Functional Restoration for the Stroke Survivor: Informing the Efforts of Engineers

Abstract

As bioengineers begin to notice the importance of therapy in the recovery from stroke and other brain injuries, new technologies will be increasingly conceived, adapted, and designed to improve the patient's road to recovery. What is clear from engineering history, however, is that the best engineering efforts are often built on strong scientific foundations. In an effort to inform engineers with the necessary background on cutting edge research in the field of stroke and motor recovery, this article summarizes the views of several experts in the field as a result of a workshop held in 2006 on the topic. Here we elaborate on several areas relevant to this goal, including the pathophysiology of stroke and stroke recovery, the biomechanics, the secondary peripheral changes in muscle and other tissue, and the results of neuroimaging studies. One conclusion is that the current state of knowledge is now ripe for research using machines but that highly sophisticated robotic devices may not yet be needed. Instead, what may be needed is basic evidence that shows a difference in one therapeutic strategy over another. KeywordsCVA; control; movement; muscle; rehabilitation human; stroke There has been considerable attention in recent years to the natural course of recovery from stroke and to the effects of therapeutic intervention. This should not come as a great surprise, because stroke is by far the leading cause of physical disability among adults in the United States, with annual rehabilitation costs in the billions. The prevalence of stroke is enormous. According to the American Heart Association, the number of stroke survivors increased from 1.5 million in the early 1970s to 2.4 million by the early 1990s, 1 to over 3 million today. This increase goes hand in hand with the aging of our population. Currently, the population of those 65 years or older is approximately 33+ million (12.7% of US population in 1999) and is projected to be 53 million by 2020 and 77 million by 2040 (see www.strokeassociation.org). The percentage of Americans 45-54 years old living with stroke is under 2%; it is almost 4% in those 55-64 years old, rises to 6% for those 65-74, and rises to more than 10% for those 75 and over. 2 Clearly, the issues related to the long-term treatment of stroke will be increasingly important societal issues.Furthermore, although the incidence of stroke is falling overall, presumably because of the improvement in medical management of hypertension, hyperlipidemia, and vascular disease, NIH Public Access

Use of Hand Rehabilitation Board (Dominic’s Board) in Post Traumatic/Stroke Rehabilitation of the Upper Limbs

“…Although several devices have been used attempting to achieve similar purpose, only few of them have actually reached the targeted population [5]. Also, the outcome of those already in use is not as positive as expected Maciejasz who cited Patton et al [7], due to several associated shortfalls from their uses.…”

Development of novel devices for upper-extremity rehabilitation

“…However, when the assist-as-needed strategy is implemented incorrectly, patients can actually reduce their own efforts and let the robot take over [231]. Thus, when providing assistance, a difference should be made between completing a movement and enabling the completion [152]. The first takes over when the performance targets aren't met by the patient, but the second does not.…”

“…It should also be minimized to stop the patient from reducing his effort and relying on the adaptive support of the robot [231], as they tend to do. In this light, an distinction should be made between assistance which enable movement, like gravity support, and which enhances it, for instance by completing movements [152]. With the first, the patient still has to complete the movement, but the second directly interferes with the task objectives of the patients, allowing the robot to take over.…”

“…With such passive actuators, limb movements may still be facilitated by adding scalable weight support to the device [45,44,206,163,164,92,47]. Weight support only facilitates movements, but does not complete them, keeping the patients actively involved [231,152].…”

“…When giving assistance, it may be best to only enable voluntary movements, not to complete them [231,152].…”