Search

Patients with poor upper limb motor recovery after stroke are likely to develop increased resistance to passive wrist extension, i.e., wrist hyper-resistance. Quantification of the underlying neural and non-neural elastic components is of clinical interest. This cross-sectional study compared two methods: a commercially available device (NeuroFlexor (R)) with an experimental EMG-based device (Wristalyzer) in 43 patients with chronic stroke. Spearman's rank correlation coefficients (r) between components, modified Ashworth scale (MAS) and range of passive wrist extension (PRoM) were calculated with 95% confidence intervals. Neural as well as elastic components assessed by both devices were associated (r = 0.61, 95%CI: 0.38-0.77 and r = 0.53, 95%CI: 0.28-0.72, respectively). The neural component assessed by the NeuroFlexor (R) associated significantly with the elastic components of NeuroFlexor (R) (r = 0.46, 95%CI: 0.18-0.67) and Wristalyzer (r = 0.36, 95%CI: 0.06-0.59). The neural component assessed by the Wristalyzer was not associated with the elastic components of both devices. Neural and elastic components of both devices associated similarly with the MAS (r = 0.58, 95%CI: 0.34-0.75 vs. 0.49, 95%CI: 0.22-0.69 and r = 0.51, 95%CI: 0.25-0.70 vs. 0.30, 95%CI: 0.00-0.55); elastic components associated with PRoM (r = -0.44, 95%CI: -0.65- -0.16 vs. -0.74, 95%CI: -0.85- -0.57 for NeuroFlexor (R) and Wristalyzer respectively). Results demonstrate that both methods perform similarly regarding the quantification of neural and elastic wrist hyper-resistance components and have an added value when compared to clinical assessment with the MAS alone. The added value of EMG in the discrimination between neural and non-neural components requires further investigation.

Adequate positioning of an orbital implant during orbital reconstruction surgery is essential for restoration of the pre-traumatised anatomy, but visual appraisal of its position is limited by the keyhole access and protruding soft tissues. A positioning instrument that attaches to the implant was designed to provide feedback outside the orbit. The goal of this study was to evaluate the accuracy of placement with the instrument and compare it with the accuracy of placement by visual appraisal. Ten orbits in five human cadaver heads were reconstructed twice: once using visual appraisal and once using the instrument workflow. No significant improvement was found for the roll (5.8° vs 3.4°, respectively, p=0.16), pitch (2.1° vs 1.5°, p=0.56), or translation (2.9 mm vs 3.3 mm, p=0.77), but the yaw was significantly reduced if the instrument workflow was used (15.3° vs 2.9°, p=0.02). The workflow is associated with low costs and low logistical demands, and may prevent outliers in implant positioning in a clinical setting when intraoperative navigation or patient-specific implants are not available.

Objectives: Vascular anatomy of the aortic arch and supra-aortic arteries has been suggested as influencing the risk of carotid artery stenting (CAS). The expert opinion based Delphi anatomical risk (DAR) score was developed to predict difficulty of CAS in relation to procedural stroke risk, and thereby aid patient selection. The aim was to validate the DAR score in the context of a randomised clinical trial. Methods: In this post hoc analysis of the International Carotid Stenting Study (ICSS), only patients treated by CAS with available pre-procedural CT angiography (CTA) were included. Patients with tortuous anatomy unsuitable for stenting were excluded from ICSS. CTA based vascular anatomy was rated by two independent observers. Every possible combination of anatomy resulted in a risk score, divided in four categories of expected risk (low, < 5.0; low–intermediate, 5.0–5.9; high–intermediate, 6.0–6.9; high, ≥ 7.0). Binomial logistic regression was used to assess the relationship between anatomical risk score and procedural risk of any stroke. Differences between predefined age groups were also assessed. Results: A total of 275 patients were included. Interobserver reliability for all anatomical risk factors was high (κ = 0.76–0.84). In total, 16 strokes (6%) occurred in the procedural period. No significant relationship was observed between the DAR score and risk of procedural stroke, with the risk of stroke being 9% in the high risk vs. 4% in the low risk categories (p = .49). A higher mean DAR score was observed in patients ≥70 years compared with younger patients (4.6 ± 1.5 vs. 3.9 ± 1.4, p < .001), which was mainly explained by higher rates of arch atheroma (44% vs. 20%, p < .001). Prolonged intervention duration was significantly associated with increased stroke risk (11% vs. 4%, p < .04), but not with the DAR score. Conclusions: No statistically significant association was found between anatomical difficulty, as defined in the DAR score, and procedural stroke risk. However, the small sample size potentially rendered the study underpowered to detect group differences, and confirmation with a larger sample is essential.

