Yosra Cherni1,2,3, Maryam Hajizadeh4, Fabien Dal Maso5,6, Nicolas A Turpin7. 1. School of Kinesiology, Faculty of Medicine, Université de Montréal, Montreal, Québec, Canada. Yosra.cherni@umontreal.ca. 2. Marie-Enfant Rehabilitation Center, UHC Sainte-Justine, Montreal, Québec, Canada. Yosra.cherni@umontreal.ca. 3. Interdisciplinary Research Center in Rehabilitation and Social Integration, Quebec City, Québec, Canada. Yosra.cherni@umontreal.ca. 4. Institute of Biomedical Engineering, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada. 5. School of Kinesiology, Faculty of Medicine, Université de Montréal, Montreal, Québec, Canada. 6. Interdisciplinary Center for Brain and Learning Research, Université de Montréal, Montréal, Québec, Canada. 7. Department of Sport Sciences (STAPS), IRISSE (EA 4075), UFR SHE, Université de La Réunion, Le Tampon, France.
Abstract
BACKGROUND: The Lokomat is a robotic device that has been suggested to make gait therapy easier, more comfortable, and more efficient. In this study, we asked whether the Lokomat promotes physiological muscle activation patterns, a fundamental question when considering motor learning and adaptation. METHODS: We investigated lower limb muscles coordination in terms of muscle activity level, muscle activity pattern similarity, and muscle synergy in 15 healthy participants walking at 3 km/h on either a treadmill or in a Lokomat at various guidance forces (GF: 30, 50 or 70%) and body weight supports (BWS: 30, 50 or 70% of participant's body weight). RESULTS: Walking in the Lokomat was associated with a greater activation level of the rectus femoris and vastus medialis (×2-3) compared to treadmill walking. The level of activity tended to be diminished in gastrocnemius and semi-tendinosus, which particularly affected the similarity with treadmill walking (normalized scalar product NSP = 0.7-0.8). GF and BWS independently altered the muscle activation pattern in terms of amplitude and shape. Increasing BWS decreased the level of activity in all but one muscle (the soleus). Increasing GF slightly improved the similarity with treadmill walking for the tibialis anterior and vastus medialis muscles. The muscle synergies (N = 4) were similar (NSP = 0.93-0.97), but a cross-validation procedure revealed an alteration by the Lokomat. The activation of these synergies differed (NSP = 0.74-0.82). CONCLUSION: The effects of GF and BWS are modest compared to the effect of the Lokomat itself, suggesting that Lokomat design should be improved to promote more typical muscle activity patterns.
BACKGROUND: The Lokomat is a robotic device that has been suggested to make gait therapy easier, more comfortable, and more efficient. In this study, we asked whether the Lokomat promotes physiological muscle activation patterns, a fundamental question when considering motor learning and adaptation. METHODS: We investigated lower limb muscles coordination in terms of muscle activity level, muscle activity pattern similarity, and muscle synergy in 15 healthy participants walking at 3 km/h on either a treadmill or in a Lokomat at various guidance forces (GF: 30, 50 or 70%) and body weight supports (BWS: 30, 50 or 70% of participant's body weight). RESULTS: Walking in the Lokomat was associated with a greater activation level of the rectus femoris and vastus medialis (×2-3) compared to treadmill walking. The level of activity tended to be diminished in gastrocnemius and semi-tendinosus, which particularly affected the similarity with treadmill walking (normalized scalar product NSP = 0.7-0.8). GF and BWS independently altered the muscle activation pattern in terms of amplitude and shape. Increasing BWS decreased the level of activity in all but one muscle (the soleus). Increasing GF slightly improved the similarity with treadmill walking for the tibialis anterior and vastus medialis muscles. The muscle synergies (N = 4) were similar (NSP = 0.93-0.97), but a cross-validation procedure revealed an alteration by the Lokomat. The activation of these synergies differed (NSP = 0.74-0.82). CONCLUSION: The effects of GF and BWS are modest compared to the effect of the Lokomat itself, suggesting that Lokomat design should be improved to promote more typical muscle activity patterns.
Authors: Noelia Chia Bejarano; Alessandra Pedrocchi; Antonio Nardone; Marco Schieppati; Walter Baccinelli; Marco Monticone; Giancarlo Ferrigno; Simona Ferrante Journal: Ann Biomed Eng Date: 2017-01-31 Impact factor: 3.934
Authors: Won Hyuk Chang; Min Su Kim; Jung Phil Huh; Peter K W Lee; Yun-Hee Kim Journal: Neurorehabil Neural Repair Date: 2011-11-15 Impact factor: 3.919
Authors: Filipe O Barroso; Diego Torricelli; Juan C Moreno; Julian Taylor; Julio Gomez-Soriano; Elisabeth Bravo-Esteban; Stefano Piazza; Cristina Santos; José L Pons Journal: J Neurophysiol Date: 2014-07-23 Impact factor: 2.714
Authors: Filipe O Barroso; Diego Torricelli; Elisabeth Bravo-Esteban; Julian Taylor; Julio Gómez-Soriano; Cristina Santos; Juan C Moreno; José L Pons Journal: Front Hum Neurosci Date: 2016-01-11 Impact factor: 3.169