Upper limb rehabilitation after stroke: ARAMIS a robomechatronic innovative approach and prototype.

Transcription

1 The Fourth IEEE RAS/EMBS International Conference on Biomedical Robotics and Biomechatronics Roma, Italy. June 24-27, 2012 Upper limb rehabilitation after stroke: ARAMIS a robomechatronic innovative approach and prototype. L. Pignolo (corresponding author), G. Dolce, G. Basta, L.F. Lucca, S. Serra, W.G. Sannita. Abstract ARAMIS (Automatic Recovery Arm Motility Integrated System) is a dual exoskeleton robot, intended to provide the therapist with novel and time/cost efficient approach to the rehabilitation of the paretic upper limb after stroke. The system has been developed in order to enable therapists to define and apply patient- specific rehabilitation exercises with multidisciplinary support by neurologist, engineers, ICT specialists and designers. ARAMIS allows three main strategies: 1) Asynchronous Exercise 2) Synchronous Exercise and 3) Virtual Exercise. This paper reports preliminary results from a patients sample trained by ARAMIS. I. INTRODUCTION is the third cause of death in Italy (10-12%) with estimated 186,000 new cases every year. About 30% of them survive with serious disabilities, and stroke is the most common cause of partial/complete motor disability of the upper/lower limb. All patients surviving the acute phase require continuous medical care over time and rehabilitation. The costs in hospitalization, logistics, assistance by medical/paramedical staff, and rehabilitation affect the national healthcare budget significantly; indirect costs, such as early retirement, further add to the burden for families and society [1]. In recent years, research has focused on the This work was supported by the Italian Ministery of Innovation, University and Research Innovative methodologies and tools in medical rehabilitation of the disabilities resulting from severe acquired brain lesions ; DM 593/00. L. Pignolo is with RAN-Research in Adavanced NeuroRehabilitation, "mailto:l.pignolo@istitutosantanna.it" }) G. Dolce is Scientific Director of S. Anna Institute for Neurorehabilitation and RAN-Research in Adavanced NeuroRehabilitation, "mailto:giulianodolce@libero.it" }). G Basta is S:Anna Institute for NeuroRehabiltation physiotherapist "mailto:g.basta@istitutosantanna.it" }) L.F. Lucca is chief of Semi Intensive Care Unit and Brain Injury Care Unit, S.Anna Institute for NeuroRehabilitation Crotone, ITALY ( { HYPERLINK "mailto:l.lucca@istitutosantanna.it" }). S. Serra., is chief of Motor functional and cognitive behavioral Rehabilitation Unit, S.Anna Institute for NeuroRehabilitation, Crotone, ITALY ( { HYPERLINK "mailto:s.serra@istitutosantanna.it" }). W.G. Sannita, Director of Department of Neuroscience, Ophthalmology and Genetic, University of Genova, Genova, Italy, and Department of Psychiatry, State University of New York, Stony Brook, NY, USA. ( { HYPERLINK "mailto:wgs@dism.unige.it.it" }). quantitative assessment of the upper and lower limbs residual motility in order to increase the effectiveness of rehabilitation, reduce in length the replacement cycle of patients in their social and working life, and control the healthcare direct costs. However, detailed pathophysiological knowledge of the mechanisms mediating in the brain functional re-arrangement and recuperation after brain damage still lacks and the rehabilitation procedures in use have been developed empirically. Further research is therefore mandatory to devise better procedures for the rehabilitation of the arm and shoulder specific motor organization and functional requirements [2,3]. Adequate tools are also needed to validate the available rehabilitation procedures over a wide range of adaptation conditions Virtual reality and mechatronic technologies offer a variety of applicative opportunities; robots and automated systems can be used to define protocols compensating for the therapists limitations in objectivity, replication, repeatability, interaction, feedback, etc. A growing number of scientific papers has reported about robot prototypes (from [4] to [10]) developed for rehabilitation purposes. This paper describes the rationale, design, architecture, and preliminary results in rehabilitation of prototype ARAMIS (Automatic Recovery Arm Motility Integrated System) [10], an integrated approach purported to implement the upper limb rehabilitation protocols by combining biomechanical (mechatronic component) and cognitive stimuli (virtual reality component). The ARAMIS rationale is based on evidence that [1][3] a paretic arm can recover its motor function in the first 3 4 months after hemispheric damage only if an alternative brain motor organization develops, is able to mimic the system original properties, and is trained compliant to its intrinsic potentialities. II. ARAMIS NEUROLOGICAL BACKGROUND The upper limb evolutionary role in controlling the hand movement in the subject s own space under the control of vision [4] requires functional independence; the motor system lateralizes early in extra-uterine life and the contralateral and ipsilateral control systems become progressively predominant and functionally silent, respectively. The spontaneous re-arrangement, however, is not necessary driven by functional or evolutionary rules and can lead to unfit patterns such as spasticity, hypotonia or synergies if not properly controlled. Intensity and specificity of exercise [13] and early, repetitive, function-efficient, meaningful and motivating training are mandatory. There is /12/$ IEEE 1410