Objective To classify patients with stroke into subgroups based on their characteristics at the moment of discharge from inpatient rehabilitation in order to predict community ambulation outcome 6 months later. Design Prospective cohort study with a baseline measurement at discharge from inpatient care and final outcome determined after 6 months. Setting Community. Participants A cohort of patients (N=243) with stroke, referred for outpatient physical therapy, after completing inpatient rehabilitation in The Netherlands. Interventions Not applicable. Main Outcome Measures A classification model was developed using Classification And Regression Tree (CART) analysis. Final outcome was determined using the community ambulation questionnaire. Potential baseline predictors included patient demographics, stroke characteristics, use of assistive devices, comfortable gait speed, balance, strength, motivation, falls efficacy, anxiety, and depression. Results The CART model accurately predicted independent community ambulation in 181 of 193 patients with stroke, based on a comfortable gait speed at discharge of 0.5 meters per second or faster. In contrast, 27 of 50 patients with gait speeds below 0.5 meters per second were correctly predicted to become noncommunity walkers. Conclusions We show that comfortable gait speed is a key factor in the prognosis of community ambulation outcome. The CART model may support clinicians in organizing community services at the moment of discharge from inpatient care.

Item does not contain fulltext BACKGROUND CONTEXT: Patients with adolescent idiopathic scoliosis (AIS) perform surprisingly well after spinal correction and fusion. It was previously hypothesized that, during gait, certain mechanisms compensate for the loss in spinal motion. Still, previous studies could not identify such compensatory mechanisms in the lower body. PURPOSE: This study aims to test the hypothesis of a compensatory increased motion of the distal unfused part of the spine during gait after posterior spinal correction and fusion. STUDY: This is a prospective gait study. PATIENTS AND METHODS: Twelve patients with AIS were included. Sets of three VICON skin markers were used to measure the 3D motion of the proximal part of the fusion in relation to the pelvis (PFP) and the distal part of the fusion in relation to the pelvis (DFP). By doing so, PFP represents the motion of the fused and unfused parts of the spine, and DFP represents the motion of the unfused part of the spine. Measurements were performed preoperatively and 3 and 12 months after posterior spinal correction and fusion. RESULTS: Surgery resulted in a decrease in PFP transversal plane range of motion (ROM) (8.3 degrees vs. 5.9 degrees , p=.006). No compensatory increase in the ROM of DFP could be identified. Actually, DFP transversal plane ROM also decreased (8.2 degrees vs. 5.6 degrees , p=.019). No improvement over time was observed when comparing the 3- and 12-month postoperative measurements. CONCLUSIONS: The hypothesis of a compensatory increase in motion of the distal unfused segments after spinal fusion for AIS is a much researched and controversial topic. This study is the first to study this hypothesis in such detail during gait and could not demonstrate such increase. 01 december 2018

