MARS Development Project D3:
Targeting T-WREX to Improve Functional Outcomes of Upper Extremity Therapy
Executive Summary of Aims:
The goal of this project is to develop therapeutic technology that individuals with a moderate/severe stroke can use to improve the functional use of their upper extremity (UE) without the continuous presence of a rehabilitation therapist. In the previous grant period we developed a device called Therapy WREX (T-WREX) and demonstrated that it can improve UE movement ability following chronic stroke. The device uses a passive, gravity-balancing orthosis (based on WREX –Wilmington Robotic Exoskeleton, developed by Rahman et al. with previous NIDRR support), a hand grip sensor, and virtual reality exercises to allow people with severe weakness to practice simulated functional activities. This work is being commercialized as the Armeo therapy system by Hocoma, A.G, in Zurich.
The T-WREX/Armeo training approach has the potential to impact clinical practice of stroke rehabilitation because it can significantly improves motor ability (Fig. 2a). Further, it is potentially less expensive and safer than robotic therapy approaches, even though it has similar effectiveness (Fig. 2a). Patients find it more motivating than conventional self-supervised therapy exercises (Fig. 2c). In addition, it can be utilized for extended periods of time (e.g. 1 hour) without direct therapist presence, requiring less than 5 minutes of set-up time by the therapist (as measured with a stopwatch in our study).
This project asks, “How can we improve on these initial, positive results of T-WREX therapy?” The functional gains following training with T-WREX are significant but small (, which is consistent with previous studies of robotic therapy devices for the upper extremity, which found modest functional benefits of robotic therapy on ADLs. The goal of this project is therefore to improve the functional outcomes of machine-based therapy, using T-WREX as the test platform.
We will develop three new features for the system that improve the carryover of motor gains to functional arm and hand use during ADLs: better integration of hand and wrist training with arm training; the development of low-cost computer vision technology that enables continued practice with T-WREX software at home, and the incorporation of non-simulated task practice as a key component of the therapy. Accordingly, the specific aims of this project are to:
- Develop technology that allows T-WREX users to incorporate movement practice with the forearm, wrist and hand, thereby allowing users to progress treatment to key distal movements that promote functional transfer (Project years 1-2).
- Develop computer vision technology that allows T-WREX users to continue computer-motivated, arm-supported, functional movement training at home for longer durations (Project years 1-2).
- Develop instructional video clips that teach stroke survivors how to transfer movement gains to activities of daily living (ADL’s) (Project year 1).
To evaluate this technology, we will conduct a randomized, controlled therapeutic test of its effectiveness in improving functional outcomes (Years 3-5). We hypothesize that training with the enhanced T-WREX, Gesture Therapy and multi-media functional exercises will be more effective in improving functional outcomes than training without them.
Watch the 2009 Advisory Board Meeting T-WREX presentation