"Task-oriented" exercise improves hamstring strength and spastic reflexes in chronic stroke patients.

BACKGROUND AND PURPOSE: Despite the belief that after cerebral infarction only limited functional gains are possible beyond the subacute period, we tested the hypothesis that a 12-week program of "task-oriented" treadmill exercise would increase muscle strength and decrease spastic reflexes in chronic hemiparetic patients. METHODS: Fourteen subjects, aged 66+/-3 (mean+/-SEM) years, with residual gait deviations due to remote stroke (>6 months), underwent repeated measures of reflexive and volitional (concentric and eccentric) torque with use of isokinetic dynamometry on the hamstring musculature bilaterally. Torque output was measured at 4 angular velocities (30(o), 60(o), 90(o), and 120(o)/s). RESULTS: After 3 months of 3 times/wk low-intensity aerobic exercise, there were significant main effects (2 legs [P<0.01]x2 times [P<0. 01]x4 angular velocities [P<0.05]) for concentric torque production. Torque/time production in the concentric mode also improved significantly in the paretic (50%, P<0.01) and nonparetic hamstrings (31%, P<0.01). Eccentric torque/time production increased by 21% (P<0.01) and 22% (P<0.01) in the paretic and nonparetic hamstrings, respectively. Passive (reflexive) torque/time generation in the paretic hamstrings decreased by 11% (P<0.027). Reflexive torque/time was unchanged in the nonparetic hamstrings (P=0.45). CONCLUSIONS: These findings provide evidence that progressive treadmill aerobic exercise training improves volitional torque and torque/time generation and reduces reflexive torque/time production in the hemiparetic limb. Strength changes associated with improved functional mobility in chronic hemiparetic stroke survivors after treadmill training will be reported in future articles.     

Training and exercise to drive poststroke recovery

To make practical recommendations regarding therapeutic strategies for the rehabilitation of patients with hemiparetic stroke, it is important to have a general understanding of the fundamental mechanisms underlying the neuroplasticity that is induced by skills training and by exercise programs designed to increase muscle strength and cardiovascular fitness. Recent clinical trials have provided insights into methods that promote adaptations within the nervous system that correlate with improved walking and upper extremity function, and that can be instigated at any time after stroke onset. Data obtained to date indicate that patients who have mild to moderate levels of impairment and disability can benefit from interventions that depend on repetitive task-oriented practice at the intensity and duration necessary to reach a plateau in a reacquired skill. Studies are underway to lessen the consequences of more-severe motor deficits by drawing on medications that augment plasticity, biological interventions that promote neural repair, and strategies that employ electrical stimulation and robotics.     

Effects of aerobic treadmill training on gait velocity, cadence, and gait symmetry in chronic hemiparetic stroke: a preliminary report

It is widely assumed that only limited improvement in functional mobility is possible beyond the subacute period following ischemic stroke. Contrary to this notion, we studied "neurologically plateaued" stroke patients with chronic hemiparesis to assess whether a "task-oriented" treadmill-training regimen would improve walking speed, cadence, and gait cycle symmetry on a modified "Get-Up and Go" task. Five male patients with a mean age of 60.4 +/- 2.7 years (mean +/- S.D.) status post ischemic stroke (> 6 months prior) participated in this nonrandomized low-intensity treadmill exercise pilot study three times/week for 3 months. All patients had mild to moderate gait asymmetries due to residual hemiparesis. Patients were videotaped before and after 3 months of treadmill aerobic exercise (AEX) while performing a functional task consisting of arising from a chair, walking 3.1 m without an assistive device as fast as safely possible, and returning to sit. Gait events were timed using a 2-D Peak Motus video analysis system. After 3 months AEX training, times for the overall "get-up and return-to-sit" (GURS) task and the "straight-away walk" (SAW) segment decreased from 8.2 +/- 1.4 sec to 6.5 +/- 0.8 sec (mean +/- SEM) (p < 0.05), and from 3.7 +/- 1 sec to 2.8 +/- 0.7 sec (p < 0.05), respectively. These data represent improvements of 21% and 24% for the GURS and SAW segments, respectively. Mean velocity increased from 0.9 +/- 0.2 to 1.2 +/- 0.21 m/sec, a 33% improvement (p < 0.01). Mean cadence (steps/min) increased from 89 +/- 9 to 97 +/- 8, a 9% increase (p < 0.05). Mean stance and swing duration diminished for both paretic (P) and nonparetic (NP) limbs, and the intralimb stance/swing ratio values moved toward normal for both the paretic and nonparetic limbs. However, these latter changes reached significance only for the P limb. Interlimb stance symmetry was unchanged. The more impaired subjects experienced the greatest gains in gait velocity and temporal measures. Collectively, these findings indicate that treadmill exercise improves functional overground mobility in individuals with chronic, stable hemiparesis.     

