TPress
1.
Trinler, U.; Heitzmann, D. W. W.; Hitzeroth, S.; Alimusaj, M.; Rehg, M.; Hogan, A.
In: Prosthet. Orthot. Int., Bd. 47, Nr. 1, S. 94–100, 2023, ISSN: 0309-3646.
Abstract | Links | Schlagwörter: adult, amputation, article, biomechanics, carbon fiber, clinical article, cohort analysis, ComfyStep, female, foot prosthesis, ground reaction force, human, kinematics, kinetics, knee function, L.A.S.A.R. Posture device, male, medical device, post hoc analysis, prospective study, range of motion, statistical analysis, three dimensional printing, transtibial amputation
@article{Trinler2023,
title = {Biomechanical comparison of a 3D-printed prosthetic foot with conventional feet in people with transtibial amputation: A prospective cohort study},
author = {U. Trinler and D. W. W. Heitzmann and S. Hitzeroth and M. Alimusaj and M. Rehg and A. Hogan},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2022874959&from=export},
doi = {10.1097/PXR.0000000000000180},
issn = {0309-3646},
year = {2023},
date = {2023-08-01},
journal = {Prosthet. Orthot. Int.},
volume = {47},
number = {1},
pages = {94–100},
publisher = {Ovid Technologies (Wolters Kluwer Health)},
address = {U. Trinler, BG Klinik Ludwigshafen, Ludwig-Guttmann-Str. 13, Ludwigshafen, Germany},
abstract = {Introduction: The method of 3D printing is increasingly gaining utilization in clinical applications and may support prosthetic fitting. The aim was to compare biomechanical outcomes of people with a transtibial amputation using a novel, individualizable, 3D-printed prosthetic foot (ComfyStep, Mecuris) with two conventional, widely used prosthetic feet during level ground walking using a 3D motion analysis system. Methods: Ten individuals with an unilateral transtibial amputation were fitted with 3 prosthetic feet (ComfyStep, Assure/Össur, DynamicMotion/Ottobock) using their current, well-fitting socket. They had at least 1 week of familiarization for each foot before gait analyses were conducted. Kinematics and kinetics as well as roll over shape (ROS) length and radius were calculated and compared between feet. Results: The sound side gait parameters of the participants were comparable when using different feet. However, there were differences on the affected side. The statistical analysis revealed that the 3D-printed foot differed significantly compared with the conventional feet in the following aspects: reduced range of motion, increased plantar flexion moment, reduced plantar flexion power, larger ROS radius, less favorable energy ratio, and higher overall stiffness. Conclusion: In principle, 3D-printed feet have advantages over conventional “off the shelf” feet, as their biomechanical characteristics could be adjusted more in detail according to the patient needs. Although, differences between conventional feet and the ComfyStep were shown. Whether these differences have a negative clinically relevant effect remains unclear. However, results suggest that commercially available 3D-printed feet should incorporate systematically better adjustments, for example, for stiffness, to enhance prosthetic performance.},
keywords = {adult, amputation, article, biomechanics, carbon fiber, clinical article, cohort analysis, ComfyStep, female, foot prosthesis, ground reaction force, human, kinematics, kinetics, knee function, L.A.S.A.R. Posture device, male, medical device, post hoc analysis, prospective study, range of motion, statistical analysis, three dimensional printing, transtibial amputation},
pubstate = {published},
tppubtype = {article}
}
Introduction: The method of 3D printing is increasingly gaining utilization in clinical applications and may support prosthetic fitting. The aim was to compare biomechanical outcomes of people with a transtibial amputation using a novel, individualizable, 3D-printed prosthetic foot (ComfyStep, Mecuris) with two conventional, widely used prosthetic feet during level ground walking using a 3D motion analysis system. Methods: Ten individuals with an unilateral transtibial amputation were fitted with 3 prosthetic feet (ComfyStep, Assure/Össur, DynamicMotion/Ottobock) using their current, well-fitting socket. They had at least 1 week of familiarization for each foot before gait analyses were conducted. Kinematics and kinetics as well as roll over shape (ROS) length and radius were calculated and compared between feet. Results: The sound side gait parameters of the participants were comparable when using different feet. However, there were differences on the affected side. The statistical analysis revealed that the 3D-printed foot differed significantly compared with the conventional feet in the following aspects: reduced range of motion, increased plantar flexion moment, reduced plantar flexion power, larger ROS radius, less favorable energy ratio, and higher overall stiffness. Conclusion: In principle, 3D-printed feet have advantages over conventional “off the shelf” feet, as their biomechanical characteristics could be adjusted more in detail according to the patient needs. Although, differences between conventional feet and the ComfyStep were shown. Whether these differences have a negative clinically relevant effect remains unclear. However, results suggest that commercially available 3D-printed feet should incorporate systematically better adjustments, for example, for stiffness, to enhance prosthetic performance.
2.
Köhler, T. M.; Blumentritt, S.; Braatz, F.; Bellmann, M.
In: Gait Posture, Bd. 89, S. 169–177, 2021, ISSN: 0966-6362.
Abstract | Links | Schlagwörter: above knee amputation, adduction, adult, article, biomechanics, camera, clinical article, controlled study, female, femoral knee prosthesis, gait, Genium, ground reaction force, human, male, microprocessor, motion analysis system, pelvis, prosthetic alignment, step length, transfemoral amputation, transfemoral prosthetic socket, Triton, trunk, tyloxapol, Vicon Bonita, walking, walking speed
@article{Koehler2021,
title = {The impact of transfemoral socket adduction on pelvic and trunk stabilization during level walking - A biomechanical study},
author = {T. M. Köhler and S. Blumentritt and F. Braatz and M. Bellmann},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2013710687&from=export},
doi = {10.1016/j.gaitpost.2021.06.024},
issn = {0966-6362},
year = {2021},
date = {2021-09-01},
journal = {Gait Posture},
volume = {89},
pages = {169–177},
publisher = {Elsevier BV},
address = {T.M. Köhler, Ottobock SE & Co. KGaA, Hermann-Rein-Straße 2a, Göttingen, Germany},
abstract = {Background: It is common practice to align transfemoral prosthetic sockets in adduction, due to the physiologic, adducted femoral alignment in unimpaired legs. An adducted femoral and socket alignment helps tightening hip abductors to stabilize the pelvis and reduce pelvic and trunk related compensatory movements. Research question: How do different socket adduction conditions (SAC) of transfemoral sockets affect pelvic and trunk stabilization during level ground walking in the frontal plane? Methods: Seven persons with transfemoral amputation with medium residual limb length participated in this study. The prosthetic alignment in the sagittal plane was performed according to established recommendations. SAC varied (0°, 3°, 6°, 9°). Kinematic and kinetic parameters were recorded in a gait laboratory with a 12-camera optoelectronic system and two piezoelectric force plates embedded in a 12-m walkway. The measurements were performed during level ground walking with self-selected comfortable gait speed. Results: In the frontal plane, nearly all investigated kinematic and kinetic parameters showed a strong correlation with the SAC. The pelvis was raised on the contralateral side throughout the gait cycle with increasing SAC. During the prosthetic side stance phase, the mean shoulder obliquity and mean lateral trunk lean to the prosthetic side tended to be reduced with increased SAC. Prosthetic side hip abduction moment decreased with increasing SAC. Significance: The results confirm that transfemoral SAC contributes to pelvic stabilization and reduced compensatory movements of the pelvis and trunk. Transfemoral SAC of 6 ± 1° for bench alignment seems adequate for amputees with medium residual limb length. However, the optimum value for the individual patient may differ slightly.},
keywords = {above knee amputation, adduction, adult, article, biomechanics, camera, clinical article, controlled study, female, femoral knee prosthesis, gait, Genium, ground reaction force, human, male, microprocessor, motion analysis system, pelvis, prosthetic alignment, step length, transfemoral amputation, transfemoral prosthetic socket, Triton, trunk, tyloxapol, Vicon Bonita, walking, walking speed},
pubstate = {published},
tppubtype = {article}
}
Background: It is common practice to align transfemoral prosthetic sockets in adduction, due to the physiologic, adducted femoral alignment in unimpaired legs. An adducted femoral and socket alignment helps tightening hip abductors to stabilize the pelvis and reduce pelvic and trunk related compensatory movements. Research question: How do different socket adduction conditions (SAC) of transfemoral sockets affect pelvic and trunk stabilization during level ground walking in the frontal plane? Methods: Seven persons with transfemoral amputation with medium residual limb length participated in this study. The prosthetic alignment in the sagittal plane was performed according to established recommendations. SAC varied (0°, 3°, 6°, 9°). Kinematic and kinetic parameters were recorded in a gait laboratory with a 12-camera optoelectronic system and two piezoelectric force plates embedded in a 12-m walkway. The measurements were performed during level ground walking with self-selected comfortable gait speed. Results: In the frontal plane, nearly all investigated kinematic and kinetic parameters showed a strong correlation with the SAC. The pelvis was raised on the contralateral side throughout the gait cycle with increasing SAC. During the prosthetic side stance phase, the mean shoulder obliquity and mean lateral trunk lean to the prosthetic side tended to be reduced with increased SAC. Prosthetic side hip abduction moment decreased with increasing SAC. Significance: The results confirm that transfemoral SAC contributes to pelvic stabilization and reduced compensatory movements of the pelvis and trunk. Transfemoral SAC of 6 ± 1° for bench alignment seems adequate for amputees with medium residual limb length. However, the optimum value for the individual patient may differ slightly.
3.
Waterval, N. F. J.; Brehm, M. -A.; Harlaar, J.; Nollet, F.
In: J. NeuroEng. Rehabil., Bd. 18, Nr. 1, 2021, ISSN: 1743-0003.
Abstract | Links | Schlagwörter: adult, ankle foot orthosis, article, body weight, Carbon Ankle7, clinical effectiveness, correlational study, dorsal leaf spring ankle foot orthosis, energy cost, female, human, male, middle aged, muscle strength, muscle weakness, range of motion, risk factor, triceps surae muscle, walking speed
@article{Waterval2021,
title = {Individual stiffness optimization of dorsal leaf spring ankle-foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations},
author = {N. F. J. Waterval and M. -A. Brehm and J. Harlaar and F. Nollet},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2012344314&from=export},
doi = {10.1186/s12984-021-00890-8},
issn = {1743-0003},
year = {2021},
date = {2021-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {18},
number = {1},
address = {N.F.J. Waterval, Rehabilitation Medicine, Amsterdam Movement Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, Netherlands},
abstract = {Background: In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle-foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods: Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results: In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s},
keywords = {adult, ankle foot orthosis, article, body weight, Carbon Ankle7, clinical effectiveness, correlational study, dorsal leaf spring ankle foot orthosis, energy cost, female, human, male, middle aged, muscle strength, muscle weakness, range of motion, risk factor, triceps surae muscle, walking speed},
pubstate = {published},
tppubtype = {article}
}
Background: In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle-foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods: Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results: In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s
4.
Yazdani, M.; Hajiaghaei, B.; Saeedi, H.; Kamali, M.; Yousefi, M.
In: Curr. Orthop. Pract., Bd. 32, Nr. 5, S. 505–511, 2021, ISSN: 1940-7041.
