Prototype Of Orthosis Research Articles

Neck orthosis design for 3D printing with user enhanced comfort features

An area of interest in orthopaedics is the development of efficient customized neck orthoses, considered that pathologies which affect the neck area are widespread. Advanced acquisition and modelling approaches combined with Additive Manufacturing (AM) can potentially provide customized orthoses with improved performance and complexity. However, in the design of these devices, besides functional and structural requirements, benefit and comfort of the patient should be a main concern, in particular, at the early stage of design during the acquisition of the body’s part, and while using the printed orthosis. In this paper, a scanning system with three sensors was developed which allows a fast, about 5 s, and accurate acquisition of the neck area with minimum discomfort for the patient. A neck orthosis with a ventilation pattern obtained by Topology Optimization (TO), lightened by about 35%, was also established. In fact, a main role for comfort is played by the ventilation pattern which contributes both to lightness and breathability. Its structural and comfort performance was evaluated in comparison with an orthosis with a ventilation pattern configured by Voronoi cells. Structural assessment was carried out by means of finite element analysis under main loading conditions. An evaluation of neck temperatures in relation to wearing 3D printed prototypes, manufactured with Hemp Bio-Plastic® filament, was finally conducted by means of a thermal imaging camera. TO orthosis prototype showed a better performance regarding thermal comfort, with a maximum increase of neck temperature less than 1 °C, which makes the proposed configuration very promising for user's comfort.

Development of a robotic orthosis for fingers flexion motion by surface myoelectric control: Open source prototype

Objective:This study proposed an open-source myoelectric robotic hand orthosis prototype to support people with neuromuscular disorders in performing activities of daily living (ADLs). Methods:A user-tuned methodology was applied, designing the system’s usability and ergonomics with recommendations in literature (2017 to 2020), thus calibrating the prototype by user’s metrics. It has two modules: transmitter–interpreter system (TIS) and receiver–actuator system (RAS) that performs three hand pose: (i) pulp pinch, (ii) cylindrical grip, and (iii) resting hand. The system uses a linear discriminant analysis (LDA) classifier with real-time disruptive windowing (80 ms) and a majority vote algorithm (n=3) as post-processing. TIS classifies and transmits a hand pose within 300 ms to RAS, which executes the hand pose. Results:The LDA classifier was trained with ten datasets of surface myoelectric signals (sMES) recorded from a healthy volunteer. The system’s accuracy reached 90% in real-time tests with three everyday objects. Splints were 3D-printed with resistant material, so the fitting and range of motion were comfortable for the volunteer. Conclusion:The prototype achieved the recommendations in the literature, and it was the orthosis that most fulfilled said requirements compared to state-of-the-art (2017 to 2020) myoelectric robotic hand orthosis. However, it only assists with finger flexion. Significance:The open-source format provides other researchers a starting point to develop an orthosis for in-home rehabilitation that actively assists in ADLs. Additionally, production costs for the orthosis are R$856.35, or 2.98% of the cheapest myoelectric hand orthosis available on the market (PowerGrip), both quoted on November 2021.

Proposal for the design and manufacture of a dynamic orthoses prototype for hand rehabilitation

Objetivos The objective of this research is to propose a prototype design of the dynamic orthosis adaptation system for hand rehabilitation. For this, the following methodology was used: the biomechanical and architectural foundations and the functional patterns of the fingers of the hands were previously analyzed, later the test subject was chosen and the corresponding measurements were taken, to finalize the design and manufacture of the prototype. The dynamic orthosis prototype proposed in this research is controlled by servomotors coupled to rings with rigid links, which transmit movement at a certain speed, from the motor axis to the fingers, simulating the biomechanical movements of flexion and extension. The design of this device is focused on users who do not have movement in the phalanges, and thus prevent their muscles from atrophying. The contribution of this research is the development of an economic device that can partially or totally replace the physiological therapies of a patient with problems in the upper limb (hand).

