and to assess its usability and safety in clinical practice.MethodsIn this case series, seven subjects (age: 70.4 ± 8.1 years; H&Y: 2.7 ± 0.3) used the BI and performed a test on a 10-meter walkway (10mWT) and a two-minute walk test (2MWT) as pre-training (Pre-trn) and post-training (Post-trn) assessments. Gait tests were executed in random order with (Bf) and without (No-Bf) the activation of the biofeedback stimulus. All subjects performed three training sessions of 40 min to familiarize themselves with the BI during walking activities. A descriptive analysis of gait parameters (i.e., gait speed, step length, cadence, walking distance, double-support phase) was carried out. The 2-sided Wilcoxon sign-test was used to assess differences between Bf and No-Bf assessments (p < 0.05).ResultsAfter training subjects improved gait speed (Pre-trn_No-Bf: 0.72(0.59,0.72) m/sec; Post-trn_Bf: 0.95(0.69,0.98) m/sec; p = 0.043) and step length (Pre-trn_No-Bf: 0.87(0.81,0.96) meters; Post-trn_Bf: 1.05(0.96,1.14) meters; p = 0.023) using the biofeedback during the 10mWT. Similarly, subjects’ walking distance improved (Pre-trn_No-Bf: 97.5 (80.3,110.8) meters; Post-trn_Bf: 118.5(99.3,129.3) meters; p = 0.028) and the duration of the double-support phase decreased (Pre-trn_No-Bf: 29.7(26.8,31.7) %; Post-trn_Bf: 27.2(24.6,28.7) %; p = 0.018) during the 2MWT. An immediate effect of the BI was detected in cadence (Pre-trn_No-Bf: 108(103.8,116.7) step/min; Pre-trn_Bf: 101.4(96.3,111.4) step/min; p = 0.028) at Pre-trn, and in walking distance at Post-trn (Post-trn_No-Bf: 112.5(97.5,124.5) meters; Post-trn_Bf: 118.5(99.3,129.3) meters; p = 0.043). SUS scores were 77.5 in five subjects and 80.3 in two subjects. In terms of safety, all subjects completed the protocol without any adverse events.ConclusionThe BI seems to be usable and safe for PD users. Temporal gait parameters have been measured during clinical walking tests providing detailed outcomes. A short period of training with the BI suggests improvements in the gait patterns of people with PD. This research serves as preliminary support for future integration of the BI as an instrument for clinical assessment and rehabilitation in people with PD, both in hospital and remote environments.Trial registrationThe study protocol was registered (DGDMF.VI/P/I.5.i.m.2/2019/1297) and approved by the General Directorate of Medical Devices and Pharmaceutical Service of the Italian Ministry of Health and by the ethics committee of the Lombardy region (Milan, Italy).

Effects of Cognitive-Motor and Motor-Motor Dual Tasks on Gait Performance in Older Adults with Sarcopenia.

With the advent of global aging, the health of the older population has become a critical public health challenge. The purpose of this study was to investigate the effect of dual-tasking on gait performance in patients with sarcopenia. Thirty participants with sarcopenia (age: 70.73 ± 4.12 yr, MMSE score: 26.90 ± 3.00), including 14 males and 16 females, were selected according to the diagnostic criteria of the Asian Working Group on Sarcopenia. All participants were instructed to perform the gait test in three modes: single task (ST), cognitive-motor dual task (CMDT), and motor-motor dual task (MMDT). Statistical analyses were performed using one-way ANOVA to evaluate the effects of different task types on gait parameters of the participants. (1) Compared with ST walking, gait frequency, step length, and step speed decreased, and the gait cycle and double-support phase increased in patients with sarcopenia during dual-task walking (p < 0.05); (2) Compared with ST walking, gait variability indices such as stride frequency, stride length, and support period significantly increased in patients with sarcopenia during dual-task walking (p < 0.05). The increased difficulty in postural control caused by dual-task interference may reduce the safety of motor strategies in patients with sarcopenia and increase the risk of falls. Future studies should focus on the effects of exercise interventions on multitasking patterns in people with sarcopenia to promote balance function in these populations.

Machine learning approach to classifying declines of physical function and muscle strength associated with cognitive function in older women: gait characteristics based on three speeds.

The aging process is associated with a cognitive and physical declines that affects neuromotor control, memory, executive functions, and motor abilities. Previous studies have made efforts to find biomarkers, utilizing complex factors such as gait as indicators of cognitive and physical health in older adults. However, while gait involves various complex factors, such as attention and the integration of sensory input, cognitive-related motor planning and execution, and the musculoskeletal system, research on biomarkers that simultaneously considers multiple factors is scarce. This study aimed to extract gait features through stepwise regression, based on three speeds, and evaluate the accuracy of machine-learning (ML) models based on the selected features to solve classification problems caused by declines in cognitive function (Cog) and physical function (PF), and in Cog and muscle strength (MS). Cognitive assessments, five times sit-to-stand, and handgrip strength were performed to evaluate the Cog, PF, and MS of 198 women aged 65 years or older. For gait assessment, all participants walked along a 19-meter straight path at three speeds [preferred walking speed (PWS), slower walking speed (SWS), and faster walking speed (FWS)]. The extracted gait features based on the three speeds were selected using stepwise regression. The ML model accuracies were revealed as follows: 91.2% for the random forest model when using all gait features and 91.9% when using the three features (walking speed and coefficient of variation of the left double support phase at FWS and the right double support phase at SWS) selected for the Cog+PF+ and Cog-PF- classification. In addition, support vector machine showed a Cog+MS+ and Cog-MS- classification problem with 93.6% accuracy when using all gait features and two selected features (left step time at PWS and gait asymmetry at SWS). Our study provides insights into the gait characteristics of older women with decreased Cog, PF, and MS, based on the three walking speeds and ML analysis using selected gait features, and may help improve objective classification and evaluation according to declines in Cog, PF, and MS among older women.

