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.
Darter, B. J.; Syrett, E. D.; Foreman, K. B.; Kubiak, E.; Sinclair, S.
In: PLoS ONE, Bd. 18, Nr. 2 February, 2023, ISSN: 1932-6203.
Abstract | Links | Schlagwörter: adult, amputation, article, Axtion, biomechanics, bone plate, cane, clinical article, frontal plane, gait, hip, hip adduction angle, hip angle, human, kinematics, limb prosthesis, male, middle aged, motion analysis system, Ossur Rheo, Ottobock C-Leg, Ottobock Genium, Ottobock X3, pelvic angle, pelvis lab angle, Pro-Flex Pivo, prosthesis implantation, radiographic parameter, Renegade XL, Rush Low Profile, Rush Renegade, software agent, torque, Triton, Triton Low Profile, trunk, trunk flexion angle, trunk lab angle, trunk pelvis angle, tyloxapol, unilateral transfemoral amputation, walker, walking speed, Wave Sport
@article{Darter2023,
title = {Changes in frontal plane kinematics over 12-months in individuals with the Percutaneous Osseointegrated Prosthesis (POP)},
author = {B. J. Darter and E. D. Syrett and K. B. Foreman and E. Kubiak and S. Sinclair},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2023020092&from=export},
doi = {10.1371/journal.pone.0281339},
issn = {1932-6203},
year = {2023},
date = {2023-01-01},
journal = {PLoS ONE},
volume = {18},
number = {2 February},
address = {B.J. Darter, Department of Physical Therapy, Virginia Commonwealth University, Richmond, VA, United States},
abstract = {Background A bone-anchored prosthesis (BAP) eliminates the need for a conventional socket by attaching a prosthesis directly to the user's skeleton. Currently, limited research addresses changes in gait mechanics post BAP implantation. Objective Examine changes in frontal plane movement patterns after BAP implantation. Methods Participants were individuals with unilateral transfemoral amputation (TFA) enrolled in the US Food and Drug Administration (FDA) Early Feasibility Study examining the Percutaneous Osseointegrated Prosthesis (POP). The participants completed overground gait assessments using their conventional socket and at 6-weeks, 12-weeks, 6-months, and 12- months following POP implantation. Statistical parameter mapping techniques were used in examining changes in frontal plane kinematics over the 12-months and differences with reference values for individuals without limb loss. Results Statistically significant deviations were found pre-implantation compared to reference values for hip and trunk angles during prosthetic limb stance phase, and for pelvis and trunk relative to the pelvis angles during prosthetic limb swing. At 6-weeks post-implantation, only the trunk angle demonstrated a statistically significant reduction in the percent of gait cycle with deviations relative to reference values. At 12-months post-implantation, results revealed frontal plane movements were no longer statistically different across the gait cycle for the trunk angle compared to reference values, and less of the gait cycle was statistically different compared to reference values for all other frontal plane patterns analyzed. No statistically significant within-participant differences were found for frontal plane movement patterns between pre-implantation and 6-weeks or 12-months post-implantation. Conclusions Deviations from reference values displayed prior to device implantation were reduced or eliminated 12-months post-implantation in all frontal plane patterns analyzed, while withinparticipant changes over the 12-month period did not reach statistical significance. Overall, the results suggest the transition to a BAP aided in normalizing gait patterns in a sample of relatively high functioning individuals with TFA.},
keywords = {adult, amputation, article, Axtion, biomechanics, bone plate, cane, clinical article, frontal plane, gait, hip, hip adduction angle, hip angle, human, kinematics, limb prosthesis, male, middle aged, motion analysis system, Ossur Rheo, Ottobock C-Leg, Ottobock Genium, Ottobock X3, pelvic angle, pelvis lab angle, Pro-Flex Pivo, prosthesis implantation, radiographic parameter, Renegade XL, Rush Low Profile, Rush Renegade, software agent, torque, Triton, Triton Low Profile, trunk, trunk flexion angle, trunk lab angle, trunk pelvis angle, tyloxapol, unilateral transfemoral amputation, walker, walking speed, Wave Sport},
pubstate = {published},
tppubtype = {article}
}
Background A bone-anchored prosthesis (BAP) eliminates the need for a conventional socket by attaching a prosthesis directly to the user's skeleton. Currently, limited research addresses changes in gait mechanics post BAP implantation. Objective Examine changes in frontal plane movement patterns after BAP implantation. Methods Participants were individuals with unilateral transfemoral amputation (TFA) enrolled in the US Food and Drug Administration (FDA) Early Feasibility Study examining the Percutaneous Osseointegrated Prosthesis (POP). The participants completed overground gait assessments using their conventional socket and at 6-weeks, 12-weeks, 6-months, and 12- months following POP implantation. Statistical parameter mapping techniques were used in examining changes in frontal plane kinematics over the 12-months and differences with reference values for individuals without limb loss. Results Statistically significant deviations were found pre-implantation compared to reference values for hip and trunk angles during prosthetic limb stance phase, and for pelvis and trunk relative to the pelvis angles during prosthetic limb swing. At 6-weeks post-implantation, only the trunk angle demonstrated a statistically significant reduction in the percent of gait cycle with deviations relative to reference values. At 12-months post-implantation, results revealed frontal plane movements were no longer statistically different across the gait cycle for the trunk angle compared to reference values, and less of the gait cycle was statistically different compared to reference values for all other frontal plane patterns analyzed. No statistically significant within-participant differences were found for frontal plane movement patterns between pre-implantation and 6-weeks or 12-months post-implantation. Conclusions Deviations from reference values displayed prior to device implantation were reduced or eliminated 12-months post-implantation in all frontal plane patterns analyzed, while withinparticipant changes over the 12-month period did not reach statistical significance. Overall, the results suggest the transition to a BAP aided in normalizing gait patterns in a sample of relatively high functioning individuals with TFA.
3.
Ernst, M.; Altenburg, B.; Schmalz, T.; Kannenberg, A.; Bellmann, M.
Benefits of a microprocessor-controlled prosthetic foot for ascending and descending slopes Artikel
In: J. NeuroEng. Rehabil., Bd. 19, Nr. 1, 2022, ISSN: 1743-0003.
