2010
Craven, C; Gollee, H; Purcell, M; Allan, D
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 071, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISSN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_071b,
title = {Cardiopulmonary responses to active and electrically stimulated stepping, with robotics assistance in early-stage spinal cord injury},
author = {C Craven and H Gollee and M Purcell and D Allan},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
issn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {071},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {Early stage spinal cord injury involves a period of bed rest and low activity. Subsequent co-factors such as low blood pressure and muscle atrophy lead to a decrease in cardiopulmonary fitness. It is proposed here that the introduction of an appropriate training programme during the early stage of injury may attenuate this loss of fitness. This work examined the cardiopulmonary responses of three motor complete and three motor incomplete spinal cord injured subjects to a number of robotics-assisted stepping exercises. Subjects participated in periods of passive, active and electrically stimulated stepping. Increases in a number of cardiopulmonary parameters were observed with some subjects, in response to these exercises. These results show that those with an incomplete SCI may benefit from this form training during the early phase of injury.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
Early stage spinal cord injury involves a period of bed rest and low activity. Subsequent co-factors such as low blood pressure and muscle atrophy lead to a decrease in cardiopulmonary fitness. It is proposed here that the introduction of an appropriate training programme during the early stage of injury may attenuate this loss of fitness. This work examined the cardiopulmonary responses of three motor complete and three motor incomplete spinal cord injured subjects to a number of robotics-assisted stepping exercises. Subjects participated in periods of passive, active and electrically stimulated stepping. Increases in a number of cardiopulmonary parameters were observed with some subjects, in response to these exercises. These results show that those with an incomplete SCI may benefit from this form training during the early phase of injury.
Curtis, C A; Chong, S L; Mushahwar, V K
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 069, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISSN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_069b,
title = {The effects of intermittent electrical stimulation with varying load and stimulation paradigms for the prevention of deep tissue injury},
author = {C A Curtis and S L Chong and V K Mushahwar},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
issn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {069},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {A pressure ulcer is a medical complication that arises in persons with decreased mobility and/or sensation. Deep pressure ulcers starting at the bone-muscle interface are the most dangerous, as they can cause extensive damage before showing any signs at the skin surface. We proposed a novel intervention called intermittent electrical stimulation (IES) for the prevention of deep tissue injury. In this study, we tested the effects of four paradigms of IES and one conventional pressure relief paradigm in preventing the formation of deep pressure ulcers in rats. Pressures equivalent to 18%, 28%, or 38% of the body weight of each rat were applied to the triceps surae muscle in one limb. Treatment groups received IES every ten minutes for either 5s or 10s and maximal or moderate contraction, or complete pressure removal every ten minutes for 10s. The results showed that conventional pressure relief, emulating a wheelchair pushup every ten minutes, was inadequate for the prevention of deep tissue injury. In contrast, all IES paradigms were equally effective in significantly reducing the extent of deep muscle damage caused by 28% or 38% BW pressure application. This outcome provides important information for the development of an alternative method for pressure ulcer prevention.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
A pressure ulcer is a medical complication that arises in persons with decreased mobility and/or sensation. Deep pressure ulcers starting at the bone-muscle interface are the most dangerous, as they can cause extensive damage before showing any signs at the skin surface. We proposed a novel intervention called intermittent electrical stimulation (IES) for the prevention of deep tissue injury. In this study, we tested the effects of four paradigms of IES and one conventional pressure relief paradigm in preventing the formation of deep pressure ulcers in rats. Pressures equivalent to 18%, 28%, or 38% of the body weight of each rat were applied to the triceps surae muscle in one limb. Treatment groups received IES every ten minutes for either 5s or 10s and maximal or moderate contraction, or complete pressure removal every ten minutes for 10s. The results showed that conventional pressure relief, emulating a wheelchair pushup every ten minutes, was inadequate for the prevention of deep tissue injury. In contrast, all IES paradigms were equally effective in significantly reducing the extent of deep muscle damage caused by 28% or 38% BW pressure application. This outcome provides important information for the development of an alternative method for pressure ulcer prevention.