Abstract | Links | Schlagwörter: adult, amputee, article, camera, case study, clinical article, comparative study, compression release stabilization, data analysis software, evaluation study, female, femoral shaft, foot prosthesis, gait, gluteus muscle, human, information processing device, IRCT20181021041400N1, ischial tuberosity, kinematics, knee prosthesis, leather belt wrap, limb amputation, male, MATLAB, medical device, middle aged, motion analysis system, orthopedic cast, orthopedic surgical equipment, Ottobock 3R20, pilot study, prosthesis design, quadrilateral socket, solid ankle cushioned heel foot, statistical model, step length, step time, step width, stride length, stride time, symmetry index, transfemoral socket, walking, walking speed, weight training, Wilcoxon signed ranks test
@article{Yazdani2021,
title = {Does the socket design affect symmetry and spatiotemporal gait parameters? A case series of two transfemoral amputees},
author = {M. Yazdani and B. Hajiaghaei and H. Saeedi and M. Kamali and M. Yousefi},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L635549609&from=export},
doi = {10.1097/bco.0000000000001022},
issn = {1940-7041},
year = {2021},
date = {2021-01-01},
journal = {Curr. Orthop. Pract.},
volume = {32},
number = {5},
pages = {505–511},
address = {B. Hajiaghaei, Department of Orthotics and Prosthetics, School of Rehabilitation Sciences, Iran University of Medical Sciences, Nezam Ave, Tehran, Iran},
abstract = {Background: Socket design is thought to improve gait performance and symmetry as the other components of the prosthesis do. This study focused on the comparison of two different sockets in transfemoral amputee patients to evaluate the influence of the socket designs on gait symmetry and various spatiotemporal gait parameters. Methods: Two transfemoral amputees participated in this case series study. They were asked to walk with the quadrilateral and the new modified sockets along a 10-meter walkway. The marker-based motion capture system recorded the spatiotemporal gait data during all walking trials. Kinematic data were compared between the two test conditions using the Wilcoxon signed-rank test and Symmetry Index. Results: The new socket increased velocity and cadence and reduced step width in both amputees, compared with the quadrilateral sockets. However, a good symmetry was observed in step length, stride length, step time, and stride time within two limbs by both sockets (SI ≤10). Conclusions: The design of sockets in this study had no observed effect on gait symmetry; however, the new socket increased velocity and cadence and reduced width step in both patients compared with the quadrilateral socket. Level of Evidence: Level IV.},
keywords = {adult, amputee, article, camera, case study, clinical article, comparative study, compression release stabilization, data analysis software, evaluation study, female, femoral shaft, foot prosthesis, gait, gluteus muscle, human, information processing device, IRCT20181021041400N1, ischial tuberosity, kinematics, knee prosthesis, leather belt wrap, limb amputation, male, MATLAB, medical device, middle aged, motion analysis system, orthopedic cast, orthopedic surgical equipment, Ottobock 3R20, pilot study, prosthesis design, quadrilateral socket, solid ankle cushioned heel foot, statistical model, step length, step time, step width, stride length, stride time, symmetry index, transfemoral socket, walking, walking speed, weight training, Wilcoxon signed ranks test},
pubstate = {published},
tppubtype = {article}
}
Background: Socket design is thought to improve gait performance and symmetry as the other components of the prosthesis do. This study focused on the comparison of two different sockets in transfemoral amputee patients to evaluate the influence of the socket designs on gait symmetry and various spatiotemporal gait parameters. Methods: Two transfemoral amputees participated in this case series study. They were asked to walk with the quadrilateral and the new modified sockets along a 10-meter walkway. The marker-based motion capture system recorded the spatiotemporal gait data during all walking trials. Kinematic data were compared between the two test conditions using the Wilcoxon signed-rank test and Symmetry Index. Results: The new socket increased velocity and cadence and reduced step width in both amputees, compared with the quadrilateral sockets. However, a good symmetry was observed in step length, stride length, step time, and stride time within two limbs by both sockets (SI ≤10). Conclusions: The design of sockets in this study had no observed effect on gait symmetry; however, the new socket increased velocity and cadence and reduced width step in both patients compared with the quadrilateral socket. Level of Evidence: Level IV.
5.
Schmalz, T.; Schändlinger, J.; Schuler, M.; Bornmann, J.; Schirrmeister, B.; Kannenberg, A.; Ernst, M.
Biomechanical and metabolic effectiveness of an industrial exoskeleton for overhead work Artikel
In: Int. J. Environ. Res. Public Health, Bd. 16, Nr. 23, 2019, ISSN: 1661-7827.
Abstract | Links | Schlagwörter: adult, article, biceps brachii muscle, biomechanics, body position, controlled study, deltoid muscle, electromyograph, electromyography, exoskeleton (rehabilitation), female, heart rate, human, human experiment, kinematics, latissimus dorsi muscle, male, metabolic parameters, normal human, oblique abdominal muscle, oxygen consumption, serratus muscle, skeletal muscle, trapezius muscle
@article{Schmalz2019,
title = {Biomechanical and metabolic effectiveness of an industrial exoskeleton for overhead work},
author = {T. Schmalz and J. Schändlinger and M. Schuler and J. Bornmann and B. Schirrmeister and A. Kannenberg and M. Ernst},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2003259386&from=export},
doi = {10.3390/ijerph16234792},
issn = {1661-7827},
year = {2019},
date = {2019-01-01},
journal = {Int. J. Environ. Res. Public Health},
volume = {16},
number = {23},
address = {T. Schmalz, Clinical Research & Services/Biomechanics, Otto Bock SE & Co. KGaA, Göttingen, Germany},
abstract = {Overhead work activities can lead to shoulder pain and serious musculoskeletal disorders (WMSD), such as rotator cuff injury and degeneration. Recently developed exoskeletons show promising results in supporting workers in such activities. In this study, a novel exoskeleton was investigated for two different overhead tasks with twelve participants. To investigate the effects of the device, electromyographic (EMG) signals of different shoulder and adjacent muscles as well as kinematic and metabolic parameters were analyzed with and without the exoskeleton. The mean EMG amplitude of all evaluated muscles was significantly reduced when the exoskeleton was used for the overhead tasks. This was accompanied by a reduction in both heart rate and oxygen rate. The kinematic analysis revealed small changes in the joint positions during the tasks. This study demonstrated the biomechanical and metabolic benefits of an exoskeleton designed to support overhead work activities. The results suggest improved physiological conditions and an unloading effect on the shoulder joint and muscles which are promising indicators that the exoskeleton may be a good solution to reduce shoulder WMSD among workers who carry out overhead tasks on a regular basis.},
keywords = {adult, article, biceps brachii muscle, biomechanics, body position, controlled study, deltoid muscle, electromyograph, electromyography, exoskeleton (rehabilitation), female, heart rate, human, human experiment, kinematics, latissimus dorsi muscle, male, metabolic parameters, normal human, oblique abdominal muscle, oxygen consumption, serratus muscle, skeletal muscle, trapezius muscle},
pubstate = {published},
tppubtype = {article}
}
Overhead work activities can lead to shoulder pain and serious musculoskeletal disorders (WMSD), such as rotator cuff injury and degeneration. Recently developed exoskeletons show promising results in supporting workers in such activities. In this study, a novel exoskeleton was investigated for two different overhead tasks with twelve participants. To investigate the effects of the device, electromyographic (EMG) signals of different shoulder and adjacent muscles as well as kinematic and metabolic parameters were analyzed with and without the exoskeleton. The mean EMG amplitude of all evaluated muscles was significantly reduced when the exoskeleton was used for the overhead tasks. This was accompanied by a reduction in both heart rate and oxygen rate. The kinematic analysis revealed small changes in the joint positions during the tasks. This study demonstrated the biomechanical and metabolic benefits of an exoskeleton designed to support overhead work activities. The results suggest improved physiological conditions and an unloading effect on the shoulder joint and muscles which are promising indicators that the exoskeleton may be a good solution to reduce shoulder WMSD among workers who carry out overhead tasks on a regular basis.
2023
Trinler, U.; Heitzmann, D. W. W.; Hitzeroth, S.; Alimusaj, M.; Rehg, M.; Hogan, A.
In: Prosthet. Orthot. Int., Bd. 47, Nr. 1, S. 94–100, 2023, ISSN: 0309-3646.
Abstract | Links | Schlagwörter: adult, amputation, article, biomechanics, carbon fiber, clinical article, cohort analysis, ComfyStep, female, foot prosthesis, ground reaction force, human, kinematics, kinetics, knee function, L.A.S.A.R. Posture device, male, medical device, post hoc analysis, prospective study, range of motion, statistical analysis, three dimensional printing, transtibial amputation
@article{Trinler2023,
title = {Biomechanical comparison of a 3D-printed prosthetic foot with conventional feet in people with transtibial amputation: A prospective cohort study},
author = {U. Trinler and D. W. W. Heitzmann and S. Hitzeroth and M. Alimusaj and M. Rehg and A. Hogan},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2022874959&from=export},
doi = {10.1097/PXR.0000000000000180},
issn = {0309-3646},
year = {2023},
date = {2023-08-01},
journal = {Prosthet. Orthot. Int.},
volume = {47},
number = {1},
pages = {94–100},
publisher = {Ovid Technologies (Wolters Kluwer Health)},
address = {U. Trinler, BG Klinik Ludwigshafen, Ludwig-Guttmann-Str. 13, Ludwigshafen, Germany},
abstract = {Introduction: The method of 3D printing is increasingly gaining utilization in clinical applications and may support prosthetic fitting. The aim was to compare biomechanical outcomes of people with a transtibial amputation using a novel, individualizable, 3D-printed prosthetic foot (ComfyStep, Mecuris) with two conventional, widely used prosthetic feet during level ground walking using a 3D motion analysis system. Methods: Ten individuals with an unilateral transtibial amputation were fitted with 3 prosthetic feet (ComfyStep, Assure/Össur, DynamicMotion/Ottobock) using their current, well-fitting socket. They had at least 1 week of familiarization for each foot before gait analyses were conducted. Kinematics and kinetics as well as roll over shape (ROS) length and radius were calculated and compared between feet. Results: The sound side gait parameters of the participants were comparable when using different feet. However, there were differences on the affected side. The statistical analysis revealed that the 3D-printed foot differed significantly compared with the conventional feet in the following aspects: reduced range of motion, increased plantar flexion moment, reduced plantar flexion power, larger ROS radius, less favorable energy ratio, and higher overall stiffness. Conclusion: In principle, 3D-printed feet have advantages over conventional “off the shelf” feet, as their biomechanical characteristics could be adjusted more in detail according to the patient needs. Although, differences between conventional feet and the ComfyStep were shown. Whether these differences have a negative clinically relevant effect remains unclear. However, results suggest that commercially available 3D-printed feet should incorporate systematically better adjustments, for example, for stiffness, to enhance prosthetic performance.},
keywords = {adult, amputation, article, biomechanics, carbon fiber, clinical article, cohort analysis, ComfyStep, female, foot prosthesis, ground reaction force, human, kinematics, kinetics, knee function, L.A.S.A.R. Posture device, male, medical device, post hoc analysis, prospective study, range of motion, statistical analysis, three dimensional printing, transtibial amputation},
pubstate = {published},
tppubtype = {article}
}
Introduction: The method of 3D printing is increasingly gaining utilization in clinical applications and may support prosthetic fitting. The aim was to compare biomechanical outcomes of people with a transtibial amputation using a novel, individualizable, 3D-printed prosthetic foot (ComfyStep, Mecuris) with two conventional, widely used prosthetic feet during level ground walking using a 3D motion analysis system. Methods: Ten individuals with an unilateral transtibial amputation were fitted with 3 prosthetic feet (ComfyStep, Assure/Össur, DynamicMotion/Ottobock) using their current, well-fitting socket. They had at least 1 week of familiarization for each foot before gait analyses were conducted. Kinematics and kinetics as well as roll over shape (ROS) length and radius were calculated and compared between feet. Results: The sound side gait parameters of the participants were comparable when using different feet. However, there were differences on the affected side. The statistical analysis revealed that the 3D-printed foot differed significantly compared with the conventional feet in the following aspects: reduced range of motion, increased plantar flexion moment, reduced plantar flexion power, larger ROS radius, less favorable energy ratio, and higher overall stiffness. Conclusion: In principle, 3D-printed feet have advantages over conventional “off the shelf” feet, as their biomechanical characteristics could be adjusted more in detail according to the patient needs. Although, differences between conventional feet and the ComfyStep were shown. Whether these differences have a negative clinically relevant effect remains unclear. However, results suggest that commercially available 3D-printed feet should incorporate systematically better adjustments, for example, for stiffness, to enhance prosthetic performance.
