Biomechanical Model Representing Energy Storing Prosthetic Feet

2010 ◽  
Author(s):  
Francy L. Sinatra ◽  
Stephanie L. Carey ◽  
Rajiv Dubey
Keyword(s):  
Motion Analysis ◽  
Lower Limb ◽  
Biomechanical Model ◽  
Body Segment ◽  
Prosthetic Foot ◽  
Biomechanical Models ◽  
Prosthetic Feet ◽  
Analysis System ◽  
Lower Limb Amputees ◽  
Metabolic Information

Previous studies have been conducted to develop a biomechanical model for a human’s lower limb. Amongst them, there have been several studies trying to quantify the kinetics and kinematics of lower-limb amputees through motion analysis [5, 10, 11]. Currently, there are various designs for lower-limb prosthetic feet such as the Solid Ankle Cushion Heel (SACH) from Otto Bock (Minneapolis) or the Flex Foot from Ossur (California). The latter is a prosthetic foot that allows for flexibility while walking and running. Special interest has been placed in recording the capabilities of these energy-storing prosthetic feet. This has been done through the creation of biomechanical models with motion analysis. In these previous studies the foot has been modeled as a single rigid-body segment, creating difficulties when trying to calculate the power dissipated by the foot [5, 20, 21]. This project studies prosthetic feet with energy-storing capabilities. The purpose is to develop an effective way of calculating power by using a biomechanical model. This was accomplished by collecting biomechanical data using an eight camera VICON (Colorado) motion analysis system including two AMTI (BP-400600, Massachusetts) force plates. The marker set that was used, models the foot using several segments, hence mimicking the motion the foot undergoes and potentially leading to greater accuracy. By developing this new marker set, it will be possible to combine the kinematic and kinetic profile gathered from it with previous studies that determined metabolic information. This information will allow for the better quantification and comparison of the energy storage and return (ES AR) feet and perhaps the development of new designs.

The Evaluation of Foot Rockers on the Kinematic Parameters of Individuals With Diabetes

2017 ◽  
Vol 11 (4) ◽  
pp. 322-329 ◽  
Author(s):  
Mohammad Taghi Karimi
Keyword(s):  
Range Of Motion ◽  
Motion Analysis ◽  
Lower Limb ◽  
P Value ◽  
Motion Analysis System ◽  
Kinematic Parameters ◽  
Hip Joints ◽  
Plantar Surface ◽  
Analysis System ◽  
Discernible Difference

Background: A variety of shoe modifications have been used to reduce the forces applied on the plantar surface of the foot in those with diabetes. Toe and heel rockers are 2 of the most common types used. The aim of this study is to evaluate the effect of these shoe modifications on the kinematics of both normal and diabetic individuals. Method: Two groups of healthy and diabetic individuals were recruited for this study. The Qualysis motion analysis system was used to record the motions of participants while walking with shoes with toe and a combination of toe and heel rockers (combined). The effects of the type of rockers used and the effect of groups were determined using MANOVA. Results: Results of the study demonstrated no discernible difference between the spatiotemporal and range of motion of the ankle, knee, and hip joints while walking with a toe and combined rockers. There was also no difference between healthy and diabetic individuals in relation to these parameters (P value >.05). Conclusion: Results of this study demonstrated no difference between the spatiotemporal and range of motion of lower-limb joints in healthy and diabetic individuals when walking with toe and combined rockers. Because the use of these rockers did not influence the kinematics of the joints while walking, it is recommended that they be used for this group of individuals if they influence the forces applied on the foot. Levels of Evidence: Level IV

Effect of Walking Speed on Angular Stiffness and Roll-Over Shape of the Intact and Prosthetic Feet of Transtibial Amputees

2013 ◽  
Author(s):  
Michelle Roland ◽  
Peter G. Adamczyk ◽  
Michael E. Hahn
Keyword(s):  
Lower Limb ◽  
Stance Phase ◽  
Walking Speed ◽  
Plantar Flexor ◽  
Limb Function ◽  
Prosthetic Foot ◽  
Material Stiffness ◽  
Prosthetic Feet ◽  
Transtibial Amputees ◽  
Lower Limb Function