Finite Element Analysis and Fabrication of Voronoi Perforated Wrist Hand Orthosis Based on Reverse Engineering Modelling Method

Other than surgery, post-stroke spasticity, fractures due to accidents, sports injuries, and musculoskeletal disorders due to office work on the wrist can be treated using a wrist-hand orthosis. The customized conventional methods usually have some drawbacks, which are more expensive, take a long time to manufacture, and require expert skills from medical therapists. The presence of reverse engineering (RE) technology can be applied in the medical field, such as the manufacture of prosthetic or orthosis devices. This study aims to develop a reverse engineering-based wrist-hand orthosis design, analyze it using the finite element method, and fabricate it. Research methods included 3D scanning, CAD modelling, model analysis, 3D printing, and postprocessing. The model material used was PLA with variations in the thickness of 5 mm, 5.5 mm, and 6 mm, and the load values range from 0 N to 30 N. The results of the equivalent stress analysis showed that the 5 mm thickness model could withstand a load of 30 N with a maximum equivalent stress of 23.46 MPa. With a safety factor value of 2.56, it was still relatively safe, and a critical area was at the back end of the model's palm between the thumb and index finger. The equivalent elastic strain and deformation results also had the same graphic trend with the maximum values for the same model, which were 0.0076 mm and 0.614 mm, respectively. The 3D printing FDM result showed that the Voronoi perforated wrist-hand orthosis prototype was sturdy, fit, and comfortable. It is expected to hold muscle tone and immobilize for hand rehabilitation.

Solution of the contact task of the elbow orthosis prototype

Over the past two decades, upper limb exoskeletons used for service delivery and rehabilitation have attracted attention from the biomedical and engineering sectors. Technology is becoming one of the key solutions for physically weak or disabled people. Mechanical devices were developed to improve the performance and strength of the user. Devices that help the patient during postoperative or post-traumatic rehabilitation after joint damage of various types are orthoses. There are different types of orthoses, such as mechanical, active with EMG functions, exoskeletons, and others. In this work, an overview of various types of orthoses is given, problems of fixing orthoses elements are considered. In the review of the literature related to these studies, the advantages and disadvantages of bolted connections are given. Two contact problems of the orthosis were also considered and the stress-strain state of the bolted joint of the structural elements of the elbow orthosis prototype under study was determined using the FEMAP with NASTRAN software package. Based on the necessary operating conditions, a prototype model of the orthosis was presented.

DETERMINATION OF THE STRESS-STRAIN STATE OF THE STRUCTURAL ELEMENTS OF THE ELBOW ORTHOSIS PROTOTYPE

Rehabilitation of patients should not be limited only to the time of intensive treatment in the hospital, but also to therapy in the following stages, especially during daily activities, if the patient’s condition requires it. Such devices that help the patient during postoperative or post-traumatic rehabilitation after joint damage are orthoses. This paper provides an overview of various types of orthoses, selects material for structural elements of the orthosis, and determines the stress-strain state of the sample under study. Also, based on the necessary operating conditions, the engine and bevel gear are selected. The model of the orthosis prototype is presented and the stress-strain state of the structural elements of the elbow orthosis prototype is determined.

Semiactive Knee Orthotic Using a MR Damper and a Smart Insole to Control the Damping Force Sensing the Plantar Pressure.

This work presents the development of semiactive knee orthosis prototype that focus to absorb the forces and impacts in this joint during the human gait. This prototype consists of three subsystems: the first is a wireless and portable system capable of measuring the ground reaction forces in the stance phase of the gait cycle, by means of an instrumented insole with force sensing resistors strategically placed on the sole of the foot, an electronic device allows processing and transmit this information via Bluetooth to the control system. The second is a semiactive actuator, which has inside a magnetorheological fluid, highlighting its ability to modify its damping force depending on the intensity of the magnetic field that circulates through the MR fluid. It is regulated by a Proportional Derivative (PD) controller system according to the values of plantar pressure measured by the insole. The third component is a mechanical structure manufactured by 3D printing, which adapts to the morphology of the human leg. This exoskeleton is designed to support the forces on the knee controlling the action of the magnetorheological actuator by ground reaction forces. The purpose of this assistance system is to reduce the forces applied to the knee during the gait cycle, providing support and stability to this joint. The obtained experimental results indicate that the device fulfills the function by reducing 12 % of the impact forces on the user's knee.

