scholarly journals A Novel Approach For Ankle Foot Orthosis Developed By Three Dimensional Technologies

Author(s):  
R M Belokar ◽  
H K Banga ◽  
R Kumar
2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Chloe L. Chung ◽  
Denis J. DiAngelo ◽  
Douglas W. Powell ◽  
Max R. Paquette

Abstract Patients who sustain irreversible cartilage damage or joint instability from ankle injuries are likely to develop ankle osteoarthritis (OA). A dynamic ankle orthosis (DAO) was recently designed with the intent to offload the foot and ankle using a distractive force, allowing more natural sagittal and frontal plane ankle motion during gait. To evaluate its efficacy, this study compared ankle joint kinematics and plantar pressures among the DAO, standard double upright ankle-foot orthosis (DUAFO), and a nonorthosis control (CON) condition in healthy adults during walking. Ten healthy subjects (26 ± 3.8 yr; 69.6 ± 12.7 kg; and 1.69 ± 0.07 m) walked on a treadmill at 1.4 m/s in three orthosis conditions: CON, DAO, and DUAFO. Ankle kinematics were assessed using a three-dimensional (3D) motion capture system and in-shoe plantar pressures were measured for seven areas of the foot. DAO reduced hallux peak plantar pressures (PPs) compared to CON and DUAFO. PPs under toes 2–5 were smaller in DAO than DUAFO, but greater in DUAFO compared to CON. Early stance peak plantarflexion (PF) angular velocity was smaller in DAO compared to CON and DUAFO. Eversion (EV) ROM was much smaller in DUAFO compared to CON and DAO. Early stance peak eversion angular velocity was smaller in DAO and much smaller in DUAFO compared to CON. This study demonstrates the capacity of the DAO to provide offloading during ambulation without greatly affecting kinematic parameters including frontal plane ankle motion compared to CON. Future work will assess the effectiveness of the DAO in a clinical osteoarthritic population.


2012 ◽  
Vol 37 (3) ◽  
pp. 212-221 ◽  
Author(s):  
Sumiko Yamamoto ◽  
Naoki Tomokiyo ◽  
Tadashi Yasui ◽  
Toshikazu Kawaguchi

Background: An ankle-foot orthosis with an oil damper was previously developed to assist the first rocker function during gait, but the effects of the amount of resistive moment generated on gait have not been clarified. Objectives: To measure the amount of resistive moment generated by the ankle-foot orthosis with an oil damper during gait and determine its effect on the gait of patients with stroke. Study Design: Preliminary cross-sectional study. Methods: The gait of four patients with stroke in the chronic phase was measured in four conditions: without an ankle-foot orthosis and with the ankle-foot orthosis with an oil damper generating three different amounts of resistive moment. Measurements were taken with a three-dimensional motion analysis system and a specially designed device to determine the resistive moment. Results: The resistive moment was observed in the former half in stance of the paretic limb, and its magnitude was less than 10 N m. Some gait parameters related to terminal stance and preswing were affected by the amount of resistive moment. The forward component of floor reaction force and the shank vertical angle showed peak values when the patients reported feeling most comfortable during gait. Conclusion: Although the resistive moment generated by the ankle-foot orthosis with an oil damper was small, it was sufficient to alter gait. Clinical relevance To maximize the effectiveness of ankle-foot orthoses, it is necessary to know the effects of resistive moment on the gait of patients with stroke. The ankle-foot orthosis with an oil damper assists the first rocker function in gait and also affects the gait in a later phase in stance. The peak values of some gait parameters coincided with patients reporting gait to be most comfortable. It is important to know that ankle-foot orthosis with an oil damper assistance in the first rocker alters the weight acceptance on the paretic limb and affects the gait parameters related to propulsion ability in stance.


2019 ◽  
Vol 43 (5) ◽  
pp. 354-361
Author(s):  
Ayham Darwich ◽  
Hasan Nazha ◽  
Aleen Sliman ◽  
William Abbas

This study focuses on the drop foot case related to hyperthyroidism of the ankle joint resulting in the relaxation of the toes during walking. This condition requires treatment using an ankle–foot orthosis. Traditional orthosis techniques lack precision and depend on the skill of the fabricator. This research aims to make a bias in ankle–foot orthosis design and analysis methods, where a complete methodology of numerical design and testing has been proposed using advanced engineering software. A numerical model of the patient’s foot was generated and used to design an ankle–foot orthosis model using SolidWorks. The designed model was mechanically analyzed by the finite element method using ANSYS Workbench 16.1 under different static and dynamic loading conditions. The ankle–foot orthosis model was numerically designed and analyzed before the manufacturing process. This is believed to reduce time and material loss and foster the use of numerical models in biomedical applications. This study suggests focusing on the design and analysis of orthoses according to the patient’s measurements. This is expected to increase the comfort and raise the level of treatment. Numerical design methods also enable precise manufacturing using computerized devices such as three-dimensional printers.