The calculated roll-over shape and respective radius of intact and prosthetic feet has been shown to be a useful measure of lower limb function during walking [1–2]. Hansen et al [3] reported that the roll-over radius, R, is constant over a range of speeds for the intact foot-ankle system. It may be assumed that the prosthetic foot R would also be constant with increased walking speed. Similarly, the angular stiffness of prosthetic feet is not likely to change with walking speed, as the material stiffness remains unchanged. However, the effective angular stiffness of the intact ankle may increase with the plantar flexor moment during the stance phase of gait, which typically increases in magnitude with walking speed.

The Effect of Prosthetic Foot Component Stiffness on Gait Initiation and Termination of Transtibial Amputees

2012 ◽  
Author(s):  
Travis J. Peterson ◽  
Michelle Roland ◽  
Peter Adamczyk ◽  
Michael E. Hahn
Keyword(s):  
Lower Limb ◽  
Gait Initiation ◽  
Gait Stability ◽  
Functional Activities ◽  
Prosthetic Foot ◽  
Limb Stiffness ◽  
Stiffness Characteristics ◽  
And Performance ◽  
Transtibial Amputees ◽  
Lower Limb Amputees

Matching a prosthetic foot to meet the activity requirements of the user can be a difficult process. The ideal stiffness characteristics of different functional activities may vary. This variation dictates that the prescribed foot must be a compromise of multiple ideals due to functional necessity. The effects of lower limb stiffness have been studied in regards to their ability to reproduce “normal” lower limb mechanics [1,2]. Other studies have tracked gait stability and performance measures for lower limb amputees during gait initiation and termination [3–5]. However, it remains unknown what effects prosthetic stiffness may have on amputee function during gait initiation and termination. The objective of this study was to compare the effects of different component stiffness ranges on locomotion and stability measures during gait initiation and termination

Development of a Bimodal Ankle-Foot Prosthesis for Walking and Standing/Swaying

2013 ◽  
Vol 7 (3) ◽  
Author(s):  
Andrew H. Hansen ◽  
Eric A. Nickel
Keyword(s):  
Mechanical Properties ◽  
Lower Limb ◽  
Mechanical Stability ◽  
Balance Confidence ◽  
Prosthetic Foot ◽  
Human Ankle ◽  
Body Center ◽  
Impaired Balance ◽  
Prosthetic Feet ◽  
Lower Height

The human ankle-foot system conforms to a circular effective rocker shape for walking, but to a much flatter effective shape for standing and swaying. Many persons with lower limb amputations have impaired balance and reduced balance confidence, and may benefit from prostheses designed to provide flatter effective rocker shapes during standing and swaying tasks. This paper describes the development and testing of an ankle-foot prosthesis prototype that provides distinctly different mechanical properties for walking and standing/swaying. The prototype developed was a single-axis prosthetic foot with a lockable ankle for added stability during standing and swaying. The bimodal ankle-foot prosthesis prototype was tested on pseudoprostheses (walking boots with prosthetic feet beneath) for walking and standing/swaying loads, and was compared to an Otto Bock single-axis prosthetic foot and to able-bodied data collected in a previous study. The height-normalized radius of the effective rocker shape for walking with the bimodal ankle-foot prototype was equal to that found earlier for able-bodied persons (0.17); the standing and swaying effective shape had a lower height-normalized radius (0.70) compared with that previously found for able-bodied persons (1.11). The bimodal ankle-foot prosthesis prototype had a similar radius as the Otto Bock single-axis prosthetic foot for the effective rocker shape for walking (0.17 for both), but had a much larger radius for standing and swaying (0.70 for bimodal, 0.34 for single-axis). The results suggest that the bimodal ankle-foot prosthesis prototype provides two distinct modes, including a biomimetic effective rocker shape for walking and an inherently stable base for standing and swaying. The radius of the prototype's effective rocker shape for standing/swaying suggests that it may provide inherent mechanical stability to a prosthesis user, since the radius is larger than the typical body center of mass’s distance from the floor (between 50–60% of height). Future testing is warranted to determine if the bimodal ankle-foot prosthesis will increase balance and balance confidence in prosthesis users.