Abstract | Links | Schlagwörter: adult, aged, article, biomechanics, clinical article, controlled study, effect size, foot prosthesis, human, kinematics, knee function, leg amputation, microprocessor, middle aged, motion analysis system, patient participation, range of motion, slope factor, transfemoral amputation, transtibial amputation, walking
@article{Ernst2022,
title = {Benefits of a microprocessor-controlled prosthetic foot for ascending and descending slopes},
author = {M. Ernst and B. Altenburg and T. Schmalz and A. Kannenberg and M. Bellmann},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2014862458&from=export},
doi = {10.1186/s12984-022-00983-y},
issn = {1743-0003},
year = {2022},
date = {2022-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {19},
number = {1},
address = {M. Ernst, Research Biomechanics, CR&S, Ottobock SE & Co. KGaA, Göttingen, Germany},
abstract = {Background: Prosthetic feet are prescribed for persons with a lower-limb amputation to restore lost mobility. However, due to limited adaptability of their ankles and springs, situations like walking on slopes or uneven ground remain challenging. This study investigated to what extent a microprocessor-controlled prosthetic foot (MPF) facilitates walking on slopes. Methods: Seven persons each with a unilateral transtibial amputation (TTA) and unilateral transfemoral amputation (TFA) as well as ten able-bodied subjects participated. Participants were studied while using a MPF and their prescribed standard feet with fixed ankle attachments. The study investigated ascending and descending a 10° slope. Kinematic and kinetic data were recorded with a motion capture system. Biomechanical parameters, in particular leg joint angles, shank orientation and external joint moments of the prosthetics side were calculated. Results: Prosthetic feet- and subject group-dependent joint angle and moment characteristics were observed for both situations. The MPF showed a larger and situation-dependent ankle range of motion compared to the standard feet. Furthermore, it remained in a dorsiflexed position during swing. While ascending, the MPF adapted the dorsiflexion moment and reduced the knee extension moment. At vertical shank orientation, it reduced the knee extension moment by 26% for TFA and 49% for TTA compared to the standard feet. For descending, differences between feet in the biomechanical knee characteristics were found for the TTA group, but not for the TFA group. At the vertical shank angle during slope descent, TTA demonstrated a behavior of the ankle moment similar to able-bodied controls when using the MPF. Conclusions: The studied MPF facilitated walking on slopes by adapting instantaneously to inclinations and, thus, easing the forward rotation of the leg over the prosthetic foot compared to standard feet with a fixed ankle attachment with amputation-level dependent effect sizes. It assumed a dorsiflexed ankle angle during swing, enabled a larger ankle range of motion and reduced the moments acting on the residual knee of TTA compared to the prescribed prosthetic standard feet. For individuals with TFA, the prosthetic knee joint seems to play a more crucial role for walking on ramps than the foot.},
keywords = {adult, aged, article, biomechanics, clinical article, controlled study, effect size, foot prosthesis, human, kinematics, knee function, leg amputation, microprocessor, middle aged, motion analysis system, patient participation, range of motion, slope factor, transfemoral amputation, transtibial amputation, walking},
pubstate = {published},
tppubtype = {article}
}
Background: Prosthetic feet are prescribed for persons with a lower-limb amputation to restore lost mobility. However, due to limited adaptability of their ankles and springs, situations like walking on slopes or uneven ground remain challenging. This study investigated to what extent a microprocessor-controlled prosthetic foot (MPF) facilitates walking on slopes. Methods: Seven persons each with a unilateral transtibial amputation (TTA) and unilateral transfemoral amputation (TFA) as well as ten able-bodied subjects participated. Participants were studied while using a MPF and their prescribed standard feet with fixed ankle attachments. The study investigated ascending and descending a 10° slope. Kinematic and kinetic data were recorded with a motion capture system. Biomechanical parameters, in particular leg joint angles, shank orientation and external joint moments of the prosthetics side were calculated. Results: Prosthetic feet- and subject group-dependent joint angle and moment characteristics were observed for both situations. The MPF showed a larger and situation-dependent ankle range of motion compared to the standard feet. Furthermore, it remained in a dorsiflexed position during swing. While ascending, the MPF adapted the dorsiflexion moment and reduced the knee extension moment. At vertical shank orientation, it reduced the knee extension moment by 26% for TFA and 49% for TTA compared to the standard feet. For descending, differences between feet in the biomechanical knee characteristics were found for the TTA group, but not for the TFA group. At the vertical shank angle during slope descent, TTA demonstrated a behavior of the ankle moment similar to able-bodied controls when using the MPF. Conclusions: The studied MPF facilitated walking on slopes by adapting instantaneously to inclinations and, thus, easing the forward rotation of the leg over the prosthetic foot compared to standard feet with a fixed ankle attachment with amputation-level dependent effect sizes. It assumed a dorsiflexed ankle angle during swing, enabled a larger ankle range of motion and reduced the moments acting on the residual knee of TTA compared to the prescribed prosthetic standard feet. For individuals with TFA, the prosthetic knee joint seems to play a more crucial role for walking on ramps than the foot.
4.
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.
5.
Ernst, M.; Altenburg, B.; Schmalz, T.
Characterizing adaptations of prosthetic feet in the frontal plane Artikel
In: Prosthet. Orthot. Int., Bd. 44, Nr. 4, S. 225–233, 2020, ISSN: 0309-3646.
Abstract | Links | Schlagwörter: arm prosthesis, arthrodesis, article, Axtion, biomechanics, bone conduction, finite element analysis, forefoot, histology, human, joint function, mathematical model, motion analysis system, osteoarthritis, Pacifica LP, Pro Flex LP, Prototype ESRJ, subtalar joint, theoretical model, Triton LP
@article{Ernst2020,
title = {Characterizing adaptations of prosthetic feet in the frontal plane},
author = {M. Ernst and B. Altenburg and T. Schmalz},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2005154580&from=export},
doi = {10.1177/0309364620917838},
issn = {0309-3646},
year = {2020},
date = {2020-01-01},
journal = {Prosthet. Orthot. Int.},
volume = {44},
number = {4},
pages = {225–233},
address = {M. Ernst, Research Biomechanics, Clinical Research and Services, Ottobock SE Co. KGaA, Göttingen, Germany},
abstract = {Background: Energy-storage and return feet incorporate various design features including split toes. As a potential improvement, an energy-storage and return foot with a dedicated ankle joint was recently introduced allowing for easily accessible inversion/eversion movement. However, the adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters have not been investigated in detail. Objectives: To investigate the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Study design: Mechanical testing and characterization. Methods: Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations is proposed. Results: The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all feet. Conclusions: The ability of prosthetic feet to adapt to uneven ground is design-dependent. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies. Clinical relevance: Knowing foot-specific ability to adapt to uneven ground may help in selecting an appropriate prosthetic foot for persons with a lower limb amputation. Faster and more comprehensive adaptations to uneven ground may lower the need for compensations and therefore increase user safety.},
keywords = {arm prosthesis, arthrodesis, article, Axtion, biomechanics, bone conduction, finite element analysis, forefoot, histology, human, joint function, mathematical model, motion analysis system, osteoarthritis, Pacifica LP, Pro Flex LP, Prototype ESRJ, subtalar joint, theoretical model, Triton LP},
pubstate = {published},
tppubtype = {article}
}
Background: Energy-storage and return feet incorporate various design features including split toes. As a potential improvement, an energy-storage and return foot with a dedicated ankle joint was recently introduced allowing for easily accessible inversion/eversion movement. However, the adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters have not been investigated in detail. Objectives: To investigate the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Study design: Mechanical testing and characterization. Methods: Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations is proposed. Results: The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all feet. Conclusions: The ability of prosthetic feet to adapt to uneven ground is design-dependent. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies. Clinical relevance: Knowing foot-specific ability to adapt to uneven ground may help in selecting an appropriate prosthetic foot for persons with a lower limb amputation. Faster and more comprehensive adaptations to uneven ground may lower the need for compensations and therefore increase user safety.
