Development of a biological signal-based evaluator for robot-assisted upper-limb rehabilitation: a pilot study

Bio-signal based assessment for upper-limb functions is an attractive technology for rehabilitation. In this work, an upper-limb function evaluator is developed based on biological signals, which could be used for selecting different robotic training protocols. Interaction force (IF) and participation level (PL, processed surface electromyography (sEMG) signals) are used as the key bio-signal inputs for the evaluator. Accordingly, a robot-based standardized performance testing (SPT) is developed to measure these key bio-signal data. Moreover, fuzzy logic is used to regulate biological signals, and a rules-based selector is then developed to select different training protocols. To the authors’ knowledge, studies focused on biological signal-based evaluator for selecting robotic training protocols, especially for robot-based bilateral rehabilitation, has not yet been reported in literature. The implementation of SPT and fuzzy logic to measure and process key bio-signal data with a rehabilitation robot system is the first of its kind. Five healthy participants were then recruited to test the performance of the SPT, fuzzy logic and evaluator in three different conditions (tasks). The results show: (1) the developed SPT has an ability to measure precise bio-signal data from participants; (2) the utilized fuzzy logic has an ability to process the measured data with the accuracy of 86.7% and 100% for the IF and PL respectively; and (3) the proposed evaluator has an ability to distinguish the intensity of biological signals and thus to select different robotic training protocols. The results from the proposed evaluator, and biological signals measured from healthy people could also be used to standardize the criteria to assess the results of stroke patients later

Caratteristiche delle sinergie muscolari dell'arto superiore, in soggetti sani e con diagnosi di ictus: revisione della letteratura

Background e obiettivi: L'impairment dell’arto superiore rappresenta, per l’incompletezza del recupero e l’impatto sulla qualità di vita che ne deriva, un aspetto di rilievo nei soggetti con diagnosi di ictus. Tuttavia, l’eterogeneità dei quadri motori ha da sempre rappresentato una difficoltà per lo sviluppo di evidenze della validità ed efficacia delle strategie fisioterapiche, probabilmente per un maggior focus della ricerca sugli effetti della riabilitazione a livello periferico, piuttosto che cercare di comprendere i meccanismi neurofisiologici centrali alla base del controllo motorio. In questo contesto si inserisce quindi il presente disegno di studio che, sostenendo l’ipotesi delle sinergie muscolari quale strategia del Sistema Nervoso Centrale per organizzare il movimento, ha come obiettivo di individuare le caratteristiche dei moduli motori nelle popolazioni con ictus e confrontarli con quelli registrati nei soggetti sani, al fine di individuare le eventuali alterazioni neurofisiologiche che un evento cerebrovascolare determina nell’organizzazione motoria dei movimenti volontari dell’arto superiore. Materiali e metodi: La presente tesi, redatta seguendo le linee guida PRISMA, fa riferimento al protocollo di revisione registrato su PROSPERO il 1 ottobre 2021 (ID: CRD42021275657). In particolare sono state consultate le seguenti banche dati: PubMed, CINAHL, Scopus, Web of Science, Cochrane ed Embase, dalle quali sono stati raccolti da due revisori indipendenti gli articoli che rispettassero i criteri di inclusione definiti a priori. In caso di disaccordo, un terzo revisore è intervenuto per prendere le decisioni finali. Una volta valutata l'inclusione degli studi, sono stati estratti e raccolti i dati in tabelle sinottiche. Risultati: Quarantotto studi sono stati analizzati per l'estrazione dei dati. Per ognuno di questi sono state raccolte le informazioni relative a campione, disegno di studio, definizione di sinergia muscolare, algoritmo di estrazione, numero e composizione dei moduli motori. Discussione e conclusioni: La mancanza di omogeneità rispetto alla definizione dei protocolli sperimentali ha reso i dati raccolti solo parzialmente confrontabili. Studi con caratteristiche affini hanno evidenziato sinergie quantitativamente simili in popolazioni con impairment motorio da lieve a moderato rispetto al gruppo di controllo sano. Risultati contrastanti sono invece emersi nei soggetti con disabilità di grado severo. Composizioni diverse sono state individuate nella maggior parte degli studi, per cui in termini di attivazioni muscolari non è stato possibile descrivere una valida panoramica dei moduli motori nei soggetti sani e con diagnosi di ictus.Background and objectives: Due to difficult in recovery and impact on quality of life, impairment of the upper limb represents the major issue in individuals diagnosed with stroke. However, heterogeneity of motor prognosis has always represented a difficulty for the development of valid and efficient physiotherapy strategies, probably due to a greater focus of research on the effects of rehabilitation at the peripheral level, rather than trying to understand the central neurophysiological mechanisms underlying motor control. This is the context for the present study design which, supporting the hypothesis of muscle synergies as a Central Nervous System strategy to organise movements, aims to identify the characteristics of motor modules in stroke populations and to compare them with those recorded in healthy subjects, in order to identify any neurophysiological alterations that a cerebrovascular event determines in motor control of voluntary movements of the upper limb. Materials and methods: This thesis followed the PRISMA guidelines and refers to the review protocol registered on PROSPERO on 1st October 2021 (ID: CRD42021275657). The following databases were consulted: PubMed, CINAHL, Scopus, Web of Science, Cochrane and Embase. Articles accomplishing defined inclusion criteria were screened by two independent reviewers. A third reviewer solved eventual disagreement. Data from included studies were extracted and collated in synoptic tables. Results: Forty-eight studies were analysed for data extraction. For each of these, information on sample, study design, definition of muscle synergy, extraction algorithm, number and composition of motor modules was extracted. Discussion and conclusions: The lack of homogeneity with respect to the definition of the experimental protocols made the collected data only partially comparable. Studies with similar characteristics showed quantitatively similar synergies in populations with mild to moderate motor impairment, compared with healthy control subjects. Conversely, contrasting results emerged in subjects with severe impairment. Different compositions were found in most of the studies, thus was not possible to describe a valid overview of the motor modules in healthy and stroke-diagnosed subjects at the level of muscle activations