2021
Köhler, T. M.; Blumentritt, S.; Braatz, F.; Bellmann, M.
In: Gait Posture, Bd. 89, S. 169–177, 2021, ISSN: 0966-6362.
Abstract | Links | Schlagwörter: above knee amputation, adduction, adult, article, biomechanics, camera, clinical article, controlled study, female, femoral knee prosthesis, gait, Genium, ground reaction force, human, male, microprocessor, motion analysis system, pelvis, prosthetic alignment, step length, transfemoral amputation, transfemoral prosthetic socket, Triton, trunk, tyloxapol, Vicon Bonita, walking, walking speed
@article{Koehler2021,
title = {The impact of transfemoral socket adduction on pelvic and trunk stabilization during level walking - A biomechanical study},
author = {T. M. Köhler and S. Blumentritt and F. Braatz and M. Bellmann},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2013710687&from=export},
doi = {10.1016/j.gaitpost.2021.06.024},
issn = {0966-6362},
year = {2021},
date = {2021-09-01},
journal = {Gait Posture},
volume = {89},
pages = {169–177},
publisher = {Elsevier BV},
address = {T.M. Köhler, Ottobock SE & Co. KGaA, Hermann-Rein-Straße 2a, Göttingen, Germany},
abstract = {Background: It is common practice to align transfemoral prosthetic sockets in adduction, due to the physiologic, adducted femoral alignment in unimpaired legs. An adducted femoral and socket alignment helps tightening hip abductors to stabilize the pelvis and reduce pelvic and trunk related compensatory movements. Research question: How do different socket adduction conditions (SAC) of transfemoral sockets affect pelvic and trunk stabilization during level ground walking in the frontal plane? Methods: Seven persons with transfemoral amputation with medium residual limb length participated in this study. The prosthetic alignment in the sagittal plane was performed according to established recommendations. SAC varied (0°, 3°, 6°, 9°). Kinematic and kinetic parameters were recorded in a gait laboratory with a 12-camera optoelectronic system and two piezoelectric force plates embedded in a 12-m walkway. The measurements were performed during level ground walking with self-selected comfortable gait speed. Results: In the frontal plane, nearly all investigated kinematic and kinetic parameters showed a strong correlation with the SAC. The pelvis was raised on the contralateral side throughout the gait cycle with increasing SAC. During the prosthetic side stance phase, the mean shoulder obliquity and mean lateral trunk lean to the prosthetic side tended to be reduced with increased SAC. Prosthetic side hip abduction moment decreased with increasing SAC. Significance: The results confirm that transfemoral SAC contributes to pelvic stabilization and reduced compensatory movements of the pelvis and trunk. Transfemoral SAC of 6 ± 1° for bench alignment seems adequate for amputees with medium residual limb length. However, the optimum value for the individual patient may differ slightly.},
keywords = {above knee amputation, adduction, adult, article, biomechanics, camera, clinical article, controlled study, female, femoral knee prosthesis, gait, Genium, ground reaction force, human, male, microprocessor, motion analysis system, pelvis, prosthetic alignment, step length, transfemoral amputation, transfemoral prosthetic socket, Triton, trunk, tyloxapol, Vicon Bonita, walking, walking speed},
pubstate = {published},
tppubtype = {article}
}
Background: It is common practice to align transfemoral prosthetic sockets in adduction, due to the physiologic, adducted femoral alignment in unimpaired legs. An adducted femoral and socket alignment helps tightening hip abductors to stabilize the pelvis and reduce pelvic and trunk related compensatory movements. Research question: How do different socket adduction conditions (SAC) of transfemoral sockets affect pelvic and trunk stabilization during level ground walking in the frontal plane? Methods: Seven persons with transfemoral amputation with medium residual limb length participated in this study. The prosthetic alignment in the sagittal plane was performed according to established recommendations. SAC varied (0°, 3°, 6°, 9°). Kinematic and kinetic parameters were recorded in a gait laboratory with a 12-camera optoelectronic system and two piezoelectric force plates embedded in a 12-m walkway. The measurements were performed during level ground walking with self-selected comfortable gait speed. Results: In the frontal plane, nearly all investigated kinematic and kinetic parameters showed a strong correlation with the SAC. The pelvis was raised on the contralateral side throughout the gait cycle with increasing SAC. During the prosthetic side stance phase, the mean shoulder obliquity and mean lateral trunk lean to the prosthetic side tended to be reduced with increased SAC. Prosthetic side hip abduction moment decreased with increasing SAC. Significance: The results confirm that transfemoral SAC contributes to pelvic stabilization and reduced compensatory movements of the pelvis and trunk. Transfemoral SAC of 6 ± 1° for bench alignment seems adequate for amputees with medium residual limb length. However, the optimum value for the individual patient may differ slightly.
Waterval, N. F. J.; Brehm, M. -A.; Harlaar, J.; Nollet, F.
In: J. NeuroEng. Rehabil., Bd. 18, Nr. 1, 2021, ISSN: 1743-0003.
Abstract | Links | Schlagwörter: adult, ankle foot orthosis, article, body weight, Carbon Ankle7, clinical effectiveness, correlational study, dorsal leaf spring ankle foot orthosis, energy cost, female, human, male, middle aged, muscle strength, muscle weakness, range of motion, risk factor, triceps surae muscle, walking speed
@article{Waterval2021,
title = {Individual stiffness optimization of dorsal leaf spring ankle-foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations},
author = {N. F. J. Waterval and M. -A. Brehm and J. Harlaar and F. Nollet},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2012344314&from=export},
doi = {10.1186/s12984-021-00890-8},
issn = {1743-0003},
year = {2021},
date = {2021-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {18},
number = {1},
address = {N.F.J. Waterval, Rehabilitation Medicine, Amsterdam Movement Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, Netherlands},
abstract = {Background: In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle-foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods: Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results: In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s},
keywords = {adult, ankle foot orthosis, article, body weight, Carbon Ankle7, clinical effectiveness, correlational study, dorsal leaf spring ankle foot orthosis, energy cost, female, human, male, middle aged, muscle strength, muscle weakness, range of motion, risk factor, triceps surae muscle, walking speed},
pubstate = {published},
tppubtype = {article}
}
Background: In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle-foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods: Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results: In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s
Yazdani, M.; Hajiaghaei, B.; Saeedi, H.; Kamali, M.; Yousefi, M.
In: Curr. Orthop. Pract., Bd. 32, Nr. 5, S. 505–511, 2021, ISSN: 1940-7041.
Abstract | Links | Schlagwörter: adult, amputee, article, camera, case study, clinical article, comparative study, compression release stabilization, data analysis software, evaluation study, female, femoral shaft, foot prosthesis, gait, gluteus muscle, human, information processing device, IRCT20181021041400N1, ischial tuberosity, kinematics, knee prosthesis, leather belt wrap, limb amputation, male, MATLAB, medical device, middle aged, motion analysis system, orthopedic cast, orthopedic surgical equipment, Ottobock 3R20, pilot study, prosthesis design, quadrilateral socket, solid ankle cushioned heel foot, statistical model, step length, step time, step width, stride length, stride time, symmetry index, transfemoral socket, walking, walking speed, weight training, Wilcoxon signed ranks test
@article{Yazdani2021,
title = {Does the socket design affect symmetry and spatiotemporal gait parameters? A case series of two transfemoral amputees},
author = {M. Yazdani and B. Hajiaghaei and H. Saeedi and M. Kamali and M. Yousefi},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L635549609&from=export},
doi = {10.1097/bco.0000000000001022},
issn = {1940-7041},
year = {2021},
date = {2021-01-01},
journal = {Curr. Orthop. Pract.},
volume = {32},
number = {5},
pages = {505–511},
address = {B. Hajiaghaei, Department of Orthotics and Prosthetics, School of Rehabilitation Sciences, Iran University of Medical Sciences, Nezam Ave, Tehran, Iran},
abstract = {Background: Socket design is thought to improve gait performance and symmetry as the other components of the prosthesis do. This study focused on the comparison of two different sockets in transfemoral amputee patients to evaluate the influence of the socket designs on gait symmetry and various spatiotemporal gait parameters. Methods: Two transfemoral amputees participated in this case series study. They were asked to walk with the quadrilateral and the new modified sockets along a 10-meter walkway. The marker-based motion capture system recorded the spatiotemporal gait data during all walking trials. Kinematic data were compared between the two test conditions using the Wilcoxon signed-rank test and Symmetry Index. Results: The new socket increased velocity and cadence and reduced step width in both amputees, compared with the quadrilateral sockets. However, a good symmetry was observed in step length, stride length, step time, and stride time within two limbs by both sockets (SI ≤10). Conclusions: The design of sockets in this study had no observed effect on gait symmetry; however, the new socket increased velocity and cadence and reduced width step in both patients compared with the quadrilateral socket. Level of Evidence: Level IV.},
keywords = {adult, amputee, article, camera, case study, clinical article, comparative study, compression release stabilization, data analysis software, evaluation study, female, femoral shaft, foot prosthesis, gait, gluteus muscle, human, information processing device, IRCT20181021041400N1, ischial tuberosity, kinematics, knee prosthesis, leather belt wrap, limb amputation, male, MATLAB, medical device, middle aged, motion analysis system, orthopedic cast, orthopedic surgical equipment, Ottobock 3R20, pilot study, prosthesis design, quadrilateral socket, solid ankle cushioned heel foot, statistical model, step length, step time, step width, stride length, stride time, symmetry index, transfemoral socket, walking, walking speed, weight training, Wilcoxon signed ranks test},
pubstate = {published},
tppubtype = {article}
}
Background: Socket design is thought to improve gait performance and symmetry as the other components of the prosthesis do. This study focused on the comparison of two different sockets in transfemoral amputee patients to evaluate the influence of the socket designs on gait symmetry and various spatiotemporal gait parameters. Methods: Two transfemoral amputees participated in this case series study. They were asked to walk with the quadrilateral and the new modified sockets along a 10-meter walkway. The marker-based motion capture system recorded the spatiotemporal gait data during all walking trials. Kinematic data were compared between the two test conditions using the Wilcoxon signed-rank test and Symmetry Index. Results: The new socket increased velocity and cadence and reduced step width in both amputees, compared with the quadrilateral sockets. However, a good symmetry was observed in step length, stride length, step time, and stride time within two limbs by both sockets (SI ≤10). Conclusions: The design of sockets in this study had no observed effect on gait symmetry; however, the new socket increased velocity and cadence and reduced width step in both patients compared with the quadrilateral socket. Level of Evidence: Level IV.
2019
Schmalz, T.; Schändlinger, J.; Schuler, M.; Bornmann, J.; Schirrmeister, B.; Kannenberg, A.; Ernst, M.
Biomechanical and metabolic effectiveness of an industrial exoskeleton for overhead work Artikel
In: Int. J. Environ. Res. Public Health, Bd. 16, Nr. 23, 2019, ISSN: 1661-7827.