KINEMATICS PROPERTIES AND ENERGY COST OF BELOW-KNEE AMPUTEES

2001 ◽  
Vol 13 (02) ◽  
pp. 99-107 ◽  
Author(s):  
KUO-FENG HUANG ◽  
YOU-LI CHOU ◽  
FONG-CHIN SU ◽  
PEI-HIS CHOU
Keyword(s):  
Motion Analysis ◽  
Energy Cost ◽  
Dynamic Performance ◽  
Camera Motion ◽  
Prosthetic Foot ◽  
Gait Characteristics ◽  
Metabolic Measurement ◽  
Prosthetic Feet ◽  
Camera Motion Analysis ◽  
Dynamic Gait

This study scientifically measures the dynamic gait characteristics and energy cost of six male below-knee amputees, three vascular and three traumatic, while wearing SACH, single axis and multiple axis prosthetic feet via six-camera motion analysis, metabolic measurement cart and heavy-duty treadmill. Subjective results are additionally determined via questionnaire after testing. Motion analysis showed statistically significant differences at p < 0.05 between the solid ankle cushion heel (SACH), single axis and multiple axis foot in the velocity, cadence, stride length end gait cycle. Significant differences were found in energy cost among the prosthetic feet tested, and significant changes in walking under different speeds and different inclines. Results provide quantitative and qualitative information about the dynamic performance of the various feet which can be helpful in prescribing the optimal prosthetic foot for individual amputees.

COMPARISON OF LOWER-LIMB AMPUTEES' GAIT ON SLOPED SURFACES WITH DIFFERENT PROSTHETIC FEET

2012 ◽  
Vol 45 ◽  
pp. S243
Author(s):  
Mohammad Hossein Mohammadniay Gharaei ◽  
Maede Alavikia ◽  
Ali Matinmanesh
Keyword(s):  
Lower Limb ◽  
Prosthetic Feet ◽  
Lower Limb Amputees

scholarly journals THE INFLUENCE OF HYDRAULIC ANKLES AND MICROPROCESSOR-CONTROL ON THE BIOMECHANICS OF TRANS-TIBIAL AMPUTEES DURING QUIET STANDING ON A 5° SLOPE

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Michael McGrath ◽  
Katherine C. Davies ◽  
Piotr Laszczak ◽  
Beata Rek ◽  
Joe McCarthy ◽  
...  
Keyword(s):  
Lower Limb ◽  
Reaction Force ◽  
Quiet Standing ◽  
Microprocessor Control ◽  
Prosthetic Foot ◽  
Prosthetic Limbs ◽  
Ankle Joints ◽  
Sound Side ◽  
Computer Controlled ◽  
Prosthetic Feet

