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Jonathan Kofman - One of the best experts on this subject based on the ideXlab platform.
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preliminary kinematic evaluation of a new stance control knee ankle foot Orthosis
Clinical Biomechanics, 2006Co-Authors: Terris Yakimovich, Jonathan Kofman, Edward D. LemaireAbstract:Abstract Background Stance-control knee–ankle–foot orthoses permit free knee motion in swing while providing knee flexion resistance in stance for individuals with quadriceps muscle weakness. However, some stance-control knee–ankle–foot orthoses require full knee extension to engage the knee-joint lock, thereby not providing knee support when climbing stairs or stepping over curbs. Stance-control knee–ankle–foot orthoses that do support a flexed knee are either heavy, bulky, expensive, offer a limited number of locking positions, or cause noise. This paper presents a preliminary kinematic evaluation of a new stance-control knee–ankle–foot Orthosis that was designed to address these limitations. Methods Kinematic gait analysis was performed on three male knee–ankle–foot-Orthosis users with knee extensor weakness in at least one limb (mean age: 56.3 years (SD 4.0)). Three walking trials were performed with the subjects’ current knee–ankle–foot-Orthosis and then the new stance-control knee–ankle–foot Orthosis (non-randomized before-after trial). Subjects completed a questionnaire about the new stance-control knee–ankle–foot Orthosis and current knee–ankle–foot-Orthosis. Findings A mean increase in knee flexion of 21.1° (SD 8.2) during swing and a greater total knee range of motion was found when walking with the new stance-control knee–ankle–foot Orthosis. Two knee–ankle–foot-Orthosis users experienced a reduction in pelvic obliquity and hip abduction angle abnormalities when walking with the stance-control knee–ankle–foot Orthosis. Two out of three subjects preferred walking with the new stance-control knee–ankle–foot Orthosis over their prescribed knee–ankle–foot-Orthosis. Interpretation The new stance-control knee–ankle–foot Orthosis permitted improved gait kinematics for knee–ankle–foot-Orthosis users while providing knee support in stance and free knee motion in swing at appropriate instants in the gait cycle. Overall, the new stance-control knee–ankle–foot Orthosis provided more natural gait kinematics for Orthosis users compared to conventional knee–ankle–foot-orthoses.
Edward D. Lemaire - One of the best experts on this subject based on the ideXlab platform.
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preliminary kinematic evaluation of a new stance control knee ankle foot Orthosis
Clinical Biomechanics, 2006Co-Authors: Terris Yakimovich, Jonathan Kofman, Edward D. LemaireAbstract:Abstract Background Stance-control knee–ankle–foot orthoses permit free knee motion in swing while providing knee flexion resistance in stance for individuals with quadriceps muscle weakness. However, some stance-control knee–ankle–foot orthoses require full knee extension to engage the knee-joint lock, thereby not providing knee support when climbing stairs or stepping over curbs. Stance-control knee–ankle–foot orthoses that do support a flexed knee are either heavy, bulky, expensive, offer a limited number of locking positions, or cause noise. This paper presents a preliminary kinematic evaluation of a new stance-control knee–ankle–foot Orthosis that was designed to address these limitations. Methods Kinematic gait analysis was performed on three male knee–ankle–foot-Orthosis users with knee extensor weakness in at least one limb (mean age: 56.3 years (SD 4.0)). Three walking trials were performed with the subjects’ current knee–ankle–foot-Orthosis and then the new stance-control knee–ankle–foot Orthosis (non-randomized before-after trial). Subjects completed a questionnaire about the new stance-control knee–ankle–foot Orthosis and current knee–ankle–foot-Orthosis. Findings A mean increase in knee flexion of 21.1° (SD 8.2) during swing and a greater total knee range of motion was found when walking with the new stance-control knee–ankle–foot Orthosis. Two knee–ankle–foot-Orthosis users experienced a reduction in pelvic obliquity and hip abduction angle abnormalities when walking with the stance-control knee–ankle–foot Orthosis. Two out of three subjects preferred walking with the new stance-control knee–ankle–foot Orthosis over their prescribed knee–ankle–foot-Orthosis. Interpretation The new stance-control knee–ankle–foot Orthosis permitted improved gait kinematics for knee–ankle–foot-Orthosis users while providing knee support in stance and free knee motion in swing at appropriate instants in the gait cycle. Overall, the new stance-control knee–ankle–foot Orthosis provided more natural gait kinematics for Orthosis users compared to conventional knee–ankle–foot-orthoses.