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.
Darter, B. J.; Syrett, E. D.; Foreman, K. B.; Kubiak, E.; Sinclair, S.
In: PLoS ONE, Bd. 18, Nr. 2 February, 2023, ISSN: 1932-6203.
Abstract | Links | Schlagwörter: adult, amputation, article, Axtion, biomechanics, bone plate, cane, clinical article, frontal plane, gait, hip, hip adduction angle, hip angle, human, kinematics, limb prosthesis, male, middle aged, motion analysis system, Ossur Rheo, Ottobock C-Leg, Ottobock Genium, Ottobock X3, pelvic angle, pelvis lab angle, Pro-Flex Pivo, prosthesis implantation, radiographic parameter, Renegade XL, Rush Low Profile, Rush Renegade, software agent, torque, Triton, Triton Low Profile, trunk, trunk flexion angle, trunk lab angle, trunk pelvis angle, tyloxapol, unilateral transfemoral amputation, walker, walking speed, Wave Sport
@article{Darter2023,
title = {Changes in frontal plane kinematics over 12-months in individuals with the Percutaneous Osseointegrated Prosthesis (POP)},
author = {B. J. Darter and E. D. Syrett and K. B. Foreman and E. Kubiak and S. Sinclair},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2023020092&from=export},
doi = {10.1371/journal.pone.0281339},
issn = {1932-6203},
year = {2023},
date = {2023-01-01},
journal = {PLoS ONE},
volume = {18},
number = {2 February},
address = {B.J. Darter, Department of Physical Therapy, Virginia Commonwealth University, Richmond, VA, United States},
abstract = {Background A bone-anchored prosthesis (BAP) eliminates the need for a conventional socket by attaching a prosthesis directly to the user's skeleton. Currently, limited research addresses changes in gait mechanics post BAP implantation. Objective Examine changes in frontal plane movement patterns after BAP implantation. Methods Participants were individuals with unilateral transfemoral amputation (TFA) enrolled in the US Food and Drug Administration (FDA) Early Feasibility Study examining the Percutaneous Osseointegrated Prosthesis (POP). The participants completed overground gait assessments using their conventional socket and at 6-weeks, 12-weeks, 6-months, and 12- months following POP implantation. Statistical parameter mapping techniques were used in examining changes in frontal plane kinematics over the 12-months and differences with reference values for individuals without limb loss. Results Statistically significant deviations were found pre-implantation compared to reference values for hip and trunk angles during prosthetic limb stance phase, and for pelvis and trunk relative to the pelvis angles during prosthetic limb swing. At 6-weeks post-implantation, only the trunk angle demonstrated a statistically significant reduction in the percent of gait cycle with deviations relative to reference values. At 12-months post-implantation, results revealed frontal plane movements were no longer statistically different across the gait cycle for the trunk angle compared to reference values, and less of the gait cycle was statistically different compared to reference values for all other frontal plane patterns analyzed. No statistically significant within-participant differences were found for frontal plane movement patterns between pre-implantation and 6-weeks or 12-months post-implantation. Conclusions Deviations from reference values displayed prior to device implantation were reduced or eliminated 12-months post-implantation in all frontal plane patterns analyzed, while withinparticipant changes over the 12-month period did not reach statistical significance. Overall, the results suggest the transition to a BAP aided in normalizing gait patterns in a sample of relatively high functioning individuals with TFA.},
keywords = {adult, amputation, article, Axtion, biomechanics, bone plate, cane, clinical article, frontal plane, gait, hip, hip adduction angle, hip angle, human, kinematics, limb prosthesis, male, middle aged, motion analysis system, Ossur Rheo, Ottobock C-Leg, Ottobock Genium, Ottobock X3, pelvic angle, pelvis lab angle, Pro-Flex Pivo, prosthesis implantation, radiographic parameter, Renegade XL, Rush Low Profile, Rush Renegade, software agent, torque, Triton, Triton Low Profile, trunk, trunk flexion angle, trunk lab angle, trunk pelvis angle, tyloxapol, unilateral transfemoral amputation, walker, walking speed, Wave Sport},
pubstate = {published},
tppubtype = {article}
}
Background A bone-anchored prosthesis (BAP) eliminates the need for a conventional socket by attaching a prosthesis directly to the user's skeleton. Currently, limited research addresses changes in gait mechanics post BAP implantation. Objective Examine changes in frontal plane movement patterns after BAP implantation. Methods Participants were individuals with unilateral transfemoral amputation (TFA) enrolled in the US Food and Drug Administration (FDA) Early Feasibility Study examining the Percutaneous Osseointegrated Prosthesis (POP). The participants completed overground gait assessments using their conventional socket and at 6-weeks, 12-weeks, 6-months, and 12- months following POP implantation. Statistical parameter mapping techniques were used in examining changes in frontal plane kinematics over the 12-months and differences with reference values for individuals without limb loss. Results Statistically significant deviations were found pre-implantation compared to reference values for hip and trunk angles during prosthetic limb stance phase, and for pelvis and trunk relative to the pelvis angles during prosthetic limb swing. At 6-weeks post-implantation, only the trunk angle demonstrated a statistically significant reduction in the percent of gait cycle with deviations relative to reference values. At 12-months post-implantation, results revealed frontal plane movements were no longer statistically different across the gait cycle for the trunk angle compared to reference values, and less of the gait cycle was statistically different compared to reference values for all other frontal plane patterns analyzed. No statistically significant within-participant differences were found for frontal plane movement patterns between pre-implantation and 6-weeks or 12-months post-implantation. Conclusions Deviations from reference values displayed prior to device implantation were reduced or eliminated 12-months post-implantation in all frontal plane patterns analyzed, while withinparticipant changes over the 12-month period did not reach statistical significance. Overall, the results suggest the transition to a BAP aided in normalizing gait patterns in a sample of relatively high functioning individuals with TFA.
