Motor Foot Research Articles

Effects of short foot exercises with ultrasound bio-feedback on motor learning and foot alignment: A double blinded randomized control trial.

Short foot exercises (SFE) take a long time to master and require a feedback tool to improve motor learning. This study aimed to investigate the effect of bio-feedback of talonavicular joint movements in learning SFE with ultrasound (US) imaging. This study included thirty-one healthy volunteers and was designed as a double-blind randomized control trial. Subjects were randomly assigned to one of two groups: the control group, which performed SFE under verbal instruction, and the US bio-feedback (USBF) group, which performed SFE with real-time bio-feedback of the talonavicular joint alignment. All subjects underwent two sessions of 5 minutes each, and SFE was performed as a self-exercise, between sessions, for one week. The difference in foot length and navicular height were assessed at baseline, after Session1, before Session2, and one week after Session2. These differences were compared between the two groups using the Mann-Whitney U test. In terms of navicular height change, the USBF group (7.5 ± 4.3 mm) was significantly higher than the control group (4.2 ± 3.3 mm) one week after session 2 (p= 0.04, effect size = 0.86). SFE with USBF is an effective intervention for performing SFE.

Unlocking the power of motor imagery: a comprehensive review on its application in alleviating foot pain.

Motor imagery is a cognitive process that involves mentally simulating movements without physical execution. It has been studied in the context of foot pain to understand the role of motor cortical reorganization and its impact on motor imagery abilities. However, further research is needed to establish consistent evidence regarding the relationship between motor imagery and foot pain. This review analyzed five relevant articles that investigated motor imagery in the context of foot pain. The studies involved participants with various conditions, including leg amputation, chronic leg pain, complex regional pain syndrome, and Achilles tendinopathy. Different methodologies were employed, including motor cortical mapping, foot laterality recognition tasks, EEG recordings, and treatment interventions incorporating motor imagery. The findings indicated that individuals with leg amputation exhibited functional reorganization in upper limb motor cortical maps, with a breakdown in the inhibitory relationship between foot and hand representations. Participants with chronic leg pain demonstrated slower and less accurate performance on foot laterality recognition tasks compared to healthy controls. Complex regional pain syndrome patients displayed distinct motor imagery strategies and responded differently to first-person and third-person perspectives. EEG studies revealed differences in brain activity during motor imagery tasks under pain-free and pain conditions. Treatment interventions incorporating motor imagery showed promising outcomes in improving functional outcomes and reducing pain levels. Motor imagery plays a significant role in foot pain conditions, although the evidence is still emerging. The findings suggest that motor imagery abilities may be affected by leg amputation, chronic pain, and complex regional pain syndrome. Further research is needed to establish standardized protocols for assessing motor imagery, identify specific patient populations that may benefit most from motor imagery interventions, and explore long-term effects. Integrating motor imagery into clinical practice has the potential to enhance rehabilitation approaches and improve outcomes in foot pain management.

Analytical Calculation Method of Motor Natural Frequencies Based on Equivalent Model of Three-Layer Cylindrical Shell

Accurate calculation of natural frequencies is significant for accurate prediction and suppression of motor vibration and noise. In order to reduce the errors caused by simplified structure in the analytical method, a new analytical calculation method (ACM) of the natural frequencies of the motor is proposed in this paper. The motor enclosure, stator yoke, stator teeth and windings are equivalent to a three-layer cylindrical shell model. The motor feet are equivalent to the axial ribs on the cylindrical shell. The artificial springs are used to simulate arbitrarily complex boundary conditions between the end covers and the enclosure. The combination of zig-zag theory and first-order shear deformation theory (FSDT) is used to calculate the natural frequencies of the equivalent model of the motor proposed in this paper. According to the zig-zag theory model, the respective displacement function and energy equation are established for each cylindrical shell. The different structural dimensions and material properties between the motor enclosure, stator core and windings are considered. The first-order shear deformation theory is adopted in the displacement model of each layer of cylindrical shell, which considers transverse shear deformation, rotational inertia and orthotropy of materials. Finally, the accuracy of the analytical calculation method proposed in this paper is verified by finite element simulation (FES) and hammering method modal test (HMMT).