Abstract | Links | Schlagwörter: adult, article, biceps brachii muscle, biomechanics, body position, controlled study, deltoid muscle, electromyograph, electromyography, exoskeleton (rehabilitation), female, heart rate, human, human experiment, kinematics, latissimus dorsi muscle, male, metabolic parameters, normal human, oblique abdominal muscle, oxygen consumption, serratus muscle, skeletal muscle, trapezius muscle
@article{Schmalz2019,
title = {Biomechanical and metabolic effectiveness of an industrial exoskeleton for overhead work},
author = {T. Schmalz and J. Schändlinger and M. Schuler and J. Bornmann and B. Schirrmeister and A. Kannenberg and M. Ernst},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2003259386&from=export},
doi = {10.3390/ijerph16234792},
issn = {1661-7827},
year = {2019},
date = {2019-01-01},
journal = {Int. J. Environ. Res. Public Health},
volume = {16},
number = {23},
address = {T. Schmalz, Clinical Research & Services/Biomechanics, Otto Bock SE & Co. KGaA, Göttingen, Germany},
abstract = {Overhead work activities can lead to shoulder pain and serious musculoskeletal disorders (WMSD), such as rotator cuff injury and degeneration. Recently developed exoskeletons show promising results in supporting workers in such activities. In this study, a novel exoskeleton was investigated for two different overhead tasks with twelve participants. To investigate the effects of the device, electromyographic (EMG) signals of different shoulder and adjacent muscles as well as kinematic and metabolic parameters were analyzed with and without the exoskeleton. The mean EMG amplitude of all evaluated muscles was significantly reduced when the exoskeleton was used for the overhead tasks. This was accompanied by a reduction in both heart rate and oxygen rate. The kinematic analysis revealed small changes in the joint positions during the tasks. This study demonstrated the biomechanical and metabolic benefits of an exoskeleton designed to support overhead work activities. The results suggest improved physiological conditions and an unloading effect on the shoulder joint and muscles which are promising indicators that the exoskeleton may be a good solution to reduce shoulder WMSD among workers who carry out overhead tasks on a regular basis.},
keywords = {adult, article, biceps brachii muscle, biomechanics, body position, controlled study, deltoid muscle, electromyograph, electromyography, exoskeleton (rehabilitation), female, heart rate, human, human experiment, kinematics, latissimus dorsi muscle, male, metabolic parameters, normal human, oblique abdominal muscle, oxygen consumption, serratus muscle, skeletal muscle, trapezius muscle},
pubstate = {published},
tppubtype = {article}
}
Overhead work activities can lead to shoulder pain and serious musculoskeletal disorders (WMSD), such as rotator cuff injury and degeneration. Recently developed exoskeletons show promising results in supporting workers in such activities. In this study, a novel exoskeleton was investigated for two different overhead tasks with twelve participants. To investigate the effects of the device, electromyographic (EMG) signals of different shoulder and adjacent muscles as well as kinematic and metabolic parameters were analyzed with and without the exoskeleton. The mean EMG amplitude of all evaluated muscles was significantly reduced when the exoskeleton was used for the overhead tasks. This was accompanied by a reduction in both heart rate and oxygen rate. The kinematic analysis revealed small changes in the joint positions during the tasks. This study demonstrated the biomechanical and metabolic benefits of an exoskeleton designed to support overhead work activities. The results suggest improved physiological conditions and an unloading effect on the shoulder joint and muscles which are promising indicators that the exoskeleton may be a good solution to reduce shoulder WMSD among workers who carry out overhead tasks on a regular basis.
2023
Trinler, U.; Heitzmann, D. W. W.; Hitzeroth, S.; Alimusaj, M.; Rehg, M.; Hogan, A.
In: Prosthet. Orthot. Int., Bd. 47, Nr. 1, S. 94–100, 2023, ISSN: 0309-3646.
@article{Trinler2023,
title = {Biomechanical comparison of a 3D-printed prosthetic foot with conventional feet in people with transtibial amputation: A prospective cohort study},
author = {U. Trinler and D. W. W. Heitzmann and S. Hitzeroth and M. Alimusaj and M. Rehg and A. Hogan},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2022874959&from=export},
doi = {10.1097/PXR.0000000000000180},
issn = {0309-3646},
year = {2023},
date = {2023-08-01},
journal = {Prosthet. Orthot. Int.},
volume = {47},
number = {1},
pages = {94–100},
publisher = {Ovid Technologies (Wolters Kluwer Health)},
address = {U. Trinler, BG Klinik Ludwigshafen, Ludwig-Guttmann-Str. 13, Ludwigshafen, Germany},
abstract = {Introduction: The method of 3D printing is increasingly gaining utilization in clinical applications and may support prosthetic fitting. The aim was to compare biomechanical outcomes of people with a transtibial amputation using a novel, individualizable, 3D-printed prosthetic foot (ComfyStep, Mecuris) with two conventional, widely used prosthetic feet during level ground walking using a 3D motion analysis system. Methods: Ten individuals with an unilateral transtibial amputation were fitted with 3 prosthetic feet (ComfyStep, Assure/Össur, DynamicMotion/Ottobock) using their current, well-fitting socket. They had at least 1 week of familiarization for each foot before gait analyses were conducted. Kinematics and kinetics as well as roll over shape (ROS) length and radius were calculated and compared between feet. Results: The sound side gait parameters of the participants were comparable when using different feet. However, there were differences on the affected side. The statistical analysis revealed that the 3D-printed foot differed significantly compared with the conventional feet in the following aspects: reduced range of motion, increased plantar flexion moment, reduced plantar flexion power, larger ROS radius, less favorable energy ratio, and higher overall stiffness. Conclusion: In principle, 3D-printed feet have advantages over conventional “off the shelf” feet, as their biomechanical characteristics could be adjusted more in detail according to the patient needs. Although, differences between conventional feet and the ComfyStep were shown. Whether these differences have a negative clinically relevant effect remains unclear. However, results suggest that commercially available 3D-printed feet should incorporate systematically better adjustments, for example, for stiffness, to enhance prosthetic performance.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Introduction: The method of 3D printing is increasingly gaining utilization in clinical applications and may support prosthetic fitting. The aim was to compare biomechanical outcomes of people with a transtibial amputation using a novel, individualizable, 3D-printed prosthetic foot (ComfyStep, Mecuris) with two conventional, widely used prosthetic feet during level ground walking using a 3D motion analysis system. Methods: Ten individuals with an unilateral transtibial amputation were fitted with 3 prosthetic feet (ComfyStep, Assure/Össur, DynamicMotion/Ottobock) using their current, well-fitting socket. They had at least 1 week of familiarization for each foot before gait analyses were conducted. Kinematics and kinetics as well as roll over shape (ROS) length and radius were calculated and compared between feet. Results: The sound side gait parameters of the participants were comparable when using different feet. However, there were differences on the affected side. The statistical analysis revealed that the 3D-printed foot differed significantly compared with the conventional feet in the following aspects: reduced range of motion, increased plantar flexion moment, reduced plantar flexion power, larger ROS radius, less favorable energy ratio, and higher overall stiffness. Conclusion: In principle, 3D-printed feet have advantages over conventional “off the shelf” feet, as their biomechanical characteristics could be adjusted more in detail according to the patient needs. Although, differences between conventional feet and the ComfyStep were shown. Whether these differences have a negative clinically relevant effect remains unclear. However, results suggest that commercially available 3D-printed feet should incorporate systematically better adjustments, for example, for stiffness, to enhance prosthetic performance.
2021
Köhler, T. M.; Blumentritt, S.; Braatz, F.; Bellmann, M.
In: Gait Posture, Bd. 89, S. 169–177, 2021, ISSN: 0966-6362.
@article{Koehler2021,
title = {The impact of transfemoral socket adduction on pelvic and trunk stabilization during level walking - A biomechanical study},
author = {T. M. Köhler and S. Blumentritt and F. Braatz and M. Bellmann},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2013710687&from=export},
doi = {10.1016/j.gaitpost.2021.06.024},
issn = {0966-6362},
year = {2021},
date = {2021-09-01},
journal = {Gait Posture},
volume = {89},
pages = {169–177},
publisher = {Elsevier BV},
address = {T.M. Köhler, Ottobock SE & Co. KGaA, Hermann-Rein-Straße 2a, Göttingen, Germany},
abstract = {Background: It is common practice to align transfemoral prosthetic sockets in adduction, due to the physiologic, adducted femoral alignment in unimpaired legs. An adducted femoral and socket alignment helps tightening hip abductors to stabilize the pelvis and reduce pelvic and trunk related compensatory movements. Research question: How do different socket adduction conditions (SAC) of transfemoral sockets affect pelvic and trunk stabilization during level ground walking in the frontal plane? Methods: Seven persons with transfemoral amputation with medium residual limb length participated in this study. The prosthetic alignment in the sagittal plane was performed according to established recommendations. SAC varied (0°, 3°, 6°, 9°). Kinematic and kinetic parameters were recorded in a gait laboratory with a 12-camera optoelectronic system and two piezoelectric force plates embedded in a 12-m walkway. The measurements were performed during level ground walking with self-selected comfortable gait speed. Results: In the frontal plane, nearly all investigated kinematic and kinetic parameters showed a strong correlation with the SAC. The pelvis was raised on the contralateral side throughout the gait cycle with increasing SAC. During the prosthetic side stance phase, the mean shoulder obliquity and mean lateral trunk lean to the prosthetic side tended to be reduced with increased SAC. Prosthetic side hip abduction moment decreased with increasing SAC. Significance: The results confirm that transfemoral SAC contributes to pelvic stabilization and reduced compensatory movements of the pelvis and trunk. Transfemoral SAC of 6 ± 1° for bench alignment seems adequate for amputees with medium residual limb length. However, the optimum value for the individual patient may differ slightly.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: It is common practice to align transfemoral prosthetic sockets in adduction, due to the physiologic, adducted femoral alignment in unimpaired legs. An adducted femoral and socket alignment helps tightening hip abductors to stabilize the pelvis and reduce pelvic and trunk related compensatory movements. Research question: How do different socket adduction conditions (SAC) of transfemoral sockets affect pelvic and trunk stabilization during level ground walking in the frontal plane? Methods: Seven persons with transfemoral amputation with medium residual limb length participated in this study. The prosthetic alignment in the sagittal plane was performed according to established recommendations. SAC varied (0°, 3°, 6°, 9°). Kinematic and kinetic parameters were recorded in a gait laboratory with a 12-camera optoelectronic system and two piezoelectric force plates embedded in a 12-m walkway. The measurements were performed during level ground walking with self-selected comfortable gait speed. Results: In the frontal plane, nearly all investigated kinematic and kinetic parameters showed a strong correlation with the SAC. The pelvis was raised on the contralateral side throughout the gait cycle with increasing SAC. During the prosthetic side stance phase, the mean shoulder obliquity and mean lateral trunk lean to the prosthetic side tended to be reduced with increased SAC. Prosthetic side hip abduction moment decreased with increasing SAC. Significance: The results confirm that transfemoral SAC contributes to pelvic stabilization and reduced compensatory movements of the pelvis and trunk. Transfemoral SAC of 6 ± 1° for bench alignment seems adequate for amputees with medium residual limb length. However, the optimum value for the individual patient may differ slightly.
Waterval, N. F. J.; Brehm, M. -A.; Harlaar, J.; Nollet, F.
In: J. NeuroEng. Rehabil., Bd. 18, Nr. 1, 2021, ISSN: 1743-0003.