Development of in-silico models of patient-specific cerebral artery networks presents several significant technical challenges: (i) The resolution and smoothness of medical CT images are much lower than the required element/cell length for FEA/CFD/FSI models; (ii) contact between vessels, and indeed self contact of high tortuosity vessel segments are not clearly identifiable from medical CT images. Commercial model construction software does not provide customised solutions for such technical challenges, with the result that accurate, efficient and automated development of patient-specific models of the cerebral vessels is not facilitated. This paper presents the development of a customised and highly automated platform for the generation of high resolution patient-specific FEA/CFD/FSI models from clinical images. This platform is used to perform the first fluid–structure-interaction patient-specific analysis of blood flow and artery deformation of an occluded cerebral vessel. Results demonstrate that in addition to flow disruption, clot occlusion significantly alters the geometry and strain distribution in the vessel network, with the blocked M2 segment undergoing axial elongation. The new computational approach presented in this study can be further developed as a clinical diagnostic tool and as a platform for thrombectomy device design.

Objectives Orthostatic hypotension (OH) and orthostatic intolerance symptoms are common in older community-dwelling adults and are associated with reduced quality of life and detrimental health outcomes. This study aimed to determine the prevalence, co-occurrence and determinants of OH and orthostatic intolerance symptoms in geriatric rehabilitation inpatients. Design Observational, longitudinal cohort, “REStORing the health of acutely unwell adulTs” (RESORT). Setting and Participants Geriatric rehabilitation inpatients (n = 1505) of a tertiary teaching hospital in Melbourne, Australia. Methods OH was defined as a drop in systolic blood pressure by ≥20 mm Hg and/or diastolic blood pressure by ≥10 mm Hg within three 3 of moving from supine to a standing or sitting position. Symptoms were recorded following the 3 minutes. Determinants included sociodemographics, reason for admission, cognitive health, nutritional status, physical performance, frailty, morbidity, medication use, length of stay (LOS), and number of geriatric conditions. Independent t-tests, Mann-Whitney U tests or χ2 tests were used to analyze differences between inpatients with and without OH and symptoms. Logistic regression analyses were used to ascertain the determinants. Results OH and orthostatic intolerance symptoms were prevalent in 19.8% (standing: 21.4%, sitting: 18.2%) and 22.6% (standing: 25.0%, sitting: 20.2%) of inpatients, respectively. Symptoms were reported by 32.8% of inpatients with OH and 20.1% without OH. Higher number of comorbidities and geriatric conditions, low functional independence, and longer LOS were determinants of OH. Female gender, higher number of morbidities and geriatric conditions, low functional independence, depression risk, poor physical performance, musculoskeletal and “other” reasons for admission, and long LOS during geriatric rehabilitation were determinants of symptoms. Conclusions and Implications OH and orthostatic intolerance symptoms occur in one-fifth of geriatric rehabilitation inpatients, however, the co-occurrence is low and determinants differ. Poorer health in patients with orthostatic intolerance symptoms highlights the need to assess symptoms in clinical practice, independent of an OH diagnosis.

Background: Physical inactivity in hospitalized older adults is highly prevalent and associated with detrimental health outcomes. Understanding its determinants is important for prognosis and tailoring interventions in geriatric rehabilitation inpatients. Methods: Within the REStORing health of acutely unwell adulTs (RESORT) observational, longitudinal cohort, geriatric rehabilitation inpatients wore an inertial sensor (ActivPAL4) for one week to objectively assess instrumented sedentary behavior (i-SB) and physical activity (i-PA). Determinants were grouped in five geriatric domains: morbidity, cognition/psychology, physical performance, functional performance, and nutritional status. Their association with i-SB (mean sitting, lying, non-upright time) and i-PA (mean number of steps, sit-to-stand transitions and upright time) quintiles were examined using multivariate ordinal logistic regression analyses with Bonferroni correction (p < 0.006). Results: A total of 145 inpatients were included (mean age 83.0, SD 7.7 years; 55.9% females). More comorbidities were associated with a lower daily number of steps (OR:0.91, 95%CI: 0.86–0.96) and lower upright time (OR:0.93, 95%CI: 0.88–0.98). Depressive symptoms (higher Hospital Anxiety and Depression Scale score) were associated with higher non-upright time (OR: 1.12, 95%CI: 1.03–1.21) and lower upright time (OR: 0.89, 95%CI: 0.83–0.96). Better physical performance (higher Functional Ambulation Classification, gait speed, and Short Physical Performance Battery score) was associated with lower i-SB measures (OR range: 0.07–0.78, p < 0.0005) and higher i-PA measures (OR range: 1.35–19.50, p < 0.0005). Higher functional performance (Katz index of Activities of Daily Living score) was associated with lower i-SB measures (OR range: 0.61–0.69, p ≤ 0.003) and higher i-PA measures (OR range: 1.60–3.64, p < 0.0005). Being malnourished was associated with lower i-PA measures (OR range: 0.29–0.32, p ≤ 0.004). Conclusions: Worse morbidity, depressive symptoms, worse physical and functional performance, and worse nutritional status were associated with higher i-SB and lower i-PA. These determinants should be taken into account while designing and promoting multidisciplinary physical activity interventions.