Changes in Distributed Motor Network Connectivity Correlates With Functional Outcome After Surgical Resection of Brain Tumors

BACKGROUND: In patients with brain tumors around the motor cortices, deterioration of motor performance may be observed even if the integrity of the cortical output is maintained. Especially, resection of medial premotor area (PM) can cause postoperative deterioration called supplementary motor area syndrome. OBJECTIVE: To clarify the neuronal mechanisms underlying postsurgical deterioration with a case-control study. METHODS: Twelve patients with brain tumors underwent preoperative and postoperative sessions consisting of motor performance evaluation and 3T-magnetic resonance imaging data acquisition. Based on additional postsurgical motor deficits, 6 patients were classified into “deficit group,” and 6 others were into “no deficit group.” Using resting-state functional magnetic resonance imaging (fMRI), the integrity of functional connectivity was evaluated by placing a seed in the ipsilesional primary motor area (M1). With motor task fMRI, hand and foot representations were identified in the M1 and lateral and medial PMs. Probabilistic tractography assessed anatomic connectivity in the cortico-cortical and corticofugal networks. RESULTS: Functional connectivity among M1 and lateral and medial PMs during resting-state fMRI was reduced postoperatively in the deficit group (P < .05, corrected) and preserved in the no deficit group. The deficit was unlikely to be attributable to surgical resection of specific anatomic connectivity. The amplitude of motor-evoked potential was maintained in available cases. These intraoperative observations agree with imaging findings suggesting preserved anatomic connectivity of the estimated corticofugal pathway. CONCLUSION: The present findings suggest that supplementary motor area syndrome is caused by disorganization of functional connectivity among cortical motor networks rather than resection of anatomic connectivity of corticofugal pathway.

Analysis of Lower Extremity Motor Capacity and Foot Plantar Pressure in Overweight and Obese Elderly Women.

Overweight, obesity and falls are major public health problems and old people are the biggest group suffering falls. 92 females were divided into the overweight or obesity (O) group (68.85 ± 3.85) and regular-weight (R) group (67.90 ± 4.02). Lower extremity motor capacity and plantar pressure were compared between the two groups. The IRB approval number is 20190804. (1) Functional Movement Screen and Fugl-Meyer Assessment scores in the O group were significantly lower than in the R group. The time to complete the Timed Up and Go test in the O group was significantly longer than in the R group. (2) Foot flat phase, double support distance, and left foot axis angle in the O group were significantly higher than in the R group. Distance and velocity, left-foot minimum subtalar joint angle and right-foot maximum subtalar joint angle in the O group were significantly shorter than in the R group. (3) Peak force, average force and pressure of metatarsal 1-4, mid-foot, heel medial and lateral, peak pressure of metatarsal l, midfoot, heel medial and lateral in the O group were significantly higher than in the R group. (p < 0.05). Overweight and obese elderly women have a lower sensorimotor function, flexibility and stability in functional movements, but higher loads on the foot.

EFEITOS DE TREINAMENTO COMPOSTO SOBRE A MOTRICIDADE ENTRE JOGADORES DE BASQUETE

ABSTRACT Introduction: In kinematics, one can measure the strength of movement ability by the time it takes to move a certain distance and the speed of movement of a person by the speed of displacement. Objective: To study the effect of compound training on the mobility of basketball players. Methods: A comparative experimental study was carried out on the sensitivity of basketball players, lasting 8 weeks. There were 30 basketball-playing volunteers randomly divided into two groups, while the control group performed routine activities. The control group implemented a training protocol composed of a ladder and ropes allied to conventional training. Results: After the experiment, the technical level of motricity in the control group and the experimental group showed differences over the result before the experiment (P&lt;0.05), and the experimental group showed a very significant difference (P&lt;0.01), improving their performance after the experiment. There are significant differences in the effects of different sensitivity training methods, the experimental group using rope ladder training methods greatly improved their foot agility and motor skill. Conclusion: Composite training involving a ladder and rope has a superior effect on the development of motor skill, ability, and foot agility in basketball players. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Characterization of Traumatic Injury During the Early COVID-19 Pandemic: Results From a National Healthcare Database.