@article{Waterval2021,
title = {Individual stiffness optimization of dorsal leaf spring ankle-foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations},
author = {N. F. J. Waterval and M. -A. Brehm and J. Harlaar and F. Nollet},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2012344314&from=export},
doi = {10.1186/s12984-021-00890-8},
issn = {1743-0003},
year = {2021},
date = {2021-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {18},
number = {1},
address = {N.F.J. Waterval, Rehabilitation Medicine, Amsterdam Movement Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, Netherlands},
abstract = {Background: In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle-foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods: Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results: In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle-foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods: Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results: In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s
Yazdani, M.; Hajiaghaei, B.; Saeedi, H.; Kamali, M.; Yousefi, M.
In: Curr. Orthop. Pract., Bd. 32, Nr. 5, S. 505–511, 2021, ISSN: 1940-7041.
@article{Yazdani2021,
title = {Does the socket design affect symmetry and spatiotemporal gait parameters? A case series of two transfemoral amputees},
author = {M. Yazdani and B. Hajiaghaei and H. Saeedi and M. Kamali and M. Yousefi},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L635549609&from=export},
doi = {10.1097/bco.0000000000001022},
issn = {1940-7041},
year = {2021},
date = {2021-01-01},
journal = {Curr. Orthop. Pract.},
volume = {32},
number = {5},
pages = {505–511},
address = {B. Hajiaghaei, Department of Orthotics and Prosthetics, School of Rehabilitation Sciences, Iran University of Medical Sciences, Nezam Ave, Tehran, Iran},
abstract = {Background: Socket design is thought to improve gait performance and symmetry as the other components of the prosthesis do. This study focused on the comparison of two different sockets in transfemoral amputee patients to evaluate the influence of the socket designs on gait symmetry and various spatiotemporal gait parameters. Methods: Two transfemoral amputees participated in this case series study. They were asked to walk with the quadrilateral and the new modified sockets along a 10-meter walkway. The marker-based motion capture system recorded the spatiotemporal gait data during all walking trials. Kinematic data were compared between the two test conditions using the Wilcoxon signed-rank test and Symmetry Index. Results: The new socket increased velocity and cadence and reduced step width in both amputees, compared with the quadrilateral sockets. However, a good symmetry was observed in step length, stride length, step time, and stride time within two limbs by both sockets (SI ≤10). Conclusions: The design of sockets in this study had no observed effect on gait symmetry; however, the new socket increased velocity and cadence and reduced width step in both patients compared with the quadrilateral socket. Level of Evidence: Level IV.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: Socket design is thought to improve gait performance and symmetry as the other components of the prosthesis do. This study focused on the comparison of two different sockets in transfemoral amputee patients to evaluate the influence of the socket designs on gait symmetry and various spatiotemporal gait parameters. Methods: Two transfemoral amputees participated in this case series study. They were asked to walk with the quadrilateral and the new modified sockets along a 10-meter walkway. The marker-based motion capture system recorded the spatiotemporal gait data during all walking trials. Kinematic data were compared between the two test conditions using the Wilcoxon signed-rank test and Symmetry Index. Results: The new socket increased velocity and cadence and reduced step width in both amputees, compared with the quadrilateral sockets. However, a good symmetry was observed in step length, stride length, step time, and stride time within two limbs by both sockets (SI ≤10). Conclusions: The design of sockets in this study had no observed effect on gait symmetry; however, the new socket increased velocity and cadence and reduced width step in both patients compared with the quadrilateral socket. Level of Evidence: Level IV.
2019
Schmalz, T.; Schändlinger, J.; Schuler, M.; Bornmann, J.; Schirrmeister, B.; Kannenberg, A.; Ernst, M.
Biomechanical and metabolic effectiveness of an industrial exoskeleton for overhead work Artikel
In: Int. J. Environ. Res. Public Health, Bd. 16, Nr. 23, 2019, ISSN: 1661-7827.
@article{Schmalz2019,
title = {Biomechanical and metabolic effectiveness of an industrial exoskeleton for overhead work},
author = {T. Schmalz and J. Schändlinger and M. Schuler and J. Bornmann and B. Schirrmeister and A. Kannenberg and M. Ernst},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2003259386&from=export},
doi = {10.3390/ijerph16234792},
issn = {1661-7827},
year = {2019},
date = {2019-01-01},
journal = {Int. J. Environ. Res. Public Health},
volume = {16},
number = {23},
address = {T. Schmalz, Clinical Research & Services/Biomechanics, Otto Bock SE & Co. KGaA, Göttingen, Germany},
abstract = {Overhead work activities can lead to shoulder pain and serious musculoskeletal disorders (WMSD), such as rotator cuff injury and degeneration. Recently developed exoskeletons show promising results in supporting workers in such activities. In this study, a novel exoskeleton was investigated for two different overhead tasks with twelve participants. To investigate the effects of the device, electromyographic (EMG) signals of different shoulder and adjacent muscles as well as kinematic and metabolic parameters were analyzed with and without the exoskeleton. The mean EMG amplitude of all evaluated muscles was significantly reduced when the exoskeleton was used for the overhead tasks. This was accompanied by a reduction in both heart rate and oxygen rate. The kinematic analysis revealed small changes in the joint positions during the tasks. This study demonstrated the biomechanical and metabolic benefits of an exoskeleton designed to support overhead work activities. The results suggest improved physiological conditions and an unloading effect on the shoulder joint and muscles which are promising indicators that the exoskeleton may be a good solution to reduce shoulder WMSD among workers who carry out overhead tasks on a regular basis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Overhead work activities can lead to shoulder pain and serious musculoskeletal disorders (WMSD), such as rotator cuff injury and degeneration. Recently developed exoskeletons show promising results in supporting workers in such activities. In this study, a novel exoskeleton was investigated for two different overhead tasks with twelve participants. To investigate the effects of the device, electromyographic (EMG) signals of different shoulder and adjacent muscles as well as kinematic and metabolic parameters were analyzed with and without the exoskeleton. The mean EMG amplitude of all evaluated muscles was significantly reduced when the exoskeleton was used for the overhead tasks. This was accompanied by a reduction in both heart rate and oxygen rate. The kinematic analysis revealed small changes in the joint positions during the tasks. This study demonstrated the biomechanical and metabolic benefits of an exoskeleton designed to support overhead work activities. The results suggest improved physiological conditions and an unloading effect on the shoulder joint and muscles which are promising indicators that the exoskeleton may be a good solution to reduce shoulder WMSD among workers who carry out overhead tasks on a regular basis.
Volkmar, R.; Dosen, S.; Gonzalez-Vargas, J.; Baum, M.; Markovic, M.
Improving bimanual interaction with a prosthesis using semi-autonomous control Artikel
In: J. NeuroEng. Rehabil., Bd. 16, Nr. 1, 2019, ISSN: 1743-0003.
@article{Volkmar2019,
title = {Improving bimanual interaction with a prosthesis using semi-autonomous control},
author = {R. Volkmar and S. Dosen and J. Gonzalez-Vargas and M. Baum and M. Markovic},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L629849607&from=export},
doi = {10.1186/s12984-019-0617-6},
issn = {1743-0003},
year = {2019},
date = {2019-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {16},
number = {1},
address = {M. Markovic, Department of Trauma Surgery Orthopedics and Plastic Surgery, University Medical Center Göttingen, Von-Siebold-Str. 3, Göttingen, Germany},
abstract = {Background: The loss of a hand is a traumatic experience that substantially compromises an individual's capability to interact with his environment. The myoelectric prostheses are state-of-the-art (SoA) functional replacements for the lost limbs. Their overall mechanical design and dexterity have improved over the last few decades, but the users have not been able to fully exploit these advances because of the lack of effective and intuitive control. Bimanual tasks are particularly challenging for an amputee since prosthesis control needs to be coordinated with the movement of the sound limb. So far, the bimanual activities have been often neglected by the prosthetic research community. Methods: We present a novel method to prosthesis control, which uses a semi-autonomous approach in order to simplify bimanual interactions. The approach supplements the commercial SoA two-channel myoelectric control with two additional sensors. Two inertial measurement units were attached to the prosthesis and the sound hand to detect the movement of both limbs. Once a bimanual interaction is detected, the system mimics the coordination strategies of able-bodied subjects to automatically adjust the prosthesis wrist rotation (pronation, supination) and grip type (lateral, palmar) to assist the sound hand during a bimanual task. The system has been evaluated in eight able-bodied subjects performing functional uni- A nd bi-manual tasks using the novel method and SoA two-channel myocontrol. The outcome measures were time to accomplish the task, semi-autonomous system misclassification rate, subjective rating of intuitiveness, and perceived workload (NASA TLX). Results: The results demonstrated that the novel control interface substantially outperformed the SoA myoelectric control. While using the semi-autonomous control the time to accomplish the task and the perceived workload decreased for 25 and 27%, respectively, while the subjects rated the system as more intuitive then SoA myocontrol. Conclusions: The novel system uses minimal additional hardware (two inertial sensors) and simple processing and it is therefore convenient for practical implementation. By using the proposed control scheme, the prosthesis assists the user's sound hand in performing bimanual interactions while decreasing cognitive burden.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: The loss of a hand is a traumatic experience that substantially compromises an individual's capability to interact with his environment. The myoelectric prostheses are state-of-the-art (SoA) functional replacements for the lost limbs. Their overall mechanical design and dexterity have improved over the last few decades, but the users have not been able to fully exploit these advances because of the lack of effective and intuitive control. Bimanual tasks are particularly challenging for an amputee since prosthesis control needs to be coordinated with the movement of the sound limb. So far, the bimanual activities have been often neglected by the prosthetic research community. Methods: We present a novel method to prosthesis control, which uses a semi-autonomous approach in order to simplify bimanual interactions. The approach supplements the commercial SoA two-channel myoelectric control with two additional sensors. Two inertial measurement units were attached to the prosthesis and the sound hand to detect the movement of both limbs. Once a bimanual interaction is detected, the system mimics the coordination strategies of able-bodied subjects to automatically adjust the prosthesis wrist rotation (pronation, supination) and grip type (lateral, palmar) to assist the sound hand during a bimanual task. The system has been evaluated in eight able-bodied subjects performing functional uni- A nd bi-manual tasks using the novel method and SoA two-channel myocontrol. The outcome measures were time to accomplish the task, semi-autonomous system misclassification rate, subjective rating of intuitiveness, and perceived workload (NASA TLX). Results: The results demonstrated that the novel control interface substantially outperformed the SoA myoelectric control. While using the semi-autonomous control the time to accomplish the task and the perceived workload decreased for 25 and 27%, respectively, while the subjects rated the system as more intuitive then SoA myocontrol. Conclusions: The novel system uses minimal additional hardware (two inertial sensors) and simple processing and it is therefore convenient for practical implementation. By using the proposed control scheme, the prosthesis assists the user's sound hand in performing bimanual interactions while decreasing cognitive burden.
2017
Rigney, S. M.; Simmons, A.; Kark, L.
Mechanical characterization and comparison of energy storage and return prostheses Artikel
In: Med. Eng. Phys., Bd. 41, S. 90–96, 2017, ISSN: 1350-4533.