BACKGROUND: Lower limb amputees have a high incidence of comorbidities, such as osteoarthritis, which are believed to be caused by kinetic asymmetries. A lack of prosthetic adaptation to different terrains requires kinematic compensations, which may influence these asymmetries. METHOD: Six SIGAM grade E-F trans-tibial amputees (one bilateral) wore motion capture markers while standing on force plates, facing down a 5° slope. The participants were tested under three prosthetic conditions; a fixed attachment foot (FIX), a hydraulic ankle (HYD) and a microprocessor foot with a ‘standing support’ mode (MPF). The resultant ground reaction force (GRF) and support moment for prosthetic and sound limbs were chosen as outcome measures. These were compared between prosthetic conditions and to previously captured able-bodied control data. RESULTS: The distribution of GRF between sound and prosthetic limbs was not significantly affected by foot type. However, the MPF condition required fewer kinematic compensations, leading to a reduction in sound side support moment of 59% (p=0.001) and prosthetic side support moment of 43% (p=0.02) compared to FIX. For the bilateral participant, only the MPF positioned the GRF vector anterior to the knees, reducing the demand on the residual joints to maintain posture. CONCLUSION: For trans-tibial amputees, loading on lower limb joints is affected by prosthetic foot technology, due to the kinematic compensations required for slope adaptation. MPFs with ‘standing support’ might be considered reasonable and necessary for bilateral amputees, or amputees with stability problems due to the reduced biomechanical compensations evident. LAYMAN’S ABSTRACT: Lower limb prostheses work well on flat ground but often don’t adapt well to uneven ground or slopes. As a result, amputees tend to put more of their weight through their healthy leg. This can lead to problems like back pain and arthritis. In this study, the posture and weight distribution of below knee amputees were analysed while they stood facing down a slope. They did this with three different prosthetic feet; one with no ‘ankle’ joint, one with an ‘ankle’ (which could always move) and one with a computer-controlled ‘ankle’ (which could adapt to the slope but then resist movement when the wearer was stood still). Changing the prosthetic feet did not affect the amount of weight put through each limb, but when they had ‘ankle’ joints, the amputees were able to stand up straight, with a better posture. This meant that the demand on their joints was reduced, particularly on the healthy limb. One participant had below knee amputations on both legs. For this participant, only the computer-controlled device allowed her to stand up straight and well balanced. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/33517/25933 How to Cite: McGrath M, Davies KC, Laszczak P, Rek B, McCarthy J, Zahedi S, Moser D. The influence of hydraulic ankles and microprocessor-control on the biomechanics of trans-tibial amputees during quiet standing on a 5° slope. Canadian Prosthetics & Orthotics Journal. 2019;Volume2, Issue2, No.2. https://doi.org/10.33137/cpoj.v2i2.33517 CORRESPONDING AUTHOR Dr. Michael McGrath,Research Scientist–Clinical EvidenceBlatchford Group, Unit D Antura, Bond Close, Basingstoke, RG24 8PZ, United KingdomEmail: [email protected]: https://orcid.org/0000-0003-0195-970X  

scholarly journals Experimental characterization of the moment-angle curve during level and slope locomotion of transtibial amputee: Which parameters can be extracted to quantify the adaptations of microprocessor prosthetic ankle?

2021 ◽  
pp. 095441192110065
Author(s):  
Julie Davot ◽  
Marie Thomas-Pohl ◽  
Coralie Villa ◽  
Xavier Bonnet ◽  
Eric Lapeyre ◽  
...  
Keyword(s):  
Range Of Motion ◽  
Lower Limb ◽  
Hydraulic Actuator ◽  
Period Range ◽  
Transtibial Amputation ◽  
Prosthetic Foot ◽  
Available Energy ◽  
Ankle Kinematics ◽  
Prosthetic Feet ◽  
The Moment

In case of transtibial amputation, the deficit resulting from the loss of the lower limb can be partly compensated with a prosthetic foot and adapted rehabilitation. New prosthetic feet have been developed for transtibial amputees to mimic ankle adaptability to varying terrain. Among them, Microprocessor Prosthetic Ankles (MPA) have a microprocessor to control an electric or a hydraulic actuator to adapt ankle kinematics in stairs and slopes. The objective is to investigate parameters extracted from the moment-angle curve (MAC) and use them to compare 3 MPA during level and slope locomotion against energy storing and return (ESR) foot. Five persons with lower limb transtibial amputation successively fitted with 3 MPA (Propriofoot™, Elan™, Meridium™) compared to their ESR foot. The participants had 2 weeks of adaptation before data acquisition and then a 3 week wash-out period. Range of motion, equilibrium point, hysteresis, late stance energy released, and quasi-stiffness were computed on level ground and 12% slope (upward and downward) thanks to the MAC at the ankle. The study shows the relevance of MAC parameters to evaluate the behavior of MPA. In particular, compared to ESR, all MPA tested in the present study demonstrated a better angle adaptation between walking conditions but a decrease of available energy for the propulsion. Among MPA, main results were: (i) for the Propriofoot™: an adaptation of the ankle angle without modification of the pattern of the MAC (ii) for the Elan™: a limited adaptation of the range of motion but a modification of the energy released (iii) for the Meridium™, the highest adaptation of the range of motion but the lowest available energy of propulsion. One of the main findings of the research is to show and quantify the relationship between range of motion and energy available when using different prosthetic feet in different walking conditions.

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