Davis, G; Estigoni, E; Fornusek, C; Smith, R
Effects of Recovery after Fatigue on M-wave vs Torque Relationships during Isometric FES-induced Contractions Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 072, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISSN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_072b,
title = {Effects of Recovery after Fatigue on M-wave vs Torque Relationships during Isometric FES-induced Contractions},
author = {G Davis and E Estigoni and C Fornusek and R Smith},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
issn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {072},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {FES-evoked electromyography (eEMG) has been used to characterize the onset of fatigue in individuals with spinal cord injury (SCI). However, the relationship between eEMG and muscle torque is not always consistent amongst individuals nor over repeated bouts of FES-exercise. Purpose: This study investigated whether the relationship between Torque and eEMG variables remained constant after short recovery periods between repeated bouts of isometric FES contractions. Methods: Six SCI males volunteered to participate in this study. We employed a custom-built evoked EMG acquisition system to control FES and synchronize myoelectric signals with torque data from a Biodex muscle dynamometer. Each subject performed 3 FES-induced isometric contractions with the knee at 60 deg separated by recovery periods. Results: Inspection of time curves revealed that key m-wave variables recovered at a faster rate than did muscle torque during and after the 2nd and 3rd contractions. Different patterns emerged between individuals, but there was a clear trend for eEMG data to "recover" more quickly after repeated muscle stimulation. Conclusions: Since the relationships between m-waves and muscle torque was not consistent between the 3 contractions, the potential use of eEMG signals as a proxy for muscle fatigue must be further investigated. Clinicians may need to re-plan their strategies for using eEMG as feedback for muscle fatigue in SCI individuals and further explore the different causes of fatigue during FES-induced exercise.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
FES-evoked electromyography (eEMG) has been used to characterize the onset of fatigue in individuals with spinal cord injury (SCI). However, the relationship between eEMG and muscle torque is not always consistent amongst individuals nor over repeated bouts of FES-exercise. Purpose: This study investigated whether the relationship between Torque and eEMG variables remained constant after short recovery periods between repeated bouts of isometric FES contractions. Methods: Six SCI males volunteered to participate in this study. We employed a custom-built evoked EMG acquisition system to control FES and synchronize myoelectric signals with torque data from a Biodex muscle dynamometer. Each subject performed 3 FES-induced isometric contractions with the knee at 60 deg separated by recovery periods. Results: Inspection of time curves revealed that key m-wave variables recovered at a faster rate than did muscle torque during and after the 2nd and 3rd contractions. Different patterns emerged between individuals, but there was a clear trend for eEMG data to "recover" more quickly after repeated muscle stimulation. Conclusions: Since the relationships between m-waves and muscle torque was not consistent between the 3 contractions, the potential use of eEMG signals as a proxy for muscle fatigue must be further investigated. Clinicians may need to re-plan their strategies for using eEMG as feedback for muscle fatigue in SCI individuals and further explore the different causes of fatigue during FES-induced exercise.
Carraro, U; Kern, H
Home-based FES in SCI: Recovery of tetanic contractility drives the structural improvements of denervated muscles Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 065, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISSN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_065b,
title = {Home-based FES in SCI: Recovery of tetanic contractility drives the structural improvements of denervated muscles},
author = {U Carraro and H Kern},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
issn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {065},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {Spinal-cord injury causes muscle atrophy, which is particularly severe when lower motor neurons are involved. We performed a longitudinal study in 25 patients suffering from complete lesion of Conus Cauda from 0.7 to 8.7 years comparing functional and structural thigh muscle properties before and after 2 years of home-based training by Functional Electrical Stimulation (h-b FES). Muscles were electrically stimulated by means of large surface electrodes and a custom-designed stimulator. The poor excitability of the lower motor neuron denervated muscles was improved first by twitch-contraction training and then by tetanic contractions elicited against progressively increased loading. Improvement of thigh muscle properties was estimated by transverse computer tomography scan and force measurements. In addition, needle biopsies of vastus lateralis were harvested before and after the two-years of h-b FES. Twenty out of 25 patients completed the two year h-b FES program, which resulted in: 1. significant increase of muscle size (the cross sectional area of the quadriceps increased from 28.2textpm8.1 to 38.1textpm12.7 cm2, p<0.001, +35%, and the mean diameter of muscle fibers from 16.6textpm14.3 to 29.1textpm23.3 um, p<0.001, +75%), accompanied by improvements of the ultra-structural organization of contractile material; and 2. a significant increase in force output during electrical stimulation (from 0.8textpm1.3 to 10.3textpm8.1 Nm, p<0.001, + 1187%). Important benefits for the patients are the improved cosmetic appearance of lower extremities and the enhanced cushioning effect for seating. The EU Project Rise shows that "home-based FES" is a safe and effective therapy that may maintain life-long physical exercise by active muscle contraction (FES is the only option for denervated muscle) to be used as a procedure to recover tetanic contractility of denervated muscle, and to counteract muscle atrophy in order to prevent long-term complications of SCI.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
