Preliminary Assessment of a Postural Synergy-Based Exoskeleton for Post-Stroke Upper Limb Rehabilitation

Abstract

Upper limb exoskeletons have drawn significant attention in neurorehabilitation because of the anthropomorphic mechanical structure analogous to human anatomy. Whereas, the training movements are typically unorganized because most exoskeletons ignore the natural movement characteristic of human upper limbs, particularly inter-joint postural synergy. This paper introduces a newly developed exoskeleton (Armule) for upper limb rehabilitation with a postural synergy design concept, which can reproduce activities of daily living (ADL) motion with the characteristics of human natural movements. The semitransparent active control strategy with the interactive force guidance and visual feedback ensured the active participation of users. Eight participants with hemiplegia due to a first-ever, unilateral stroke were recruited and included. They participated in exoskeleton therapy sessions for 4 weeks, with passive/active training under trajectories and postures with the characteristics of human natural movements. The primary outcome was the Fugl-Meyer Assessment for Upper Extremities (FMA-UE). The secondary outcomes were the Action Research Arm Test(ARAT), modified Barthel Index (mBI), and metric measured with the exoskeleton After the 4-weeks intervention, all subjects showed significant improvements in the following clinical measures: the FMA-UE (difference, 11.50 points, p=0.002), the ARAT (difference, 7.75 points p<0.001), and the mBI (difference, 17.50 points, p=0.003) score. Besides, all subjects showed significant improvements in kinematic and interaction force metrics measured with the exoskeleton. These preliminary results demonstrate that the Armule exoskeleton could improve individuals' motor control and ADL function after stroke, which might be associated with kinematic and interaction force optimization and postural synergy modification during functional tasks.

Design methodology of portable upper limb exoskeletons for people with strokes

“…The English national quality standard states that stroke patients must be given a minimum of 45 min of each necessary therapy, at least 5 days a week. The vast majority of rehabilitation strategies for exoskeleton follow this standard, such as He et al ( 2021 ), the participants underwent task-specific training involving 5-DoFs upper extremity movements in a three-dimensional environment with the aid of an exoskeleton for 45 min per day, 5 days per week, for 4 weeks (total of 20 sessions). In every session, the participants were required to complete two sets of exercises.…”

Analysis of Exoskeleton Suit in Clinical and Home Use

“…Spinal cord injury (SCI) and stroke are two major neurological diseases that cause motor disorders of the upper and lower extremities, and the mobility of limbs varies according to the degree of injuries. Although some muscles may still function in some ways, this does not necessarily mean that they have direct control over the limb, which can limit activities of daily living (ADL) [1,2]. Extremity disability will severely affect the autonomy and quality of life as well as burden families and society [2].…”

“…Although some muscles may still function in some ways, this does not necessarily mean that they have direct control over the limb, which can limit activities of daily living (ADL) [1,2]. Extremity disability will severely affect the autonomy and quality of life as well as burden families and society [2]. It has been demonstrated that beginning inpatient rehabilitation interventions as soon as the injury occurs will make them more conducive to comprehensive functional recovery [1].…”

Automatic Upper-Limb Brunnstrom Recovery Stage Evaluation via Daily Activity Monitoring

“…S TROKE is one of the leading causes of death and disability, with approximately 42.4 million cases occurring worldwide each year [1]. One common clinical manifestation of stroke survivors is hemiplegia [2], which greatly affects their performance in activities of daily living (ADLs) and brings a heavy burden to their families [3]. Post-stroke rehabilitation is an effective way to improve the ADLs performance [4].…”