Purpose: Simulating low-­dose Computed Tomography (CT) facilitates in-­silico studies into the required dose for a diagnostic task. Conventionally, low-­‐dose CT images are created by adding noise to the projection data. However, in practice the raw data is often simply not available. This paper presents a new method for simulating patient-­‐specific, low-dose CT images without the needof the original projection data. Methods: The low-­dose CT simulation method included the following: (1) computation of a virtual sinogram from a high dose CT image through aradon transform; (2) simulation of a 'reduced'­‐dose sinogram with appropriateamounts of noise; (3) subtraction of the high-­‐dose virtual sinogram from thereduced-­‐dose sinogram; (4) reconstruction of a noise volume via filtered back-projection; (5) addition of the noise image to the original high-dose image. Therequired scanner-­Specific parameters, such as the apodization window, bowtiefilter, the X-ray tube output parameter (reflecting the photon flux) and the detector read-­out noise, were retrieved from calibration images of a watercylinder. The low-­‐dose simulation method was evaluated by comparing thenoise characteristics in simulated images with experimentally acquireddata.Results:The models used to recover the scanner-­specific parameters fitted accurately tothe calibration data, and the values of the parameters were comparable to valuesreported in literature. Finally, the simulated low-dose images accurately reproduced the noise characteristics in experimentally acquired low-dose­‐volumes.Conclusion:The developed methods truthfully simulate low-­dose CT imaging for a specificscanner and reconstruction using filtered backprojection. The scanner-­‐specificparameters can be estimated from calibration data.

Objective Sarcopenia is highly prevalent in hospitalized older patients and associated with short-term mortality. This study aimed to investigate whether sarcopenia and its measures handgrip strength (HGS) and muscle mass at hospital admission were associated with long-term mortality in a cohort of hospitalized older patients. Design Observational, prospective, longitudinal inception cohort study. Setting and Participants Academic teaching hospital; patients age ≥70 years admitted to the internal medicine, acute admission, trauma, or orthopedic wards. Methods HGS and muscle mass were measured at admission using a hand dynamometer and bioelectrical impedance analysis. Sarcopenia was determined based on the European Working Group on Sarcopenia in Older People definition. HGS and muscle mass (skeletal muscle mass index, appendicular lean mass, relative skeletal muscle mass) were expressed as sex-specific tertiles. The associations of sarcopenia, HGS, and muscle mass with mortality (during a follow-up of 3.4-4.1 years) were analyzed using Cox regression, adjusted for age, sex, comorbidity, and weight or height. Associations of HGS and muscle mass were stratified by sex. Results Out of 363 patients [mean age: 79.6 years (standard deviation: 6.4), 49.9% female] 49% died. Probable sarcopenia (prevalence of 53.7%) and sarcopenia (prevalence of 20.8%) were significantly associated with long-term mortality [hazard ratio (HR) 1.53, 95% confidence interval (CI) 1.08‒2.17 and 1.71 95% CI 1.12‒2.61, respectively]. Low HGS, skeletal muscle mass index, and appendicular lean mass were associated with a higher mortality risk (lowest tertile vs highest tertile: HR 2.660, 95% CI 1.40‒5.05; HR 1.95, 95% CI 1.06‒3.58 and HR 1.99 (95% CI 1.12‒3.53) in male patients. No statistically significant associations of relative muscle mass with mortality were found. Conclusions and Implications Sarcopenia and its measures (low HGS and low absolute muscle mass at admission) predict long-term mortality in older hospitalized patients.

