Marco Caimmi

Normative Data for an Instrumental Assessment of the Upper-Limb Functionality

Upper-limb movement analysis is important to monitor objectively rehabilitation interventions, contributing to improving the overall treatments outcomes. Simple, fast, easy-to-use, and applicable methods are required to allow routinely functional evaluation of patients with different pathologies and clinical conditions. This paper describes the Reaching and Hand-to-Mouth Evaluation Method, a fast procedure to assess the upper-limb motor control and functional ability, providing a set of normative data from 42 healthy subjects of different ages, evaluated for both the dominant and the nondominant limb motor performance. Sixteen of them were reevaluated after two weeks to perform test-retest reliability analysis. Data were clustered into three subgroups of different ages to test the method sensitivity to motor control differences. Experimental data show notable test-retest reliability in all tasks. Data from older and younger subjects show significant differences in the measures related to the ability for coordination thus showing the high sensitivity of the method to motor control differences. The presented method, provided with control data from healthy subjects, appears to be a suitable and reliable tool for the upper-limb functional assessment in the clinical environment.

A spherical parallel three degrees-of-freedom robot for ankle-foot neuro-rehabilitation

The ankle represents a fairly complex bone structure, resulting in kinematics that hinders a flawless robot-assisted recovery of foot motility in impaired subjects. The paper proposes a novel device for ankle-foot neuro-rehabilitation based on a mechatronic redesign of the remarkable Agile Eye spherical robot on the basis of clinical requisites. The kinematic design allows the positioning of the ankle articular center close to the machine rotation center with valuable benefits in term of therapy functions. The prototype, named PKAnkle, Parallel Kinematic machine for Ankle rehabilitation, provides a 6-axes load cell for the measure of subject interaction forces/torques, and it integrates a commercial EMG-acquisition system. Robot control provides active and passive therapeutic exercises.

Using Kinect for upper-limb functional evaluation in home rehabilitation: A comparison with a 3D stereoscopic passive marker system

The functional evaluation of the upper-limb can be clinically assessed through the analysis of the kinematics, the dynamics, and measures of motor control. Such measures are usually obtained in a clinical environment with commercial stereoscopic 3D devices that allow to sample kinematics at high frequency and with high accuracy and precision, but that are, on the other hand, expensive, time consuming, and, most of all, are not portable. Consequently, such assessments are available only in clinics. With the aim of developing applications for neurological patients movement analysis in home environment, an experimental study has been conducted to compare the performances of a passive-marker motion capture system with the Kinect. Data were acquired simultaneously with the two systems during reaching against gravity movements. Results suggest that Kinect may be a valid tool for studying reaching against gravity and assessing upper-limb functionality at home in neurological patients.

Kinect One-based biomechanical assessment of upper-limb performance compared to clinical scales in post-stroke patients.

This paper presents a Kinect One sensor-based protocol for the evaluation of the motor-performances of the upper limb of neurological patients during rehabilitative sessions. The assessment provides evaluations of kinematic, dynamic, motor and postural control variables. A pilot study was conducted on three post-stroke neurological patients, comparing Kinect-One biomechanical assessment with the outcomes of some of the most common clinical scales for the evaluation of the upper-limb functionality. Preliminary results indicate coherency between the clinical and instrumental evaluation. Moreover, the Kinect-One assessment seems to provide some complementary quantitative information, consistently integrating the clinical assessment.

Static and dynamic characterization of the LIGHTarm exoskeleton for rehabilitation

This paper presents LIGHTarm, a passive gravity compensated exoskeleton for upper-limb rehabilitation suitable for the use both in the clinical environment and at home. Despite the low-cost and not actuated design, LIGHTarm aims at providing remarkable back-drivability in wide portions of the upper-limb workspace. The weight-support and back-drivability features are experimentally investigated on three healthy subjects through the analysis of the EMG activity recorded in static conditions and during functional movements. Kinematics is also monitored. Preliminary results suggest that LIGHTarm sharply reduces muscular effort required for limb support, quite uniformly in the workspace, and that remarkable back-drivability is achieved during the execution of functional movements.

