Jan Kowalczewski

In-Home Tele-Rehabilitation Improves Tetraplegic Hand Function

Background. Spinal cord injury (SCI) survivors with tetraplegia have great difficulty performing activities of daily living (ADLs). Functional electrical stimulation (FES) combined with exercise therapy (ET) can improve hand function, but delivering the treatment is problematic. Objective. To compare 2 ET treatments delivered by in-home tele-therapy (IHT). Methods. Each treatment involved ET, tele-supervised 1 h/d, 5 d/wk for 6 weeks. Treatment 1: “conventional ET” comprised strength training, computer games played with a trackball, and therapeutic electrical stimulation (TES). Treatment 2: “ReJoyce ET” comprised FES-ET on a workstation, the Rehabilitation Joystick for Computerized Exercise (ReJoyce) with which participants played computer games associated with ADLs. Participants were block-randomized into group 1 receiving conventional ET first, followed by 1-month washout, and then ReJoyce ET and group 2 in reverse order. In all, 13 participants took part, 5 completing the study with both hands, such that both groups had a sample size of 9. Primary outcome measure: Action Research Arm Test (ARAT). Secondary outcome measures: grasp and pinch forces and the ReJoyce automated hand function test (RAHFT). Results. ARAT scores improved more after ReJoyce ET (13.0% ± 9.8%) than after conventional ET (4.0% ± 9.6%; F = 10.6, P < .01). RAHFT scores also improved more after ReJoyce ET (16.9% ± 8.6%) than conventional ET (3.3% ± 10.2%; F = 20.4, P < .01). Conclusions. FES-ET on a workstation, supervised over the Internet, is feasible and may be effective for patients who can meet the residual motor function requirements of our study.

Locomotor-Related Networks in the Lumbosacral Enlargement of the Adult Spinal Cat: Activation Through Intraspinal Microstimulation

It is commonly accepted that locomotor-related neuronal circuitry resides in the lumbosacral spinal cord. Pharmacological agents, epidural electrical stimulation, and sensory stimulation can be used to activate these intrinsic networks in in vitro neonatal rat and in vivo cat preparations. In this study, we investigated the use of low-level tonic intraspinal microstimulation (ISMS) as a means of activating spinal locomotor networks in adult cats with complete spinal transections. Trains of low-amplitude electrical pulses were delivered to the spinal cord via groups of fine microwires implanted in the ventral horns of the lumbosacral enlargement. In contrast to published reports, tonic ISMS applied through microwires in the caudal regions of the lumbosacral enlargement (L7-S1) was more effective in eliciting alternating movements in the hindlimbs than stimulation in the rostral regions. Possible mechanisms of action of tonic ISMS include depolarization of locally oscillating networks in the lumbosacral cord, backfiring of primary afferents, or activation of propriospinal neurons

First Permanent Implant of Nerve Stimulation Leads Activated by Surface Electrodes, Enabling Hand Grasp and Release The Stimulus Router Neuroprosthesis

Background. More than 150 000 neuroprostheses (NPs) have been implanted in people to restore bodily function in a variety of neural disorders. The authors developed a novel NP, the Stimulus Router System (SRS), in which only passive leads are implanted. Each lead picks up a portion of the current delivered through the skin by an external stimulator. Objective. The authors report on the first human implant of an SRS. Methods. The recipient was a tetraplegic man with bilateral hand paralysis. Three SRS leads were implanted in his right forearm to activate the finger extensors, finger flexors, and thumb flexor. A wristlet containing a surface stimulator and electrodes was used to pass trains of electrical pulses through the skin to each lead. Hand opening and grasp were controlled via a wireless earpiece that sensed small tooth-clicks and transmitted signals to the wristlet. Results. The current required to activate the muscles was less than half that required prior to implantation and below perceptual threshold. Maximal grip force and hand opening aperture were both larger using the SRS. The implanted leads have remained functional for 3 years. The recipient reported various tasks of daily life that improved during SRS usage. An electronic counter revealed mean monthly usage of 18.5 hours, equivalent to 55 hours of continuous manual activity. Conclusions. This first implant of the SRS indicates that it can be effective and reliable and has potential to provide an alternative to existing NPs.

A Fully Automated, Quantitative Test of Upper Limb Function

ABSTRACT. The Rehabilitation Joystick for Computerized Exercise (ReJoyce, Rehabtronics Inc., Edmonton, Alberta, Canada), is a workstation on which participants exercise dexterous movement tasks in the guise of computer games. The system incorporates the ReJoyce Arm and Hand Function Test (RAHFT). Here the authors evaluate the RAHFT against the Action Research Arm Test (ARAT) and the Fugl-Meyer Assessment (FMA). All 3 tests were performed in 36 separate sessions in 13 tetraplegic individuals. Concurrent and criterion validities of the RAHFT were supported by a high level of correlation with the ARAT (r2 = .88). Regarding responsiveness, the effect size of the RAHFT at week 6 of 1 hr/day exercise training was 1.8. Regarding reliability, the mean test–retest difference in RAHFT baseline scores was 0.67% ± 3.6%, which was not statistically significant. The RAHFT showed less ceiling effect than either ARAT or FMA. These data help validate the RAHFT as a quantitative, automated alternative to the ARAT and FMA. The RAHFT is the first comprehensive test of arm and dexterous hand function that does not depend on human judgment. It offers a standardized, quantitative outcome evaluation, which can be performed not only in the clinic, but also in the participants home, administered by a remote therapist over the Internet.

