Objective.Several training programs have been developed in the past to restore motor functions after stroke. Their efficacy strongly relies on the possibility to assess individual levels of impairment and recovery rate. However, commonly used clinical scales rely mainly on subjective functional assessments and are not able to provide a complete description of patients’ neuro-biomechanical status. Therefore, current clinical tests should be integrated with specific physiological measurements, i.e. kinematic, muscular, and brain activities, to obtain a deep understanding of patients’ condition and of its evolution through time and rehabilitative intervention.Approach.We proposed a multivariate approach for motor control assessment that simultaneously measures kinematic, muscle and brain activity and combines the main physiological variables extracted from these signals using principal component analysis (PCA). We tested it in a group of six sub-acute stroke subjects evaluated extensively before and after a four-week training, using an upper-limb exoskeleton while performing a reaching task, along with brain and muscle measurements.Main results.After training, all subjects exhibited clinical improvements correlating with changes in kinematics, muscle synergies, and spinal maps. Movements were smoother and faster, while muscle synergies increased in numbers and became more similar to those of the healthy controls. These findings were coupled with changes in cortical oscillations depicted by EEG-topographies. When combining these physiological variables using PCA, we found that (i) patients’ kinematic and spinal maps parameters improved continuously during the four assessments; (ii) muscle coordination augmented mainly during treatment, and (iii) brain oscillations recovered mostly pre-treatment as a consequence of short-term subacute changes.Significance.Although these are preliminary results, the proposed approach has the potential of identifying significant biomarkers for patient stratification as well as for the design of more effective rehabilitation protocols.

The loss of a hand disrupts the sophisticated neural pathways between the brain and the hand, severely affecting the level of independence of the patient and the ability to carry out daily work and social activities. Recent years have witnessed a rapid evolution of surgical techniques and technologies aimed at restoring dexterous motor functions akin to those of the human hand through bionic solutions, mainly relying on probing of electrical signals from the residual nerves and muscles. Here, we report the clinical implementation of an interface aimed at achieving this goal by exploiting muscle deformation, sensed through passive magnetic implants: the myokinetic interface. One participant with a transradial amputation received an implantation of six permanent magnets in three muscles of the residual limb. A truly self-contained myokinetic prosthetic arm embedding all hardware components and the battery within the prosthetic socket was developed. By retrieving muscle deformation caused by voluntary contraction through magnet localization, we were able to control in real time a dexterous robotic hand following both a direct control strategy and a pattern recognition approach. In just 6 weeks, the participant successfully completed a series of functional tests, achieving scores similar to those achieved when using myoelectric controllers, a standard-of-care solution, with comparable physical and mental workloads. This experience raised conceptual and technical limits of the interface, which nevertheless pave the way for further investigations in a partially unexplored field. This study also demonstrates a viable possibility for intuitively interfacing humans with robotic technologies.

Aerobic exercise (AE) and non-aerobic neuromuscular electric stimulation (NMES) are common interventions used in physical therapy. We explored the dose-dependency (low, medium, high) of these interventions on biochemical factors, such as brain derived neurotrophic growth factor (BDNF), vascular endothelial growth factor-A (VEGF-A), insulin-like growth factor-1 (IGF-1) and Klotho, in the blood and brain of normal rats, as well as a treadmill-based maximum capacity test (MCT). A medium dose of AE produced the most improvement in MCT with dose-dependent changes in Klotho in the blood. A dose-dependent increase of BDNF was evident following completion of an NMES protocol, but there was no improvement in MCT performance. Gene expression in the hippocampus was increased after both AE and NMES, with IGF-1 being a signaling molecule that correlated with MCT performance in the AE conditions, but also highly correlated with VEGF-A and Klotho. Blood Klotho levels can serve as a biomarker of therapeutic dosing of AE, whereas IGF-1 is a key molecule coupled to gene expression of other molecules in the hippocampus. This approach provides a translatable paradigm to investigate the mode and mechanism of action of interventions employed in physical therapy that can improve our understanding of how these factors change under pathological conditions.

Psycho-social impact of social distancing and isolation due to the COVID-19 containment measures on patients with physical disabilities - European Journal of Physical and Rehabilitation Medicine 2021 February;57(1):158-65 - Minerva Medica - Journals

It is widely known that nervous and muscular systems work together and that they are strictly dependent in their structure and functions. Consequently, muscles undergo macro and microscopic changes with subsequent alterations after a central nervous system (CNS) disease. Despite this, only a few researchers have addressed the problem of skeletal muscle abnormalities following CNS diseases. The purpose of this review is to summarize the current knowledge on the potential mechanisms responsible for changes in skeletal muscle of patients suffering from some of the most common CSN disorders (Stroke, Multiple Sclerosis, Parkinson’s disease). With this purpose, we analyzed the studies published in the last decade. The published studies show an extreme heterogeneity of the assessment modality and examined population. Furthermore, it is evident that thanks to different evaluation methodologies, it is now possible to implement knowledge on muscle morphology, for a long time limited by the requirement of muscle biopsies. This could be the first step to amplify studies aimed to analyze muscle characteristics in CNS disease and developing rehabilitation protocols to prevent and treat the muscle, often neglected in CNS disease.

Cancer cachexia has been reported to be directly responsible for at least 20% of cancer deaths. Management of muscle wasting in cancer-associated cachexia appears to be of pivotal importance for survival of patients. In this regard, it would be interesting to identify before its patent appearance eventual functional markers of muscle damage, to plan specific exercise protocols to counteract cachexia. The muscle function of 13 oncologic patients and 15 controls was analyzed through: i) analysis of the oxidative metabolism, indirectly evaluated trough dosage of blood lactate levels before and after a submaximal incremental exercise on a treadmill; ii) analysis of strength and, iii) endurance, in both lower and upper limbs muscles, employing an isokinetic dynamometer. Statistical analyses were carried out to compare the muscle activities between groups. Analysis of oxidative metabolism during the incremental exercise on a treadmill showed that patients performed a shorter exercise than controls. Lactate levels were significantly higher in patients both at baseline and after the task. Muscle strength analysis in patients group showed a reduction of Maximum Voluntary Contraction during the isometric contraction and, a tendency to fatigue during endurance task. Data emerging from this study highlight an impairment of muscle oxidative metabolism in subjects affected by a pre-cachexia stage of cancer. A trend of precocious fatigability and an impairment of muscle strength production were also observed. This evidence underlines the relevance of assessing muscle function in order to develop novel rehabilitative approaches able to counteract motor impairment and eventually to prevent cachexia in these patients.