2022
Ernst, M.; Altenburg, B.; Schmalz, T.; Kannenberg, A.; Bellmann, M.
Benefits of a microprocessor-controlled prosthetic foot for ascending and descending slopes Artikel
In: J. NeuroEng. Rehabil., Bd. 19, Nr. 1, 2022, ISSN: 1743-0003.
Abstract | Links | Schlagwörter: adult, aged, article, biomechanics, clinical article, controlled study, effect size, foot prosthesis, human, kinematics, knee function, leg amputation, microprocessor, middle aged, motion analysis system, patient participation, range of motion, slope factor, transfemoral amputation, transtibial amputation, walking
@article{Ernst2022,
title = {Benefits of a microprocessor-controlled prosthetic foot for ascending and descending slopes},
author = {M. Ernst and B. Altenburg and T. Schmalz and A. Kannenberg and M. Bellmann},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2014862458&from=export},
doi = {10.1186/s12984-022-00983-y},
issn = {1743-0003},
year = {2022},
date = {2022-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {19},
number = {1},
address = {M. Ernst, Research Biomechanics, CR&S, Ottobock SE & Co. KGaA, Göttingen, Germany},
abstract = {Background: Prosthetic feet are prescribed for persons with a lower-limb amputation to restore lost mobility. However, due to limited adaptability of their ankles and springs, situations like walking on slopes or uneven ground remain challenging. This study investigated to what extent a microprocessor-controlled prosthetic foot (MPF) facilitates walking on slopes. Methods: Seven persons each with a unilateral transtibial amputation (TTA) and unilateral transfemoral amputation (TFA) as well as ten able-bodied subjects participated. Participants were studied while using a MPF and their prescribed standard feet with fixed ankle attachments. The study investigated ascending and descending a 10° slope. Kinematic and kinetic data were recorded with a motion capture system. Biomechanical parameters, in particular leg joint angles, shank orientation and external joint moments of the prosthetics side were calculated. Results: Prosthetic feet- and subject group-dependent joint angle and moment characteristics were observed for both situations. The MPF showed a larger and situation-dependent ankle range of motion compared to the standard feet. Furthermore, it remained in a dorsiflexed position during swing. While ascending, the MPF adapted the dorsiflexion moment and reduced the knee extension moment. At vertical shank orientation, it reduced the knee extension moment by 26% for TFA and 49% for TTA compared to the standard feet. For descending, differences between feet in the biomechanical knee characteristics were found for the TTA group, but not for the TFA group. At the vertical shank angle during slope descent, TTA demonstrated a behavior of the ankle moment similar to able-bodied controls when using the MPF. Conclusions: The studied MPF facilitated walking on slopes by adapting instantaneously to inclinations and, thus, easing the forward rotation of the leg over the prosthetic foot compared to standard feet with a fixed ankle attachment with amputation-level dependent effect sizes. It assumed a dorsiflexed ankle angle during swing, enabled a larger ankle range of motion and reduced the moments acting on the residual knee of TTA compared to the prescribed prosthetic standard feet. For individuals with TFA, the prosthetic knee joint seems to play a more crucial role for walking on ramps than the foot.},
keywords = {adult, aged, article, biomechanics, clinical article, controlled study, effect size, foot prosthesis, human, kinematics, knee function, leg amputation, microprocessor, middle aged, motion analysis system, patient participation, range of motion, slope factor, transfemoral amputation, transtibial amputation, walking},
pubstate = {published},
tppubtype = {article}
}
Background: Prosthetic feet are prescribed for persons with a lower-limb amputation to restore lost mobility. However, due to limited adaptability of their ankles and springs, situations like walking on slopes or uneven ground remain challenging. This study investigated to what extent a microprocessor-controlled prosthetic foot (MPF) facilitates walking on slopes. Methods: Seven persons each with a unilateral transtibial amputation (TTA) and unilateral transfemoral amputation (TFA) as well as ten able-bodied subjects participated. Participants were studied while using a MPF and their prescribed standard feet with fixed ankle attachments. The study investigated ascending and descending a 10° slope. Kinematic and kinetic data were recorded with a motion capture system. Biomechanical parameters, in particular leg joint angles, shank orientation and external joint moments of the prosthetics side were calculated. Results: Prosthetic feet- and subject group-dependent joint angle and moment characteristics were observed for both situations. The MPF showed a larger and situation-dependent ankle range of motion compared to the standard feet. Furthermore, it remained in a dorsiflexed position during swing. While ascending, the MPF adapted the dorsiflexion moment and reduced the knee extension moment. At vertical shank orientation, it reduced the knee extension moment by 26% for TFA and 49% for TTA compared to the standard feet. For descending, differences between feet in the biomechanical knee characteristics were found for the TTA group, but not for the TFA group. At the vertical shank angle during slope descent, TTA demonstrated a behavior of the ankle moment similar to able-bodied controls when using the MPF. Conclusions: The studied MPF facilitated walking on slopes by adapting instantaneously to inclinations and, thus, easing the forward rotation of the leg over the prosthetic foot compared to standard feet with a fixed ankle attachment with amputation-level dependent effect sizes. It assumed a dorsiflexed ankle angle during swing, enabled a larger ankle range of motion and reduced the moments acting on the residual knee of TTA compared to the prescribed prosthetic standard feet. For individuals with TFA, the prosthetic knee joint seems to play a more crucial role for walking on ramps than the foot.
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.
2020
Ernst, M.; Altenburg, B.; Schmalz, T.
Characterizing adaptations of prosthetic feet in the frontal plane Artikel
In: Prosthet. Orthot. Int., Bd. 44, Nr. 4, S. 225–233, 2020, ISSN: 0309-3646.