2021 ◽  
Author(s):  
Jimmy Chun-Ming Fu ◽  
Cyuan-Fong Li ◽  
Yu-Hsuan Hsiao ◽  
Feng-Zu Sheen ◽  
Yi-Jen Chen ◽  
...  

Abstract BackgroundThree-dimensional printing (3DP) is a promising technique utilized in orthosis fabrication, including ankle foot orthosis for stroke patients. However, the effects on ankle biomechanics remains unclear. ObjectivesTo compare the plantar pressure distribution and patient’s subjective experience in chronic stroke patients during 3DP hinged ankle foot orthosis (3DP-HAFO) and anterior ankle foot orthosis (A-AFO) walking MethodsTen patients with first-ever unilateral stroke were enrolled in this study. All patients performed 10-meter walk test in 3 different conditions, including 3DP-HAFO walking, A-AFO walking, and bare foot walking. The plantar pressure parameters including contact area, maximum force, and peak pressure were collected using Pedar X insole system. Gait asymmetry analysis of the plantar pressure parameters was conducted. Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST) was used for patient’s satisfaction.Results3DP-HAFO walking revealed significant increase in medial midfoot peak pressure compared to bare foot walking. Gait asymmetry analysis illustrated more even medial midfoot contact area during 3DP-HAFO walking compared to bare foot walking while A-AFO walking did not. In QUEST survey, 3DP-HAFO outweighs A-AFO in fitting and durableness. Conclusions3DP-HAFO may improve ankle instability and gait asymmetry in chronic stroke patients.


2011 ◽  
Vol 8 (3-4) ◽  
pp. 377-384 ◽  
Author(s):  
Jungyoon Kim ◽  
Sungjae Hwang ◽  
Ryanghee Sohn ◽  
Younghee Lee ◽  
Youngho Kim

We developed an active ankle-foot orthosis (AAFO) that controls dorsiflexion/plantarflexion of the ankle joint to prevent foot drop and toe drag during hemiplegic walking. To prevent foot slap after initial contact, the ankle joint must remain active to minimize forefoot collision against the ground. During late stance, the ankle joint must also remain active to provide toe clearance and to aid with push-off. We implemented a series elastic actuator in our AAFO to induce ankle dorsiflexion/plantarflexion. The activator was controlled by signals from force sensing register (FSR) sensors that detected gait events. Three dimensional gait analyses were performed for three hemiplegic patients under three different gait conditions: gait without AFO (NAFO), gait with a conventional hinged AFO that did not control the ankle joint (HAFO), and gait with the newly-developed AFO (AAFO). Our results demonstrate that our newly-developed AAFO not only prevents foot drop by inducing plantarflexion during loading response, but also prevents toe drag by facilitating plantarflexion during pre-swing and dorsiflexion during swing phase, leading to improvement in most temporal-spatial parameters. However, only three hemiplegic patients were included in this gait analysis. Studies including more subjects will be required to evaluate the functionality of our newly developed AAFO.


2014 ◽  
Vol 39 (2) ◽  
pp. 140-149 ◽  
Author(s):  
Sumiko Yamamoto ◽  
Setsuro Ibayashi ◽  
Masako Fuchi ◽  
Tadashi Yasui

Background:An ankle–foot orthosis using an oil damper is designed to enable natural movement of the ankle joint. Wearing an ankle–foot orthosis using an oil damper has been demonstrated to assist the first rocker in stroke patients, but its effect on their gait when not wearing it is unclear.Objectives:To determine the effect of use of ankle–foot orthosis using an oil damper on the gait of stroke patients with hemiparesis when not wearing the ankle–foot orthosis.Study design:Crossover study.Methods:The gait of eight stroke patients in the chronic phase when not wearing an ankle–foot orthosis was measured, using a three-dimensional motion analysis system, before using the ankle–foot orthosis using an oil damper and then without and with using the ankle–foot orthosis using an oil damper after 3 weeks of use. Differences in gait were compared between the three measurement conditions.Results:Use of ankle–foot orthosis using an oil damper significantly decreased preswing time and significantly increased the positive ankle joint power in stance when not wearing the ankle–foot orthosis using an oil damper.Conclusions:These changes indicate the promising therapeutic effects of ankle–foot orthosis using an oil damper use and suggest the ankle–foot orthosis using an oil damper’s potential as a therapeutic device.Clinical relevanceAfter 3 weeks of use of an ankle–foot orthosis using an oil damper, which assists the first rocker, the gait of stroke patients in the chronic phase when not wearing the ankle–foot orthosis using an oil damper was improved. Preswing time was significantly decreased and positive ankle joint power was significantly increased. The ankle–foot orthosis using an oil damper, which assists the first rocker function with natural movement of the ankle joint during gait, has the potential to improve the gait of stroke patients after immediate-term use.


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