A three-dimensional spring-loaded inverted pendulum walking model considering human movement speed and frequency

The spring-loaded inverted pendulum (SLIP) model is an effective model to capture the essential dynamics during human walking and/or running. However, most of the existing three-dimensional (3D) SLIP model does not explicitly account for human movement speed and frequency. To address this knowledge gap, this paper develops a new SLIP model, which includes a roller foot, massless spring, and concentrated mass. The governing equations-of-motion for the SLIP model during its double support phase are derived. It is noted that in the current formulation, the motion of the roller foot is prescribed; therefore, only the equations for the concentrated mass need to be solved. To yield model parameters leading to a periodic walking gait, a constrained optimization problem is formulated and solved using a gradient-based approach with a global search strategy. The optimization results show that when the attack angle ranges from 68° to 74°, the 3D SLIP model can yield a periodic walking gait with walking speeds varying from 0.5 to 2.0 m s−1. The predicted human walking data are also compared with published experimental data, showing reasonable accuracy.

Cyclogram-based evaluation of inter-limb gait symmetry in Prader-Willi Syndrome

BackgroundPrader-Willi syndrome (PWS) is characterized by a complex clinical condition, whose typical features lead to impaired motor and functional skills. To date, limited data is available as regards symmetry of gait in PWS. Research questionThe aim of this study was to characterize lower-limb asymmetry during gait in a group of Prader-Willi Syndrome (PWS) individuals by using the synchronized cyclograms and to compare it with those of two different control groups, a normal-weight group and an obese group. MethodsA total of 18 PWS, 30 normal weight (NW) and 28 obese individuals (OG) matched for age, sex and height were assessed via 3D gait analysis. Gait spatio-temporal parameters were computed together with angle-angle diagrams, characterized in terms of their geometric features (i.e. area, orientation, and trend symmetry index). ResultsIndividuals with PWS exhibit reduced speed, stride length and cadence and increased duration of both stance and double support phase than the other groups. OG was characterized by the same pattern when compared to NW. With respect to inter-limb symmetry, individuals with PWS exhibited significantly larger cyclogram areas at hip joint with respect to the other two groups (203.32 degrees2 vs. 130.73 degrees2 vs. 111.59 degrees2) and significantly higher orientation angle (4.17° vs. 2.11° vs. 1.22°) and Trend Symmetry (3.72 vs. 2.02 vs. 1.21) with respect to the other two groups at knee joint; no differences were found at ankle joint. Both individuals with PWS and those of OG exhibited reduced ROM at knee and ankle joints with respect with normal weight, but no statistically significant differences were observed between PWS and OG. SignificanceThe obtained results may provide novel and useful insights to understand better the impairments in motor control associated with this pathological state, supporting clinics in the identification of the best rehabilitation program for this rare pathological state, aimed to improve stability and motor control.

The Effect of Proprioceptive Insoles on Gait Kinematics in Healthy Participants

ABSTRACT Introduction Proprioceptive neuromuscular stimulating insoles (PNIs) enhance somatosensory information from the plantar region, thus modifying standing posture, balance, and ambulatory function. The present study investigated the short-term effects of customized PNIs on lower-limb kinematics during human locomotion. Materials and Methods Fifteen able-bodied volunteers were recruited and first examined with clinical evaluation of postural and feet behavior. Subjects performed 3-dimensional gait analysis (GA) while walking at self-selected speed in three different conditions: baseline, subjects barefoot; placebo, subjects wearing neutral insoles; and proprioceptive, subjects wearing PNIs. Spatiotemporal and kinematics data of the main lower-limb joints were acquired through a system of six photogrammetric infrared cameras acquiring at a sampling frequency of 100 Hz. Then, acquired parameters were compared in the three different conditions. Results We found a significant difference in the percentage of double-support phase (P = 0.022) and in ankle plantarflexion values during the toe-off phase of gait cycle (P = 0.022) between the three conditions. Post hoc analysis revealed that subjects wearing PNIs presented a significant reduction in percentage of double-support phase (P = 0.009) and reduced values of ankle plantarflexion during the toe-off phase of gait cycle (P = 0.02), compared with subjects in placebo condition. Conclusions Results suggest that proprioceptive insoles may induce modifications of gait biomechanics in able-bodied subjects, thus modulating movement strategies during human locomotion. Clinical Relevance These findings provide a basis for future investigation of the efficacy of these foot devices in a long-term period in able-bodied individuals and potentially in subjects with neurological impairment.