Abstract | Links | Schlagwörter: arm prosthesis, arthrodesis, article, Axtion, biomechanics, bone conduction, finite element analysis, forefoot, histology, human, joint function, mathematical model, motion analysis system, osteoarthritis, Pacifica LP, Pro Flex LP, Prototype ESRJ, subtalar joint, theoretical model, Triton LP
@article{Ernst2020,
title = {Characterizing adaptations of prosthetic feet in the frontal plane},
author = {M. Ernst and B. Altenburg and T. Schmalz},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2005154580&from=export},
doi = {10.1177/0309364620917838},
issn = {0309-3646},
year = {2020},
date = {2020-01-01},
journal = {Prosthet. Orthot. Int.},
volume = {44},
number = {4},
pages = {225–233},
address = {M. Ernst, Research Biomechanics, Clinical Research and Services, Ottobock SE Co. KGaA, Göttingen, Germany},
abstract = {Background: Energy-storage and return feet incorporate various design features including split toes. As a potential improvement, an energy-storage and return foot with a dedicated ankle joint was recently introduced allowing for easily accessible inversion/eversion movement. However, the adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters have not been investigated in detail. Objectives: To investigate the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Study design: Mechanical testing and characterization. Methods: Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations is proposed. Results: The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all feet. Conclusions: The ability of prosthetic feet to adapt to uneven ground is design-dependent. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies. Clinical relevance: Knowing foot-specific ability to adapt to uneven ground may help in selecting an appropriate prosthetic foot for persons with a lower limb amputation. Faster and more comprehensive adaptations to uneven ground may lower the need for compensations and therefore increase user safety.},
keywords = {arm prosthesis, arthrodesis, article, Axtion, biomechanics, bone conduction, finite element analysis, forefoot, histology, human, joint function, mathematical model, motion analysis system, osteoarthritis, Pacifica LP, Pro Flex LP, Prototype ESRJ, subtalar joint, theoretical model, Triton LP},
pubstate = {published},
tppubtype = {article}
}
Background: Energy-storage and return feet incorporate various design features including split toes. As a potential improvement, an energy-storage and return foot with a dedicated ankle joint was recently introduced allowing for easily accessible inversion/eversion movement. However, the adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters have not been investigated in detail. Objectives: To investigate the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Study design: Mechanical testing and characterization. Methods: Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations is proposed. Results: The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all feet. Conclusions: The ability of prosthetic feet to adapt to uneven ground is design-dependent. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies. Clinical relevance: Knowing foot-specific ability to adapt to uneven ground may help in selecting an appropriate prosthetic foot for persons with a lower limb amputation. Faster and more comprehensive adaptations to uneven ground may lower the need for compensations and therefore increase user safety.
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.
Darter, B. J.; Syrett, E. D.; Foreman, K. B.; Kubiak, E.; Sinclair, S.
In: PLoS ONE, Bd. 18, Nr. 2 February, 2023, ISSN: 1932-6203.
@article{Darter2023,
title = {Changes in frontal plane kinematics over 12-months in individuals with the Percutaneous Osseointegrated Prosthesis (POP)},
author = {B. J. Darter and E. D. Syrett and K. B. Foreman and E. Kubiak and S. Sinclair},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2023020092&from=export},
doi = {10.1371/journal.pone.0281339},
issn = {1932-6203},
year = {2023},
date = {2023-01-01},
journal = {PLoS ONE},
volume = {18},
number = {2 February},
address = {B.J. Darter, Department of Physical Therapy, Virginia Commonwealth University, Richmond, VA, United States},
abstract = {Background A bone-anchored prosthesis (BAP) eliminates the need for a conventional socket by attaching a prosthesis directly to the user's skeleton. Currently, limited research addresses changes in gait mechanics post BAP implantation. Objective Examine changes in frontal plane movement patterns after BAP implantation. Methods Participants were individuals with unilateral transfemoral amputation (TFA) enrolled in the US Food and Drug Administration (FDA) Early Feasibility Study examining the Percutaneous Osseointegrated Prosthesis (POP). The participants completed overground gait assessments using their conventional socket and at 6-weeks, 12-weeks, 6-months, and 12- months following POP implantation. Statistical parameter mapping techniques were used in examining changes in frontal plane kinematics over the 12-months and differences with reference values for individuals without limb loss. Results Statistically significant deviations were found pre-implantation compared to reference values for hip and trunk angles during prosthetic limb stance phase, and for pelvis and trunk relative to the pelvis angles during prosthetic limb swing. At 6-weeks post-implantation, only the trunk angle demonstrated a statistically significant reduction in the percent of gait cycle with deviations relative to reference values. At 12-months post-implantation, results revealed frontal plane movements were no longer statistically different across the gait cycle for the trunk angle compared to reference values, and less of the gait cycle was statistically different compared to reference values for all other frontal plane patterns analyzed. No statistically significant within-participant differences were found for frontal plane movement patterns between pre-implantation and 6-weeks or 12-months post-implantation. Conclusions Deviations from reference values displayed prior to device implantation were reduced or eliminated 12-months post-implantation in all frontal plane patterns analyzed, while withinparticipant changes over the 12-month period did not reach statistical significance. Overall, the results suggest the transition to a BAP aided in normalizing gait patterns in a sample of relatively high functioning individuals with TFA.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background A bone-anchored prosthesis (BAP) eliminates the need for a conventional socket by attaching a prosthesis directly to the user's skeleton. Currently, limited research addresses changes in gait mechanics post BAP implantation. Objective Examine changes in frontal plane movement patterns after BAP implantation. Methods Participants were individuals with unilateral transfemoral amputation (TFA) enrolled in the US Food and Drug Administration (FDA) Early Feasibility Study examining the Percutaneous Osseointegrated Prosthesis (POP). The participants completed overground gait assessments using their conventional socket and at 6-weeks, 12-weeks, 6-months, and 12- months following POP implantation. Statistical parameter mapping techniques were used in examining changes in frontal plane kinematics over the 12-months and differences with reference values for individuals without limb loss. Results Statistically significant deviations were found pre-implantation compared to reference values for hip and trunk angles during prosthetic limb stance phase, and for pelvis and trunk relative to the pelvis angles during prosthetic limb swing. At 6-weeks post-implantation, only the trunk angle demonstrated a statistically significant reduction in the percent of gait cycle with deviations relative to reference values. At 12-months post-implantation, results revealed frontal plane movements were no longer statistically different across the gait cycle for the trunk angle compared to reference values, and less of the gait cycle was statistically different compared to reference values for all other frontal plane patterns analyzed. No statistically significant within-participant differences were found for frontal plane movement patterns between pre-implantation and 6-weeks or 12-months post-implantation. Conclusions Deviations from reference values displayed prior to device implantation were reduced or eliminated 12-months post-implantation in all frontal plane patterns analyzed, while withinparticipant changes over the 12-month period did not reach statistical significance. Overall, the results suggest the transition to a BAP aided in normalizing gait patterns in a sample of relatively high functioning individuals with TFA.
