Revisiting Poststroke Upper Limb Stratification: Resilience in a Larger Cohort.

Background: Upper limb (UL) impairment in stroke survivors is both multifactorial and heterogeneous. Stratification of motor function helps identify the most sensitive and appropriate assessments, which in turn aids the design of effective and individualized rehabilitation strategies. We previously developed a stratification method combining the Grooved Pegboard Test (GPT) and Box and Block Test (BBT) to stratify poststroke UL motor function.

Improved Kinematics and Motor Control in a Longitudinal Study of a Complex Therapy Movement in Chronic Stroke.

Impaired motor control post-stroke is typically measured using clinical assessments employing categorical and subjective scoring. We investigated quantitative kinematic parameters of a complex movement with therapy in chronic stroke. Tri-axial accelerometry of the more-affected arm of 24 patients was recorded during early- (day 2-3) and late- (days 12-14) therapy, and for 13 patients at 6-month follow-up.

A Longitudinal Electromyography Study of Complex Movements in Poststroke Therapy. 1: Heterogeneous Changes Despite Consistent Improvements in Clinical Assessments.

Poststroke weakness on the more-affected side may arise from reduced corticospinal drive, disuse muscle atrophy, spasticity, and abnormal coordination. This study investigated changes in muscle activation patterns to understand therapy-induced improvements in motor-function in chronic stroke compared to clinical assessments and to identify the effect of motor-function level on muscle activation changes. Electromyography (EMG) was recorded from five upper limb muscles on the more-affected side of 24 patients during early and late therapy sessions of an intensive 14-day program of Wii-based Movement Therapy (WMT) and for a subset of 13 patients at 6-month follow-up.

A Longitudinal Electromyography Study of Complex Movements in Poststroke Therapy. 2: Changes in Coordinated Muscle Activation.

Fine motor control is achieved through the coordinated activation of groups of muscles, or "muscle synergies." Muscle synergies change after stroke as a consequence of the motor deficit. We investigated the pattern and longitudinal changes in upper limb muscle synergies therapy in a largely unconstrained movement in patients with a broad spectrum of poststroke residual voluntary motor capacity.

Targeted upper-limb Wii-based Movement Therapy also improves lower-limb muscle activation and functional movement in chronic stroke.

Purpose: Post-stroke hemiparesis may manifest as asymmetric gait, poor balance, and inefficient movement patterns. We investigated improvements in lower-limb muscle activation and function during Wii-based Movement Therapy (WMT), a rehabilitation program specifically targeting upper-limb motor-function.

Methods: Electromyography (EMG) was recorded bilaterally from tibialis anterior (TA) in 20 stroke patients during a 14-day WMT program.

BDNF Genotype Interacts with Motor Function to Influence Rehabilitation Responsiveness Poststroke.

Background: Persistent motor impairment is common but highly heterogeneous poststroke. Genetic polymorphisms, including those identified on the brain-derived neurotrophic factor (BDNF) and apolipoprotein E (APOE) genes, may contribute to this variability by limiting the capacity for use-dependent neuroplasticity, and hence rehabilitation responsiveness.

Objective: To determine whether BDNF and APOE genotypes influence motor improvement facilitated by poststroke upper-limb rehabilitation.

Cardiovascular fitness is improved post-stroke with upper-limb Wii-based Movement Therapy but not dose-matched constraint therapy.

Introduction: Post-stroke cardiovascular fitness is typically half that of healthy age-matched people. Cardiovascular deconditioning is a risk factor for recurrent stroke that may be overlooked during routine rehabilitation. This study investigated the cardiovascular responses of two upper limb rehabilitation protocols.

Cortical beta oscillations and motor thresholds differ across the spectrum of post-stroke motor impairment, a preliminary MEG and TMS study.

Background: Cortical oscillatory activity in the beta frequency band (13-30Hz) is associated with voluntary movement and may be altered in motor disorders such as stroke.

Methods: We used a multimodal case-series approach to investigate movement-related beta oscillations, cortical excitability and upper-limb motor-function in 10 chronic stroke-patients across a broad range of motor-impairment. Assessments included: (i) whole-head magnetoencephalography (MEG) during a voluntary motor task; (ii) resting and active motor-thresholds to transcranial magnetic stimulation (TMS); and (iii) assessments of upper-limb motor-function.

The efficacy of Wii-based Movement Therapy for upper limb rehabilitation in the chronic poststroke period: a randomized controlled trial.

Background: More effective and efficient rehabilitation is urgently needed to address the prevalence of unmet rehabilitation needs after stroke. This study compared the efficacy of two poststroke upper limb therapy protocols.

Aims And/or Hypothesis: We tested the hypothesis that Wii-based movement therapy would be as effective as modified constraint-induced movement therapy for post-stroke upper-limb motor rehabilitation.

Voluntary Activation is Reduced in Both the More- and Less-Affected Upper Limbs after Unilateral Stroke.

Objective: Measurement of voluntary activation gives an indication of neural drive to the muscle. This study aimed to identify the site of impairment in neural drive during voluntary contractions post-stroke.

Methods: Elbow-flexor voluntary activation was assessed bilaterally for 10 stroke patients (mean 61.

Comparison of three tools to measure improvements in upper-limb function with poststroke therapy.

Background: Functional ability is regularly monitored poststroke to assess improvement and the efficacy of clinical trials. The balance between implementation times and sensitivity has led to multidomain tools that aim to assess upper-limb function comprehensively.