Motor recovery strategies after stroke

Impaired motor function after stroke is a major cause of disability in young stroke survivors. The plasticity of the adult human brain provides opportunities to enhance traditional rehabilitation programs for these individuals. Younger stroke patients appear to have a greater ability to recover from stroke and are likely to benefit substantially from treatments that facilitate plasticity-mediated recovery. The use of new exercise treatments, such as constraint-induced movement therapy, robot-aided rehabilitation, and partial body weight supported treadmill training are being studied intensively and are likely to ultimately be incorporated into standard poststroke rehabilitation. Medications to enhance recovery, growth factors, and stem cells will also be components of rehabilitation for the young stroke survivor in the foreseeable future.     

New directions in occupational therapy: implementation of the task-oriented approach in conjunction with cortical stimulation after stroke

Chronic upper extremity hemiparesis following stroke is a significant impairment that can limit a person's independence in all aspects of ADL, IADL, and functional mobility. Although recovery of functional independence may be more efficient using traditional compensatory techniques, these therapeutic methods often do not encourage integration of the hemiparetic arm and hand. In contrast, the task-oriented approach to motor recovery of poststroke hemiparesis emphasizes integration of the impaired limb into all functional tasks via skill-based training. Cortical changes have been documented following skill-based training of the upper limb in the healthy animal model. Additionally, the combination of subthreshold cortical stimulation combined with skill-based forelimb training in the induced-stroke rat model has demonstrated better outcomes than training alone. Preliminary research with human stroke survivors using task-oriented training and subthreshold cortical stimulation has shown promising results. The purpose of this article is to introduce an upper limb training protocol that was used in a national multisite trial that compares cortical stimulation in conjunction with taskoriented training to training alone.     

Motor rehabilitation after traumatic brain injury and stroke - Advances in assessment and therapy

A long-term goal in motor rehabilitation is that treatment is not selected on the basis of 'schools of thought', but rather, based on knowledge about efficacy and effectiveness of specific interventions for specific situations (e.g. functional syndromes). Motor dysfunction after stroke or TBI can be caused by many different functional syndromes such as paresis, ataxia, deafferentaion, visuo-perceptual deficits, or apraxia. Examples are provided showing that theory-based analysis of motor behavior makes it possible to describe 'syndrome-specific motor deficits'. Its potential implications for motor rehabilitation are that our understanding of altered motor behavior as well as specific therapeutic approaches might be promoted. A methodological prerequisite for clinical trials in rehabilitation is knowledge about test properties of assessment tools in follow-up situations such as test-retest reliability and responsiveness to change. Test-retest reliability assesses whether a test can produce stable measures with test repetition, while sensitivity to change reflects whether a test detects changes that occur over time. Exemplifying these considerations, a reliability and validity study of a kinematic arm movement analysis is summarized. In terms of new therapeutic developments, two examples of clinical therapeutic studies are provided assessing the efficacy of specific inter-ventions for specific situations in arm and gait rehabilitation: the Arm Ability Training for high functioning hemiparetic stroke and TBI patients, and the treadmill training for non-ambulatory hemiparetic patients. In addition, a new technical development, a machine-controlled gait trainer ist introduced.     