Spinal-cord injury causes muscle atrophy, which is particularly severe when lower motor neurons are involved. We performed a longitudinal study in 25 patients suffering from complete lesion of Conus Cauda from 0.7 to 8.7 years comparing functional and structural thigh muscle properties before and after 2 years of home-based training by Functional Electrical Stimulation (h-b FES). Muscles were electrically stimulated by means of large surface electrodes and a custom-designed stimulator. The poor excitability of the lower motor neuron denervated muscles was improved first by twitch-contraction training and then by tetanic contractions elicited against progressively increased loading. Improvement of thigh muscle properties was estimated by transverse computer tomography scan and force measurements. In addition, needle biopsies of vastus lateralis were harvested before and after the two-years of h-b FES. Twenty out of 25 patients completed the two year h-b FES program, which resulted in: 1. significant increase of muscle size (the cross sectional area of the quadriceps increased from 28.2textpm8.1 to 38.1textpm12.7 cm2, p<0.001, +35%, and the mean diameter of muscle fibers from 16.6textpm14.3 to 29.1textpm23.3 um, p<0.001, +75%), accompanied by improvements of the ultra-structural organization of contractile material; and 2. a significant increase in force output during electrical stimulation (from 0.8textpm1.3 to 10.3textpm8.1 Nm, p<0.001, + 1187%). Important benefits for the patients are the improved cosmetic appearance of lower extremities and the enhanced cushioning effect for seating. The EU Project Rise shows that "home-based FES" is a safe and effective therapy that may maintain life-long physical exercise by active muscle contraction (FES is the only option for denervated muscle) to be used as a procedure to recover tetanic contractility of denervated muscle, and to counteract muscle atrophy in order to prevent long-term complications of SCI.
Alvarado-Pacheco, L E; Ogilvie, R J; Chong, S L; Mushahwar, V K
Active arm involvement in the rehabilitation of walking after spinal cord injury: a case study Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 067, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_067,
title = {Active arm involvement in the rehabilitation of walking after spinal cord injury: a case study},
author = {L E Alvarado-Pacheco and R J Ogilvie and S L Chong and V K Mushahwar},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {067},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {The purpose of this study is to evaluate the outcomes of actively involving the arms along with the legs in a rehabilitation program to improve walking after incomplete spinal cord injury (iSCI). Interlimb modulation characterized by the swinging of the arms during walking in humans, involves neuronal pathways between the arm and leg control regions in the spinal cord. However, the arms are not actively involved in locomotion rehabilitation protocols currently in practice. We evaluated this new intervention in one subject with chronic iSCI using a combined arm/leg FES-assisted cycling ergometer. After completing 12 weeks of FES-assisted arm /leg cycling, the participant improved his overground walking ability and now requires one less assistive device for walking more than 10m. Walking speed improved by 23% (10m test), and endurance by 24% (6min test). Improvements in balance according to the Berg scale were observed. Beneficial changes in the activation pattern of leg muscles as well as in foot clearance are reported. The preliminary results suggest that this novel intervention may be effective in improving overground walking in people with iSCI.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
The purpose of this study is to evaluate the outcomes of actively involving the arms along with the legs in a rehabilitation program to improve walking after incomplete spinal cord injury (iSCI). Interlimb modulation characterized by the swinging of the arms during walking in humans, involves neuronal pathways between the arm and leg control regions in the spinal cord. However, the arms are not actively involved in locomotion rehabilitation protocols currently in practice. We evaluated this new intervention in one subject with chronic iSCI using a combined arm/leg FES-assisted cycling ergometer. After completing 12 weeks of FES-assisted arm /leg cycling, the participant improved his overground walking ability and now requires one less assistive device for walking more than 10m. Walking speed improved by 23% (10m test), and endurance by 24% (6min test). Improvements in balance according to the Berg scale were observed. Beneficial changes in the activation pattern of leg muscles as well as in foot clearance are reported. The preliminary results suggest that this novel intervention may be effective in improving overground walking in people with iSCI.
