Mechanical problem in 3D printed ankle-foot orthoses with function of energy storage

2018 ◽  
Author(s):  
Chien-Hsien Yeh ◽  
Yi-Chun Tsai ◽  
Fong-Chin Su ◽  
Li-Chieh Kuo ◽  
Kai Chang ◽  
...  
Keyword(s):  
Energy Storage ◽  
Foot Orthoses ◽  
Mechanical Problem ◽  
Ankle Foot Orthoses ◽  
3D Printed

scholarly journals A validated computational framework to evaluate the stiffness of 3D printed ankle foot orthoses

2019 ◽  
Vol 22 (8) ◽  
pp. 880-887 ◽  
Author(s):  
Alessio Ielapi ◽  
Nicolas Lammens ◽  
Wim Van Paepegem ◽  
Malcolm Forward ◽  
Jan Patrick Deckers ◽  
...  
Keyword(s):  
Foot Orthoses ◽  
Computational Framework ◽  
Ankle Foot Orthoses ◽  
3D Printed

Assessment of Mechanical Characteristics of Ankle-Foot Orthoses

2018 ◽  
Vol 140 (7) ◽  
Author(s):  
Amanda Wach ◽  
Linda McGrady ◽  
Mei Wang ◽  
Barbara Silver-Thorn
Keyword(s):  
Energy Storage ◽  
Functional Outcomes ◽  
Mechanical Characteristics ◽  
Leaf Spring ◽  
Clinical Test ◽  
Foot Orthoses ◽  
Ankle Motion ◽  
Compressive Stiffness ◽  
Ankle Foot Orthoses ◽  
Insight Into

Recent designs of ankle-foot orthoses (AFOs) have been influenced by the increasing demand for higher function from active individuals. The biomechanical function of the individual and device is dependent upon the underlying mechanical characteristics of the AFO. Prior mechanical testing of AFOs has primarily focused on rotational stiffness to provide insight into expected functional outcomes; mechanical characteristics pertaining to energy storage and release have not yet been investigated. A pseudostatic bench testing method is introduced to characterize compressive stiffness, device deflection, and motion of solid-ankle, anterior floor reaction, posterior leaf spring, and the intrepid dynamic exoskeletal orthosis (IDEO) AFOs. Each of these four AFOs, donned over a surrogate limb, were compressively loaded at different joint angles to simulate the foot-shank orientation during various subphases of stance. In addition to force–displacement measurements, deflection of each AFO strut and rotation of proximal and supramalleolar segments were analyzed. Although similar compressive stiffness values were observed for AFOs designed to reduce ankle motion, the corresponding strut deflection profile differed based on the respective fabrication material. For example, strut deflection of carbon-fiber AFOs resembled column buckling. Expanded clinical test protocols to include quantification of AFO deflection and rotation during subject use may provide additional insight into design and material effects on performance and functional outcomes, such as energy storage and release.

scholarly journals Feasibility of designing, manufacturing and delivering 3D printed ankle-foot orthoses: a systematic review

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Elizabeth Wojciechowski ◽  
Angela Y. Chang ◽  
Daniel Balassone ◽  
Jacqueline Ford ◽  
Tegan L. Cheng ◽  
...  
Keyword(s):  
Systematic Review ◽  
Foot Orthoses ◽  
Ankle Foot Orthoses ◽  
3D Printed

scholarly journals Individual stiffness optimization of dorsal leaf spring ankle–foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Niels F. J. Waterval ◽  
Merel-Anne Brehm ◽  
Jaap Harlaar ◽  
Frans Nollet
Keyword(s):  
Muscle Weakness ◽  
Energy Cost ◽  
Activity Level ◽  
Calf Muscle ◽  
Leaf Spring ◽  
Foot Orthoses ◽  
Ankle Foot Orthoses ◽  
The Individual ◽  
Optimal Stiffness ◽  
Walking Energy Cost

Abstract Background In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle–foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness. Methods Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected. Results In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s, p = 0.003). Additionally, a larger ankle range of motion (+ 1.3 ± 0.3 degrees, p < 0.001) and higher ankle power (+ 0.16 ± 0.04 W/kg, p < 0.001) were found with the experimentally optimized stiffness compared to the supplier recommended stiffness. Conclusions In people with calf muscle weakness, current supplier’s recommendations for the CA7 stiffness level result in the provision of DLS-AFOs that are too stiff and only achieve 80% of the reduction in energy cost achieved with an individual optimized stiffness. It is recommended to experimentally optimize the CA7 stiffness in people with calf muscle weakness in order to maximize treatment outcomes. Trial registration Nederlands Trial Register 5170. Registration date: May 7th 2015. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5170.

State of the Art Review of Knee–Ankle–Foot Orthoses

2015 ◽  
Vol 43 (2) ◽  
pp. 427-441 ◽  
Author(s):  
Feng Tian ◽  
Mohamed Samir Hefzy ◽  
Mohammad Elahinia
Keyword(s):  
State Of The Art ◽  
Foot Orthoses ◽  
Ankle Foot Orthoses

Quantification of gait asymmetry in patients with ankle foot orthoses based on hip–hip cyclograms

2014 ◽  
Vol 34 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Patrik Kutilek ◽  
Vladimir Socha ◽  
Slavka Viteckova ◽  
Zdenek Svoboda
Keyword(s):  
Foot Orthoses ◽  
Ankle Foot Orthoses ◽  
Gait Asymmetry

scholarly journals The Importance of Being Earnest about Shank and Thigh Kinematics Especially When Using Ankle-Foot Orthoses

2010 ◽  
Vol 34 (3) ◽  
pp. 254-269 ◽  
Author(s):  
Elaine Owen
Keyword(s):  
Joint Kinematics ◽  
Foot Orthoses ◽  
Traditional Beliefs ◽  
Vertical Angle ◽  
Gait Biomechanics ◽  
Normal Gait ◽  
Ankle Foot Orthoses ◽  
Pathological Gait ◽  
Kinematics And Kinetics

This paper reviews and summarizes the evidence for important observations of normal and pathological gait and presents an approach to rehabilitation and orthotic management, which is based on the significance of shank and thigh kinematics for standing and gait. It discusses normal gait biomechanics, challenging some traditional beliefs, the interrelationship between segment kinematics, joint kinematics and kinetics and their relationship to orthotic design, alignment and tuning. It proposes a description of four rather than three rockers in gait; a simple categorization of pathological gait based on shank kinematics abnormality; an algorithm for the designing, aligning and tuning of AFO-Footwear Combinations; and an algorithm for determining the sagittal angle of the ankle in an AFO. It reports the results of research on Shank to Vertical Angle alignment of tuned AFO-Footwear Combinations and on the use of ‘point loading’ rocker soles.

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