Robot-Aided Neurorehabilitation: From Evidence-Based to Science-Based Rehabilitation

Abstract

There is no "magic bullet" in rehabilitation. In the absence of direct neural transplants, neurological rehabilitation is an arduous process. We have pioneered the clinical application of robotics in stroke rehabilitation and have shown evidence of the positive impact of targeted exercise on stroke recovery. In this article, we will review results obtained in the initial clinical trials with 96 stroke patients at the Burke Rehabilitation Hospital. We will provide evidence that robot-aided training enhances recovery, that this enhanced recovery is sustained in the long term, and that this recovery is not due to a general physiological improvement--in fact, it appears to be limb and muscle group specific. An evidence-based approach must now segue into a more scientific approach to stroke rehabilitation. Given the length of the required protocols and patients' variability and limited census, the practical limitations of the evidence-based approach are self-evident and extend trials for years. Each patient and lesion is unique in stroke rehabilitation, so there is no reason to believe that a "one-size-fits-all" optimal treatment exists. To optimize therapy for individual patients, we need science-based models. In this article, we will summarize the scientific tools and models that we are investigating and present some of the results to date.

Arm weight support training improves functional motor outcome and movement smoothness after stroke

“…Considering that the second motor task did not make provision for an auditory cue for the catching/ returning movements, the patients could not be driven to execute faster movements than they would normally have executed, and therefore, velocity indices could not be used to reveal functional motor outcome improvements. Previous studies concerning robotic rehabilitation approaches in stroke patients have reported improved proximal arm functions (Burgar et al, 2000;Krebs et al 2002), but did not show an optimal motor recovery of the distal motor segments of the upper limb, which are involved in most ADL (Wisneski and Johnson, 2007). Conversely, arm weight support rehabilitation leads to reduced NJ and to increased hand RoM, which is crucially important for positive recovery of upper limb motor control (Morasso, 1981;Wisneski and Johnson, 2007), and possibly related to improved functional ability in executing ADL.…”

“…This study examined the effectiveness of rehabilitation training performed with or without an arm weight sup- Although previous studies conducted in chronic stroke patients have reported an increased functional motor gain after arm-weight support device training (Krebs et al, 2002;Macclellan et al, 2005;Sanchez et al, 2006;Masiero et al, 2007;Colombo et al, 2008;Kwakkel et al, 2008), the present study was the first to be conducted during the acute phase after stroke, using kinematic analysis to evaluate upper limb motor performance. It is strongly suggested in the literature that the acute phases following neurological damage are the most sensitive to approaches designed to exploit neural plasticity (Paolucci et al, 2000;Dobkin, 2004), particularly the first six months after stroke (Paolucci et al, 2000).…”

“…These devices allow time-specific tasks to be executed repeatedly in a controlled and reliable way, as this has been shown to be a determining factor in facilitating cortical reorganization, allowing a concomitant increase in motor ability and improved functional activity performance (Liepert, 2006). Recent evidence has shown that intensive repetition of movements could make a useful contribution to clinical practice (Kawahira et al, 2010), constituting a promising approach for patients affected by motor impairments due to neurological diseases, such as multiple sclerosis (Gijbels et al, 2011), cervical spinal cord injuries (Zariffa et al, 2012), and chronic stroke (Krebs et al, 2002;Macclellan et al, 2005;Sanchez et al, 2006;Masiero et al, 2007;Colombo et al, 2008;Kwakkel et al, 2008). Indeed, the use of devices designed to intensify therapy in the single patient could be a promising field of investigation (Masiero et al, 2009).…”

“…From this perspective, it is well known that the acute phases after neurological injury are the most sensitive to approaches designed to exploit neural plasticity (Paolucci et al, 2000;Dobkin, 2004). Even though previous studies, exploring the servoactuated robotic rehabilitation approach, confirmed an improvement of proximal arm functions (Krebs et al, 2002), optimal extension of this motor recovery to the distal motor segments of the upper limb remains to be demonstrated (Wisneski and Johnson, 2007). Conversely, arm weight support rehabilitation based on the use of passive orthotic devices has been shown to improve features of hand movements that may be considered crucially important for achieving a positive recovery of upper limb motor control (Morasso, 1981;Wisneski and Johnson, 2007) and may be related to enhanced functional ability.…”

Development of the augmented musculature device.

“…(Krebs et al, 1998) These measures are currently being used as powerful tools in a quantitative, science-based approach to the study of recovery from neurological injury. (Krebs et al, 2002) These benefits make it desirable to distribute stroke robots and make them as widely available as possible. Not only would this provide better therapy and more complete recovery to a larger population, but it would also allow for the collection of recovery data on a larger group of subjects and increase the rehabilitation community's understanding of the progression of therapy, which in turn would allow for therapy better matched to the patient, which would lead to more complete recovery, etc.…”