Design, implementation, and evaluation of a backstepping control algorithm for an active ankle–foot orthosis

Active ankle–foot orthoses are used to assist patients suffering from stroke, multiple sclerosis, cerebral palsy etc. through providing them an external force supply to track normal gait cycles. In this paper, an active ankle–foot orthosis prototype is developed and an adaptive backstepping control algorithm is proposed for tracking desired gait trajectories while reducing the effects of unknown disturbances. A prototype of the orthosis, which is composed of a series elastic actuator, a lever mechanism and an orthotic shoe, is developed. The prototype is mathematically modeled as a two-degree-of-freedom mass–spring system. The unknown disturbances are modeled as a finite sum of sinusoidal signals with unknown amplitudes, frequencies and phases, and an unknown constant. The backstepping control algorithm is designed for the force input supplied to the system, and the stability of the equilibrium point is proved. The proposed algorithm is implemented in a real-time operating system to control the developed ankle–foot orthosis prototype. Numerical simulations and physical experiments on healthy human subjects are performed to show the superiority of the proposed design over a PID controller in trajectory tracking of the prototype. As a further development, an embedded system is designed to bring portability to the ankle–foot orthosis prototype. Experiments are performed to observe the execution performance and power consumption of the embedded system.

Orthotic prototype for upper limb printed in 3D: A efficient solution

Traditionally a limb that has suffered a fracture, rupture or dislocation is immobilized with plaster, a procedure that generates discomfort in the patient to take a shower, besides producing excessive itching and sweating, stimulating the growth of the bacteria and leading to an odorous form, unhygienic and difficult to keep clean of treatment. On the other hand, if the plaster remains for a long period, it can cause injuries in joints and ligaments. This project describes a methodology of manufacturing a prototype of orthosis for upper limb printed in 3D, through additive manufacturing and reverse engineering, technology that is presented as an excellent alternative to solve the problems of traditional plaster molds. The model of the orthosis is obtained through the Meshmixer software and the structural viability of the design is studied using methods of finite element analysis and biomimetics, to guarantee the best possible mechanical properties. The realization of this work provides a custom-made prototype orthosis, a more comfortable, hygienic and aesthetically pleasing solution, which in turn allows the reduction of the time of use of the plaster molds.

First prototype of EMG-controlled power hand orthosis for restoring hand extension in stroke patients.

Weakness in finger extensors is a common post-stroke deficit that can disturb hand functioning. Despite introducing several powered hand orthoses in literature, most of these devices focused on providing finger flexion. There is a little consideration for providing active hand extension in stroke patients. Moreover, in many devices, the finger extensions were restored passively by spring component. In this study, a new Electromyography (EMG)-controlled powered hand orthosis was designed to improve hand function by restoring and training hand extension in stroke patients with paretic hand. This orthosis was a glove-like device that was developed from two mechanical and electrical sections. After construction and verifying of the orthosis, its applicability was tested on two patients with Cerebrovascular accident (1 woman and 1 man) with paretic hands in an 18-session therapeutic approach. To evaluate the effectiveness of orthosis, Wolf Motor Function Test and Box and Block test were conducted before and after the training sessions. The primary assessment of the prototype was conducted on a healthy subject and three stroke patients. These evaluations showed that the new powered hand orthosis could be effective for finger extension task and training. Furthermore, after the 18-session training approach, significant improvements were seen in the scores of both Wolf and Box and Block tests. The preliminary findings suggested that the first prototype of orthosis could provide a desirable function for stroke patients with paretic hand. Moreover, it could be used as a training device in the rehabilitation of these patients.

Prototype of specific hydraulic acting orthosis in recovery standing and walking in stroke patients

Our research highlight the utility of specific devices to enhance the performances of orthostatism and walking in patients with stroke. The configuration of the orthosis skeleton, based on composite glass fiber, allows the adjustment of the dimensions and anatomical fit of the patient's lower limb by a telescopic system to make it as ergonomic as possible. The control is achieved by three hydraulic distributors powered by a miniature pump. Feedback from the level of the orthosis joints corresponding to human ones is ensured by three resistive potentiometric transducers. We corrected the posture of the foot, the equine and the muscular imbalance caused by the spasticity. The prototype testing will follow the bioethics rules in volunteer patients by analyzing the following parameters: modified Ashworth scale for spasticity, Tinetti balance and walking scales. The orthosis achieved the maximum compaction of the available components for the best functionality. For this purpose the support frame is made of composite material based on glass fiber, and the actuators are hydraulic, providing maximum force at the proposed gauge. The power supply of the system in this phase is made from the 220 V AC with a power about of 100 W for normal walking on flat ground. An autonomy of several hours is expected. Although the movement is made on a flat ground, but orthosis allows the assisting for climbing and down stairs. This prototype of orthosis could be the future in rehabilitation of walking in the stroke patient, and it has the capacity to be extend to the other lower limb for paraparetic patients.