Motor rehabilitation after traumatic brain injury and stroke - Advances in assessment and therapy

A long-term goal in motor rehabilitation is that treatment is not selected on the basis of 'schools of thought', but rather, based on knowledge about efficacy and effectiveness of specific interventions for specific situations (e.g. functional syndromes). Motor dysfunction after stroke or TBI can be caused by many different functional syndromes such as paresis, ataxia, deafferentaion, visuo-perceptual deficits, or apraxia. Examples are provided showing that theory-based analysis of motor behavior makes it possible to describe 'syndrome-specific motor deficits'. Its potential implications for motor rehabilitation are that our understanding of altered motor behavior as well as specific therapeutic approaches might be promoted. A methodological prerequisite for clinical trials in rehabilitation is knowledge about test properties of assessment tools in follow-up situations such as test-retest reliability and responsiveness to change. Test-retest reliability assesses whether a test can produce stable measures with test repetition, while sensitivity to change reflects whether a test detects changes that occur over time. Exemplifying these considerations, a reliability and validity study of a kinematic arm movement analysis is summarized. In terms of new therapeutic developments, two examples of clinical therapeutic studies are provided assessing the efficacy of specific inter-ventions for specific situations in arm and gait rehabilitation: the Arm Ability Training for high functioning hemiparetic stroke and TBI patients, and the treadmill training for non-ambulatory hemiparetic patients. In addition, a new technical development, a machine-controlled gait trainer ist introduced.     

Robot-assisted gait training for patients with hemiparesis due to stroke

Robot-assisted devices are becoming a popular alternative to manual facilitation in stroke rehabilitation. These devices have the potential to reduce therapist burden and treatment costs; however, their effectiveness in terms of functional recovery remains in question. This pilot study compared the outcomes of a stroke rehabilitation program that incorporates robot-assisted gait training (RAGT) with a more traditional therapy program that does not. Twenty hemiparetic stroke patients were recruited at a rehabilitation hospital in Houston, Texas, and were randomly assigned to 2 groups. The control group (n = 10) received 24 1-hour sessions of conventional physical therapy, whereas the RAGT group (n = 10) received 24 1-hour sessions of conventional physical therapy combined with RAGT on a treadmill. Gait function was assessed before and after treatment by an 8-m walk test, a 3-minute walk test, and the Tinetti balance assessment. Both groups showed significant improvement in all 3 outcome measures following treatment (P < .05), but there was no difference between groups. It is concluded that RAGT may provide improvements in balance and gait comparable with conventional physical therapy. A larger multicenter trial is required to investigate the effectiveness of RAGT in hemiparetic stroke.     

Gait training in hemiplegia

Restoration of gait is a major goal in neurological rehabilitation. Before starting therapy, a comprehensive assessment is necessary to evaluate the deficits and remaining functions. A wide variety of therapeutic procedures are available and have to be adapted to the individual situation – different concepts of physiotherapy stress different features like: force exercise, reduction of spasticity, gait symmetry, utilization of equilibrium reflexes, stepping automation, endurance training, repetition of rhythmic movements, etc. The spectrum of available therapies was recently widened by treadmill training, with partial body-weight support, locomotor pharmacotherapy, selective reduction of spasticity by botulinum toxin injections, and by musical biofeedback, which have each proved to be successful in the restoration of gait pattern. Treadmill training based on partial body weight support, combined with enforced stepping movements has proved to be successful in the restoration of gait pattern. A common problem in hemiparetic gait, is the spastic inversion of the foot. If spasticity is not severe, an ankle-foot orthosis (AFO) is the appropriate technical aid. In other cases, botulinum toxin injection into spastic leg muscles has been successfully used to improve gait functions. In hemiparetic stroke patients, auditory (musical) rhythm, as a peripheral pacing signal, resulted in a significant increase in weight-bearing stance time on the paretic side. In addition, there was an improved stride symmetry with rhythmic cueing and a normalizations of gait pattern. These methods directed to gait improvement should be combined and adapted to the individual patient's needs, in order to obtain the best results.     

