Search

Tractography has become a widely available tool for the planning of neurosurgical operations as well as for neuroscientific research. The absence of patient interaction makes it easily applicable. However, it leaves uncertainty about the functional relevance of the identified bundles. We retrospectively analyzed the correlation of white matter markers with their clinical function in 24 right-handed patients who underwent first surgery for high-grade glioma. Morphological affection of the corticospinal tract (CST) and grade of paresis were assessed before surgery. Tractography was performed manually with MRTrix3 and automatically with TractSeg. Median and mean fractional anisotropy (FA) from manual tractography showed a significant correlation with CST affection (p = 0.008) and paresis (p = 0.015, p = 0.026). CST affection correlated further most with energy, and surface-volume ratio (p = 0.014) from radiomic analysis. Paresis correlated most with maximum 2D column diameter (p = 0.005), minor axis length (p = 0.006), and kurtosis (p = 0.008) from radiomic analysis. Streamline count yielded no significant correlations. In conclusion, mean or median FA can be used for the assessment of CST integrity in high-grade glioma. Also, several radiomic parameters are suited to describe tract integrity and may be used to quantitatively analyze white matter in the future., (© 2024. The Author(s).)

Balance and functional impairment could occur due to the weakness of the gastrocsoleus muscles in acute stroke patients. This study was planned to determine the muscle architecture and its relationship to balance and functional strength functional ability in patients with acute stroke. A cross-sectional analysis of 22 stroke patients (68.59 ± 8.16) was performed in this study. Gastrocnemius muscle thickness and cross-sectional area were significantly greater on the non-paretic than on the paretic sides ( p  = 0.004, p  = 0.005, respectively). Partial correlation analysis showed that soleus muscle thickness and cross-sectional area was significantly correlated with Berg Balance Scale, Single Leg Stance Test, Five Times Sit to Stand Test and Tandem test results in the paretic side ( r  = 0.49-0.77, p  < 0.05). The gastrocnemius muscle thickness of the non-paretic side had a significant relationship with balance ( r  = 0.45-0.65, p  < 0.05). The muscle thickness and cross-sectional area of the soleus muscle on the paretic sides was significantly related with the functional strength and balance after stroke. It may be beneficial to develop clinical assessment and intervention programs focusing on distal plantar flexor muscle groups in order to improve the functional status and balance.

Background: We report a patient with a novel c.737 C > T variant (p.Ser246Leu) of the TPM3 gene presenting with adult-onset distal myopathy., Case Presentation: A 35-year-old Chinese male patient presented with a history of progressive finger weakness. Physical examination revealed differential finger extension weakness, together with predominant finger abduction, elbow flexion, ankle dorsiflexion and toe extension weakness. Muscle MRI showed disproportionate fatty infiltration of the glutei, sartorius and extensor digitorum longus muscles without significant wasting. Muscle biopsy and ultrastructural examination showed a non-specific myopathic pattern without nemaline or cap inclusions. Genetic sequencing revealed a novel heterozygous p.Ser246Leu variant (c.737C>T) of the TPM3 gene which is predicted to be pathogenic. This variant is located in the area of the TPM3 gene where the protein product interacts with actin at position Asp25 of actin. Mutations of TPM3 in these loci have been shown to alter the sensitivity of thin filaments to the influx of calcium ions., Conclusion: This report further expands the phenotypic spectrum of myopathies associated with TPM3 mutations, as mutations in TPM3 had not previously been reported with adult-onset distal myopathy. We also discuss the interpretation of variants of unknown significance in patients with TPM3 mutations and summarise the typical muscle MRI findings of patients with TPM3 mutations., (© 2023. The Author(s).)

Dyk-Davidoff-Masson Syndrome (DDMS) is one of the rare neurological conditions attributed to the development of drug-resistant epilepsy (DRE). The DDMS condition is characterized by cerebral hemisphere asymmetry, where atrophy occurs on one side of the brain and clinically manifests as hemiparesis, seizure disorder, mental retardation, and facial asymmetry. In addition, the condition has various perinatal or postnatal etiologies. Herein, we report the case of a 29-year-old right-handed male with Dyke-Davidoff Masson syndrome and mild right-side weakness. The patient experiences attacks of seizures with stiffness in his right arm and right leg, sometimes experiencing agitation and abnormal movement of the body parts. The MRI of the brain showed asymmetry with atrophic changes involving the left hippocampus, consisting of mesial temporal sclerosis. Additionally, the results showed the presence of gyral hyperintensities over the left parietal region. Therefore, the patient's case is reported with a literature review to support it., (Copyright: © Neurosciences.)