A new concept of orthosis for correcting fingers ulnar deviation

Introduction Rheumatoid arthritis (RA) is a chronic, multisystem disease that involves synovial inflammation, leading to deformities, like finger ulnar deviation, pain and functional difficulties. The conservative treatment comprises orthoses, features added to the body that aims to correct deformity, reduce pain and improve functionality. In the market there are few kinetic/mobile orthosis models for correction of ulnar deviation in the fingers. However, users usually complain about increased palmar volume, presence of pressure points and functional loss, demonstrating the necessity to develop more effective orthoses. In this paper we introduce an innovative concept, of an original and articulate dynamic/kinetics orthosis, which aims to correct this finger deformity and encourage functionality. Methods Methodological procedures were divided into: Need Recognition; Specification Concept; Prototype and Validation. This paper deals with the last two stages of this research. Results A virtual orthosis prototype using CAD Solid Edge Insight™ was proposed. The orthosis developed consisted of 10 pieces, made of metal and resin with carbon fiber. Conclusion After virtual movement simulation, it was verified that the prototype allows for wrist and finger flexion/extension, the possibility of bilateral use, and provids ulnar deviation correction for the fingers. The final product is innovative and is easy to put on/off; volunteers claimed that the new prototype was satisfactory in terms of deformity correction.

Assessment of a shoulder orthosis prototype setting the upper limb in a functional posture: A single case report

The shoulder is painful in 70% of post-stroke patients. Sling and shoulder orthosis are important for medical care. However, series slings have not proved efficiency to improve upper limb function. We realize (with OCTO31 company) a custom-made shoulder orthosis prototype (EO31) to set the upper limb in a posture with an elbow flexion, a forearm supination and, by the way, a finger extension. The objective is to facilitate the upper limb function and to decrease shoulder pain. A 54-year-old female, 6-month post ischemic left stroke, with shoulder pain (diastasis) recovers a distal motor function with both pinch and grasp. She under-uses this recovery, due to proximal weakness with impossibility to obtain a functional position of the forearm. Patient has used the EO31 prototype daily for 30 days. Assessments are performed with prototype compared to standard shoulder orthosis (Ottobock ® Shoulder support 7126). Functional assessment (Wolf Motor Function Test and Chedoke Arm and Harm Activity Inventory) do not show significant difference (neither ability to perform tasks or speed) between the two orthosis. Quebec User Evaluation of Satisfaction with assistive Technology (QUEST) is a lot better with EO31 (31/35) compare to standard orthosis (14/35). Shoulder pain slightly decreases with EO31. This custom-made shoulder orthosis setting the upper limb in a functional posture improves comfort and patient's satisfaction. This improves significantly safety and observance. After a month of use, we were unable to prove the functional benefits of the prototype compare to a standard orthosis, probably due to functional improvement and motor recovery of the patient. This prototype will now be used with other patients, with early comparative assessment to confirm our results and better define functional benefits.

Design and performance characterization of a hand orthosis prototype to aid activities of daily living in a post-stroke population.

This paper presents the design of a hand orthosis prototype intended to assist persons with hand paresis, as a result of stroke, perform activities of daily living. Among its attributes, the orthosis is characterized by a low mass and small profile, while still offering the power assistance of a robotic exoskeleton. Experimental characterization of the orthosis is presented, including its mass, envelope dimensions, motion bandwidth, and joint torque characteristics.

