1
|
Kim G, Sergi F. Modeling Neuromotor Adaptation to Pulsed Torque Assistance During Walking. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.19.580556. [PMID: 38979158 PMCID: PMC11230210 DOI: 10.1101/2024.02.19.580556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Multiple mechanisms of motor learning contribute to the response of individuals to robot-aided gait training, including error-based learning and use-dependent learning. Previous models described either of these mechanisms, but not both, and their relevance to gait training is unknown. In this paper, we establish the validity of existing models to describe the response of healthy individuals to robot-aided training of propulsion via a robotic exoskeleton, and propose a new model that accounts for both use-dependent and error-based learning. We formulated five state-space models to describe the stride-by-stride evolution of metrics of propulsion mechanics during and after robot-assisted training, applied by a hip/knee robotic exoskeleton for 200 consecutive strides. The five models included a single-state, a two-state, a two-state fast and slow, a use-dependent learning (UDL), and a newly-developed modified UDL model, requiring 4, 9, 5, 3, and 4 parameters, respectively. The coefficient of determination (R 2) and Akaike information criterion (AIC) values were calculated to quantify the goodness of fit of each model. Model fit was conducted both at the group and at the individual participant level. At the group level, the modified UDL model shows the best goodness-of-fit compared to other models in AIC values in 15/16 conditions. At the participant level, both the modified UDL model and the two-state model have significantly better goodness-of-fit compared to the other models. In summary, the modified UDL model is a simple 4-parameter model that achieves similar goodness-of-fit compared to a two-state model requiring 9 parameters. As such, the modified UDL model is a promising model to describe the effects of robot-aided gait training on propulsion mechanics.
Collapse
Affiliation(s)
- GilHwan Kim
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, USA
| | - Fabrizio Sergi
- Department of Biomedical Engineering, University of Delaware, Newark DE, 19713, USA
| |
Collapse
|
2
|
Livolsi C, Conti R, Guanziroli E, Friðriksson Þ, Alexandersson Á, Kristjánsson K, Esquenazi A, Molino Lova R, Romo D, Giovacchini F, Crea S, Molteni F, Vitiello N. An impairment-specific hip exoskeleton assistance for gait training in subjects with acquired brain injury: a feasibility study. Sci Rep 2022; 12:19343. [PMID: 36369462 PMCID: PMC9652374 DOI: 10.1038/s41598-022-23283-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 10/27/2022] [Indexed: 11/13/2022] Open
Abstract
This study was designed to investigate the feasibility and the potential effects on walking performance of a short gait training with a novel impairment-specific hip assistance (iHA) through a bilateral active pelvis orthosis (APO) in patients with acquired brain injury (ABI). Fourteen subjects capable of independent gait and exhibiting mild-to-moderate gait deficits, due to an ABI, were enrolled. Subjects presenting deficit in hip flexion and/or extension were included and divided into two groups based on the presence (group A, n = 6) or absence (group B, n = 8) of knee hyperextension during stance phase of walking. Two iHA-based profiles were developed for the groups. The protocol included two overground gait training sessions using APO, and two evaluation sessions, pre and post training. Primary outcomes were pre vs. post-training walking distance and steady-state speed in the 6-min walking test. Secondary outcomes were self-selected speed, joint kinematics and kinetics, gait symmetry and forward propulsion, assessed through 3D gait analysis. Following the training, study participants significantly increased the walked distance and average steady-state speed in the 6-min walking tests, both when walking with and without the APO. The increased walked distance surpassed the minimal clinically important difference for groups A and B, (respectively, 42 and 57 m > 34 m). In group A, five out of six subjects had decreased knee hyperextension at the post-training session (on average the peak of the knee extension angle was reduced by 36%). Knee flexion during swing phase increased, by 16% and 31%, for A and B groups respectively. Two-day gait training with APO providing iHA was effective and safe in improving walking performance and knee kinematics in ABI survivors. These preliminary findings suggest that this strategy may be viable for subject-specific post-ABI gait rehabilitation.
Collapse
Affiliation(s)
- Chiara Livolsi
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pontedera, Pisa, Italy.