2022
Ernst, M.; Altenburg, B.; Schmalz, T.; Kannenberg, A.; Bellmann, M.
Benefits of a microprocessor-controlled prosthetic foot for ascending and descending slopes Artikel
In: J. NeuroEng. Rehabil., Bd. 19, Nr. 1, 2022, ISSN: 1743-0003.
@article{Ernst2022,
title = {Benefits of a microprocessor-controlled prosthetic foot for ascending and descending slopes},
author = {M. Ernst and B. Altenburg and T. Schmalz and A. Kannenberg and M. Bellmann},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2014862458&from=export},
doi = {10.1186/s12984-022-00983-y},
issn = {1743-0003},
year = {2022},
date = {2022-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {19},
number = {1},
address = {M. Ernst, Research Biomechanics, CR&S, Ottobock SE & Co. KGaA, Göttingen, Germany},
abstract = {Background: Prosthetic feet are prescribed for persons with a lower-limb amputation to restore lost mobility. However, due to limited adaptability of their ankles and springs, situations like walking on slopes or uneven ground remain challenging. This study investigated to what extent a microprocessor-controlled prosthetic foot (MPF) facilitates walking on slopes. Methods: Seven persons each with a unilateral transtibial amputation (TTA) and unilateral transfemoral amputation (TFA) as well as ten able-bodied subjects participated. Participants were studied while using a MPF and their prescribed standard feet with fixed ankle attachments. The study investigated ascending and descending a 10° slope. Kinematic and kinetic data were recorded with a motion capture system. Biomechanical parameters, in particular leg joint angles, shank orientation and external joint moments of the prosthetics side were calculated. Results: Prosthetic feet- and subject group-dependent joint angle and moment characteristics were observed for both situations. The MPF showed a larger and situation-dependent ankle range of motion compared to the standard feet. Furthermore, it remained in a dorsiflexed position during swing. While ascending, the MPF adapted the dorsiflexion moment and reduced the knee extension moment. At vertical shank orientation, it reduced the knee extension moment by 26% for TFA and 49% for TTA compared to the standard feet. For descending, differences between feet in the biomechanical knee characteristics were found for the TTA group, but not for the TFA group. At the vertical shank angle during slope descent, TTA demonstrated a behavior of the ankle moment similar to able-bodied controls when using the MPF. Conclusions: The studied MPF facilitated walking on slopes by adapting instantaneously to inclinations and, thus, easing the forward rotation of the leg over the prosthetic foot compared to standard feet with a fixed ankle attachment with amputation-level dependent effect sizes. It assumed a dorsiflexed ankle angle during swing, enabled a larger ankle range of motion and reduced the moments acting on the residual knee of TTA compared to the prescribed prosthetic standard feet. For individuals with TFA, the prosthetic knee joint seems to play a more crucial role for walking on ramps than the foot.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: Prosthetic feet are prescribed for persons with a lower-limb amputation to restore lost mobility. However, due to limited adaptability of their ankles and springs, situations like walking on slopes or uneven ground remain challenging. This study investigated to what extent a microprocessor-controlled prosthetic foot (MPF) facilitates walking on slopes. Methods: Seven persons each with a unilateral transtibial amputation (TTA) and unilateral transfemoral amputation (TFA) as well as ten able-bodied subjects participated. Participants were studied while using a MPF and their prescribed standard feet with fixed ankle attachments. The study investigated ascending and descending a 10° slope. Kinematic and kinetic data were recorded with a motion capture system. Biomechanical parameters, in particular leg joint angles, shank orientation and external joint moments of the prosthetics side were calculated. Results: Prosthetic feet- and subject group-dependent joint angle and moment characteristics were observed for both situations. The MPF showed a larger and situation-dependent ankle range of motion compared to the standard feet. Furthermore, it remained in a dorsiflexed position during swing. While ascending, the MPF adapted the dorsiflexion moment and reduced the knee extension moment. At vertical shank orientation, it reduced the knee extension moment by 26% for TFA and 49% for TTA compared to the standard feet. For descending, differences between feet in the biomechanical knee characteristics were found for the TTA group, but not for the TFA group. At the vertical shank angle during slope descent, TTA demonstrated a behavior of the ankle moment similar to able-bodied controls when using the MPF. Conclusions: The studied MPF facilitated walking on slopes by adapting instantaneously to inclinations and, thus, easing the forward rotation of the leg over the prosthetic foot compared to standard feet with a fixed ankle attachment with amputation-level dependent effect sizes. It assumed a dorsiflexed ankle angle during swing, enabled a larger ankle range of motion and reduced the moments acting on the residual knee of TTA compared to the prescribed prosthetic standard feet. For individuals with TFA, the prosthetic knee joint seems to play a more crucial role for walking on ramps than the foot.
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.
2020
Ernst, M.; Altenburg, B.; Schmalz, T.
Characterizing adaptations of prosthetic feet in the frontal plane Artikel
In: Prosthet. Orthot. Int., Bd. 44, Nr. 4, S. 225–233, 2020, ISSN: 0309-3646.
@article{Ernst2020,
title = {Characterizing adaptations of prosthetic feet in the frontal plane},
author = {M. Ernst and B. Altenburg and T. Schmalz},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2005154580&from=export},
doi = {10.1177/0309364620917838},
issn = {0309-3646},
year = {2020},
date = {2020-01-01},
journal = {Prosthet. Orthot. Int.},
volume = {44},
number = {4},
pages = {225–233},
address = {M. Ernst, Research Biomechanics, Clinical Research and Services, Ottobock SE Co. KGaA, Göttingen, Germany},
abstract = {Background: Energy-storage and return feet incorporate various design features including split toes. As a potential improvement, an energy-storage and return foot with a dedicated ankle joint was recently introduced allowing for easily accessible inversion/eversion movement. However, the adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters have not been investigated in detail. Objectives: To investigate the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Study design: Mechanical testing and characterization. Methods: Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations is proposed. Results: The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all feet. Conclusions: The ability of prosthetic feet to adapt to uneven ground is design-dependent. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies. Clinical relevance: Knowing foot-specific ability to adapt to uneven ground may help in selecting an appropriate prosthetic foot for persons with a lower limb amputation. Faster and more comprehensive adaptations to uneven ground may lower the need for compensations and therefore increase user safety.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: Energy-storage and return feet incorporate various design features including split toes. As a potential improvement, an energy-storage and return foot with a dedicated ankle joint was recently introduced allowing for easily accessible inversion/eversion movement. However, the adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters have not been investigated in detail. Objectives: To investigate the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Study design: Mechanical testing and characterization. Methods: Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations is proposed. Results: The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all feet. Conclusions: The ability of prosthetic feet to adapt to uneven ground is design-dependent. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies. Clinical relevance: Knowing foot-specific ability to adapt to uneven ground may help in selecting an appropriate prosthetic foot for persons with a lower limb amputation. Faster and more comprehensive adaptations to uneven ground may lower the need for compensations and therefore increase user safety.