@article{Rigney2017,
title = {Mechanical characterization and comparison of energy storage and return prostheses},
author = {S. M. Rigney and A. Simmons and L. Kark},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L614136635&from=export},
doi = {10.1016/j.medengphy.2017.01.003},
issn = {1350-4533},
year = {2017},
date = {2017-01-01},
journal = {Med. Eng. Phys.},
volume = {41},
pages = {90–96},
address = {L. Kark, Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia},
abstract = {The suitability of finite element analysis (FEA) for standardizing the mechanical characterization of energy storage and return (ESAR) prostheses was investigated. A methodology consisting of both experimental and numerical analysis was proposed and trialed for the Vari-flex® ModularTM, Flex-foot Cheetah and Cheetah Xtreme by Össur® and a 1E90 Sprinter by Ottobock®. Gait analysis was conducted to determine suitable orientation angles for non-destructive testing (NDT) of the ESAR prostheses followed by a quasi-static inverse FEA procedure within COMSOL Multiphysics®, where the NDT conditions were replicated to determine the homogenized material properties of the prostheses. The prostheses’ loading response under bodyweight for an 80 kg person was then simulated, using both Eigenfrequency and time-dependent analysis. The apparent stiffness under bodyweight was determined to be 94.7, 48.6, 57.4 and 65.0 Nmm−1 for the Vari-flex® ModularTM, Flex-foot Cheetah, Cheetah Xtreme and 1E90 Sprinter, respectively. Both the energy stored and returned by the prostheses varied negatively with stiffness, yet the overall efficiency of the prostheses were similar, at 52.7, 52.0, 51.7 and 52.4% for the abovementioned prostheses. The proposed methodology allows the standardized assessment and comparison of ESAR prostheses without the confounding influences of subject-specific gait characteristics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The suitability of finite element analysis (FEA) for standardizing the mechanical characterization of energy storage and return (ESAR) prostheses was investigated. A methodology consisting of both experimental and numerical analysis was proposed and trialed for the Vari-flex® ModularTM, Flex-foot Cheetah and Cheetah Xtreme by Össur® and a 1E90 Sprinter by Ottobock®. Gait analysis was conducted to determine suitable orientation angles for non-destructive testing (NDT) of the ESAR prostheses followed by a quasi-static inverse FEA procedure within COMSOL Multiphysics®, where the NDT conditions were replicated to determine the homogenized material properties of the prostheses. The prostheses’ loading response under bodyweight for an 80 kg person was then simulated, using both Eigenfrequency and time-dependent analysis. The apparent stiffness under bodyweight was determined to be 94.7, 48.6, 57.4 and 65.0 Nmm−1 for the Vari-flex® ModularTM, Flex-foot Cheetah, Cheetah Xtreme and 1E90 Sprinter, respectively. Both the energy stored and returned by the prostheses varied negatively with stiffness, yet the overall efficiency of the prostheses were similar, at 52.7, 52.0, 51.7 and 52.4% for the abovementioned prostheses. The proposed methodology allows the standardized assessment and comparison of ESAR prostheses without the confounding influences of subject-specific gait characteristics.
Pröbsting, E.; Kannenberg, A.; Zacharias, B.
In: Prosthet. Orthot. Int., Bd. 41, Nr. 1, S. 65–77, 2017, ISSN: 0309-3646.
@article{Proebsting2017,
title = {Safety and walking ability of KAFO users with the C-Brace® Orthotronic Mobility System, a new microprocessor stance and swing control orthosis},
author = {E. Pröbsting and A. Kannenberg and B. Zacharias},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L614321344&from=export},
doi = {10.1177/0309364616637954},
issn = {0309-3646},
year = {2017},
date = {2017-01-01},
journal = {Prosthet. Orthot. Int.},
volume = {41},
number = {1},
pages = {65–77},
address = {E. Pröbsting, Otto Bock HealthCare GmbH, Department Clinical Research and Services, Goettingen, Germany},
abstract = {Background: There are clear indications for benefits of stance control orthoses compared to locked knee ankle foot orthoses. However, stance control orthoses still have limited function compared with a sound human leg. Objectives: The aim of this study was to evaluate the potential benefits of a microprocessor stance and swing control orthosis compared to stance control orthoses and locked knee ankle foot orthoses in activities of daily living. Study design: Survey of lower limb orthosis users before and after fitting of a microprocessor stance and swing control orthosis. Methods: Thirteen patients with various lower limb pareses completed a baseline survey for their current orthotic device (locked knee ankle foot orthosis or stance control orthosis) and a follow-up for the microprocessor stance and swing control orthosis with the Orthosis Evaluation Questionnaire, a new self-reported outcome measure devised by modifying the Prosthesis Evaluation Questionnaire for use in lower limb orthotics and the Activities of Daily Living Questionnaire. Results: The Orthosis Evaluation Questionnaire results demonstrated significant improvements by microprocessor stance and swing control orthosis use in the total score and the domains of ambulation (p =.001), paretic limb health (p =.04), sounds (p =.02), and well-being (p =.01). Activities of Daily Living Questionnaire results showed significant improvements with the microprocessor stance and swing control orthosis with regard to perceived safety and difficulty of activities of daily living. Conclusion: The microprocessor stance and swing control orthosis may facilitate an easier, more physiological, and safer execution of many activities of daily living compared to traditional leg orthosis technologies. Clinical relevance This study compared patient-reported outcomes of a microprocessor stance and swing control orthosis (C-Brace) to those with traditional knee ankle foot orthosis and stance control orthosis devices. The C-Brace offers new functions including controlled knee flexion during weight bearing and dynamic swing control, resulting in significant improvements in perceived orthotic mobility and safety.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: There are clear indications for benefits of stance control orthoses compared to locked knee ankle foot orthoses. However, stance control orthoses still have limited function compared with a sound human leg. Objectives: The aim of this study was to evaluate the potential benefits of a microprocessor stance and swing control orthosis compared to stance control orthoses and locked knee ankle foot orthoses in activities of daily living. Study design: Survey of lower limb orthosis users before and after fitting of a microprocessor stance and swing control orthosis. Methods: Thirteen patients with various lower limb pareses completed a baseline survey for their current orthotic device (locked knee ankle foot orthosis or stance control orthosis) and a follow-up for the microprocessor stance and swing control orthosis with the Orthosis Evaluation Questionnaire, a new self-reported outcome measure devised by modifying the Prosthesis Evaluation Questionnaire for use in lower limb orthotics and the Activities of Daily Living Questionnaire. Results: The Orthosis Evaluation Questionnaire results demonstrated significant improvements by microprocessor stance and swing control orthosis use in the total score and the domains of ambulation (p =.001), paretic limb health (p =.04), sounds (p =.02), and well-being (p =.01). Activities of Daily Living Questionnaire results showed significant improvements with the microprocessor stance and swing control orthosis with regard to perceived safety and difficulty of activities of daily living. Conclusion: The microprocessor stance and swing control orthosis may facilitate an easier, more physiological, and safer execution of many activities of daily living compared to traditional leg orthosis technologies. Clinical relevance This study compared patient-reported outcomes of a microprocessor stance and swing control orthosis (C-Brace) to those with traditional knee ankle foot orthosis and stance control orthosis devices. The C-Brace offers new functions including controlled knee flexion during weight bearing and dynamic swing control, resulting in significant improvements in perceived orthotic mobility and safety.
2016
Beck, O. N.; Taboga, P.; Grabowski, A. M.
Characterizing the mechanical properties of running-specific prostheses Artikel
In: PLoS ONE, Bd. 11, Nr. 12, 2016, ISSN: 1932-6203.
@article{Beck2016,
title = {Characterizing the mechanical properties of running-specific prostheses},
author = {O. N. Beck and P. Taboga and A. M. Grabowski},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L613668924&from=export},
doi = {10.1371/journal.pone.0168298},
issn = {1932-6203},
year = {2016},
date = {2016-01-01},
journal = {PLoS ONE},
volume = {11},
number = {12},
abstract = {The mechanical stiffness of running-specific prostheses likely affects the functional abilities of athletes with leg amputations. However, each prosthetic manufacturer recommends prostheses based on subjective stiffness categories rather than performance based metrics. The actual mechanical stiffness values of running-specific prostheses (i.e. kN/m) are unknown. Consequently, we sought to characterize and disseminate the stiffness values of running-specific prostheses so that researchers, clinicians, and athletes can objectively evaluate prosthetic function. We characterized the stiffness values of 55 running-specific prostheses across various models, stiffness categories, and heights using forces and angles representative of those measured from athletes with transtibial amputations during running. Characterizing prosthetic force-displacement profiles with a 2nd degree polynomial explained 4.4% more of the variance than a linear function (p<0.001). The prosthetic stiffness values of manufacturer recommended stiffness categories varied between prosthetic models (p<0.001). Also, prosthetic stiffness was 10% to 39% less at angles typical of running 3 m/s and 6 m/s (10?-25?) compared to neutral (0?) (p<0.001). Furthermore, prosthetic stiffness was inversely related to height in J-shaped (p<0.001), but not C-shaped, prostheses. Running-specific prostheses should be tested under the demands of the respective activity in order to derive relevant characterizations of stiffness and function. In all, our results indicate that when athletes with leg amputations alter prosthetic model, height, and/ or sagittal plane alignment, their prosthetic stiffness profiles also change; therefore variations in comfort, performance, etc. may be indirectly due to altered stiffness.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The mechanical stiffness of running-specific prostheses likely affects the functional abilities of athletes with leg amputations. However, each prosthetic manufacturer recommends prostheses based on subjective stiffness categories rather than performance based metrics. The actual mechanical stiffness values of running-specific prostheses (i.e. kN/m) are unknown. Consequently, we sought to characterize and disseminate the stiffness values of running-specific prostheses so that researchers, clinicians, and athletes can objectively evaluate prosthetic function. We characterized the stiffness values of 55 running-specific prostheses across various models, stiffness categories, and heights using forces and angles representative of those measured from athletes with transtibial amputations during running. Characterizing prosthetic force-displacement profiles with a 2nd degree polynomial explained 4.4% more of the variance than a linear function (p<0.001). The prosthetic stiffness values of manufacturer recommended stiffness categories varied between prosthetic models (p<0.001). Also, prosthetic stiffness was 10% to 39% less at angles typical of running 3 m/s and 6 m/s (10?-25?) compared to neutral (0?) (p<0.001). Furthermore, prosthetic stiffness was inversely related to height in J-shaped (p<0.001), but not C-shaped, prostheses. Running-specific prostheses should be tested under the demands of the respective activity in order to derive relevant characterizations of stiffness and function. In all, our results indicate that when athletes with leg amputations alter prosthetic model, height, and/ or sagittal plane alignment, their prosthetic stiffness profiles also change; therefore variations in comfort, performance, etc. may be indirectly due to altered stiffness.
Schweisfurth, M. A.; Markovic, M.; Dosen, S.; Teich, F.; Graimann, B.; Farina, D.
Electrotactile EMG feedback improves the control of prosthesis grasping force Artikel
In: J. Neural Eng., Bd. 13, Nr. 5, 2016, ISSN: 1741-2560.
