Principal Investigator: Carolynn Patten, PhD, PT Investigators: C. Maria Kim, MSc, PT; Jody M. Dozono, MPT; Abigail M. Andrade, BS PTA; Christine A. Dairaghi, BS; and Peter S. Lum, PhD Project Category: Stroke - 2005 Objective: The long-term goal of this research is to develop efficient and effective therapeutic interventions for rehabilitation of persons with post-stroke hemiparesis. Key to attainment of this goal is demonstration of the physiologic mechanisms mediating adaptation to therapeutic intervention and understanding their effects on functional motor performance. We know of no studies systematically examining simultaneous training-related effects and adaptations in physiologic mechanisms mediating these effects. Therefore, results of this study will provide sound, scientific evidence of physiologic mechanisms responsible for weakness, evidence of the processes involved in neuromuscular adaptation, and will elucidate the relationship between impairment and motor disability in post-stroke hemiparesis. This information will form a basis for prescription of appropriate, focused, timely, and effective clinical interventions. Research Plan and Methods: This proposal extends the work accomplished in our initial study (project #B2405R, 'Effects of Strength Training on Upper-limb Function in Post-stroke Hemiparesis'). Here we propose a double-blind, randomized clinical trial of staged rehabilitation for the upper-extremity involving sequential delivery of functional therapy and high intensity resistance training. Therefore, this proposal directly compares the effects of functional and resistance training delivered individually. Our previous work investigated a hybrid therapy of functional and resistance training against functional training alone. All subjects will participate in a 6-week run-in period of no treatment. This no-treatment block will afford multiple baseline measurements and, in addition, will provide information regarding the rate and magnitude of any spontaneous recovery without treatment. Following the second baseline measurement, all subjects will be randomized to receive either 6 weeks of functional training followed by 6 weeks of high-intensity resistance training or resistance training followed by functional training. Re-evaluation will occur following each block of treatment, and retention effects will be evaluated after 6 and 12 months with no additional treatment. Subjects will be evaluated with: outcome measures used broadly in Clinical Neurology and Rehabilitation, a battery of biomechanical performance measures including strength, muscle activation, reflex modulation and motor coordination, and with kinematics of free reaching movements. We will investigate persons in the intermediate phase of recovery, which we define as between 6 and 18 months post-CVA, having completed all inpatient and outpatient therapies, with continued experience of residual motor deficits. Clinical Relevance to the VA: Stroke is a preeminent cause of physical disability in the American population and particularly the veteran population. In excess of 700,000 people in the United States suffer strokes each year, accounting for one half of all patients hospitalized for acute neurological conditions. Due to improvements in the acute clinical management of stroke, the majority of these persons now survive but almost 40% have significant physical disabilities. There is growing evidence that weakness is the predominant impairment following stroke, and recent research has called for more work addressing the role of muscular strength in rehabilitation of persons with post-stroke hemiplegia. Our preliminary data, obtained in the previous grant period, strongly suggest that inclusion of high-intensity resistance training in upper-extremity rehabilitation promotes superior outcomes at all levels of the ICIDH-2 axis: impairment, activities and participation. Moreover, the effects of a hybrid therapy involving both resistance and functional training provide strong indication that high-intensity activities do not present deleterious consequences (i.e., exacerbation of hypertonia, injury/pain, interference with recovery of motor function) in hemiparetic persons. The proposed project focuses on developing an improved understanding of the specific delivery of resistance training in hemiparetic persons including means for optimizing the functional benefits of treatment. Progress Report and Findings to Date: This project was approved and funding was initiated in August 2005. As of this date, evaluation and treatment protocols have been developed. Six subjects have been enrolled for this multiple baseline, twenty-week intervention study. An additional eight subjects have been identified for baseline evaluation and enrollment beginning in May 2006. Research Plan for the Next Year: Project goals for this year involve continuation of the treatment intervention and development of analysis protocols for biomechanical and physiological data. Funding Source: VA RR&D Merit Review Funding Status: Active
|