Stephen W Hutchins - One of the best experts on this subject based on the ideXlab platform.
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The influence of a powered knee-ankle-foot Orthosis on walking in poliomyelitis subjects: A pilot study
Prosthetics and Orthotics International, 2015Co-Authors: Mokhtar Arazpour, Mohammad Samadian, Mahmoud Joghtaei, Mahmood Bahramizadeh, Alireza Moradi, Monireh Ahmadi Bani, Stephen W Hutchins, Mohammad Ali MardaniAbstract:Background: Traditionally, the anatomical knee joint is locked in extension when walking with a conventional knee-ankle-foot Orthosis. A powered knee-ankle-foot Orthosis was developed to provide restriction of knee flexion during stance phase and active flexion and extension of the knee during swing phase of gait. Objective: The purpose of this study was to determine differences of the powered knee-ankle-foot Orthosis compared to a locked knee-ankle-foot Orthosis in kinematic data and temporospatial parameters during ambulation. Study design: Quasi-experimental design. Methods: Subjects with poliomyelitis (n = 7) volunteered for this study and undertook gait analysis with both the powered and the conventional knee-ankle-foot orthoses. Three trials per Orthosis were collected while each subject walked along a 6-m walkway using a calibrated six-camera three-dimensional video-based motion analysis system. Results: Walking with the powered knee-ankle-foot Orthosis resulted in a significant reduction in both walking speed and step length (both 18%), but a significant increase in stance phase percentage compared to walking with the conventional knee-ankle-foot Orthosis. Cadence was not significantly different between the two test conditions (p = 0.751). There was significantly higher knee flexion during swing phase and increased hip hiking when using the powered Orthosis. Conclusion: The new powered Orthosis permitted improved knee joint kinematic for knee-ankle-foot Orthosis users while providing knee support in stance and active knee motion in swing in the gait cycle. Therefore, the new powered Orthosis provided more natural knee flexion during swing for Orthosis users compared to the locked knee-ankle-foot Orthosis.
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gait evaluation of the advanced reciprocating gait Orthosis with solid versus dorsi flexion assist ankle foot orthoses in paraplegic patients
Prosthetics and Orthotics International, 2013Co-Authors: Monireh Ahmadi Bani, Mohammad Ebrahim Mousavi, Farhad Tabatabai Ghomshe, Mokhtar Arazpour, Stephen W HutchinsAbstract:Background: Mechanical orthoses are used for standing and walking after neurological injury. Most orthoses such as the advanced reciprocating gait Orthosis typically use solid ankle-foot orthoses. Objectives: The goal of this study was to test the effects of ankle dorsiflexion assistance in patients with spinal cord injury when ambulating with an advanced reciprocating gait Orthosis compared to walking with fixed ankles. Study Design: Quasi-experimental. Methods: Four patients with spinal cord injury were fitted with an advanced reciprocating gait Orthosis equipped with solid and dorsiflexion assist-type ankle-foot orthoses and walked at their self-selected speed. Joint angles and spatial- temporal parameters were measured and analyzed. Results: The mean walking speed and stride length were both significantly increased along with cadence by the volunteer subjects when ambulating using the advanced reciprocating gait Orthosis fitted with dorsiflexion assist ankle-foot ortho- ses compared to the advanced reciprocating gait Orthosis with solid ankle-foot orthoses. The mean ankle joint ranges of motion were significantly increased when walking with the advanced reciprocating gait Orthosis with dorsiflexion assist ankle-foot orthoses compared to when using the advanced reciprocating gait Orthosis with the solid ankle-foot orthoses. Knee joint ranges of motion were reduced, and hip joint ranges of motion were increased but not significantly. Conclusion: The advanced reciprocating gait Orthosis fitted with the dorsiflexion assist ankle-foot orthoses had the effect of improving gait parameters when compared to the advanced reciprocating gait Orthosis with solid ankle-foot orthoses. Clinical relevance The advanced reciprocating gait Orthosis with dorsiflexion assist ankle-foot orthoses has the potential to improve hip and ankle joint kinematics and the temporal-spatial parameters of gait in spinal cord injury patients' walking.