Taboga, P.; Beck, O. N.; Grabowski, A. M.
In: PLoS ONE, Bd. 15, Nr. 2, 2020, ISSN: 1932-6203.
@article{Taboga2020,
title = {Prosthetic shape, but not stiffness or height, affects the maximum speed of sprinters with bilateral transtibial amputations},
author = {P. Taboga and O. N. Beck and A. M. Grabowski},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L2005026109&from=export},
doi = {10.1371/journal.pone.0229035},
issn = {1932-6203},
year = {2020},
date = {2020-01-01},
journal = {PLoS ONE},
volume = {15},
number = {2},
address = {P. Taboga, Department of Kinesiology, California State University, Sacramento, CA, United States},
abstract = {Running-specific prostheses (RSPs) have facilitated an athlete with bilateral transtibial amputations to compete in the Olympic Games. However, the performance effects of using RSPs compared to biological legs remains controversial. Further, the use of different prosthetic configurations such as shape, stiffness, and height likely influence performance. We determined the effects of using 15 different RSP configurations on the maximum speed of five male athletes with bilateral transtibial amputations. These athletes performed sets of running trials up to maximum speed using three different RSP models (Freedom Innovations Catapult FX6, Össur Flex-Foot Cheetah Xtend and Ottobock 1E90 Sprinter) each with five combinations of stiffness category and height. We measured ground reaction forces during each maximum speed trial to determine the biomechanical parameters associated with different RSP configurations and maximum sprinting speeds. Use of the J-shaped Cheetah Xtend and 1E90 Sprinter RSPs resulted in 8.3% and 8.0% (p<0.001) faster maximum speeds compared to the use of the C-shaped Catapult FX6 RSPs, respectively. Neither RSP stiffness expressed as a category (p = 0.836) nor as kNm-1 (p = 0.916) affected maximum speed. Further, prosthetic height had no effect on maximum speed (p = 0.762). Faster maximum speeds were associated with reduced ground contact time, aerial time, and overall leg stiffness, as well as with greater stance-average vertical ground reaction force, contact length, and vertical stiffness (p = 0.015 for aerial time, p<0.001 for all other variables). RSP shape, but not stiffness or height, influences the maximum speed of athletes with bilateral transtibial amputations.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Running-specific prostheses (RSPs) have facilitated an athlete with bilateral transtibial amputations to compete in the Olympic Games. However, the performance effects of using RSPs compared to biological legs remains controversial. Further, the use of different prosthetic configurations such as shape, stiffness, and height likely influence performance. We determined the effects of using 15 different RSP configurations on the maximum speed of five male athletes with bilateral transtibial amputations. These athletes performed sets of running trials up to maximum speed using three different RSP models (Freedom Innovations Catapult FX6, Össur Flex-Foot Cheetah Xtend and Ottobock 1E90 Sprinter) each with five combinations of stiffness category and height. We measured ground reaction forces during each maximum speed trial to determine the biomechanical parameters associated with different RSP configurations and maximum sprinting speeds. Use of the J-shaped Cheetah Xtend and 1E90 Sprinter RSPs resulted in 8.3% and 8.0% (p<0.001) faster maximum speeds compared to the use of the C-shaped Catapult FX6 RSPs, respectively. Neither RSP stiffness expressed as a category (p = 0.836) nor as kNm-1 (p = 0.916) affected maximum speed. Further, prosthetic height had no effect on maximum speed (p = 0.762). Faster maximum speeds were associated with reduced ground contact time, aerial time, and overall leg stiffness, as well as with greater stance-average vertical ground reaction force, contact length, and vertical stiffness (p = 0.015 for aerial time, p<0.001 for all other variables). RSP shape, but not stiffness or height, influences the maximum speed of athletes with bilateral transtibial amputations.
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.
2018
Houdijk, H.; Wezenberg, D.; Hak, L.; Cutti, A. G.
In: J. NeuroEng. Rehabil., Bd. 15, 2018, ISSN: 1743-0003.
@article{Houdijk2018,
title = {Energy storing and return prosthetic feet improve step length symmetry while preserving margins of stability in persons with transtibial amputation},
author = {H. Houdijk and D. Wezenberg and L. Hak and A. G. Cutti},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L623754871&from=export},
doi = {10.1186/s12984-018-0404-9},
issn = {1743-0003},
year = {2018},
date = {2018-01-01},
journal = {J. NeuroEng. Rehabil.},
volume = {15},
address = {H. Houdijk, Department of Human Movement Sciences, Faculty of Behavioral and Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorststraat 9, Amsterdam, Netherlands},
abstract = {Background: Energy storing and return (ESAR) feet are generally preferred over solid ankle cushioned heel (SACH) feet by people with a lower limb amputation. While ESAR feet have been shown to have only limited effect on gait economy, other functional benefits should account for this preference. A simple biomechanical model suggests that enhanced gait stability and gait symmetry could prove to explain part of the difference in the subjective preference between both feet. Aim: To investigate whether increased push-off power with ESAR feet increases center of mass velocity at push off and enhance intact step length and step length symmetry while preserving the margin of stability during walking in people with a transtibial prosthesis. Methods: Fifteen people with a unilateral transtibial amputation walked with their prescribed ESAR foot and a SACH foot at a fixed walking speed (1.2 m/s) over a level walkway while kinematic and kinetic data were collected. Push-off work generated by the foot, center of mass velocity, step length, step length symmetry and backward margin of stability were assessed and compared between feet. Results: Push-off work was significantly higher when using the ESAR foot compared to the SACH foot. Simultaneously, center of mass velocity at toe-off was higher with ESAR compared to SACH, and intact step length and step length symmetry increased without reducing the backward margin of stability. Conclusion: Compared to the SACH foot, the ESAR foot allowed an improvement of step length symmetry while preserving the backward margin of stability at community ambulation speed. These benefits may possibly contribute to the subjective preference for ESAR feet in people with a lower limb amputation.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Background: Energy storing and return (ESAR) feet are generally preferred over solid ankle cushioned heel (SACH) feet by people with a lower limb amputation. While ESAR feet have been shown to have only limited effect on gait economy, other functional benefits should account for this preference. A simple biomechanical model suggests that enhanced gait stability and gait symmetry could prove to explain part of the difference in the subjective preference between both feet. Aim: To investigate whether increased push-off power with ESAR feet increases center of mass velocity at push off and enhance intact step length and step length symmetry while preserving the margin of stability during walking in people with a transtibial prosthesis. Methods: Fifteen people with a unilateral transtibial amputation walked with their prescribed ESAR foot and a SACH foot at a fixed walking speed (1.2 m/s) over a level walkway while kinematic and kinetic data were collected. Push-off work generated by the foot, center of mass velocity, step length, step length symmetry and backward margin of stability were assessed and compared between feet. Results: Push-off work was significantly higher when using the ESAR foot compared to the SACH foot. Simultaneously, center of mass velocity at toe-off was higher with ESAR compared to SACH, and intact step length and step length symmetry increased without reducing the backward margin of stability. Conclusion: Compared to the SACH foot, the ESAR foot allowed an improvement of step length symmetry while preserving the backward margin of stability at community ambulation speed. These benefits may possibly contribute to the subjective preference for ESAR feet in people with a lower limb amputation.