2 evidence that recovery of the paretic arm needs to progress from proximal to distal under central control, benefits from the (partly bilateral) proximal innervation and is mediated by brain plasticity; shoulder and elbow play key roles in recovery [14]. Intense (e.g. 2 hrs/day), early (within 2 weeks from brain injury), and prolonged (over 3 months, with proper progression) training is thought to favor early spontaneous synaptic re-organization and new motor arrangements consistent with the brain physiological neuronal processes, neuronal wiring, interaction and control economy [15,16,17]. III. ARAMIS ARCHITECTURE A. Mechatronic Component ARAMIS system is a robotic platform featuring a couple of fully-motorized 6 DOF symmetric exoskeletons. The root joint of every exoskeleton acts as an interface between the robotic arm and its support in order to reduce load on the subject. The system robustness and the reduction of implementation costs are ensured by the ARAMIS structure with actuation element groups distributed along the serial kinematic chain; this choice is alternative to the use of actuation groups external to the kinematic chain, drive by a wire based transmission. The actuation group (Maxon motor AG, Sachseln, CH) consists of a DC Brushed Motor with moving coil rotor and high performance Neodymium magnets (RE-Program), coupled with Planetary Gearhead in order to increase torque capability of motor.a three channel high resolution Optical encoder provide the main angular position feedback of the controller position loop. An innovative integrated joint has been developed in order to enable the exoskeleton back driveability [10]. Kinematics and dynamic data at the joint are continuously acquired and stored by the control system, that evaluates the weight torque and the strength delivered by the patient to the exoskeleton, with strength compensation by control of each upper limb posture and support of movement by a suitable drive motor. 1. Aramis Manager, the main framework module for new patients registration, access to the patients database and relevant information needed to plan and carry on the rehabilitative protocol early hases. In addition, ARAMIS Manager provides quantitative feedback information and allows controlling the exoskeletons and the Virtual reality hardware consistent with the training protocol and modalities. 2. Exercise Builder, the module allowing implement virtual 3D scenarios for the patient to interact with when trained in Virtual reality settings. 3. HMD Interface is activated when required during Virtual reality training. The module implements an advanced 3D real time graphic application that collects postural data from the exoskeleton sensor array and from HMD sensor, in order to reproduce a natural interaction between patient and virtual environment. 4. The dedicated software Posis analyses the biomechanics data obtained by monitoring the training sessions through a 3D player and signal processing descriptors of the patient s motor performance. This tool of the ARAMIS framework is crucial when analysing the early effects of rehabilitation and upgrading the trainign protocols/modalities. The robot main duty is to compensate for the inadequate strength and accuracy of the paretic arm and limit the effect of gravity during training. Each exoskeleton can record (motion capture) the movements of the sample (healthy) arm for replication by the patient s paretic arm in synchronous or asynchronous modalities depending on the exercise typology or training program. The ARAMIS motion control is based on the following main elements: --Programmable Multi Axis Control Card; --Axis interface and IO stations; --Servo-amplifiers. The motion control PMAC board is hosted by a workstation (WS1) that is used for direct interface to therapist management software. The mechatronic platform is fully controlled by a software framework composed by the Aramis Framework (a fully integrated set of software that enables the therapist to plan and process the rehabilitation protocol) and four dedicated software modules distributed on two workstations (WS1; WS2) implemented in order to fulfill the entire set of functional requirements of the rehabilitation process : Fig. 1. Motion control architecture of ARAMIS rehabilitation platform ARAMIS allow rehabilitation exercises to be performed according to three main stategies: -asynchronous ways replicating on the affected limb exercises previously registered with the patient's healthy limb; in this way the movement mode can vary from completely passive to completely active, through varying 1411