Thrombus permeability determines blood flow through the occluding thrombus in acute ischemic stroke (AIS) patients. The quantification of thrombus permeability is challenging since it cannot be directly measured nor derived from radiological imaging data. As a proxy of thrombus permeability, thrombus perviousness has been introduced, which assesses the amount of contrast agent that has penetrated the thrombus on single-phase computed tomography angiography (CTA). We present a method to assess thrombus permeability rather than perviousness. We follow a three-step approach: (1) we propose a theoretical channel-like structure model describing the thrombus morphology. Using Darcy’s law, we provide an analytical description of the permeability for this model. According to the channel-like model, permeability depends on the number of channels in the thrombus, the radius of the occluded artery, and the void fraction representing the volume available for the blood to flow; (2) we measure intra-thrombus blood flow and velocity on dynamic CTA; and (3) we combine the analytical model with the dynamic CTA measurements to estimate thrombus permeability. Analysis of dynamic CTA data from 49 AIS patients showed that the median blood velocity in the thrombus was 0.58 (IQR 0.26–1.35) cm/s. The median flow within the thrombus was 3.48 · 10−3 (IQR 1.71 · 10−3–9.21 · 10−3) ml/s. Thrombus permeability was of the order of 10−3–10−5 mm2, depending on the number of channels in the thrombus. The channel-like thrombus model offers an intuitive way of modelling thrombus permeability, which can be of interest when studying the effect of thrombolytic drugs.

Background. Eight-and-a-half syndrome is a rare condition comprising one-and-a-half syndrome and cranial nerve VII palsy caused by a single unilateral lesion in the lower pontine tegmentum, of varying etiology. Case presentation. A 67-year-old woman presented at our emergency department with diplopia, vertigo, headache, nausea and vomiting. Physical examination revealed a left horizontal gaze palsy, left internuclear ophthalmoplegia and left facial palsy. Upon the clinical findings eight-and-a-half syndrome was suspected. Cerebral computed tomography showed no signs of recent haemorrhage or ischaemia, but MRI showed a hyperintense lesion located at the left dorsal pons, confirming the diagnosis. Conclusions. Our case illustrates the value of a thorough physical examination combined with the clinical presentation to precisely localize a single lesion causing a complex clinical syndrome.