Objective: To characterize traumatic injury patterns after stay-at-home orders were implemented in the United States in response to the coronavirus disease 2019 (COVID-19).Methods: A retrospective review of a convenience sample of patients from a national healthcare research database (TriNetX) was conducted from April 1, 2020, to June 30, 2020. Inclusion criteria included all patients with documentation of both injury pattern and mechanism of injury. A comparison was made to a matched pre-pandemic timeframe. Changes in percentage and rate ratio (RR) with a 95% confidence interval were reported. RRs were calculated using Poisson regression analysis.Results: A total of 238,661 patients in the control and 178,224 patients in the study cohorts were analyzed. Significant increases in assaults (RR: 1.17, 95% CI: 1.14, 1.20) and bicycle accidents (RR: 1.07, 95% CI: 1.04, 1.11) were noted. There was a relative increase in patients who were male (+1.78%) and white (+2.01%). More injuries were alcohol-related (+0.76%) and occurred at home (+0.79%). A decrease in motor vehicle accidents (-1.17%), foot and ankle injuries (-1.63%), and injuries occurring at sporting events (-0.54%) was noted.Conclusions: Changes in injury patterns were observed during the study period. During future crises, particular public health and injury prevention resources may be required to address assaults, substance abuse, and home safety.

CMT1B Patient with a Novel p.Arg98Leu MPZ Variant Mimicking Chronic Inflammatory Demyelinating Polyneuropathy on Electrodiagnostic Testing

Conduction block or temporal dispersion on motor nerve conduction studies (NCSs) are known as key features of chronic inflammatory demyelinating polyneuropathy. Some types of CharcotMarieTooth disease (CMT) have been also reported to show conduction block or temporal dispersion on NCS. We experienced a case who presented with slowly progressive motor weakness, sensory loss, foot deformity, and segmental demyelination on NCS. We confirmed her and her mother harboring CMT1B with a novel p.Arg98Leu MPZ variant.

Foundation forces caused by dynamic air gap torques of converter driven induction motors influenced by active vibration control: a theoretical analysis

In the paper, a theoretical analysis regarding foundation forces caused by dynamic air gap torques of converter-driven induction motors, influenced by active vibration control, is shown. Based on a plane model, where actuators are placed between the motor feet and steel frame foundation and where the vertical motor feet accelerations are controlled, a mathematical description in the time domain, Laplace domain, and Fourier domain is presented, as well as a block diagram for numerical simulation. A numerical example is shown, where a 2-pole induction motor (2 MW) is analyzed for different cases—motor directly mounted on a steel frame foundation (case 1), actuators between motor feet and foundation, operating passively (case 2) and actively (case 3). It could be shown, that with the presented active vibration control concept the foundation forces due to dynamic air gap torques can be clearly reduced.

Longitudinal study of foot pressures during real-world walking as infants develop from new to confident walkers

BackgroundOnset of walking in infants leads to regular cyclic loading of the plantar foot surface for the first time. This is a critical period for evolving motor skills and foot structure and function. Plantar pressure literature typically studies gait only once walking is established and under conditions that artificially constrain the walking direction and bouts compared to how infants move in the real-world. We therefore do not know how the foot is loaded when self-directed walking is first achieved and whether it changes as walking is practiced.Research questionHow do pressures on the plantar foot in real-world walking change from new to confident walking?MethodsFifty-seven infants participated in a two-site longitudinal study. Bespoke child-friendly spaces incorporated large pressure platforms and video. Data was collected at two milestones: new (403 days) and confident (481 days) walking. Steps were defined as walking straight or turning medially/laterally. Pressure variables were calculated for eight-foot regions and compared between milestones.ResultsConfident walking resulted in more steps (median: 18 v 35) and almost twice as many turning steps. During straight-line steps, confident walking increased peak pressures in the medial heel (median: 99.3 v 106.7kPa, p < .05) and lateral forefoot (median: 53.9 v 65.3kPa, p < .001) and reduced medial toe pressure (median: 98.1 v 80.0kPa, p < .05). Relative medial midfoot contact area reduced (median: 12.4 v 11.2%, p < .05) as absolute foot contact increased. A faster transition across stance and a reduced relative contact time in the forefoot were recorded in confident walking.SignificancePressures change rapidly as walking is initiated with significant differences in foot loading evident within an average 77 days. Importantly, these changes differ in straight and turning walking. Continued reliance on assessment of straight-line walking during early stages of ambulation likely fails to characterise 26% of steps experienced by infant feet.

