Feasibility of a second iteration wrist and hand supported training system for self-administered training at home in chronic stroke

Telerehabilitation allows continued rehabilitation at home after discharge. The use of rehabilitation technology supporting wrist and hand movements within a motivational gaming environment could enable patients to train independently and ultimately serve as a way to increase the dosage of practice. This has been previously examined in the European SCRIPT project using a first prototype, showing potential feasibility, although several usability issues needed further attention. The current study examined feasibility and clinical changes of a second iteration training system, involving an updated wrist and hand supporting orthosis and larger variety of games with respect to the first iteration. Nine chronic stroke patients with impaired arm and hand function were recruited to use the training system at home for six weeks. Evaluation of feasibility and arm and hand function were assessed before and after training. Median weekly training duration was 113 minutes. Participants accepted the six weeks of training (median Intrinsic Motivation Inventory = 4.4 points and median System Usability Scale = 73%). After training, significant improvements were found for the Fugl Meyer assessment, Action Research Arm Test and self-perceived amount of arm and hand use in daily life. These findings indicate that technology-supported arm and hand training can be a promising tool for self-administered practice at home after stroke.Final Accepted Versio

Desain dan Analisis Elemen Hingga Model Wrist Hand Orthosis Berbasis Metode Pemodelan Reverse Engineering

Salah satu treatment untuk spasticity efek pasca stroke, fracture karena kecelakaan, injury karena cedera olahraga, dan musculoskeletal disorders karena pekerjaan kantoran pada pergelangan tangan selain dengan operasi yaitu dengan penggunaan wrist hand orthosis. Umumnya pembuatan medical device tersebut menggunakan metode konvensional yang mempunyai kekurangan. Hadirnya teknologi reverse engineering (RE) dapat diaplikasikan dalam bidang medis seperti pembuatan alat prosthetic atau orthosis. Pada penelitian ini bertujuan untuk mengembangkan desain wrist hand orthosis berbasis reverse engineering dan menganalisisnya menggunakan metode elemen hingga. Metode penelitian meliputi 3D scanning, CAD modelling, model analysis, dan post processing. Material model yang digunakan adalah ABS dengan variasi ketebalan 5 mm, 6 mm, dan 7 mm, serta besar nilai pembebanan mulai dari 5 N sampai 25 N. Hasil analisis equivalent stress menunjukkan model ketebalan 5 mm mampu menahan load 25 N dengan maximum equivalent stress sebesar 13.52 MPa yang masih tergolong aman dengan nilai safety factor 2.11 dengan area kritis di ujung punggung telapak tangan model antara ibu jari dan jari telunjuk. Hasil equivalent elastic strain dan deformation juga mempunyai tren grafik yang sama dengan nilai maximum pada model ketebalan 5 mm yaitu masing-masing sebesar 0.0057 mm dan 0.616 mm. Dari hasil analisis tersebut dapat disimpulkan bahwa model wrist hand orthosis berlubang voronoi yang memiliki bentuk seperti surface tangan manusia dengan ketebalan minimalis 5 mm mampu bekerja dengan baik memfiksasi tangan pasien untuk proses rehabilitasi

Preliminary test of a functional hand orthosis prototype

A prescrição, projeto, fabricação, verificação e treino de órteses fazem parte das intervenções utilizadas pelo terapeuta ocupacional com indivíduos apresentando disfunções físicas, com objetivo de recuperar a função e melhorar o desempenho ocupacional. Porém, o uso de órteses em pacientes com déficits crônicos em mão e punho, como ocorre nas lesões do plexo braquial, lesões medulares, doenças neurológicas e degenerativas, se apresenta como um grande desafio. Este trabalho teve o objetivo de descrever o protótipo de um novo modelo de órtese funcional para mão, conhecida como Luva Funcional, e os resultados dos testes preliminares. Foi realizado um estudo exploratório, dividido em três fases. Na primeira fase foi verificado o funcionamento da parte biomecânica da órtese; na segunda fase, o funcionamento do circuito de interpretação do sinal mioelétrico; e, na terceira fase, o funcionamento de todo o sistema que compreende a órtese. Os resultados se mostraram satisfatórios, demonstrando o adequado funcionamento da Luva Funcional, bem como sua capacidade de segurar objetos através do comando realizado por meio de sinais mioelétricos. Conclui-se que a Luva Funcional tem o potencial de auxiliar indivíduos com paralisias em mão e punho, melhorando seu desempenho ocupacional. _________________________________________________________________________________________ ABSTRACTThe prescription, design, fabrication, testing and training of orthotic devices are common part of interventions for occupational therapist with physically disabled individuals, with the objective of regaining function and improving occupational performance. However, orthosis for patients with chronic deficits in hand and wrist, as occurs in brachial plexus injuries, spinal cord injuries, and degenerative neurological diseases, is presented as a challenge. This work has the objective to describe the prototype of a new model of functional hand orthosis, known as Functional Glove, and the results of preliminary tests. It was conducted an exploratory study, shared into three phases. In the first phase, it was tested the operation of the biomechanics orthosis part, in the second phase, it was tested the circuit by means of myoelectrical signal, and the third phase, the operation of the entire system of orthosis. The results were satisfactory, demonstrating the proper operation of the Functional Glove as well as its ability to hold objects through the command performed by means of myoelectrical signals. We conclude that Functional Glove has the potential to assist individuals with paralysis in the hand and wrist, improving occupational performance