@article{Schweisfurth2016,
title = {Electrotactile EMG feedback improves the control of prosthesis grasping force},
author = {M. A. Schweisfurth and M. Markovic and S. Dosen and F. Teich and B. Graimann and D. Farina},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L612465506&from=export},
doi = {10.1088/1741-2560/13/5/056010},
issn = {1741-2560},
year = {2016},
date = {2016-01-01},
journal = {J. Neural Eng.},
volume = {13},
number = {5},
address = {D. Farina, Institute for NeuroRehabilitation Systems, University Medical Center Göttingen, Georg-August University, Göttingen, Germany},
abstract = {Objective. A drawback of active prostheses is that they detach the subject from the produced forces, thereby preventing direct mechanical feedback. This can be compensated by providing somatosensory feedback to the user through mechanical or electrical stimulation, which in turn may improve the utility, sense of embodiment, and thereby increase the acceptance rate. Approach. In this study, we compared a novel approach to closing the loop, namely EMG feedback (emgFB), to classic force feedback (forceFB), using electrotactile interface in a realistic task setup. Eleven intact-bodied subjects and one transradial amputee performed a routine grasping task while receiving emgFB or forceFB. The two feedback types were delivered through the same electrotactile interface, using a mixed spatial/frequency coding to transmit 8 discrete levels of the feedback variable. In emgFB, the stimulation transmitted the amplitude of the processed myoelectric signal generated by the subject (prosthesis input), and in forceFB the generated grasping force (prosthesis output). The task comprised 150 trials of routine grasping at six forces, randomly presented in blocks of five trials (same force). Interquartile range and changes in the absolute error (AE) distribution (magnitude and dispersion) with respect to the target level were used to assess precision and overall performance, respectively. Main results. Relative to forceFB, emgFB significantly improved the precision of myoelectric commands (min/max of the significant levels) for 23%/36% as well as the precision of force control for 12%/32%, in intact-bodied subjects. Also, the magnitude and dispersion of the AE distribution were reduced. The results were similar in the amputee, showing considerable improvements. Significance. Using emgFB, the subjects therefore decreased the uncertainty of the forward pathway. Since there is a correspondence between the EMG and force, where the former anticipates the latter, the emgFB allowed for predictive control, as the subjects used the feedback to adjust the desired force even before the prosthesis contacted the object. In conclusion, the online emgFB was superior to the classic forceFB in realistic conditions that included electrotactile stimulation, limited feedback resolution (8 levels), cognitive processing delay, and time constraints (fast grasping).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Objective. A drawback of active prostheses is that they detach the subject from the produced forces, thereby preventing direct mechanical feedback. This can be compensated by providing somatosensory feedback to the user through mechanical or electrical stimulation, which in turn may improve the utility, sense of embodiment, and thereby increase the acceptance rate. Approach. In this study, we compared a novel approach to closing the loop, namely EMG feedback (emgFB), to classic force feedback (forceFB), using electrotactile interface in a realistic task setup. Eleven intact-bodied subjects and one transradial amputee performed a routine grasping task while receiving emgFB or forceFB. The two feedback types were delivered through the same electrotactile interface, using a mixed spatial/frequency coding to transmit 8 discrete levels of the feedback variable. In emgFB, the stimulation transmitted the amplitude of the processed myoelectric signal generated by the subject (prosthesis input), and in forceFB the generated grasping force (prosthesis output). The task comprised 150 trials of routine grasping at six forces, randomly presented in blocks of five trials (same force). Interquartile range and changes in the absolute error (AE) distribution (magnitude and dispersion) with respect to the target level were used to assess precision and overall performance, respectively. Main results. Relative to forceFB, emgFB significantly improved the precision of myoelectric commands (min/max of the significant levels) for 23%/36% as well as the precision of force control for 12%/32%, in intact-bodied subjects. Also, the magnitude and dispersion of the AE distribution were reduced. The results were similar in the amputee, showing considerable improvements. Significance. Using emgFB, the subjects therefore decreased the uncertainty of the forward pathway. Since there is a correspondence between the EMG and force, where the former anticipates the latter, the emgFB allowed for predictive control, as the subjects used the feedback to adjust the desired force even before the prosthesis contacted the object. In conclusion, the online emgFB was superior to the classic forceFB in realistic conditions that included electrotactile stimulation, limited feedback resolution (8 levels), cognitive processing delay, and time constraints (fast grasping).
Williams, M. R.; D'Andrea, S.; Herr, H. M.
Impact on gait biomechanics of using an active variable impedance prosthetic knee Artikel
In: J. NeuroEng. Rehabil., Bd. 13, Nr. 1, 2016, ISSN: 1743-0003.
@article{Williams2016,
title = {Impact on gait biomechanics of using an active variable impedance prosthetic knee},
author = {M. R. Williams and S. D'Andrea and H. M. Herr},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L610660431&from=export},
doi = {10.1186/s12984-016-0159-0},
issn = {1743-0003},
year = {2016},
date = {2016-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {13},
number = {1},
address = {M.R. Williams, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, United States},
abstract = {Background: An above knee amputation can have a significant impact on gait, with substantial deviations in inter-leg symmetry, step length, hip exertion and upper body involvement even when using a current clinical standard of care prosthesis. These differences can produce gait that is less efficient and less comfortable, resulting in slower and shorter distance walking, particularly with long term use. Methods: A robotic variable impedance prosthetic knee (VI Knee) was tested with five individuals (N = 5) with unilateral amputation above the knee at fixed speeds both above and below their normal walking speed. Subject gait was measured as they walked along an instrumented walkway via optical motion capture and force plates in the floor. Each subject's gait while using the VI Knee was compared to that while using their standard of care knee (OttoBock C-Leg). Results: Significant differences (p < 0.05) in walking between the standard of care and variable impedance devices were seen in step length and hip range of motion symmetries, hip extension moment, knee power and torso lean angle. While using the VI Knee, several subjects demonstrated statistically significant improvements in gait, particularly in increased hip range of motion symmetry between affected and intact sides, greater prosthesis knee power and in reducing upper body involvement in the walking task by decreasing forward and affected side lean and reducing the pelvis-torso twist coupling. These changes to torso posture during gait also resulted in increased terminal stance hip flexion moment across subjects. Detriments to gait were also observed in that some subjects exhibited decreased step length symmetry while using the VI Knee compared to the C-Leg. Conclusions: The knee tested represents the potential to improve gait biomechanics and reduce upper body involvement in persons with above knee amputation compared to current standard of care devices. While using the VI Knee, subjects demonstrated statistically significant improvements in several aspects of gait though some were worsened while using the device. It is possible that these negative effects may be mitigated through longer term training and experience with the VI Knee. Given the demonstrated benefits and the potential to reduce or eliminate detriments through training, using a powered device like the VI Knee, particularly over an extended period of time, may help to improve walking performance and comfort.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: An above knee amputation can have a significant impact on gait, with substantial deviations in inter-leg symmetry, step length, hip exertion and upper body involvement even when using a current clinical standard of care prosthesis. These differences can produce gait that is less efficient and less comfortable, resulting in slower and shorter distance walking, particularly with long term use. Methods: A robotic variable impedance prosthetic knee (VI Knee) was tested with five individuals (N = 5) with unilateral amputation above the knee at fixed speeds both above and below their normal walking speed. Subject gait was measured as they walked along an instrumented walkway via optical motion capture and force plates in the floor. Each subject's gait while using the VI Knee was compared to that while using their standard of care knee (OttoBock C-Leg). Results: Significant differences (p < 0.05) in walking between the standard of care and variable impedance devices were seen in step length and hip range of motion symmetries, hip extension moment, knee power and torso lean angle. While using the VI Knee, several subjects demonstrated statistically significant improvements in gait, particularly in increased hip range of motion symmetry between affected and intact sides, greater prosthesis knee power and in reducing upper body involvement in the walking task by decreasing forward and affected side lean and reducing the pelvis-torso twist coupling. These changes to torso posture during gait also resulted in increased terminal stance hip flexion moment across subjects. Detriments to gait were also observed in that some subjects exhibited decreased step length symmetry while using the VI Knee compared to the C-Leg. Conclusions: The knee tested represents the potential to improve gait biomechanics and reduce upper body involvement in persons with above knee amputation compared to current standard of care devices. While using the VI Knee, subjects demonstrated statistically significant improvements in several aspects of gait though some were worsened while using the device. It is possible that these negative effects may be mitigated through longer term training and experience with the VI Knee. Given the demonstrated benefits and the potential to reduce or eliminate detriments through training, using a powered device like the VI Knee, particularly over an extended period of time, may help to improve walking performance and comfort.
Hahn, A.; Lang, M.; Stuckart, C.
In: Medicine, Bd. 95, Nr. 45, 2016, ISSN: 0025-7974.
@article{Hahn2016,
title = {Analysis of clinically important factors on the performance of advanced hydraulic, microprocessor-controlled exo-prosthetic knee joints based on 899 trial fittings},
author = {A. Hahn and M. Lang and C. Stuckart},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L613375887&from=export},
doi = {10.1097/md.0000000000005386},
issn = {0025-7974},
year = {2016},
date = {2016-01-01},
journal = {Medicine},
volume = {95},
number = {45},
address = {A. Hahn, Otto Bock Healthcare Products GmbH, Brehmstrasse 16, Vienna, Austria},
abstract = {The objective of this work is to evaluate whether clinically important factors may predict an individual's capability to utilize the functional benefits provided by an advanced hydraulic, microprocessor-controlled exo-prosthetic knee component. This retrospective cross-sectional cohort analysis investigated the data of above knee amputees captured during routine trial fittings. Prosthetists rated the performance indicators showing the functional benefits of the advanced maneuvering capabilities of the device. Subjects were asked to rate their perception. Simple and multiple linear and logistic regression was applied. Data from 899 subjects with demographics typical for the population were evaluated. Ability to vary gait speed, perform toileting, and ascend stairs were identified as the most sensitive performance predictors. Prior C-Leg users showed benefits during advanced maneuvering. Variables showed plausible and meaningful effects, however, could not claim predictive power. Mobility grade showed the largest effect but also failed to be predictive. Clinical parameters such as etiology, age, mobility grade, and others analyzed here do not suffice to predict individual potential. Daily walking distance may pose a threshold value and be part of a predictive instrument. Decisions based solely on single parameters such as mobility grade rating or walking distance seem to be questionable.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The objective of this work is to evaluate whether clinically important factors may predict an individual's capability to utilize the functional benefits provided by an advanced hydraulic, microprocessor-controlled exo-prosthetic knee component. This retrospective cross-sectional cohort analysis investigated the data of above knee amputees captured during routine trial fittings. Prosthetists rated the performance indicators showing the functional benefits of the advanced maneuvering capabilities of the device. Subjects were asked to rate their perception. Simple and multiple linear and logistic regression was applied. Data from 899 subjects with demographics typical for the population were evaluated. Ability to vary gait speed, perform toileting, and ascend stairs were identified as the most sensitive performance predictors. Prior C-Leg users showed benefits during advanced maneuvering. Variables showed plausible and meaningful effects, however, could not claim predictive power. Mobility grade showed the largest effect but also failed to be predictive. Clinical parameters such as etiology, age, mobility grade, and others analyzed here do not suffice to predict individual potential. Daily walking distance may pose a threshold value and be part of a predictive instrument. Decisions based solely on single parameters such as mobility grade rating or walking distance seem to be questionable.
2015
Hausmann, J.; Sweeney-Reed, C. M.; Sobieray, U.; Matzke, M.; Heinze, H. -J.; Voges, J.; Buentjen, L.
In: J. NeuroEng. Rehabil., Bd. 12, Nr. 1, 2015, ISSN: 1743-0003.