Fully-automated test of upper-extremity function

With the advent of new approaches to upper extremity recovery after stroke and spinal cord injury, the quantitative evaluation of hand function has become a crucial component of outcome evaluation. Recently we developed a workstation, the ReJoyce (Rehabilitation Joystick for Computer Exercise) on which subjects perform a variety of movement tasks while playing computer games. An important feature of the system is the ReJoyce Automated Hand Function Test (RAHFT). In this study we compared and validated the RAHFT against two widely-used clinical tests, the Action Research Arm Test (ARAT) [1][2] and the Fugl-Meyer Assessment (FMA) [3]. All three tests were performed in 34 separate sessions in 13 tetraplegic individuals. Principal component and regression analyses revealed that both the ARAT and the RAHFT correlated well with the first principle component fitted to the scores of the three tests. The FMA was less well correlated. These data help validate the RAHFT as a quantitative, automated alternative to the ARAT and FMA. The RAHFT is the first comprehensive test of hand function that does not depend on human judgment.

Technology improves upper extremity rehabilitation.

Stroke survivors with hemiparesis and spinal cord injury (SCI) survivors with tetraplegia find it difficult or impossible to perform many activities of daily life. There is growing evidence that intensive exercise therapy, especially when supplemented with functional electrical stimulation (FES), can improve upper extremity function, but delivering the treatment can be costly, particularly after recipients leave rehabilitation facilities. Recently, there has been a growing level of interest among researchers and healthcare policymakers to deliver upper extremity treatments to people in their homes using in-home teletherapy (IHT). The few studies that have been carried out so far have encountered a variety of logistical and technical problems, not least the difficulty of conducting properly controlled and blinded protocols that satisfy the requirements of high-level evidence-based research. In most cases, the equipment and communications technology were not designed for individuals with upper extremity disability. It is clear that exercise therapy combined with interventions such as FES, supervised over the Internet, will soon be adopted worldwide in one form or another. Therefore it is timely that researchers, clinicians, and healthcare planners interested in assessing IHT be aware of the pros and cons of the new technology and the factors involved in designing appropriate studies of it. It is crucial to understand the technical barriers, the role of telesupervisors, the motor improvements that participants can reasonably expect and the process of optimizing IHT-exercise therapy protocols to maximize the benefits of the emerging technology.

Tele-Supervised FES-Assisted Exercise for Hemiplegic Upper Limb

Stroke survivors often have upper limb (UL) hemiparesis, limiting their ability to perform activities of daily life (ADLs). Intensive, task-oriented exercise therapy (ET) can improve UL function, but motivation to perform sufficient ET is difficult to maintain. Here, we report on a trial in which a workstation was deployed in the homes of chronic stroke survivors to enable tele-coaching of ET in the guise of computer games. Participants performed six weeks of 1 h/day, five days/week ET. Hand opening and grasp were assisted with functional electrical stimulation (FES). The primary outcome measure was the Action Research Arm Test (ARAT). Secondary outcome measures included a quantitative test of UL function performed on the workstation, grasp force measurements and transcranial magnetic stimulation (TMS). Improvements were seen in the functional tests, but surprisingly, not in the TMS responses. An important finding was that participants commencing with intermediate functional scores improved the most. Conclusions: 1) Daily, tele-supervised FES-ET in chronic stroke survivors is feasible with commercially-available technology. 2) The intervention can significantly improve UL function, particularly in people who start with an intermediate level of function. 3) Significant improvements in UL function can occur in the absence of changes in TMS responses.

First permanent human implant of the Stimulus Router System, a novel neuroprosthesis: Preliminary testing of a polarity reversing stimulation technique

Neuroprostheses (NPs) are electrical stimulators that help to restore sensory or motor functions lost as a result of neural damage. The Stimulus Router System (SRS) is a new type of NP developed in our laboratory. The system uses fully implanted, passive leads to “capture” and “route” some of the current flowing between pairs of surface electrodes to the vicinity of the target nerves, hence eliminating the need for an implanted stimulator. In June 2008, 3 SRS leads were implanted in a tetraplegic man for restoration of grasp and release. To reduce the size of the external wristlet and thereby optimize usability, we recently implemented a polarity reversing stimulation technique that allowed us to eliminate a reference electrode. Selective activation of three target muscles was achieved by switching the polarities of the stimulus current delivered between pairs of surface electrodes located over the pick-up terminals of the implanted leads and reducing the amplitude of the secondary phases of the stimulus pulses.