A tailor-made hand orthosis for patients with ALS to support eating and drinking independently

Abstract

Introduction
This project is about designing a tailor-made hand orthosis for hand support of patients with Amyotrophic Lateral Sclerosis (ALS) -Limb onset to increase independence during desired activities. According to the National Institute of Neurological Disorders and Stroke (2014), ALS, is a progressive neurodegenerative disease which attacks motor neurons in the brain and spinal cord. This results in the wasting away of muscles, by which they are weakened. Patients gradually lose the ability to move, speak, swallow, and, eventually, to breathe unaided within an average of two to four years after the onset of the symptoms (Andersen, P. M., Abrahams, S., Borasio, G. D., de Carvalho, M., Chio, A., Van Damme, P., Weber, M. (2012).
Discover
According to the ALS Association (n.d.), ALS limb onset starts with distal muscle weakness (further away from the heart) and gradually move in the proximal direction (closer to the heart). This means that in most cases, finger strength is lost before weakness in the wrist appears, which is followed by loss of power in the arm. This study starts by evaluating if an arm balancing exoskeleton contributes to performing activities of daily living (ALDs) for ALS patients. However, not being able to control hand movement causes patients not being able to perform essential ALDs. An arm exoskeleton which lacks hand support will not contribute.
Prominent problem
Patients become highly dependent on the care of informal caregivers and assistive aids, which is emotionally and mentally burdensome for both. When patients can perform small tasks like ADLs themselves with assistive aids, it will contribute to the level of independence and unburden the informal caregivers. This study aims to investigate the most prominent problems occurring in the daily life of patients by interviewing four patients. It is found that patients primary prefer to complete dining activities independently because of alleviating their informal caregivers and avoiding home care during these valued times.
Develop
Based on this insight, exploration research is done to find the best way on how to support ALS patients during dining activities. The activity is detailly analysed by dividing dining into smaller actions, which presents the underlying problems. This shows that grasping objects is the first problem which limits patients. A second study compares the applicability of three types of hand support which solve grasp failure: active (dynamic) support, hybrid support, and static support are researched. These supports are discussed with patients and medical experts. The type of support which is operated by patients in the simplest way regarding basic movements and straightforward controlling is chosen to continue for further development. ALS patients can longer operate this type of support, and use this assistive aid immediately without long learning time.
Deliver
A tailor-made static hand orthosis is developed, which provides independence to ALS patients during dining activities. By automatically connecting and releasing to frequently used tableware, no strength of their fingers is required. The orthosis contributes to the level of comfort and addresses the individual differences for patients because it is tailor-made. The orthosis connects to frequently used objects by using a designed connector with magnetic capabilities and a mechanical lock.
Evaluate
This first iteration is evaluated by an ALS patient having mild paralysis in hand. The orthosis is tested while consuming breakfast consisting of fluid and food intake. The orthosis connects well with frequently used objects and operates straightforwardly and simply, which results in performing the dining activities with more independence and ease. Secondly, the results of the study are evaluated with an occupational therapist who agrees that this assistive aid could increase the level of independence for ALS patients. This first iteration can form a base for further development. Still, many iteration steps combined with user tests should follow. The first step would consist of improving the usability of the current connection to cups and other utensils like a fork and a knife.