Characterization of a Pneumatic Artificial Muscle for its application in an Active Ankle-Foot Orthosis

The training of lower limbs with robotic exoskeletons or active orthoses has proven to be an effective tool to help patients with various types of neurological movement disorders, to recover their functional ambulation capacity. A key component to achieve this purpose is the type of active element used to compensate for muscle weakness, typically observed in such locomotor disorders. Based on these considerations, this paper presents the results of an experimental test developed for calibration, tuning and behavioral identification of a commercial pneumatic artificial muscle Festo®, with view to its application as active element of an active ankle – foot orthosis prototype for human gait rehabilitation. It is expected that such prototype would enable to recover the ankle joint function in patients with Myelomeningocele. The actuator performance analysis from the achieved tests, as well as the study of gait patterns in persons with Myelomeningocele, evidence the potentiality of this actuator as an active element of a robotic exoskeleton applied to human gait rehabilitation.

Exploiting joint synergy for actuation in a lower‐limb active orthosis

PurposeLower‐limb exoskeletons and powered orthoses are external devices that assist patients with locomotive disorders to achieve correct limb movements. Current batteries cannot meet the long‐term power requirements for these devices, which operate for long periods of time. This issue has become a major challenge in the development of these portable robots. Conversely, legged locomotion in animals and humans is efficient; to emulate this behaviour, biomimetic actuation has been designed attempting to incorporate elements that resemble biological elements, such as tendons and muscles, in the mechanical systems. The purpose of this paper is to present a mechanism that resembles a human tendon to achieve and utilise the synergic actuation of the leg joints.Design/methodology/approachIn this paper, we present a mechanism that resembles a human tendon to move the ankle joint and utilise the synergic actuation of hip and knee joints. Implementation of the proposed transmission system in the ATLAS active orthosis prototype allowed for a better ankle gait fit, which resulted in a more natural stride and, as expected, optimised energy consumption in the locomotion cycle and actuation energy requirements.FindingsThe fitted passive ankle motion provides toe‐off impulse, increases support force, and helps provide ground clearance.Originality/valueA synergetic underactuated movement in the ankle joint, implemented by two cables in each leg, improves the functionality of the device without increasing the leg weight and while maintaining a reduced size. To achieve a correct and efficient motion in the ankle of an active orthosis, two steel cables were attached in the ATLAS orthosis. These cables act as a synergic biarticular linkage and transfer motion from the hip and knee joints. Synergic ankle motion provides impulse in the toe‐off, increases support force, and provides ground clearance. These goals are achieved with low energy expenditure because of synergical actuation, and high inertia is prevented in the more distal limb.

A combined robotic and cognitive training for locomotor rehabilitation: evidences of cerebral functional reorganization in two chronic traumatic brain injured patients

It has been demonstrated that automated locomotor training can improve walking capabilities in spinal cord-injured subjects but its effectiveness on brain damaged patients has not been well established. A possible explanation of the discordant results on the efficacy of robotic training in patients with cerebral lesions could be that these patients, besides stimulation of physiological motor patterns through passive leg movements, also need to train the cognitive aspects of motor control. Indeed, another way to stimulate cerebral motor areas in paretic patients is to use the cognitive function of motor imagery. A promising possibility is thus to combine sensorimotor training with the use of motor imagery. The aim of this paper is to assess changes in brain activations after a combined sensorimotor and cognitive training for gait rehabilitation. The protocol consisted of the integrated use of a robotic gait orthosis prototype with locomotor imagery tasks. Assessment was conducted on two patients with chronic traumatic brain injury and major gait impairments, using functional magnetic resonance imaging. Physiatric functional scales were used to assess clinical outcomes. Results showed greater activation post-training in the sensorimotor and supplementary motor cortices, as well as enhanced functional connectivity within the motor network. Improvements in balance and, to a lesser extent, in gait outcomes were also found.

Analysis, Design and Development of a Carbon Fibre Reinforced Plastic Knee-Ankle-Foot Orthosis Prototype for Myopathic Patients

A traditional knee-ankle-foot orthosis (KAFO) for myopathic patients has been studied for the assessment of loads and fatigue resistance. Starting from this basis a thermoplastic matrix carbon fibre reinforced plastic composite (CFRP) KAFO has been developed in order to reduce the weight. A finite-element simulation programme for deformation analysis was used to compare the behaviour of conventional and CFRP orthosis. There were no breakages either of the prototype or of its parts. The CFRP orthosis allows a weight reduction of more than 40 per cent.