Contains fulltext : 50635.pdf (Publisher’s version ) (Closed access) Statistical interdependencies between magnetoencephalographic signals recorded over different brain regions may reflect the functional connectivity of the resting-state networks. We investigated topographic characteristics of disturbed resting-state networks in Alzheimer's disease patients in different frequency bands. Whole-head 151-channel MEG was recorded in 18 Alzheimer patients (mean age 72.1 years, SD 5.6; 11 males) and 18 healthy controls (mean age 69.1 years, SD 6.8; 7 males) during a no-task eyes-closed resting state. Pair-wise interdependencies of MEG signals were computed in six frequency bands (delta, theta, alpha1, alpha2, beta and gamma) with the synchronization likelihood (a nonlinear measure) and coherence and grouped into long distance (intra- and interhemispheric) and short distance interactions. In the alpha1 and beta band, Alzheimer patients showed a loss of long distance intrahemispheric interactions, with a focus on left fronto-temporal/parietal connections. Functional connectivity was increased in Alzheimer patients locally in the theta band (centro-parietal regions) and the beta and gamma band (occipito-parietal regions). In the Alzheimer group, positive correlations were found between alpha1, alpha2 and beta band synchronization likelihood and MMSE score. Resting-state functional connectivity in Alzheimer's disease is characterized by specific changes of long and short distance interactions in the theta, alpha1, beta and gamma bands. These changes may reflect loss of anatomical connections and/or reduced central cholinergic activity and could underlie part of the cognitive impairment.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS), marked by infiltration of monocyte-derived macrophages in the brain parenchyma. Macrophages contribute to disease pathology by secretion of inflammatory mediators, such as reactive oxygen species (ROS). ROS are involved in various processes underlying MS pathology, including monocyte migration across the blood-brain barrier, phagocytosis and degradation of myelin, axonal degeneration, and oligodendrocyte damage. High concentrations of ROS cause oxidative stress, which induces transcriptional activation of phase II detoxification enzymes, such as the antioxidant protein NAD(P)H:quinone oxidoreductase 1 (NQO1). Since NQO1 expression may act as an indicator of oxidative stress and knowledge about the cellular distribution pattern of NQO1 in MS brains is lacking, we examined the expression of NQO1 in various well-characterized MS lesions. Here, we show for the first time that NQO1 is highly upregulated in active and chronic active MS lesions, particularly in hypertrophic astrocytes and myelin-laden macrophages. We hypothesize that increased NQO1 expression may reflect an endogenous defense response against ROS-mediated cellular toxicity. Compounds that induce the production of endogenous antioxidant enzymes, such as NQO1, may be potential targets for future treatment strategies in MS.

Rochester L, Hetherington V, Jones D, Nieuwboer A, Willems AM, Kwakkel G, Van Wegen E. The effect of external rhythmic cues (auditory and visual) on walking during a functional task in homes of people with Parkinson's disease. Objectives To evaluate (1) the influence of rhythmic cues on gait interference during a functional activity and (2) the relationship of clinical symptoms to gait interference. Design Repeated-measures study. Setting Participants' homes. Participants Twenty subjects with idiopathic Parkinson's disease (PD) and a control group of 10 age-, sex-, and education-matched subjects. Interventions Subjects performed a simple functional task that included a walking component and a dual-motor task. The functional task was performed with and without external rhythmic (auditory and visual) cues. Main outcome measures Walking speed, mean step length, and step frequency were compared during trials of the tasks. In addition, tests of cognitive executive function (Hayling and Brixton tests), anxiety and depression (Hospital Anxiety and Depression Scale), and fatigue (Multidimensional Fatigue Inventory) were undertaken. Results The use of auditory cues during a dual task involving gait reduced the interference effect on the task; significant increases in step length were observed in PD subjects ( P =.018), representing an increase of 19%. Conclusions External auditory cues may be useful in reducing interference and maintaining gait performance during more complicated functional activities. Clinical symptoms, such as depression and fatigue, could influence the ability to focus attention and may increase gait interference during the performance of complex tasks, with subsequent implications for functional walking and safety.

In active multiple sclerosis (MS) lesions macrophages expressing myeloid related protein (MRP) 8/14 are present. The aim of this study was to determine whether serum levels of MRP8/14 complexes are related to disease activity in MS. In a longitudinal study of 16 relapsing remitting (RR) MS patients that underwent monthly gadolinium diethylentriaminepenta acid (Gd-DTPA) magnetic resonance imaging (MRI), the relation between serum MRP8/14 levels and disease activity was investigated. Patients were participating in a monoclonal antibody study targeting a specific T cell population (Vbeta5.2/5.3+ T-cells). In time, within patients large variations in serum MRP8/14 levels were observed. Serum MRP8/14 levels were not related to changes in clinical disease activity or increase in Gd-DTPA lesion enhancement. Neither did comparison of active (>1 relapse in follow-up period) with inactive (0-1 relapse) MS patients reveal any differences in MRP8/14 levels. Therefore, we conclude that although MRP8/14 expression is a good histopathological marker for monocyte activation, serum levels of these proteins do not correlate with disease activity in RR MS.

