Adaptive body weight support controls human activity during robot-aided gait training

This study introduces the development of a new body weight support system using pneumatic actuators for gait training. The main scope of this work is to provide a new design, validation, and assessment for active body weight support systems to reproduce a subject’s normal walking behavior. Based on the assessments and its evaluations, the novel body weight support system using pneumatic muscle actuators shows many advantageous characteristics, such as simplicity, low cost, maintenance of a constant unloading force, and ease of control of the supported force. The capability of the novel body weight support system to generate unloading forces that track the center of pressure, because it switches from left to right and vice versa as the subject walks, is especially interesting.

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Advantage in muscle activation in gait with support of body weight in spinal cord injury

Fisioterapia em Movimento ◽

10.1590/1980-5918.031.ao29 ◽

2018 ◽

Vol 31 (0) ◽

Author(s):

Jéssica Saccol Borin ◽

Tânia Valdameri Capelari ◽

Melissa Grigol Goldhardt ◽

Márcia Cristina Issa ◽

Diego Antônio Pereira Bica dos Santos ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Body Weight ◽

Muscle Activation ◽

Gait Training ◽

Treadmill Training ◽

Body Weight Support ◽

Weight Support ◽

Cord Injury ◽

Injured Patients

Abstract Introduction: The locomotor training with body weight support has been proposed as an alternative for the rehabilitation of people with spinal cord injury, in order to develop most of the residual potential of the body. Objective: To compare the levels of muscle activation of the main muscle involved in gait during body weight-supported treadmill training and body weight-supported overground training in incomplete spinal cord injured patients. Methods: It was a prospective cross-sectional study, in which 11 incomplete injured patients were submitted to two modalities of gait with body weight support, the first one on the treadmill (two different speeds: 1 and 4km/h), and the second one with the walker on fixed floor. The electromyographical acquisition was done in the rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL) and gluteus maximus (GM). Results: There was a greater muscle activation of all muscles analyzed in the treadmill training as compared to the over groundtraining, both at 4 km/h (RF: p=0.00), (VM: p=0.00), (VL: p=0.00) e (GM: p=0.00) and at 1km/h (RF: p=0.00), (VM: p=0.00), (VL: p=0.00) e (GM: p=0.00). When comparing the two modalities of treadmill training, at 4 and 1km/h, there was no statically significant difference between them (RF: p=0.36), (VM: p=1.00), (VL: p=1.00) e (GM: p=0.16). Conclusion: The gait training with body weight support is more effective in activating the muscles involved in the gait training on treadmill compared to overground training in patients with incomplete spinal cord injury.

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Direction of gait asymmetry following stroke determines acute response to locomotor task

10.1101/588103 ◽

2019 ◽

Author(s):

Virginia L Little ◽

Lindsay A Perry ◽

Mae WV Mercado ◽

Steven A Kautz ◽

Carolynn Patten

Keyword(s):

Body Weight ◽

Step Length ◽

Gait Training ◽

Body Weight Support ◽

Locomotor Training ◽

Weight Support ◽

Gait Dysfunction ◽

Gait Asymmetry ◽

Differential Responses ◽

Task Conditions

AbstractBackgroundGiven the prevalence of gait dysfunction following stroke, walking recovery is a primary goal of rehabilitation. However, current gait rehabilitation approaches fail to demonstrate consistent benefits. Furthermore, asymmetry is a prominent feature of gait dysfunction following stroke. Differential patterns of gait asymmetry may respond differently to gait training parameters.ObjectiveThe purpose of this study was to determine whether differential responses to locomotor task condition occur on the basis of direction of step length asymmetry (Symmetrical, NPshort, Pshort) observed during overground walking.MethodsParticipants first walked overground at their self-selected walking speed. Overground data were compared against three task conditions all tested during treadmill walking: self-selected speed with 0% body weight support (TM); self-selected speed with 30% body weight support (BWS); and fastest comfortable speed with 30% body weight support and nonparetic leg guidance (GuidanceNP). Our primary outcomes were: step length, single limb support duration, and stride length.ResultsWe identified differences in the response to locomotor task conditions for each step length asymmetry subgroup. GuidanceNPinduced an acute spatial symmetry only in the NPshortgroup and temporal symmetry in the Symmetrical group.ConclusionsTask conditions consistent with locomotor training do not produce uniform effects across subpatterns of gait asymmetry. We identified differential responses to locomotor task conditions between groups with distinct asymmetry patterns, suggesting these subgroups may require unique intervention strategies. Despite group differences in asymmetry characteristics, improvements in symmetry noted in the Symmetrical and NPshortgroups were driven by changes in both the paretic and nonparetic limbs.

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Gastrocnemius Medialis Contractile Behavior Is Preserved During 30% Body Weight Supported Gait Training

Frontiers in Sports and Active Living ◽

10.3389/fspor.2020.614559 ◽

2021 ◽

Vol 2 ◽

Author(s):

Charlotte Richter ◽

Bjoern Braunstein ◽

Benjamin Staeudle ◽

Julia Attias ◽

Alexander Suess ◽

...

Keyword(s):

Body Weight ◽

Elastic Element ◽

Gait Training ◽

Joint Kinematics ◽

Body Weight Support ◽

Gait Patterns ◽

Gastrocnemius Medialis ◽

Series Elastic Element ◽

Weight Support ◽

Series Elastic

Rehabilitative body weight supported gait training aims at restoring walking function as a key element in activities of daily living. Studies demonstrated reductions in muscle and joint forces, while kinematic gait patterns appear to be preserved with up to 30% weight support. However, the influence of body weight support on muscle architecture, with respect to fascicle and series elastic element behavior is unknown, despite this having potential clinical implications for gait retraining. Eight males (31.9 ± 4.7 years) walked at 75% of the speed at which they typically transition to running, with 0% and 30% body weight support on a lower-body positive pressure treadmill. Gastrocnemius medialis fascicle lengths and pennation angles were measured via ultrasonography. Additionally, joint kinematics were analyzed to determine gastrocnemius medialis muscle–tendon unit lengths, consisting of the muscle's contractile and series elastic elements. Series elastic element length was assessed using a muscle–tendon unit model. Depending on whether data were normally distributed, a paired t-test or Wilcoxon signed rank test was performed to determine if body weight supported walking had any effects on joint kinematics and fascicle–series elastic element behavior. Walking with 30% body weight support had no statistically significant effect on joint kinematics and peak series elastic element length. Furthermore, at the time when peak series elastic element length was achieved, and on average across the entire stance phase, muscle–tendon unit length, fascicle length, pennation angle, and fascicle velocity were unchanged with respect to body weight support. In accordance with unchanged gait kinematics, preservation of fascicle–series elastic element behavior was observed during walking with 30% body weight support, which suggests transferability of gait patterns to subsequent unsupported walking.

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