The role of technology in task-oriented training in persons with subacute stroke: a randomized controlled trial

This trial compares the effects of task-oriented physical therapy (PT) provided with and without the use of rehabilitation technology on locomotor recovery in 63 persons with subacute stroke. Participants in the experimental (EXP) group used a treadmill, a Kinetron isokinetic exerciser, and a limb-load monitor, whereas those in the control (CTL) group did not while engaging in PT 1 h per day, 5 days per week for 2 months. Locomotor recovery was assessed by clinical (gait speed, Fugl Meyer motor leg and arm subscores, the Balance Scale, the Timed Up and Go, and the Barthel ambulation subscore) and laboratory outcomes (gait kinematics and kinetics) pre- and posttherapy and 3 months later. Within groups, gait speed (P < 0.01) and all secondary measures improved posttherapy (P < 0.01-0.05), and improvements in clinical measures were maintained at follow-up, but there was no difference between groups (P > 0.05). When the groups were pooled, the increase in gait speed was associated (r = 0.52, P = 0.003) with an increase in ankle power generation of the affected leg. The results demonstrate that the efficacy of the task-oriented approach is not dependent on rehabilitation technology.     

Gait improvement after treadmill training in ischemic stroke survivors A critical review of functional MRI studies

Stroke survivors often present with abnormal gait, movement training can improve the walking performance post-stroke, and functional MRI can objectively evaluate the brain functions before and after movement training. This paper analyzes the functional MRI changes in patients with ischemic stroke after treadmill training with voluntary and passive ankle dorsiflexion. Functional MRI showed that there are some changes in some regions of patients with ischemic stroke including primary sensorimotor cortex, supplementary motor area and cingulate motor area after treadmill training. These findings suggest that treadmill training likely improves ischemic stroke patients’ lower limb functions and gait performance and promotes stroke recovery by changing patients’ brain plasticity; meanwhile, the novel treadmill training methods can better training effects.     

Endurance exercise facilitates relearning of forelimb motor skill after focal ischemia

Endurance exercise (i.e. running), by up-regulating brain-derived neurotrophic factor (BDNF) and other modulators of synaptic plasticity, improves attention and learning, both critical components of stroke rehabilitation. We hypothesized that, following middle cerebral artery occlusion in male Sprague-Dawley rats, endurance exercise would act synergistically with a challenging skilled forelimb task to facilitate motor recovery. Animals were randomly assigned to one of four rehabilitation conditions: no rehabilitation, running only, reach training only, and reach training preceded by running (run/reach training) for 5 weeks beginning 5 days after stroke. The behavioral outcome, morphological change and mRNA expression of proteins implicated in neuroplasticity (BDNF, synapsin I and microtubule-associated protein 2) were compared. Endurance exercise on a motorized running wheel, prior to reach training, enhanced recovery of skilled reaching ability but did not transfer to gross motor skills such as postural support (forelimb asymmetry test) and gait (ladder rung walking test). Microtubule-associated protein 2 staining density in the run/reach group was slightly enhanced in the contralateral motor cortex compared with the contralateral sensory and ipsilateral cingulate cortices, suggesting that running preceding reach training may have resulted in more dendritic branching within the motor cortex in this group. No significant differences in mRNA levels were detected among the training paradigms; however, there was a trend toward greater BDNF and synapsin I mRNA in the reaching groups. These findings suggest that exercise facilitates learning of subsequent challenging reaching tasks after stroke, which has the potential to optimize outcomes in patients with stroke.     