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy.
| | | | - Eleonora Guanziroli
- Villa Beretta Rehabilitation Center, Valduce Hospital, Costa Masnaga, Lecco, Italy
| | | | | | | | - Alberto Esquenazi
- Department of PM&R, MossRehab and Einstein Healthcare Network, Elkins Park, PA, USA
| | | | | | | | - Simona Crea
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pontedera, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
- IRCCS Fondazione Don Carlo Gnocchi ONLUS, Florence, Italy
| | - Franco Molteni
- Villa Beretta Rehabilitation Center, Valduce Hospital, Costa Masnaga, Lecco, Italy
| | - Nicola Vitiello
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pontedera, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
- IRCCS Fondazione Don Carlo Gnocchi ONLUS, Florence, Italy
| |
Collapse
|
3
|
Pariser KM, Donlin MC, Downer KE, Higginson JS. Adaptive treadmill control can be manipulated to increase propulsive impulse while maintaining walking speed. J Biomech 2022; 133:110971. [PMID: 35121382 PMCID: PMC8891055 DOI: 10.1016/j.jbiomech.2022.110971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 11/18/2022]
Abstract
Adaptive treadmills (ATM) designed to promote increased propulsion may be an effective tool for gait training since propulsion is often impaired post-stroke. Our lab developed a novel ATM controller that adjusts belt speed via real-time changes in step length, propulsive impulse, and position. This study modified the relative importance of propulsion to step length in the controller to determine the effect of increased propulsive feedback gain on measures of propulsion and walking speed. Twenty-two participants completed five trials at their self-selected speed, each with a unique ATM controller. Walking speed, peak AGRF and PGRF, and AGRF, PGRF, and net impulse were compared between the modifications using one-way repeated measures ANOVAs at a significance level of 0.05. Participants chose similar walking speeds across all conditions (all p > 0.2730). There were no significant differences in peak AGRF (p = 0.1956) or PGRF (p = 0.5159) between conditions. AGRF impulse significantly increased as the gain on the propulsive impulse term was increased relative to the gain on step length (p < 0.0001) while PGRF and net impulse were similar across all conditions (p = 0.5487). Increasing the propulsive impulse gain essentially alters the treadmill environment by providing a controlled amount of resistance to increases in propulsive forces. Our findings demonstrate that the ATM can be modified to promote increased propulsive impulse while maintaining a consistent walking speed. Since increasing propulsion is a common goal of post-stroke gait training, these ATM modifications may improve the efficacy of the ATM for gait rehabilitation.
Collapse
Affiliation(s)
- Kayla M Pariser
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA.
| | - Margo C Donlin
- Department of Biomedical Engineering, University of Delaware, Newark, DE, USA
| | - Kaitlyn E Downer
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Jill S Higginson
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA; Department of Biomedical Engineering, University of Delaware, Newark, DE, USA
| |
Collapse
|
4
|
A Brake-Based Overground Gait Rehabilitation Device for Altering Propulsion Impulse Symmetry. SENSORS 2021; 21:s21196617. [PMID: 34640938 PMCID: PMC8512803 DOI: 10.3390/s21196617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/25/2021] [Accepted: 09/25/2021] [Indexed: 11/17/2022]
Abstract
This paper introduces a new device for gait rehabilitation, the gait propulsion trainer (GPT). It consists of two main components (a stationary device and a wearable system) that work together to apply periodic stance-phase resistance as the user walks overground. The stationary device provides the resistance forces via a cable that tethers the user’s pelvis to a magnetic-particle brake. The wearable system detects gait events via foot switches to control the timing of the resistance forces. A hardware verification test confirmed that the GPT functions as intended. We conducted a pilot study in which one healthy adult and one stroke survivor walked with the GPT with increasing resistance levels. As hypothesized, the periodic stance-phase resistance caused the healthy participant to walk asymmetrically, with greatly reduced propulsion impulse symmetry; as GPT resistance increased, the walking speed also decreased, and the propulsion impulse appeared to increase for both legs. In contrast, the stroke participant responded to GPT resistance by walking faster and more symmetrically in terms of both propulsion impulse and step length. Thus, this paper shows promising results of short-term training with the GPT, and more studies will follow to explore its long-term effects on hemiparetic gait.
Collapse
|