Craven, C; Gollee, H; Purcell, M; Allan, D
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 071, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_071,
title = {Cardiopulmonary responses to active and electrically stimulated stepping, with robotics assistance in early-stage spinal cord injury},
author = {C Craven and H Gollee and M Purcell and D Allan},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {071},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {Early stage spinal cord injury involves a period of bed rest and low activity. Subsequent co-factors such as low blood pressure and muscle atrophy lead to a decrease in cardiopulmonary fitness. It is proposed here that the introduction of an appropriate training programme during the early stage of injury may attenuate this loss of fitness. This work examined the cardiopulmonary responses of three motor complete and three motor incomplete spinal cord injured subjects to a number of robotics-assisted stepping exercises. Subjects participated in periods of passive, active and electrically stimulated stepping. Increases in a number of cardiopulmonary parameters were observed with some subjects, in response to these exercises. These results show that those with an incomplete SCI may benefit from this form training during the early phase of injury.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
Early stage spinal cord injury involves a period of bed rest and low activity. Subsequent co-factors such as low blood pressure and muscle atrophy lead to a decrease in cardiopulmonary fitness. It is proposed here that the introduction of an appropriate training programme during the early stage of injury may attenuate this loss of fitness. This work examined the cardiopulmonary responses of three motor complete and three motor incomplete spinal cord injured subjects to a number of robotics-assisted stepping exercises. Subjects participated in periods of passive, active and electrically stimulated stepping. Increases in a number of cardiopulmonary parameters were observed with some subjects, in response to these exercises. These results show that those with an incomplete SCI may benefit from this form training during the early phase of injury.
Curtis, C A; Chong, S L; Mushahwar, V K
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 069, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_069,
title = {The effects of intermittent electrical stimulation with varying load and stimulation paradigms for the prevention of deep tissue injury},
author = {C A Curtis and S L Chong and V K Mushahwar},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {069},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {A pressure ulcer is a medical complication that arises in persons with decreased mobility and/or sensation. Deep pressure ulcers starting at the bone-muscle interface are the most dangerous, as they can cause extensive damage before showing any signs at the skin surface. We proposed a novel intervention called intermittent electrical stimulation (IES) for the prevention of deep tissue injury. In this study, we tested the effects of four paradigms of IES and one conventional pressure relief paradigm in preventing the formation of deep pressure ulcers in rats. Pressures equivalent to 18%, 28%, or 38% of the body weight of each rat were applied to the triceps surae muscle in one limb. Treatment groups received IES every ten minutes for either 5s or 10s and maximal or moderate contraction, or complete pressure removal every ten minutes for 10s. The results showed that conventional pressure relief, emulating a wheelchair pushup every ten minutes, was inadequate for the prevention of deep tissue injury. In contrast, all IES paradigms were equally effective in significantly reducing the extent of deep muscle damage caused by 28% or 38% BW pressure application. This outcome provides important information for the development of an alternative method for pressure ulcer prevention.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
A pressure ulcer is a medical complication that arises in persons with decreased mobility and/or sensation. Deep pressure ulcers starting at the bone-muscle interface are the most dangerous, as they can cause extensive damage before showing any signs at the skin surface. We proposed a novel intervention called intermittent electrical stimulation (IES) for the prevention of deep tissue injury. In this study, we tested the effects of four paradigms of IES and one conventional pressure relief paradigm in preventing the formation of deep pressure ulcers in rats. Pressures equivalent to 18%, 28%, or 38% of the body weight of each rat were applied to the triceps surae muscle in one limb. Treatment groups received IES every ten minutes for either 5s or 10s and maximal or moderate contraction, or complete pressure removal every ten minutes for 10s. The results showed that conventional pressure relief, emulating a wheelchair pushup every ten minutes, was inadequate for the prevention of deep tissue injury. In contrast, all IES paradigms were equally effective in significantly reducing the extent of deep muscle damage caused by 28% or 38% BW pressure application. This outcome provides important information for the development of an alternative method for pressure ulcer prevention.