Changes to foot pressure pattern in post-stroke individuals who have started to walk independently during the convalescent phase.

Abnormal foot contact patterns following stroke affect functional gait; however, objective analysis targeting independent walking is lacking. How do walking abilities and foot pressure patterns differ between post-stroke individuals who achieved independent walking and healthy controls? Secondarily, how do the abilities and patterns in post-stroke individuals change before and after achieving independent walking? Can these changes become criteria for permitting independent walking? Twenty-eight individuals with hemiplegia and 32 controls were enrolled. Motor dysfunction score (MDScore), walking speed (WSpeed), and foot pressure patterns were measured when they were first able to walk without orthosis or physical assistance (1st assessment) and when they achieved independent walking around discharge (2nd assessment). Foot pressure patterns were measured using insole-type foot pressure-measuring system. Ratios of partial foot pressure to body weight (%PFP), ratios of anteroposterior length of center of pressure (COP; %Long), and backward moving distance of COP to the foot length (%Backward) were calculated. Parameters during the 2nd assessment were compared with those of controls and those during the 1st assessment. During the 2nd assessment, relationships among the parameters, MDScore, and WSpeed were analyzed. During the 2nd assessment, no difference was observed in both %Long and %Backward between the non-paretic limbs and the controls. While the %Backward was higher, the %PFP of toes and %Long were lower in the paretic limb than in the controls. Although the %Backward was lower, both %PFP of toes and %Long of the paretic limb were higher in the 2nd assessment than in the 1st assessment. During the 2nd assessment, both %Long and % Backward values of the paretic limb moderately correlated with MDScore and WSpeed. After improvement of foot pressure in toes, both an increase in anteroposterior length and a decrease in backward moving of COP path were objective signs permitting independent walking.

An Evidence-Based Intelligent Method for Upper-Limb Motor Assessment via a VR Training System on Stroke Rehabilitation

Recently, virtual-reality (VR) has been an emerging technology, to this regard, it is widely employed by therapists to provide rich training tasks for the purpose of motor rehabilitation in clinics. Meanwhile, along with the progress of sensing technologies as means for the interaction with virtual environment, a large amount of data, such as motor trajectory, foot pressure or electromyography, is measured via VR-based motor training tasks and is considered as important clues for functional evaluations. However, very few study thoroughly applied the sensor-based data for motor assessment, instead, evaluation scales, such as TEMPA or Fugl-Meyer, were highly relied. In this study, a VR upper-limb motor training system was proposed for stroke rehabilitation. Clinical trials with 22 stroke patients were performed to exanimate the effectiveness of the propose VR system. Moreover, a variety of motor indicators derived via motion trajectory were proposed. Further, integrating multi-model data, such as motion trajectory, task performance and evaluation scales, machine-learning method was applied to develop evidence-based assessment models in order to evaluate upper-limb motor function. The results indicated that the proposed VR system was significantly effective for motor rehabilitation. Also, a few motor indicators were found significantly different between pre and post trials and were highly correlated with the evaluation scales. Finally, with the fusion of multi-model data, the accuracy rate of machine-learning assessment model was up to 92.72% which revealed its great potential for clinical use.

Functional MRI (fMRI) Evaluation of Hyperbaric Oxygen Therapy (HBOT) Efficacy in Chronic Cerebral Stroke: A Small Retrospective Consecutive Case Series.