Rehabilitation Engineering

Population ageing has major consequences and implications in all areas of our daily life as well as other important aspects, such as economic growth, savings, investment and consumption, labour markets, pensions, property and care from one generation to another. Additionally, health and related care, family composition and life-style, housing and migration are also affected. Given the rapid increase in the aging of the population and the further increase that is expected in the coming years, an important problem that has to be faced is the corresponding increase in chronic illness, disabilities, and loss of functional independence endemic to the elderly (WHO 2008). For this reason, novel methods of rehabilitation and care management are urgently needed. This book covers many rehabilitation support systems and robots developed for upper limbs, lower limbs as well as visually impaired condition. Other than upper limbs, the lower limb research works are also discussed like motorized foot rest for electric powered wheelchair and standing assistance device

Alterations in muscle activation patterns during robot-assisted bilateral training: A pilot study

Robot-assisted bilateral training is being developed as a new rehabilitation approach for stroke patients. However, there is still a lack of understanding of muscle functions when performing robot-assisted synchronous movements. The aim of this work is to explore the muscle activation patterns and the voluntary effort of participants during different robot-assisted bilateral training protocols. To this end, 10 healthy participants were recruited to take part in a 60-minute experiment. The experiment included two different bilateral exercises, and each exercise contained four different training protocols. Trajectories of the robots, interaction force and surface electromyogram signals were recorded during training. The results show that the robots do affect the muscle activation patterns during different training protocols and exercises rather than the controller. Specifically, the activity of muscles is reduced in robot-assisted training but is increased in active force involved robot-assisted training when compared to robot-unassisted training. Meanwhile, the voluntary effort of participants can be presented by the adjusted trajectories via the controller. In addition, the results also suggest that the activations for the same muscle groups in the left and right arms are highly correlated with each other in both exercises. Furthermore, the training protocols and methods developed in this work could be further extended in future clinical trials to investigate therapeutic outcomes for patients as well as to better understand bilateral recovery processes