3 degrees of intervention that the robot can exert on the patient s arm. - synchronous ways: the patient wears both exoskeletons and with its own limb healthy imposes synchronously exoskeleton worn by movement on affected limb, realizing self Rehabilitation sessions. - in virtual environments: the patient wears the exoskeleton and the Head Mounted Display to interact with virtual objects in that full immersive scenario, with visual and audio feedback [18]. Every exercises is modulated and acquired on the basis of the unique features of each patient. IV. ARAMIS: A PRELIMINARY STUDY ON APPLICABILITY Inpatients with hemiparesis in the subacute phase after stroke and hospitalized in the S. Anna Institute were recruited for a pilot, open study of applicability. Admission criteria were a disabling motor impairment after a first acute cerebrovascular event and age between 18 and 80 yrs. Exclusion criteria were (i) brain lesion of noncerebrovascular aetiology or brain damage in the posterior cerebral circulation; (ii) serious cognitive (Mini-Mental State Examination < 24), linguistic, or perceptual deficits; (iii) absence of trunk control while seated; (iv) lack of consent to participate in the study; (v) epilepsy. Treatment Each patient underwent a specific ARAMIS (Fig. 2) [10,11] treatment for the upper limb through the 6 actives DOF allowing to perform all movements in space. The treatment consisted of one 50-min session/day, 5 days a week, for a total period of at least 7 weeks. The protocol was designed to include a progression and mode of execution of the movement itself, from passive to assisted movement to spontaneous movement. Evaluations The subjects motor performance was assessed in baseline and at the end of treatment by conventional scales. The Fugl- Meyer scale for upper limbs (modified by Lindmark and Hamrin; upper scores: 115[total], 8 [pain], 63 [overall motor function]) [19,20], the FIM [21,22] and the Motricity Index for Upper Extremity were used. The Lindmark adaptation of the Fugl-Meyer Scale was chosen for this experimental study for its combining the functional limitation with the underlying impairment; it uses an evaluation scale comparable to the original one and has been validated trough comparison with the Fugl-Meyer score. A descriptive analysis of the changes after treatment was performed by comparison with the scales scores at baseline (Student s t- test). The study protocol was approved in September 2009 by the Italian Ministry of Health and Social Affairs Department for Innovation Directorate-General Pharmaceuticals and Medical Devices and by the local Ethical Committee and in accordance with the declaration of Helsinki. Fig 2: The ARAMIS prototype and rehabilitation setting Fourteen patients with upper limb disability due to hemispheric ischemic stroke participated in the study (11 men; age range: yrs.; mean 67±11.2 yrs.). Summary demographics and clinical condition are in Table I. Six had right-side and 8 left-side hemispheric lesions; the mean time from the acute event was 21±6.2 days. All subjects were treated by an ARAMIS protocol with 31±4.7 session over a 54±3.6 days period of time in parallel with a conventional ADL-compatible training for e.g. eating, drinking, etc. The Fugl-Meyer total score improved from 48±18 at baseline to 75±27 at the end of the ARAMIS rehabilitation protocol (p<0.003), with a mean improvement of 56%. The score for pain improved from 4.5±2 to 7±1.2 (p <0.0004) and the overall motor function improved from 11.7±10 to 27.5±17.4 (p < 0.004). The FIM total score improved from 65±21 at baseline to 94±14 at the end of treatment ( p < 0.001). A significant improvement was observed also at the Motricity Index for Upper Extremity (p >0.005). All therapists reported appreciating the ARAMIS approach both for its advantages in logistics and organization in the clinicalrehabilitative procedures and for the responses obtained. Table I. Patients summary demographics and clinical conditions Fugl-Meyer total score avg Subje ct Age (yrs) D H F1 62 R M2 65 R M3 74 L M4 78 R F5 68 R M6 65 R M7 79 R M8 78 R M9 49 R M10 54 R M11 69 R M12 54 R F13 43 R M14 69 R Pathology Side of stroke baselin e after treatment improvement (%) Right Left Right Left Left Left Left Left Right Right Right Left Left Right FM: Fugl-Meyer; DH: dominant hand; L: left; R:Right 1412