Upper and lower extremity robotic devices for rehabilitation and for studying motor control

PURPOSE OF REVIEW: The successful motor rehabilitation of stroke, traumatic brain-injured and spinal cord-injured patients requires an intensive and task-specific therapy approach. Budget constraints limit a hand-to-hand therapy approach, so that intelligent machines may offer a solution to promote motor recovery and obtain a better understanding of motor control. This new field of automated or robot-assisted motor rehabilitation has emerged since the 1990s. RECENT FINDINGS: This article will present clinically viable devices for upper and lower extremity rehabilitation. The MIT-Manus and the Mirror-Image Motion Enabler robot, which enable unrestricted unilateral or bilateral shoulder and elbow movement, consistently proved superior on the motor impairment level. The ARM guide, which assisted reaching in a straight-line trajectory, and the Bi-Manu-Track, which enabled the bilateral practice of a forearm and wrist movement, are currently being tested. For gait rehabilitation after stroke, the electromechanical gait trainer, GT I, has proved effective compared with treadmill training with body weight support. The Lokomat, consisting of a treadmill and a powered exoskeleton, lessened the therapeutic effort compared with manually assisted treadmill training in spinal cord-injured patients. Future developments will see more degrees of freedom, improved man-machine interaction and the implementation of virtual reality. SUMMARY: Technical possibilities are one aspect, but multi-centre trials and a consideration of the unsubstantiated fears among therapists of being replaced by machines will decide on the successful implementation of this most promising field to the benefit of patients.     

Recovery of gait and other motor functions after stroke: novel physical and pharmacological treatment strategies

The gait-lab at Klinik Berlin developed and evaluated novel physical and pharmacological strategies promoting the repetitive practise of hemiparetic gait in line with the slogan: who wants to relearn walking, has to walk. Areas of research are treadmill training with partial body weight support, enabling wheelchair-bound subjects to repetitively practice gait, the electromechanical gait trainer GT I reducing the effort on the therapists as compared to the manually assisted locomotor therapy, and the future HapticWalker which will allow the additional practise of stair climbing up and down and of perturbations. Further means to promote gait practice after stroke was the application of botulinum toxin A for the treatment of lower limb spasticity and the early use of walking aids. New areas of research are also the study of D-Amphetamine, which failed to promote motor recovery in acute stroke patients as compared to placebo, and the development of a computerized arm trainer, Bi-Manu-T rack, for the bilateral treatment of patients with a severe upper limb paresis.     

Advances in adjuvant pharmacotherapy for motor rehabilitation: effects of levodopa

Hemiparesis is common after stroke and often severely disabling. Until very recently, the only therapeutic option for motor recovery was physiotherapeutic training. Experimental animal studies have shown that when applied in addition to exercises pharmacological interventions that affect the norepinephrine system can enhance the rate of functional motor recovery. These effects were observed when an increase in norepinephrine concentration in the CNS was pharmacologically induced. We recently showed that 3 weeks of single daily doses of 100 mg L-dopa, which is metabolized into norepinephrine in the brain, increase the efficacy of physiotherapy in hemiparetic stroke patients. Two additional randomized controlled trials with stroke patients also demonstrated the clinical relevance of this approach for motor recovery and independence in activities of daily living. Modifying effects of other frequently occurring clinical symptoms such as spasticity, neglect, and attention were also investigated. Thus, in view of its minimal side effects, L-dopa can be recommended in conjunction with exercise therapy to improve the functional outcome in stroke rehabilitation.     