Davis, G; Estigoni, E; Fornusek, C; Smith, R
Effects of Recovery after Fatigue on M-wave vs Torque Relationships during Isometric FES-induced Contractions Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 072, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_072,
title = {Effects of Recovery after Fatigue on M-wave vs Torque Relationships during Isometric FES-induced Contractions},
author = {G Davis and E Estigoni and C Fornusek and R Smith},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {072},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {FES-evoked electromyography (eEMG) has been used to characterize the onset of fatigue in individuals with spinal cord injury (SCI). However, the relationship between eEMG and muscle torque is not always consistent amongst individuals nor over repeated bouts of FES-exercise. Purpose: This study investigated whether the relationship between Torque and eEMG variables remained constant after short recovery periods between repeated bouts of isometric FES contractions. Methods: Six SCI males volunteered to participate in this study. We employed a custom-built evoked EMG acquisition system to control FES and synchronize myoelectric signals with torque data from a Biodex muscle dynamometer. Each subject performed 3 FES-induced isometric contractions with the knee at 60 deg separated by recovery periods. Results: Inspection of time curves revealed that key m-wave variables recovered at a faster rate than did muscle torque during and after the 2nd and 3rd contractions. Different patterns emerged between individuals, but there was a clear trend for eEMG data to "recover" more quickly after repeated muscle stimulation. Conclusions: Since the relationships between m-waves and muscle torque was not consistent between the 3 contractions, the potential use of eEMG signals as a proxy for muscle fatigue must be further investigated. Clinicians may need to re-plan their strategies for using eEMG as feedback for muscle fatigue in SCI individuals and further explore the different causes of fatigue during FES-induced exercise.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
FES-evoked electromyography (eEMG) has been used to characterize the onset of fatigue in individuals with spinal cord injury (SCI). However, the relationship between eEMG and muscle torque is not always consistent amongst individuals nor over repeated bouts of FES-exercise. Purpose: This study investigated whether the relationship between Torque and eEMG variables remained constant after short recovery periods between repeated bouts of isometric FES contractions. Methods: Six SCI males volunteered to participate in this study. We employed a custom-built evoked EMG acquisition system to control FES and synchronize myoelectric signals with torque data from a Biodex muscle dynamometer. Each subject performed 3 FES-induced isometric contractions with the knee at 60 deg separated by recovery periods. Results: Inspection of time curves revealed that key m-wave variables recovered at a faster rate than did muscle torque during and after the 2nd and 3rd contractions. Different patterns emerged between individuals, but there was a clear trend for eEMG data to "recover" more quickly after repeated muscle stimulation. Conclusions: Since the relationships between m-waves and muscle torque was not consistent between the 3 contractions, the potential use of eEMG signals as a proxy for muscle fatigue must be further investigated. Clinicians may need to re-plan their strategies for using eEMG as feedback for muscle fatigue in SCI individuals and further explore the different causes of fatigue during FES-induced exercise.