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the effect of a knee ankle foot Orthosis incorporating an active knee mechanism on gait of a person with poliomyelitis
Prosthetics and Orthotics International, 2013Co-Authors: Mokhtar Arazpour, Gholamreza Rouhi, Ahmad Chitsazan, Monireh Ahmadi Bani, Farhad Tabatabai Ghomshe, Stephen W HutchinsAbstract:BACKGROUND: The aim of this case study was to identify the effect of a powered stance control knee ankle foot Orthosis on the kinematics and temporospatial parameters of walking by a person with poliomyelitis when compared to a knee ankle foot Orthosis. CASE DESCRIPTION AND METHODS: A knee ankle foot Orthosis was initially manufactured by incorporating drop lock knee joints and custom molded ankle foot orthoses and fitted to a person with poliomyelitis. The Orthosis was then adapted by adding electrically activated powered knee joints to provide knee extension torque during stance and also flexion torque in swing phase. Lower limb kinematic and kinetic data plus data for temporospatial parameters were acquired from three test walks using each Orthosis. FINDINGS AND OUTCOMES: Walking speed, step length, and vertical and horizontal displacement of the pelvis decreased when walking with the powered stance control knee ankle foot Orthosis compared to the knee ankle foot Orthosis. When using the powered stance control knee ankle foot Orthosis, the knee flexion achieved during swing and also the overall pattern of walking more closely matched that of normal human walking. The reduced walking speed may have caused the smaller compensatory motions detected when the powered stance control knee ankle foot Orthosis was used. CONCLUSION: The new powered SCKAFO facilitated controlled knee flexion and extension during ambulation for a volunteer poliomyelitis person.
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evaluation of a novel powered gait Orthosis for walking by a spinal cord injury patient
Prosthetics and Orthotics International, 2012Co-Authors: Mokhtar Arazpour, Ahmad Chitsazan, Mohammad Ebrahim Mousavi, Esmaeil Ebrahimi Takamjani, Mehdi Rahgozar, Gholamreza Aminian, Stephen W Hutchins, Farhad Tabatabai Ghomshe, Monireh Ahmadi BaniAbstract:Background: The aim of this case study was to analyze the effect on gait parameters of a new design of powered gait Orthosis which applied synchronized motions to both the hip and knee joints when utilized for walking by a spinal cord injury (SCI) patient.Case Description and Methods: Two orthoses were evaluated while worn by an incomplete SCI subject. Gait evaluation was performed when walking with an isocentric reciprocating gait Orthosis (IRGO) and compared to that demonstrated by a newly developed powered version. This new Orthosis was based on the IRGO superstructure but incorporated powered hip and knee joints using electrically motorized actuators.Findings and Outcomes: These gait parameters were improved when compared to standard IRGO and initial testing with the Orthosis with only the hip or the knee joints activated in isolation. Maximum hip flexion and extension angles, as well as the maximum knee flexion and extension angles all increased when walking with the powered RGO compared to the IRGO....