Competing Interests: Competing interests: The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: none. Further details of The BMJ policy on financial interests are here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests.

The Aim of the Study: Was the increasing the effectiveness of treatment and prevention of postoperative complications in the patients with benign tumors of the parotid salivary gland through the combined use of medications, acupuncture, hirudotherapy and a complex of physiotherapy., Materials and Methods: The study comprised 94 patients with postoperative complications after surgical treatment of benign tumors of the parotid salivary gland. All patients suffering from paresis of facial muscles were prescribed a physiotherapy complex developed during the study consisting of two series of exercises with alternating execution of the series every other day. The exercises begin with the upper third of the face, gradually descending to the lower third. A series of exercises is performed every hour and a half, the session duration is twenty minutes, the course is 14 days. The exercises are performed by the patient in front of the mirror, gently and at a slow pace., Results: The duration of the recovery period of motor function of the facial muscles on the affected side was 31.2±19.6 days, with the amplitude of the M-response 1.45±0.28 mV, the duration of the M-response 8.04±0.27 ms and the latent time during EMG 3.18±0.86 ms. Conclusion. The combined treatment, which included surgical and conservative treatment complex with methods of acupuncture, hirudotherapy and physiotherapy, was significantly more effective ( p <0.05) in terms of the severity of paresis of facial muscles than in the control group.

A muscle's structure, or architecture, is indicative of its function and is plastic; changes in input to or use of the muscle alter its architecture. Stroke-induced neural deficits substantially alter both input to and usage of individual muscles. We combined in vivo imaging methods (second-harmonic generation microendoscopy, extended field-of-view ultrasound, and fat-suppression MRI) to quantify functionally meaningful architecture parameters in the biceps brachii of both limbs of individuals with chronic hemiparetic stroke and in age-matched, unimpaired controls. Specifically, serial sarcomere number (SSN) and physiological cross-sectional area (PCSA) were calculated from data collected at three anatomical scales: sarcomere length, fascicle length, and muscle volume. The interlimb differences in SSN and PCSA were significantly larger for stroke participants than for participants without stroke ( P = 0.0126 and P = 0.0042, respectively), suggesting we observed muscle adaptations associated with stroke rather than natural interlimb variability. The paretic biceps brachii had ∼8,200 fewer serial sarcomeres and ∼2 cm 2 smaller PCSA on average than the contralateral limb (both P < 0.0001). This was manifested by substantially smaller muscle volumes (112 versus 163 cm 3 ), significantly shorter fascicles (11.0 versus 14.0 cm; P < 0.0001), and comparable sarcomere lengths (3.55 versus 3.59 μm; P = 0.6151) between limbs. Most notably, this study provides direct evidence of the loss of serial sarcomeres in human muscle observed in a population with neural impairments that lead to disuse and chronically place the affected muscle at a shortened position. This adaptation is consistent with functional consequences (increased passive resistance to elbow extension) that would amplify already problematic, neurally driven motor impairments., Competing Interests: The authors declare no competing interest.

Background: Knowledge of the deficits underlying handgrip performance is fundamental for the development of targeted interventions., Objectives: The purpose of this study was to evaluate maximal handgrip strength, fatigue resistance, grip work, and muscle fatigue in mildly affected stroke persons., Methods: We conducted a prospective observational study. A total of 20 individuals after a first unilateral ischemic/hemorrhagic chronic stroke (months poststroke: mean 33.64 ± 19.60), mildly affected according to functional score (FIM: 112.71 ± 16.14) and with arm motor impairment (upper-extremity Fugl-Meyer score: mean 57.07 ± 7.82 on the contralesional side); and 20 sex and age-matched controls were included. The outcomes assessed were maximal handgrip strength evaluated through maximal voluntary contraction, fatigue resistance defined as the seconds during which grip strength dropped to 50% of its maximum and gripwork, which was calculated using the equation grip work = maximal grip strength * 0.75 * fatigue resistance. Muscle fatigue was assessed using surface electromyography during a sustained contraction over 50% of maximal voluntary contraction., Results: Persons with stroke demonstrated significantly reduced handgrip performance regarding maximal handgrip strength, resistance to fatigue, grip work, and muscle fatigue for the contralesional hand. In addition, a reduced grip resistance and muscle fatigue was shown for the ipsilesional hand compared with controls. We found no effect of the hemispheric side of the lesion on the grip performance measures assessed., Conclusions: Our findings provide evidence that handgrip performance remain impaired after 6 months after stroke, and may serve as a target for interventions to improve these abilities after stroke.