An affordable, adaptable, and hybrid assistive device for upper-limb neurorehabilitation

The paper presents a multisensory and multimodal device for neuromuscular rehabilitation of the upper limb, designed to enable enriched rehabilitation treatment in both clinical and home environments. Originating from an existing low-cost, variable-stiffness rehabilitation device, it expands its functionalities by integrating additional modules in order to augment application scenarios and applicable clinical techniques. The newly developed system focuses on the integration of a wearable neuromuscular electrical stimulation system, a virtual rehabilitation scenario, a low-cost unobtrusive sensory system and a patient model for adapting training task parameters. It also monitors the user behavior during each single session and its evolution throughout the entire training period. The result is a modular, integrated and affordable rehabilitation device, enabling a biomechanical, neurological, and physiological-based training of patients, including innovative features currently unavailable within off-the-shelf rehabilitation devices.

Passive and active gravity-compensation of LIGHTarm, an exoskeleton for the upper-limb rehabilitation

This paper presents LIGHTarm, an exoskeleton for the upper-limb neuro-rehabilitation, characterized by a peculiar kinematic structure, expressly conceived to face shoulder rhythm and elbow singularity issues. The device is developed in two versions. The first prototype of this rehabilitation device is unactuated, achieving gravity compensation through a passively mechanically compensated mechanism obtaining a cost-effective and intrinsically safe solution for semi-autonomous training at home. A limitation of passively gravity-compensated devices is that they lack a dynamically and on-line tunable weight-support. Actuated devices, in respect to non-actuated ones, allow “a step further” in the real-time control of tuning the gravity-compensation feature. Starting from its unactuated version, the actuated version is presented, together with the kinematics and dynamics analyses of the mechanism.

DUALarm: An open-source and 3D-printable device for upper limb neurorehabilitation

Positively advocating that low-cost additive 3D-printing technologies and open-source licensed software/hardware platforms represent an optimal solution to realize low-cost equipment, a mechanical and 3D-printable device for bilateral upper-limb rehabilitation is presented. The design and manufacturing process of this wheel-geared mechanism, enabling in-phase and anti-phase movements, will be openly provided online with the aim of making a set of customizable devices for neurorehabilitation exploitable all over the world even by people/countries with limited economical and technological resources. In order to characterize the interaction with the device, preliminary trials with EMG and kinematics recordings were performed on healthy subjects.

Quantitative EEG for Predicting Upper Limb Motor Recovery in Chronic Stroke Robot-Assisted Rehabilitation

Stroke is a leading cause for adult disability, which in many cases causes motor deficits. Despite the developments in motor rehabilitation techniques, recovery of upper limb functions after stroke is limited and heterogeneous in terms of outcomes, and knowledge of important factors that may affect the outcome of the therapy is necessary to make a reasonable prediction for individual patients. In this paper, we assessed the relationship between quantitative electroencephalographic (QEEG) measures and the motor outcome in chronic stroke patients that underwent a robot-assisted rehabilitation program to evaluate the utility of QEEG indices to predict motor recovery. For this purpose, we acquired resting-state electroencephalographic signals from which the power ratio index (PRI), delta/alpha ratio, and brain symmetry index were calculated. The outcome of the motor rehabilitation was evaluated using upper limb section of the Fugl–Meyer Assessment. We found that PRI was significantly correlated with the motor recovery, suggesting that this index may provide useful information to predict the rehabilitation outcome.

Ergonomics and kinematic compatibility of PKankle, a fully-parallel spherical robot for ankle-foot rehabilitation

PKankle is a robotic device based on a fully-parallel kinematic architecture and specifically designed for the neuro-rehabilitation of the ankle-foot complex. The peculiar kinematics allows the foot support to rotate, with good approximation, about the instantaneous center of rotation of the foot. An adjusting mechanical system allows the device to be employed in different patient positionings. Moreover, it features an integrated load cell for measuring subject interaction forces/torques, both to close impedance-based control loops and to obtain valuable clinical data, and a synchronized electromyographic acquisition system to analyze patients muscular activity. The present work describes kinematic and control aspects specifically addressed to enhance its ergonomics and physiological compatibility to the actual mobility of the ankle-foot complex. Preliminary experimental activities, performed by healthy subjects, have been carried out to assess the effectiveness of the adopted solutions.