4 V. COMMENT The pilot study documents the patients capability of undergoing a full-length rehabilitation treatment by ARAMIS, with good tolerance and satisfaction. The observed improvement after treatment was comparable to the reports in the scientific literature concerning the standard and robot-assisted rehabilitation procedures [23]. Albeit preliminary, these results support the suggested potentialities of robot-mediated rehabilitation treatments [24] of these patients and the hypothesis that improvement in motor abilities after brain injury follows the proximal-todistal progression, with a variety of finalized and functionally relevant motor actions requiring adequate control. ACKNOWLEDGMENT The ARAMIS prototype has been designed and engineered in partnership by the Institute S. Anna RAN, Crotone, and CETMA Consortium (Design and Materials Technology Centre), Brindisi. The prototype has been built by Telcom SpA, a partner company of CETMA Consortium. REFERENCES [1] ( Review ) Truelsen T, Bonita R in developing Countries: a continuing challenge. 2003;7(3): [2] (Topics in Rehabilitation) Bayona NA, Bitensky J, Salter K,, Teasell R: Plasticity and reorganization of the uninjured brain. (2005, 12(3):1-10). [3] (Physical Medicine & Rehabilitation Clinics of North America) Nudo RJ. Functional and structural plasticity in motor cortex: implications for stroke recovery , 14: [4] (J Rehab Res Dev) Prange GB et Al. Systematic review of the effect of robot-aided therapy on recovery of the hemiparetic arm after stroke. 2006, 43:171. [5] (Current Neurol Neuroscie Reports) Volpe BT et Al. Robotics and other devices in the treatment of patient recovering from stroke. 2002, 5(6) [6] (Top Rehab) Lum P et Al Robotic Devices for movement therapy after stroke: : Current and challenges to clinical acceptance. 2002, 8: [7] (Arch Physical Med Rehab) Fasoli SE et Al. Effects of robotic therapy on motor impairment and recovery in chronic stroke. 2003,84(4): [8] (Autonomous Robots) Loureiro R et Al. Upper limb robot mediated stroke therapy - GENTLE/s approach. 2003, 15(1): [9] (Top Rehabil) Hidler J et Al. Advances in the understanding and treatment of stroke impairment using robotic devices. 2005, 12: [10] (Journal of Rehabilitation Medicine) Colizzi L, Lidonnici A, Pignolo L: The ARAMIS project: A concept robot and technical design , 41: [11] (Journal of Rehabilitation Medicine) Dolce G, Lucca LF, Pignolo L: Robot-assisted rehabilitation of the paretic upper limb: Rationale of the ARAMIS project , 41: [12] (Annual Reviews of Neuroscience) Rizzolatti G, Craighero L. The mirror neuron system. 2004;27: [13] (Lancet) Kwakkel G, Wagenaar RC, Twisk JW, Lankhorst GJ, Koetsier JC. Intensity of leg and arm training after primary middlecerebral-artery stroke: a randomized trial. 1999;354: [14] (Exp Brain Res.) Michaelsen SM, Jacobs S, Roby-Brami A, Levin MF. Compensation for distal impairments of grasping in adults with hemiparesis. 2004; 157: [15] (Progress in Neurobiology) Schaechter JD. Motor rehabilitation and brain plasticity after hemiparetic stroke. 2004;73: [16] (.) Liepert J, Bauder H,Wolfgang H.. Miltner R, Taub E, Weiller C.Treatment-Induced Cortical Reorganization After in Humans. 2000;31:1210. [17] (Curr Opin Neurol) Krakauer J. Motor learning: its relevance to stroke recovery and neurorehabilitation. 2006; 19: [18] (Progress in Neurobiology) Will B, Galani R, Kelche C, Rosenzweig MR: Recovery from brain injury in animals: relative efficacy of environmental enrichment, physical exercise or formal training ( ). 2004, 72(3) [19] (Scand J Rehabil Med ) Fugl-Meyer AR, Jääskö L, Leyman I, Olsson S, Steglind S. The post-stroke hemiplegic patient. 1. A method for evaluation of physical performance. 1975; 7: [20] (Scand J Rehabil Med) Lindmark B, Hamrin E. Evaluation of functional capacity after stroke as a basis for active intervention. Validation of a modified chart for motor capacity assessment. 1988; 20: [21] (Am J Phys Med Rehabil) Tesio L, Granger CV, Perucca L, Franchignoni FP, Battaglia MA, Russel CF. The FIM instrument in the United States and Italy: a comparative study. 2002; 81: [22] (Ricerca Riabil) Functional Indipendent Measure: versione italiana. Manuale d uso [Functional Independent Measure: Italian version. Users manual]. 1992; Suppl 2: 1 44 (in Italian). [23] (Journal of Neuroengin and Rehab) Crespo LM, Reinkensmeyer DJ: Review of control strategies for robotic movement training after neurologic injury. 2009; 6:20. [24] (Journal of Rehabilitation Medicine) Pignolo L: Robotics in neurorehabilitation , 41:

5 Nome file: Pignolo et Al_Aramis_402.doc Directory: H:\BIOROB definitivo Modello: D:\Personal\Papercept\support\its\files\ieeeconf_letter.dot Titolo: Oggetto: IEEE Transactions on Magnetics Autore: pradeep misra Parole chiave: Commenti: Data creazione: 03/05/ Numero revisione: 3 Data ultimo salvataggio: 03/05/ Autore ultimo salvataggio: l.pignolo Tempo totale modifica 150 minuti Data ultima stampa: 03/05/ Come da ultima stampa completa Numero pagine: 4 Numero parole: (circa) Numero caratteri: (circa) 1414