Topics: Functional Magnetic Resonance Imaging (fMRI) evaluation of HyberBaric Oxygen Therapy (HBOT) effects on chronic cerebral stroke Patients (Pts). Introduction: Our aim was to evaluate with fMRI, in a 3 Tesla system, the functional effects of HBOT on the Central Nervous System (CNS) in four Pts with established ischaemic and haemorrhagic cerebral strokes (2 Pts each). To our knowledge, no author used fMRI technique for this purpose, till now. Methods: All four Pts underwent a fMRI study before and after 40 HBOT sessions, with a time window of a few days. They carried out two language (text listening, silent word-verb generation) and two motor (hand and foot movements) tasks (30 s On-Off block paradigms). Results: After HBOT, all Pts reported a clinical improvement, mostly concerning language fluency and motor paresis. fMRI analysis demonstrated an increase in both the extent and the statistical significance of most of the examined eloquent areas. Conclusions: These changes were consistent with the clinical improvement in all Pts, suggesting a possible role of fMRI in revealing neuronal functional correlates of neuronal plasticity and HBOT-related neoangiogenesis. Although only four Pts were examined, fMRI proved to be a sensitive, non-invasive and reliable modality for monitoring neuronal functional changes before and after HBOT.

Gait-synchronized oscillatory brain stimulation modulates common neural drives to ankle muscles in patients after stroke: A pilot study

The present study aimed to investigate the long-term effects of gait intervention with transcranial alternating current stimulation (tACS) synchronized with gait cycle frequency on the cortical control of muscle activity during gait, using coherence analyses, in patients after stroke. Eight chronic post-stroke patients participated in a single-blinded crossover study, and 7 patients completed the long-term intervention. Each patient received tACS over the primary motor cortex foot area on the affected side, which was synchronized with individual gait cycle frequency, and sham stimulation during treadmill gait in a random order. Electrical neuromuscular stimulation was used to assist the paretic ankle movement in both conditions. After gait intervention with tACS, beta band (15−35 Hz) coherence, which is considered to have a cortical origin, significantly increased in the paretic tibialis anterior (TA) muscle during 6-min of over-ground gait. The change in beta band coherence in the paretic TA muscle was positively correlated with the change in gait distance. These results indicate that gait intervention with tACS synchronized with gait cycle frequency may induce gait-specific plasticity that modulates the common neural drive to the TA motoneurons on the paretic side during gait and leads to changes in gait function in patients after stroke.

State space model for vibration control with arbitrary controller structures for soft mounted induction motors with sleeve bearings fixed on active motor foot mounts

AbstractIn the paper, a state space model for vibration control with arbitrary controller structures for soft mounted induction motors with sleeve bearings fixed on active motor foot mounts is shown. Besides the mathematical description of the forced vibrations caused by dynamic rotor eccentricity, a procedure is presented to derive the threshold of vibration stability. The challenge of the paper is the use of arbitrary controller structures with different feedback strategies – feedback of the motor feet displacements, velocities or accelerations – in combination with a special vibration system. This specialty is, that the stiffness and damping matrices depend on the rotor angular frequency Ω, which corresponds to the excitation angular frequency, when analyzing the forced vibration, and depend additionally on the natural angular frequency ωstab of the critical mode, when analyzing the threshold of stability. After the mathematical description is shown, a numerical example of a 2‐pole induction motor (power rating 2.4 MW) is presented, in which the threshold of stability is analyzed as well as the forced vibrations due to dynamic rotor eccentricity by investigating the bearing housing vibrations, the foundation vibrations and the actuator forces.

Analysis of Different Vibration Control Strategies for Soft Mounted Induction Motors with Sleeve Bearings Using Active Motor Foot Mounts

The paper presents a theoretical analysis of different vibration control strategies of soft mounted induction motors with sleeve bearings, using active motor foot mounts. After the vibration model is presented, different controllers in combination with different feedback strategies are mathematically investigated. The focus is here on the forced vibrations, caused by dynamic rotor eccentricity—rotor mass eccentricity, magnetic eccentricity and bent rotor deflection. After the mathematically coherences are described, a numerical example is shown, where the forced vibrations caused by bent rotor deflection are investigated, for different control strategies, where the mass matrix, the stiffness matrix and the damping matrix are influenced by different control parameters. The aim of the paper is to show the mathematically coherences and the possibility to influence the vibration behaviour, by different control strategies to optimize the vibration behaviour of soft mounted induction motors.

Resting-state functional connectivity of subcortical locomotor centers explains variance in walking capacity.