Aerobic Training Efficacy in Inflammation,Neurotrophins, and Function in Chronic Stroke Persons: A Randomized Controlled Trial Protocol

Background: Neuroinflammation is an important part of stroke pathophysiology and has both detrimental and beneficial effects after stroke. Besides that the enhancement of neurotrophins seems to be related to improvements in stroke recovery. Evidences suggest that exercise plays a role in modulating anti-inflammatory and neurotrophic effects. However, little is known about its impact in stroke survivors, mainly in chronic stroke. The purpose of this study is to investigate the efficacy of moderate-intensity treadmill exercise in changing inflammatory mediators, interleukin-6 (IL-6), soluble tumor necrosis factor receptors I and II (sTNFRI, sTNFRII), interleukin-10 (IL-10), and brain-derived neurotrophic factor (BDNF) levels in chronic stroke patients. The secondary objective is to investigate the effects of training in improve mobility and exercise capacity. Methods: This is a randomized controlled trial. Chronic stroke patients will be randomized to an experimental or control group, and will receive group interventions three times per week, over 12 weeks. The experimental group will receive moderate-intensity (60%-80% of maximum heart rate reserve) treadmill exercise. Control group will perform walking training on the ground (<40% of maximum heart rate reserve). Primary outcomes include IL-6, sTNFRI, sTNFRII, IL-10, and BDNF levels. Secondary outcomes include mobility and exercise capacity. Outcomes will be measured at baseline, postintervention, and at the 4-week follow-up. Discussion: The findings of this trial have the potential to provide important insights regarding the effects of an aerobic physical program in the inflammatory process and in the neuronal plasticity in stroke persons and its impact on mobility and exercise capacity.     

Motor response to amphetamine treatment, task-specific training, and limited motor experience in a postacute animal stroke model

Despite advances in acute treatment of ischemic cerebrovascular events, the most common clinical outcome is disabling neurological impairment. Despite experimental evidence that psychostimulant treatment can positively affect recovery rate after focal brain lesions, beyond rehabilitation therapies there are no currently accepted medical treatments indicated for diminishing neurological impairment after clinically established stroke. To test the effect of amphetamine, task-specific training, limiting motor experience, and their interaction on motor recovery in a postacute animal model of stroke, animals were nonaversively trained in beam walking before a unilateral photochemical sensorimotor cortex lesion and tested for 10 days after lesion. Animals were randomized to groups receiving: a single session of motor training 24 h after lesion; a single injection of amphetamine 2 mg/kg 24 h after lesion; beam-walking experience limited to testing on days 1 and 10 after lesion; and groups that received amphetamine treatment combined with training or combined with limited experience. Motor recovery was maximally enhanced by training, delayed by amphetamine treatment, and most negatively affected by limiting beam-walking experience during the recovery period. These findings support physical training after stroke, indicating that limiting physical activity negatively affects motor recovery and raises questions about the role of stimulant treatment to enhance motor recovery in the postacute phase after stroke.     

The use of a treadmill with biofeedback function in assessment of relearning walking skills in post-stroke hemiplegic patients--a preliminary report

Background and purposeOne of the most important goals of rehabilitation of post-stroke hemiplegic patients is the recovery of their locomotion function. The aim of the study was to assess walking function recovery by means of in-patient rehabilitation procedures, as well as the effectiveness of treadmill gait training with the use of biological feedback.Material and methodsThe research involved groups of chronic post-stroke hemiplegic patients receiving treatment in the rehabilitation ward. Factors under scrutiny included walking speed and capacity, number of steps, weight bearing symmetry for lower extremities while standing, lower limb mobility on the Brunnström scale, and muscle tone on the Ashworth Scale. The study group patients followed a rehabilitation regime that included treadmill training aided with biofeedback function. Each study group participant exercised every day (a total of 15 times), with a single practice time ranging from 5 to 20 minutes. Control patients followed a rehabilitation regime without the additional treadmill exercises.ResultsPatients in both groups demonstrated improvement in locomotion abilities. In the group following the physiotherapy regime supplemented with treadmill training with the use of biofeedback, the measures of walking speed, weight bearing symmetry for lower extremities, and number of steps were better than in controls.ConclusionsTreadmill gait training with the use of biofeedback is effective for relearning locomotion functions in post-stroke hemiplegic patients and can constitute a significant type of exercise in a physiotherapy regime.