Design a hand orthosis to aid post-stroke patients with hemiplegia

Abstract—Stroke is the third cause of all disabilities for people over 25 years old. Indeed, the percentage of people who suffer from hemiplegia after stroke is higher than 75%. Patients with hemiplegia have considerable difficulty performing activities of daily living, such as feeding or grasping objects. Assistive devices for stroke patients have been developing since a very long time ago; however, some of them are not well accepted by patients because they are not comfortable, wearable, portable, lightweight and useful. This research presents the first version of the design of dynamic orthosis to aid post-stroke patients with hemiplegia to grasp cylindrical and spherical objects. The proposed orthosis was designed by using a cyclic design methodology called Iterative Design which is used for continuous product improvement; moreover, this paper presents a detailed description of the control algorithm and the electromechanical design in which a flexible power transmission element was introduced to perform the opening and closing of the hand. Then, a motion study was performed to determine the range of motion (ROM) of the orthosis. Results show that the orthosis is able to cover 88.8% of the ROM of the metacarpophalangeal (MCP) joint and 72.7% of the ROM of the proximal interphalangeal (PIP) joint. These results indicate that the hand orthosis can assist patients in performing grasping tasks. In addition, the main feature of this orthosis is ergonomic because it was designed using anthropometric measurements of the hand. Other features of the orthosis are lightweight (230 g), portable and easy to use. Index Terms—stroke, hemiplegia, assistive device, hand ortho- sis, dynamic orthoses, static orthoses

A data-driven method to reduce excessive contact pressure of hand orthosis using a soft sensor skin

Discomfort under customised hand orthosis has been commonly reported in clinics due to excessive contact pressures, leading to low patient adherence and decreased effectiveness of orthosis. However, the current orthosis adjustment by clinicians to reduce pressures based upon subjective feedback from patients is inefficient and prone to variability. Therefore, a quantitative method to guide orthosis adjustment was proposed here by developing a data-driven method. Firstly, Verbal Protocol Analysis was employed to convert the implicit process of orthosis customisation into working models of clinicians. Relevant data to inform a new solution development to reduce excessive contact pressure were extracted from the working models in terms of time consumption and iterations of tasks. Secondly, a new soft sensor skin with strategically placed sensing units to measure static contact pressures under hand orthoses was developed. Finite element simulations were conducted to reveal the required contact pressure range (0.02 – 0.078 MPa) and the distribution of relatively high pressures in 12 key areas. A new fabrication method was proposed to produce the sensor skin, which was then characterised and tested on the subject. The results show that the sensor unit has a pressure range from 0.01 MPa to 0.1 MPa with the maximum repeatability error of 6.4% at 0.014 MPa, and the maximum measurement error of 8.26% at 0.023 MPa. Thirdly, a new method was proposed to predict contact pressures associated with the moderate level of discomfort at critical spots under hand orthoses. 40 patients were recruited to collect contact pressures under two types of orthoses using the sensor skin, and their discomfort perceptions were measured with a categorical scale. Based on these data, artificial neural networks for five identified critical spots on the hand were built to predict pressure thresholds that clinicians can use to adjust orthoses, thus reducing excessive contact pressures. The neural networks show satisfactory prediction accuracy with R2 values over 0.89 of regression between network outputs and measurements. Collectively, this thesis proposed a novel method for clinicians to adjust orthoses quantitatively and reduce the need for subjective assessment for patients. It provided a platform to further investigate the pressure for patients with other conditions.Open Acces