Objective: This study implemented 3 common multidomain tools to investigate their suitability across a broad spectrum of movement ability after stroke.

The prevalence and magnitude of impaired cutaneous sensation across the hand in the chronic period post-stroke.

Sensation is commonly impaired immediately post-stroke but little is known about the long-term changes in cutaneous sensation that have the capacity to adversely impact independence and motor-function. We investigated cutaneous sensory thresholds across the hand in the chronic post-stroke period. Cutaneous sensation was assessed in 42 community-dwelling stroke patients and compared to 36 healthy subjects.

Single motor unit firing rate after stroke is higher on the less-affected side during stable low-level voluntary contractions.

Muscle weakness is the most common outcome after stroke and a leading cause of adult-acquired motor disability. Single motor unit properties provide insight into the mechanisms of post-stroke motor impairment. Motor units on the more-affected side are reported to have lower peak firing rates, reduced discharge variability and a more compressed dynamic range than healthy subjects.

Two common tests of dexterity can stratify upper limb motor function after stroke.

Background: Neurological deficits after a stroke are commonly classified according to motor function for clinical decision making regarding discharge and rehabilitation. Participants in clinical stroke studies are also stratified by motor function to avoid a sampling bias.

Objective: This post hoc analysis examined a suite of upper limb functional assessment tools to test the hypothesis that motor function of survivors of stroke can be stratified using 2 simple tests of manual dexterity despite the heterogeneity of the population.

Bilateral priming before wii-based movement therapy enhances upper limb rehabilitation and its retention after stroke: a case-controlled study.

Background: Motor deficits after a stroke are thought to be compounded by the development of asymmetric interhemispheric inhibition. Bilateral priming was developed to rebalance this asymmetry and thus improve therapy efficacy.

Objective: This study investigated the effect of bilateral priming before Wii-based Movement Therapy to improve rehabilitation after stroke.

Sustained maximal voluntary contraction produces independent changes in human motor axons and the muscle they innervate.

The repetitive discharges required to produce a sustained muscle contraction results in activity-dependent hyperpolarization of the motor axons and a reduction in the force-generating capacity of the muscle. We investigated the relationship between these changes in the adductor pollicis muscle and the motor axons of its ulnar nerve supply, and the reproducibility of these changes. Ten subjects performed a 1-min maximal voluntary contraction.

Self-sustained motor activity triggered by interlimb reflexes in chronic spinal cord injury, evidence of functional ascending propriospinal pathways.

The loss or reduction of supraspinal inputs after spinal cord injury provides a unique opportunity to examine the plasticity of neural pathways within the spinal cord. In a series of nine experiments on a patient, quadriplegic due to spinal cord injury, we investigated interlimb reflexes and self-sustained activity in completely paralyzed and paretic muscles due to a disinhibited propriospinal pathway. Electrical stimuli were delivered over the left common peroneal nerve at the fibular head as single stimuli or in trains at 2-100 Hz lasting 1 s.

The magnitude and rate of reduction in strength, dexterity and sensation in the human hand vary with ageing.

Cutaneous sensation and motor performance of the hand decline with age. It is not known if motor performance declines are influenced by reductions in cutaneous sensation, or if motor performance deteriorates at a consistent rate across motor tasks. Handgrip strength, finger-tapping frequency and grooved-pegboard performance were assessed for both hands of 70 subjects (20-88 years), 10 per decade.

Games for Rehabilitation: Wii-based Movement Therapy Improves Poststroke Movement Ability.

Stroke is the leading cause of adult-acquired motor disability. The greatest impediments to poststroke rehabilitation are access and patient compliance. Wii-based Movement Therapy was developed as an alternative to conventional and virtual reality therapies to overcome issues of rehabilitation access, cost, and patient compliance.

Age-related changes in cutaneous sensation in the healthy human hand.

Cutaneous sensation deteriorates with age. It is not known if this change is consistent over the entire hand or if sensation is affected by changes in skin mechanics. Cutaneous perceptual thresholds were tested at eight sites in the glabrous skin and two in the hairy skin of both hands in 70 subjects (20-88 years), five male and five female per decade, using calibrated von Frey filaments, two-point discrimination, and texture discrimination.

The stability of M(max) and H (max) amplitude over time.

The stability of the maximal muscle response (M(max)) is critical to H reflex methodology. It has previously been reported that the amplitude of M(max) declines over time. If reproducible, this finding would have implications for all experimental studies that normalise the output of the motoneurone pool against the M wave.

Wii-based movement therapy to promote improved upper extremity function post-stroke: a pilot study.

Background: Virtual-reality is increasingly used to improve rehabilitation outcomes. The Nintendo Wii offers an in-expensive alternative to more complex systems.

Objective: To investigate the efficacy of Wii-based therapy for post-stroke rehabilitation.

Threshold behaviour of human axons explored using subthreshold perturbations to membrane potential.

The present study explores the threshold behaviour of human axons and the mechanisms contributing to this behaviour. The changes in excitability of cutaneous afferents in the median nerve at the wrist were recorded to a long-lasting subthreshold conditioning stimulus, with a waveform designed to maximize the contribution of currents active in the just-subthreshold region. The conditioning stimulus produced a decrease in threshold that developed over 3-5 ms following the end of the depolarization and then decayed slowly, in a pattern similar to the recovery of axonal excitability following a discharge.