Carraro, U; Kern, H
Home-based FES in SCI: Recovery of tetanic contractility drives the structural improvements of denervated muscles Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 065, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_065,
title = {Home-based FES in SCI: Recovery of tetanic contractility drives the structural improvements of denervated muscles},
author = {U Carraro and H Kern},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {065},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {Spinal-cord injury causes muscle atrophy, which is particularly severe when lower motor neurons are involved. We performed a longitudinal study in 25 patients suffering from complete lesion of Conus Cauda from 0.7 to 8.7 years comparing functional and structural thigh muscle properties before and after 2 years of home-based training by Functional Electrical Stimulation (h-b FES). Muscles were electrically stimulated by means of large surface electrodes and a custom-designed stimulator. The poor excitability of the lower motor neuron denervated muscles was improved first by twitch-contraction training and then by tetanic contractions elicited against progressively increased loading. Improvement of thigh muscle properties was estimated by transverse computer tomography scan and force measurements. In addition, needle biopsies of vastus lateralis were harvested before and after the two-years of h-b FES. Twenty out of 25 patients completed the two year h-b FES program, which resulted in: 1. significant increase of muscle size (the cross sectional area of the quadriceps increased from 28.2textpm8.1 to 38.1textpm12.7 cm2, p<0.001, +35%, and the mean diameter of muscle fibers from 16.6textpm14.3 to 29.1textpm23.3 um, p<0.001, +75%), accompanied by improvements of the ultra-structural organization of contractile material; and 2. a significant increase in force output during electrical stimulation (from 0.8textpm1.3 to 10.3textpm8.1 Nm, p<0.001, + 1187%). Important benefits for the patients are the improved cosmetic appearance of lower extremities and the enhanced cushioning effect for seating. The EU Project Rise shows that "home-based FES" is a safe and effective therapy that may maintain life-long physical exercise by active muscle contraction (FES is the only option for denervated muscle) to be used as a procedure to recover tetanic contractility of denervated muscle, and to counteract muscle atrophy in order to prevent long-term complications of SCI.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
Spinal-cord injury causes muscle atrophy, which is particularly severe when lower motor neurons are involved. We performed a longitudinal study in 25 patients suffering from complete lesion of Conus Cauda from 0.7 to 8.7 years comparing functional and structural thigh muscle properties before and after 2 years of home-based training by Functional Electrical Stimulation (h-b FES). Muscles were electrically stimulated by means of large surface electrodes and a custom-designed stimulator. The poor excitability of the lower motor neuron denervated muscles was improved first by twitch-contraction training and then by tetanic contractions elicited against progressively increased loading. Improvement of thigh muscle properties was estimated by transverse computer tomography scan and force measurements. In addition, needle biopsies of vastus lateralis were harvested before and after the two-years of h-b FES. Twenty out of 25 patients completed the two year h-b FES program, which resulted in: 1. significant increase of muscle size (the cross sectional area of the quadriceps increased from 28.2textpm8.1 to 38.1textpm12.7 cm2, p<0.001, +35%, and the mean diameter of muscle fibers from 16.6textpm14.3 to 29.1textpm23.3 um, p<0.001, +75%), accompanied by improvements of the ultra-structural organization of contractile material; and 2. a significant increase in force output during electrical stimulation (from 0.8textpm1.3 to 10.3textpm8.1 Nm, p<0.001, + 1187%). Important benefits for the patients are the improved cosmetic appearance of lower extremities and the enhanced cushioning effect for seating. The EU Project Rise shows that "home-based FES" is a safe and effective therapy that may maintain life-long physical exercise by active muscle contraction (FES is the only option for denervated muscle) to be used as a procedure to recover tetanic contractility of denervated muscle, and to counteract muscle atrophy in order to prevent long-term complications of SCI.
Nekoular, V; Erfanian, A
Optimal walking trajectories estimation using wavelet neural network for FES-assisted arm-supported paraplegic walking Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 068, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_068,
title = {Optimal walking trajectories estimation using wavelet neural network for FES-assisted arm-supported paraplegic walking},
author = {V Nekoular and A Erfanian},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {068},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {One major limitation of arm-supported walking using functional electrical stimulation in paraplegic subjects is the high energy expenditure and the high upper body effort. One major factor that affects the energy expenditure and the high upper body effort during arm-supported FES-assisted walking is the gait pattern. To obtain a gait pattern that lead to minimum handle reaction force (HRF), a method is proposed to find the optimal gait patterns that lead to minimum HRF. For this purpose, a neural network model of the human walking is presented to relate the joint angles to the HRF. Using the neural model, an optimal walking trajectory is determined to minimize the HRF. The experiments were conducted on two paraplegic subjects. The results show that the HRF obtained for optimal gait pattern is less than the measured HRF.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
One major limitation of arm-supported walking using functional electrical stimulation in paraplegic subjects is the high energy expenditure and the high upper body effort. One major factor that affects the energy expenditure and the high upper body effort during arm-supported FES-assisted walking is the gait pattern. To obtain a gait pattern that lead to minimum handle reaction force (HRF), a method is proposed to find the optimal gait patterns that lead to minimum HRF. For this purpose, a neural network model of the human walking is presented to relate the joint angles to the HRF. Using the neural model, an optimal walking trajectory is determined to minimize the HRF. The experiments were conducted on two paraplegic subjects. The results show that the HRF obtained for optimal gait pattern is less than the measured HRF.