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evaluation of a novel powered hip Orthosis for walking by a spinal cord injury patient a single case study
Prosthetics and Orthotics International, 2012Co-Authors: Mokhtar Arazpour, Ahmad Chitsazan, Mohammad Ebrahim Mousavi, Esmaeil Ebrahimi Takamjani, Mehdi Rahgozar, Gholamreza Aminian, Stephen W Hutchins, Farhad Tabatabai Ghomshe, Monireh Ahmadi BaniAbstract:BACKGROUND: The aim of this case study was to identify the effect of a powered hip Orthosis on the kinematics and temporal-spatial parameters of walking by a patient with spinal cord injury (SCI). CASE DESCRIPTION AND METHODS: Two orthoses were evaluated while worn by an incomplete SCI subject with a T-8level of injury. Gait evaluation was performed when walking with an Isocentric Reciprocating Gait Orthosis (IRGO) and compared to that demonstrated by a newly powered version of the Orthosis; based on the IRGO superstructure but incorporating powered hip joints using an electrically motorized actuator that produced active hip joint extension and flexion. FINDINGS AND OUTCOMES: The powered hip Orthosis, when compared to the IRGO, increased the speed of walking, the step length and also the cadence demonstrated by this subject. Vertical and horizontal compensatory motions with new Orthosis decreased. Hip angles when walking with this Orthosis were comparative to those demonstrated by normal walking patterns. CONCLUSIONS: The hip actuator produced positive effects on the kinematics and temporal-spatial parameters of gait during level-ground walking trials, resulting in an alternative approach to walking by SCI patients.
Terris Yakimovich - One of the best experts on this subject based on the ideXlab platform.
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preliminary kinematic evaluation of a new stance control knee ankle foot Orthosis
Clinical Biomechanics, 2006Co-Authors: Terris Yakimovich, Jonathan Kofman, Edward D. LemaireAbstract:Abstract Background Stance-control knee–ankle–foot orthoses permit free knee motion in swing while providing knee flexion resistance in stance for individuals with quadriceps muscle weakness. However, some stance-control knee–ankle–foot orthoses require full knee extension to engage the knee-joint lock, thereby not providing knee support when climbing stairs or stepping over curbs. Stance-control knee–ankle–foot orthoses that do support a flexed knee are either heavy, bulky, expensive, offer a limited number of locking positions, or cause noise. This paper presents a preliminary kinematic evaluation of a new stance-control knee–ankle–foot Orthosis that was designed to address these limitations. Methods Kinematic gait analysis was performed on three male knee–ankle–foot-Orthosis users with knee extensor weakness in at least one limb (mean age: 56.3 years (SD 4.0)). Three walking trials were performed with the subjects’ current knee–ankle–foot-Orthosis and then the new stance-control knee–ankle–foot Orthosis (non-randomized before-after trial). Subjects completed a questionnaire about the new stance-control knee–ankle–foot Orthosis and current knee–ankle–foot-Orthosis. Findings A mean increase in knee flexion of 21.1° (SD 8.2) during swing and a greater total knee range of motion was found when walking with the new stance-control knee–ankle–foot Orthosis. Two knee–ankle–foot-Orthosis users experienced a reduction in pelvic obliquity and hip abduction angle abnormalities when walking with the stance-control knee–ankle–foot Orthosis. Two out of three subjects preferred walking with the new stance-control knee–ankle–foot Orthosis over their prescribed knee–ankle–foot-Orthosis. Interpretation The new stance-control knee–ankle–foot Orthosis permitted improved gait kinematics for knee–ankle–foot-Orthosis users while providing knee support in stance and free knee motion in swing at appropriate instants in the gait cycle. Overall, the new stance-control knee–ankle–foot Orthosis provided more natural gait kinematics for Orthosis users compared to conventional knee–ankle–foot-orthoses.
J P Paul - One of the best experts on this subject based on the ideXlab platform.