Walking capacity influences the quality of life and disability in normal aging and neurological disease, but the neural correlates remain unclear and subcortical locomotor regions identified in animals have been more challenging to assess in humans. Here we test whether resting-state functional MRI connectivity (rsFC) of midbrain and cerebellar locomotor regions (MLR and CLR) is associated with walking capacity among healthy adults. Using phenotypic and MRI data from the Nathan Kline Institute Rockland Sample (n =119, age 18-85), the association between walking capacity (6-min walk test distance) and rsFC was calculated from subcortical locomotor regions to 81 other gait-related regions of interest across the brain. Additional analyses assessed the independence and specificity of the results. Walking capacity was associated with higher rsFC between the MLR and superior frontal gyrus adjacent to the anterior cingulate cortex, higher rsFC between the MLR and paravermal cerebellum, and lower rsFC between the CLR and primary motor cortex foot area. These rsFC correlates were more strongly associated with walking capacity than phenotypic variables such as age, and together explained 25% of the variance in walking capacity. Results were specific to locomotor regions compared with the other brain regions. The rsFC of locomotor centers correlates with walking capacity among healthy adults. These locomotion-related biomarkers may prove useful in future work aimed at helping patients with reduced walking capacity.

Cyclostationary approach to detect flow-induced effects on vibration signals from centrifugal pumps

Abstract This study aims to investigate the mechanism of flow-induced effects on vibration signals from centrifugal pumps by combining computational fluid dynamics (CFD) and signal cyclostationarity. A pump vibration model is established as an amplitude-modulated (AM) model, and the modulation mechanism is elaborated in detail. A general AM model is mathematically analyzed with spectral correlation density and spectral coherence, and analytic solutions of modulation intensity are derived. Transient CFD simulations under design and off-design conditions are conducted to obtain the pressure pulsation in the volute and the radial fluid forces on the impeller. Then, vibration signals from the pump and motor feet with two acceleration transducers are processed by spectral coherence. The signature of second-order cyclostationarity is detected at the shaft rotating frequency and blade passing frequency (BPF). The mean spectral coherence is used to evaluate the intensity of the modulating signals produced by the flow-induced effects. Finally, the signal processing results are compared with the unsteady CFD results under design and off-design conditions. These comparisons show a good agreement. Therefore, this study confirms that the flow-induced signals calculated by CFD can be considered as modulating components for pump vibration signals. The results provide solid supporting theory for designing low vibration pumps.

Vibration control of soft mounted induction motors with sleeve bearings using active motor foot mounts: a theoretical analysis

In the paper, the vibration control of induction motors with sleeve bearings—mounted on soft steel frame foundations—using active motor foot mounts is analyzed. The presented model is based on a multibody model, considering electromagnetic influence, stiffness, and rotating damping of the rotor, stiffness and damping of the bearing housings with end shields, of the oil film in the sleeve bearings, and of the foundation. Additionally, the stiffness and damping of the motor foot mounts—which are positioned between the motor feet and the steel frame foundation—are considered, as well as the controlled forces which are applied in the vibration system by the motor foot mounts, using PD-controllers. The aim of the paper is to unite all these influences in a mathematical model, including the control system. Based on a numerical example, it can be shown that the vibration behavior of soft mounted induction motors can be clearly improved and that critical speeds in the speed range can be avoided, using active motor foot mounts.

Vibration control of large induction motors using actuators between motor feet and steel frame foundation

Abstract In the paper a theoretical analysis is deduced regarding vibration control of large induction motors – power rating ≥1 MW – with roller bearings, using actuators between motor feet and a soft steel frame foundation. Based on a multibody model, the mathematical coherences are shown, including the feedback control system. Afterwards a numerical example of a soft mounted, converter driven, 2-pole induction motor (1.6 MW) with ball bearings is presented, where the bearing housing vibrations and the foundation vibrations are analyzed with and without control system. It could be shown, that without vibration control system the operating speed range cannot be used completely because of resonances, caused by the soft foundation. Therefore, critical speed areas occur, where steady state operation is not possible. However, with the vibration control system, the whole operating speed range can be used. The aim of the paper is to show the capability of using a vibration control system with actuators between motor feet and a soft foundation, for avoiding off-limits areas for the operation speed of large induction motors.