Holinski, B J; Mazurek, K; Everaert, D G; Mushahwar, V K; Stein, R B
Restoring Stepping After Spinal Cord Injury Using Novel Electrical Stimulation and Feedback Control Strategies Inproceedings
In: Mandl, T; Martinek, J; Bijak, M; Lanmueller, H; Mayr, W; Pichler, M (Ed.): pp. 066, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria, Imperial Riding School, Vienna, Austria, 2010, ISBN: 978-3-900928-09-4.
Abstract | Links | BibTeX | Tags: Lower Extremities, Lower Extremity, SCI
@inproceedings{IFESS2010_066,
title = {Restoring Stepping After Spinal Cord Injury Using Novel Electrical Stimulation and Feedback Control Strategies},
author = {B J Holinski and K Mazurek and D G Everaert and V K Mushahwar and R B Stein},
editor = {T Mandl and J Martinek and M Bijak and H Lanmueller and W Mayr and M Pichler},
url = {https://ifess.org/files/proceedings/IFESS2010/IFESS2010.pdf},
isbn = {978-3-900928-09-4},
year = {2010},
date = {2010-09-01},
pages = {066},
publisher = {Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna Medical School, AKH 4L, Waehringer Guertel 18-20, A-1090 Vienna, Austria},
address = {Imperial Riding School, Vienna, Austria},
abstract = {The overall objective of this project is to develop a feedback-driven intraspinal microstimulation (ISMS) system. We hypothesize that sensory feedback will enhance the functionality of stepping by reducing muscle fatigue and adapting to external perturbations. In the current study, the controller was tested with intramuscular stimulation and external sensors (force plates, gyroscopes, and accelerometers). The walking cycle was divided into 4 states that transitioned with external sensory feedback within a preset range of times. Terminations in the swing phase were best served by accelerometer feedback, while gyroscopes were used to terminate the stance phase. Anesthetized cats were partially supported in a sling and bi-laterally stepped overground on a 4-m instrumented walkway. The walkway had variable friction to perturb the controller. In five cats across 7 experimental sessions, the controller (without feedback) produced an average step length of 24.9 textpm 8.4 (normalized to foot segment length). Steps were shortened (preventing backward slipping) with the addition of sensory feedback to an average length of 21.8 textpm 7.5. Mean peak ground reaction force on each limb also increased from 15.9 textpm 7 % to 18.0 textpm 4.5 % of body weight with the feedback enabled. The step period was programmed for 1.5 sec. The addition of feedback adapted the average step duration to 1.27 textpm 0.25 sec in response to the varying conditions of the walkway. Eventually, this research can be translated into a compact and fully implantable walking prosthesis.},
keywords = {Lower Extremities, Lower Extremity, SCI},
pubstate = {published},
tppubtype = {inproceedings}
}
The overall objective of this project is to develop a feedback-driven intraspinal microstimulation (ISMS) system. We hypothesize that sensory feedback will enhance the functionality of stepping by reducing muscle fatigue and adapting to external perturbations. In the current study, the controller was tested with intramuscular stimulation and external sensors (force plates, gyroscopes, and accelerometers). The walking cycle was divided into 4 states that transitioned with external sensory feedback within a preset range of times. Terminations in the swing phase were best served by accelerometer feedback, while gyroscopes were used to terminate the stance phase. Anesthetized cats were partially supported in a sling and bi-laterally stepped overground on a 4-m instrumented walkway. The walkway had variable friction to perturb the controller. In five cats across 7 experimental sessions, the controller (without feedback) produced an average step length of 24.9 textpm 8.4 (normalized to foot segment length). Steps were shortened (preventing backward slipping) with the addition of sensory feedback to an average length of 21.8 textpm 7.5. Mean peak ground reaction force on each limb also increased from 15.9 textpm 7 % to 18.0 textpm 4.5 % of body weight with the feedback enabled. The step period was programmed for 1.5 sec. The addition of feedback adapted the average step duration to 1.27 textpm 0.25 sec in response to the varying conditions of the walkway. Eventually, this research can be translated into a compact and fully implantable walking prosthesis.