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.
2016
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.
2014
Kistenberg, R. S.
Prosthetic choices for people with leg and arm amputations Artikel
In: Phys. Med. Rehabil. Clin. North Am., Bd. 25, Nr. 1, S. 93–115, 2014, ISSN: 1558-1381.
@article{Kistenberg2014,
title = {Prosthetic choices for people with leg and arm amputations},
author = {R. S. Kistenberg},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L370343297&from=export},
doi = {10.1016/j.pmr.2013.10.001},
issn = {1558-1381},
year = {2014},
date = {2014-01-01},
journal = {Phys. Med. Rehabil. Clin. North Am.},
volume = {25},
number = {1},
pages = {93–115},
address = {R.S. Kistenberg, Georgia Institute of Technology, School of Applied Physiology, 555 14th Street, Atlanta, GA 30318, United States},
abstract = {New technology and materials have advanced prosthetic designs to enable people who rely on artificial limbs to achieve feats never dreamed before. However, the latest and the greatest technology is not appropriate for everyone. The aim of this article is to present contemporary options that are available for people who rely on artificial limbs to enhance their quality of life for mobility and independence. © 2014 Elsevier Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
New technology and materials have advanced prosthetic designs to enable people who rely on artificial limbs to achieve feats never dreamed before. However, the latest and the greatest technology is not appropriate for everyone. The aim of this article is to present contemporary options that are available for people who rely on artificial limbs to enhance their quality of life for mobility and independence. © 2014 Elsevier Inc.
2012
Portnoy, S.; Kristal, A.; Gefen, A.; Siev-Ner, I.
In: Gait Posture, Bd. 35, Nr. 1, S. 121–125, 2012, ISSN: 1879-2219.
@article{Portnoy2012,
title = {Outdoor dynamic subject-specific evaluation of internal stresses in the residual limb: Hydraulic energy-stored prosthetic foot compared to conventional energy-stored prosthetic feet},
author = {S. Portnoy and A. Kristal and A. Gefen and I. Siev-Ner},
url = {https://www.embase.com/search/results?subaction=viewrecord&id=L51635905&from=export},
doi = {10.1016/j.gaitpost.2011.08.021},
issn = {1879-2219},
year = {2012},
date = {2012-01-01},
journal = {Gait Posture},
volume = {35},
number = {1},
pages = {121–125},
address = {S. Portnoy, Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel},
abstract = {The prosthetic foot plays an important role in propelling, breaking, balancing and supporting body loads while the amputee ambulates on different grounds. It is therefore important to quantify the effect of the prosthetic foot mechanism on biomechanical parameters, in order to prevent pressure ulcers and deep tissue injury. Our aim was to monitor the internal stresses in the residuum of transtibial amputation (TTA) prosthetic-users ambulating on different terrains, which the amputees encounter during their daily activities, i.e. paved floor, grass, ascending and descending stairs and slope. We specifically aimed to compare between the internal stresses in the TTA residuum of amputees ambulating with a novel hydraulic prosthetic foot compared to conventional energy storage and return (ESR) prosthetic feet. Monitoring of internal stresses was accomplished using a portable subject-specific real-time internal stress monitor. We found significant decrease (p<. 0.01) in peak internal stresses and in the loading rate of the amputated limb, while walking with the hydraulic foot, compared to walking with ESR feet. The loading rate calculated while ambulating with the hydraulic foot was at least three times lower than the loading rate calculated while ambulating with the ESR foot. Although the average decrease in internal stresses was ∼2-fold larger when replacing single-toe ESR feet with the hydraulic foot than when replacing split-toed ESR feet with the hydraulic foot, the differences were statistically insignificant. Our findings suggest that using a hydraulic prosthetic foot may protect the distal tibial end of the TTA residuum from high stresses, therefore preventing pressure-related injury and pain. © 2011 Elsevier B.V.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The prosthetic foot plays an important role in propelling, breaking, balancing and supporting body loads while the amputee ambulates on different grounds. It is therefore important to quantify the effect of the prosthetic foot mechanism on biomechanical parameters, in order to prevent pressure ulcers and deep tissue injury. Our aim was to monitor the internal stresses in the residuum of transtibial amputation (TTA) prosthetic-users ambulating on different terrains, which the amputees encounter during their daily activities, i.e. paved floor, grass, ascending and descending stairs and slope. We specifically aimed to compare between the internal stresses in the TTA residuum of amputees ambulating with a novel hydraulic prosthetic foot compared to conventional energy storage and return (ESR) prosthetic feet. Monitoring of internal stresses was accomplished using a portable subject-specific real-time internal stress monitor. We found significant decrease (p<. 0.01) in peak internal stresses and in the loading rate of the amputated limb, while walking with the hydraulic foot, compared to walking with ESR feet. The loading rate calculated while ambulating with the hydraulic foot was at least three times lower than the loading rate calculated while ambulating with the ESR foot. Although the average decrease in internal stresses was ∼2-fold larger when replacing single-toe ESR feet with the hydraulic foot than when replacing split-toed ESR feet with the hydraulic foot, the differences were statistically insignificant. Our findings suggest that using a hydraulic prosthetic foot may protect the distal tibial end of the TTA residuum from high stresses, therefore preventing pressure-related injury and pain. © 2011 Elsevier B.V.
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.