@article{Hausmann2015,
title = {Functional electrical stimulation through direct 4-channel nerve stimulation to improve gait in multiple sclerosis: a feasibility study},
author = {J. Hausmann and C. M. Sweeney-Reed and U. Sobieray and M. Matzke and H. -J. Heinze and J. Voges and L. Buentjen},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L606904897&from=export},
doi = {10.1186/s12984-015-0096-3},
issn = {1743-0003},
year = {2015},
date = {2015-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {12},
number = {1},
address = {J. Hausmann, Department of Neurology, Otto-von-Guericke University, Magdeburg, Leipziger Str. 44, Magdeburg, Germany},
abstract = {Background: Gait dysfunction due to lower limb central paralysis, frequently involving drop foot, is a common cause of disability in multiple sclerosis and has been treated with transcutaneous functional electrical stimulation (FES). We provide here the first report of 4-channel semi-implantable FES of the peroneal nerve which has been successfully used for rehabilitation in patients following stroke. Methods: FES was implemented via a 4-channel semi-implantable closed-loop system (ActiGait®, ©Ottobock), generating dorsiflexion in drop foot. Walking distance, gait symmetry (temporospatial gait analyses, Vicon Motion Systems®), gait velocity (10 m walking test) and quality of life (SF-36 questionnaire) were measured to evaluate the therapeutic benefit of this system in two patients with progressive MS. Results: Walking distance increased from 517 to 1884 m in Patient 1 and from 52 to 506 m in Patient 2. Gait velocity did not change significantly in Patient 1 and increased from 0.6 to 0.8 m/s in Patient 2. Maximum deviations of center of mass from the midline to each side changed significantly after 3 months of stimulation compared to baseline, decreasing from 15 to 12 mm in Patient 1 and from 47 to 37 mm in Patient 2. Both patients experienced reduced pain and fatigue and benefits to quality of life. Adverse events did not occur during the observation period. Conclusion: We conclude that implantable 4-channel FES systems are not only feasible but present a promising new alternative for treating central drop foot in MS patients.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: Gait dysfunction due to lower limb central paralysis, frequently involving drop foot, is a common cause of disability in multiple sclerosis and has been treated with transcutaneous functional electrical stimulation (FES). We provide here the first report of 4-channel semi-implantable FES of the peroneal nerve which has been successfully used for rehabilitation in patients following stroke. Methods: FES was implemented via a 4-channel semi-implantable closed-loop system (ActiGait®, ©Ottobock), generating dorsiflexion in drop foot. Walking distance, gait symmetry (temporospatial gait analyses, Vicon Motion Systems®), gait velocity (10 m walking test) and quality of life (SF-36 questionnaire) were measured to evaluate the therapeutic benefit of this system in two patients with progressive MS. Results: Walking distance increased from 517 to 1884 m in Patient 1 and from 52 to 506 m in Patient 2. Gait velocity did not change significantly in Patient 1 and increased from 0.6 to 0.8 m/s in Patient 2. Maximum deviations of center of mass from the midline to each side changed significantly after 3 months of stimulation compared to baseline, decreasing from 15 to 12 mm in Patient 1 and from 47 to 37 mm in Patient 2. Both patients experienced reduced pain and fatigue and benefits to quality of life. Adverse events did not occur during the observation period. Conclusion: We conclude that implantable 4-channel FES systems are not only feasible but present a promising new alternative for treating central drop foot in MS patients.
2013
Fligge, N.; Urbanek, H.; der Smagt, P. Van
Relation between object properties and EMG during reaching to grasp Artikel
In: J. Electromyogr. Kinesiology, Bd. 23, Nr. 2, S. 402–410, 2013, ISSN: 1873-5711.
@article{Fligge2013,
title = {Relation between object properties and EMG during reaching to grasp},
author = {N. Fligge and H. Urbanek and P. Van der Smagt},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L52331059&from=export},
doi = {10.1016/j.jelekin.2012.10.010},
issn = {1873-5711},
year = {2013},
date = {2013-01-01},
journal = {J. Electromyogr. Kinesiology},
volume = {23},
number = {2},
pages = {402–410},
address = {N. Fligge, German Aerospace Center (DLR), Center for Robotics and Mechatronics, Muenchner Strasse 20, D-82234 Oberpfaffenhofen-Wessling, Germany},
abstract = {In order to stably grasp an object with an artificial hand, a priori knowledge of the object's properties is a major advantage, especially to ensure subsequent manipulation of the object held by the hand. This is also true for hand prostheses: pre-shaping of the hand while approaching the object, similar to able-bodied, allows the wearer for a much faster and more intuitive way of handling and grasping an object. For hand prostheses, it would be advantageous to obtain this information about object properties from a surface electromyography (sEMG) signal, which is already present and used to control the active prosthetic hand.We describe experiments in which human subjects grasp different objects at different positions while their muscular activity is recorded through eight sEMG electrodes placed on the forearm. Results show that sEMG data, gathered before the hand is in contact with the object, can be used to obtain relevant information on object properties such as size and weight. © 2012 Elsevier Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In order to stably grasp an object with an artificial hand, a priori knowledge of the object's properties is a major advantage, especially to ensure subsequent manipulation of the object held by the hand. This is also true for hand prostheses: pre-shaping of the hand while approaching the object, similar to able-bodied, allows the wearer for a much faster and more intuitive way of handling and grasping an object. For hand prostheses, it would be advantageous to obtain this information about object properties from a surface electromyography (sEMG) signal, which is already present and used to control the active prosthetic hand.We describe experiments in which human subjects grasp different objects at different positions while their muscular activity is recorded through eight sEMG electrodes placed on the forearm. Results show that sEMG data, gathered before the hand is in contact with the object, can be used to obtain relevant information on object properties such as size and weight. © 2012 Elsevier Ltd.
2010
Ludwigs, E.; Bellmann, M.; Schmalz, T.; Blumentritt, S.
Biomechanical differences between two exoprosthetic hip joint systems during level walking Artikel
In: Prosthet. Orthot. Int., Bd. 34, Nr. 4, S. 449–460, 2010, ISSN: 1746-1553.
@article{Ludwigs2010,
title = {Biomechanical differences between two exoprosthetic hip joint systems during level walking},
author = {E. Ludwigs and M. Bellmann and T. Schmalz and S. Blumentritt},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L360015209&from=export},
doi = {10.3109/03093646.2010.499551},
issn = {1746-1553},
year = {2010},
date = {2010-01-01},
journal = {Prosthet. Orthot. Int.},
volume = {34},
number = {4},
pages = {449–460},
address = {E. Ludwigs, Research Department, Otto Bock HealthCare GmbH, Hermann-Rein-Str. 2a, Gttingen, 37075, Germany},
abstract = {Previous studies have shown low end-user acceptance of a hip disarticulation style prosthesis and that the limitations of such prostheses, including poor gait pattern, socket discomfort, weight of the prosthesis, loss of mobility, instability and high energy consumption are a contributing factor. This study was initiated to determine if a new style of prosthetic hip joint could help to overcome some of the limitations concerning the gait pattern. The present study analyzed the gait pattern of six hip disarticulation amputee subjects. The objective was to compare two different prosthetic hip joints, both from Otto Bock HealthCare: The new Helix3D and the 7E7, which is based on the Canadian model proposed by McLaurin (1954). Kinematics and kinetics were recorded by an optoelectronic camera system with six CCD cameras and two force plates. During weight acceptance, the Helix3D extends considerably slower and reaches full extension later than the 7E7. The increased range of pelvic tilt observed with hip disarticulation amputees is significantly reduced (by 5±3 degrees) when using the Helix3D Hip Joint. In addition, this system showed increased stance phase knee joint flexion as well as increased maximum swing phase knee flexion angles compared to the 7E7. These motion analysis results show that the Helix3D Hip Joint can reduce gait abnormalities compared to the uniplanar design of the 7E7 hip joint. © 2010 ISPO.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Previous studies have shown low end-user acceptance of a hip disarticulation style prosthesis and that the limitations of such prostheses, including poor gait pattern, socket discomfort, weight of the prosthesis, loss of mobility, instability and high energy consumption are a contributing factor. This study was initiated to determine if a new style of prosthetic hip joint could help to overcome some of the limitations concerning the gait pattern. The present study analyzed the gait pattern of six hip disarticulation amputee subjects. The objective was to compare two different prosthetic hip joints, both from Otto Bock HealthCare: The new Helix3D and the 7E7, which is based on the Canadian model proposed by McLaurin (1954). Kinematics and kinetics were recorded by an optoelectronic camera system with six CCD cameras and two force plates. During weight acceptance, the Helix3D extends considerably slower and reaches full extension later than the 7E7. The increased range of pelvic tilt observed with hip disarticulation amputees is significantly reduced (by 5±3 degrees) when using the Helix3D Hip Joint. In addition, this system showed increased stance phase knee joint flexion as well as increased maximum swing phase knee flexion angles compared to the 7E7. These motion analysis results show that the Helix3D Hip Joint can reduce gait abnormalities compared to the uniplanar design of the 7E7 hip joint. © 2010 ISPO.
2004
Wit, D. C. M.; Buurke, J. H.; Nijlant, J. M. M.; IJzerman, M. J.; Hermens, H. J.
In: Clin. Rehabil., Bd. 18, Nr. 5, S. 550–557, 2004, ISSN: 0269-2155.
@article{Wit2004,
title = {The effect of an ankle-foot orthosis on walking ability in chronic stroke patients: A randomized controlled trial},
author = {D. C. M. Wit and J. H. Buurke and J. M. M. Nijlant and M. J. IJzerman and H. J. Hermens},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L39076880&from=export},
doi = {10.1191/0269215504cr770oa},
issn = {0269-2155},
year = {2004},
date = {2004-01-01},
journal = {Clin. Rehabil.},
volume = {18},
number = {5},
pages = {550–557},
address = {D.C.M. de Wit, Roessingh Research and Development, Roessinghbleekweg 33B, 7522 AH Enschede, Netherlands},
abstract = {Objective: Regaining walking ability is a major goal during the rehabilitation of stroke patients. To support this process an ankle-foot orthosis (AFC) is often prescribed. The aim of this study is to investigate the effect of an AFO on walking ability in chronic stroke patients. Design: Cross-over design with randomization for the interventions. Methods: Twenty chronic stroke patients, wearing an AFO for at least six months, were included. Walking ability was operationalized as comfortable walking speed, scores on the timed up and go (TUG) test and stairs test. Patients were measured with and without their AFO, the sequence of which was randomized. Additionally, subjective impressions of self-confidence and difficulty of the tasks were scored. Clinically relevant differences based on literature were defined for walking speed (20 cm/s), the TUG test (10 s). Gathered data were statistically analysed using a paired t-test. Results: The mean difference in favour of the AFO in walking speed was 4.8 cm/s (95% CI 0.85-8.7), in the TUG test 3.6 s (95% CI 2.4-4.8) and in the stairs test 8.6 s (95% CI 3.1-14.1). Sixty-five per cent of the patients experienced less difficulty and 70% of the patients felt more self-confident while wearing the AFO. Conclusions: The effect of an AFO on walking ability is statistically significant, but compared with the a priori defined differences it is too small to be clinically relevant. The effect on self-confidence suggests that other factors might play an important role in the motivation to use an AFO. © Arnold 2004.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Objective: Regaining walking ability is a major goal during the rehabilitation of stroke patients. To support this process an ankle-foot orthosis (AFC) is often prescribed. The aim of this study is to investigate the effect of an AFO on walking ability in chronic stroke patients. Design: Cross-over design with randomization for the interventions. Methods: Twenty chronic stroke patients, wearing an AFO for at least six months, were included. Walking ability was operationalized as comfortable walking speed, scores on the timed up and go (TUG) test and stairs test. Patients were measured with and without their AFO, the sequence of which was randomized. Additionally, subjective impressions of self-confidence and difficulty of the tasks were scored. Clinically relevant differences based on literature were defined for walking speed (20 cm/s), the TUG test (10 s). Gathered data were statistically analysed using a paired t-test. Results: The mean difference in favour of the AFO in walking speed was 4.8 cm/s (95% CI 0.85-8.7), in the TUG test 3.6 s (95% CI 2.4-4.8) and in the stairs test 8.6 s (95% CI 3.1-14.1). Sixty-five per cent of the patients experienced less difficulty and 70% of the patients felt more self-confident while wearing the AFO. Conclusions: The effect of an AFO on walking ability is statistically significant, but compared with the a priori defined differences it is too small to be clinically relevant. The effect on self-confidence suggests that other factors might play an important role in the motivation to use an AFO. © Arnold 2004.