We have investigated the role of p75NTR in inflammation in experimental allergic encephalomyelitis (EAE), a model for the human disease multiple sclerosis (MS). Induction of EAE in C57/BL6 wild-type mice resulted in expression of p75NTR in endothelial cells in the CNS. In contrast to the clinical manifestation of EAE observed in wild-type C57/BL6 mice, mice deficient for p75NTR (p75NTR knockout mice) developed severe or lethal disease and concomitant increased levels of inflammation in the CNS. Our findings suggest a physiological significant role for p75NTR in CNS endothelial cells during inflammation and involvement in preservation of blood-brain barrier integrity during a severe infiltrative attack.

Background. We investigated the effects of different intensities of arm and leg rehabilitation training on the functional recovery of activities of daily living (ADL), walking ability, and dexterity of the paretic arm, in a single-blind randomised controlled trial. Methods. Within 14 days after stroke onset, 101 severely disabled patients with a primary middle-cerebral-artery stroke were randomly assigned to: a rehabilitation programme with emphasis on arm training; a rehabilitation programme with emphasis on leg training; or a control programme in which the arm and leg were immobilised with an inflatable pressure splint. Each treatment regimen was applied for 30 min, 5 days a week during the first 20 weeks after stroke. In addition, all patients underwent a basic rehabilitation programme. The main outcome measures were ability in ADL (Barthel index), walking ability (functional ambulation categories), and dexterity of the paretic arm (Action Research aim test) at 6, 12, 20, and 26 weeks. Analyses were by intention to treat. Findings. At week 20, the leg-training group (n = 31) had higher scores than the control group (n = 37) for ADL ability (median 19 [IQR 16-20] vs 16 [10-19], p < 0.05)], walking ability (4 [3-5] vs 3 [1-4], p < 0.05), and dexterity (2 [0-56] vs 0 [0-2], p < 0.01). The arm-training group (n = 33) differed significantly from the control group only in dexterity (9 [0-39] vs 0 [0-2], p < 0.01). There were no significant differences in these endpoints at 20 weeks between the arm-training and leg training groups. Interpretation. Greater intensity of leg rehabilitation improves functional recovery and health-related functional status, whereas greater intensity of arm rehabilitation results in small improvements in dexterity, providing further evidence that exercise therapy primarily induces treatment effects on the abilities at which training is specifically aimed.

Contains fulltext : 51317.pdf (Publisher’s version ) (Closed access) PURPOSE: The present debate paper addresses four relevant issues related to the impact of intensity of practice after stroke. First, the best way to define intensity of practice is discussed. Second, the paper describes the evidence that exists for a dose-response relationship in stroke rehabilitation. Third, the relevance of an appropriate patient selection for a meaningful intensive practice is explored. Finally, the paper raises the question of what it is that patients actually learn when they improve their functional skills.Search strategy. For this purpose articles from MEDLINE, CINAHL, Cochrane Central Register of Controlled Trials, PEDro, DARE and PiCarta and references presented in relevant publications were examined. DISCUSSION AND CONCLUSION: Although, there is strong evidence that early augmented exercise therapy time (expressed as time dedicated to practice) may enhance functional recovery, there is a discrepancy between the evidence for the benefits of intensive practice, on the one hand, and, the implementation of intensive rehabilitation treatment programmes in the current healthcare system on the other. Further emphasis should be given on a better understanding of the time-dependency of prognostic factors that determine the effectiveness of intensive practice in patients with stroke. In addition, a better understanding is needed of the neurophysiological and biomechanical mechanisms that underlie compensation-related learning of functional tasks after stroke.