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biomechanics of longitudinal arch support mechanisms in foot orthoses and their effect on plantar aponeurosis strain
Clinical Biomechanics, 1996Co-Authors: Geza F Kogler, S E Solomonidis, J P PaulAbstract:Objective. The purpose of this investigation was to quantify the longitudinal arch support properties of several types of foot Orthosis. Design. An in vitro method that simulated ‘static stance” was used to determine arch support capabilities, with plantar aponeurosis strain implemented as the performance measure. Background. A longitudinal arch support mechanism of an Orthosis resists depression of the foot's arches by transferring a portion of the load to the medial structures of the foot. Since the plantar aponeurosis is in tension when the foot is loaded, a quantifiable decrease in strain should occur with an adequate orthotic arch control mechanism. Methods. A differential variable reluctance transducer was surgically implanted in the plantar aponeurosis of cadaveric donor limb feet (n= 7). Each specimen was mounted in an electromechanical test machine which applied a load of up to 900 N axially to the tibia. The test schedule was divided into seven test conditions: specimen barefoot; specimen with shoe and specimen with shoe and five different orthoses. Results. The University of California Biomechanics Laboratory Shoe Insert and two other foot orthoses significantly decreased the strain in the plantar aponeurosis compared to the barefoot control and were considered effective arch supports (P <0.05). The functional foot Orthosis, stock Orthosis, and test shoe did not effectively reduce plantar aponeurosis strain. Significant variations of time required to achieve the specified load levels were recorded among the test conditions, indicating the relative cushioning properties of the shoe/ Orthosis systems. Conclusions. The patterns of plantar aponeurosis strain observed in cadaveric tests suggest that certain types of orthoses are more effective than others in the support of the foot's longitudinal arches. It is suggested that to support the longitudinal arches of the foot effectively the medial surface contours of the Orthosis must stabilize the apical bony structure of the foot's arch.
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biomechanics of longitudinal arch support mechanisms in foot orthoses and their effect on plantar aponeurosis strain
Clinical Biomechanics, 1996Co-Authors: Geza F Kogler, S E Solomonidis, J P PaulAbstract:OBJECTIVE: The purpose of this investigation was to quantify the longitudinal arch support properties of several types of foot Orthosis. DESIGN: An in vitro method that simulated 'static stance' was used to determine arch support capabilities, with plantar aponeurosis strain implemented as the performance measure. BACKGROUND: A longitudinal arch support mechanism of an Orthosis resists depression of the foot's arches by transferring a portion of the load to the medial structures of the foot. Since the plantar aponeurosis is in tension when the foot is loaded, a quantifiable decrease in strain should occur with an adequate orthotic arch control mechanism. METHODS: A differential variable reluctance transducer was surgically implanted in the plantar aponeurosis of cadaveric donor limb feet (n = 7). Each specimen was mounted in an electromechanical test machine which applied a load of up to 900 N axially to the tibia. The test schedule was divided into seven test conditions: specimen barefoot; specimen with shoe and specimen with shoe and five different orthoses. RESULTS: The University of California Biomechanics Laboratory Shoe Insert and two other foot orthoses significantly decreased the strain in the plantar aponeurosis compared to the barefoot control and were considered effective arch supports (P < 0.05). The functional foot Orthosis, stock Orthosis, and test shoe did not effectively reduce plantar aponeurosis strain. Significant variations of time required to achieve the specified load levels were recorded among the test conditions, indicating the relative cushioning properties of the shoe/Orthosis systems. CONCLUSIONS: The patterns of plantar aponeurosis strain observed in cadaveric tests suggest that certain types of orthoses are more effective than others in the support of the foot's longitudinal arches. It is suggested that to support the longitudinal arches of the foot effectively the medial surface contours of the Orthosis must stabilize the apical bony structure of the foot's arch. RELEVANCE: Reducing tension in the plantar aponeurosis is an important treatment objective for orthotic management of plantar fasciitis. Therefore it is of great clinical interest to know whether the longitudinal arch support mechanism of specific foot orthoses have benefits with respect to the loading of the plantar aponeurosis.