The aim of our study was to validate the method of head-shake static posturography (HS-posturography) in healthy individuals and to establish the value of this novel method in the diagnostics of patients with unilateral vestibular lesion (UV). The study included 202 participants divided into two groups, one consisting of 133 patients with canal paresis CP > 19% and one of 69 healthy subjects. Participant was tested according to the standard protocol of static posturography (SP), and with head movements of 0.3 Hz (HS 40), 0.6 Hz (HS 70) in random order controlled by a metronome. HS-posturography revealed a similar repeatability and internal consistency as the standard posturography. In patients with UV, 4th condition revealed higher sensitivity (74%) and specificity (71%) in HS 40 than in the standard posturography (67%, 65% respectively) and HS 70 (54%, 70% respectively). Static posturography and HS- posturography revealed a high reliability of the testing method. The head movements added to static posturography improve the sensitivity and specificity of the method in group with vestibular impairment. The most important test for that purpose seems to be the one on unstable surface with the eyes closed, with low frequency of head movements.

Elongator is a multi-subunit protein complex bearing six different protein subunits, Elp1 to -6, that are highly conserved among eukaryotes. Elp2 is the second major subunit of Elongator and, together with Elp1 and Elp3, form the catalytic core of this essential complex. Pathogenic variants that affect the structure and function of the Elongator complex may cause neurodevelopmental disorders. Here, we report on a new family with three children affected with a severe form of intellectual disability along with spastic tetraparesis, choreoathetosis, and self injury. Molecular genetic analyses reveal a homozygous missense variant in the ELP2 gene (NM&#95;018255.4 (ELP2): c.1385G > A (p.Arg462Gln)), while in silico studies suggest a loss of electrostatic interactions that may contribute to the overall stability of the encoded protein. We also include a comparison of the patients with ELP2-related neurodevelopmental disorder to those previously reported in the literature. Apart from being affected with intellectual disability, we have extremely limited clinical knowledge about patients harboring ELP2 variants. Besides providing support to the causal role of p.Arg462Gln in ELP2-related neurodevelopmental disorder, we add self-injurious behavior to the clinical phenotypic repertoire of the disease.

Background : Stroke-related falls occur at especially high rates in rehabilitation settings. Inpatient-hospital falls have been identified as one of the most common medical complications after stroke, negatively influencing recovery, nevertheless, the role of cognition in relation to falls during inpatient rehabilitation is largely unexplored. Objective . We aim to predict inpatient falls in a subacute stroke rehabilitation setting using previously reported variables such as stroke severity, gender, age, ataxia, hemiparesis, and functionality in activities of daily living, further extending them with specific cognition variables assessing memory, verbal fluency, attention, and orientation. Methods : This observational study included 158 stroke patients admitted to a rehabilitation center between 2007 and 2019, with less than 30 days since stroke onset to admission. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS). Four logistic regressions were performed including NIHSS, age, sex, ataxia, and hemiparesis plus one of the following: (1) Functional Independence Measure cognitive (C-FIM) and motor (M-FIM) subtests. (2) individual C-FIM items, (3) Ray Auditory Verbal Memory Test (RAVLT) and (4) verbal fluency test (PMR), Digit Span from Wechsler Adult Intelligence Scale (WAIS III), and Orientation from Test Barcelona. Results : Neither NIHSS, age, sex, ataxia nor hemiparesis predicted falls. C-FIM was a significant predictor (AUC:0.891), but not M-FIM. The problem solving C-FIM item (AUC:0.836), the RAVLT learning subtest (AUC:0.879), and PMR verbal fluency (AUC:0.871) were significant predictors for each model, respectively. Conclusions : Cognition assessments, i.e., one FIM item, one RAVLT item, or a one-minute verbal fluency test are significant falls predictors.

We report here a case of a 17-year-old boy with viral encephalitis associated with human parvovirus B19 who presented consciousness disturbance, left hemiparesis, and focal neurologic signs. The diagnosis was based on the specific sequence reads corresponding to human parvovirus B19 (PVB19) in a CSF sample as analyzed by metagenomic next-generation sequencing (mNGS). Thus, PVB19 should be considered in the differential diagnosis of encephalitis and encephalopathy of unknown etiology. The introduction of mNGS into the diagnostic protocol of neuropathies, especially for those undiagnosed, could interrogate all genetic information in a biologic sample and facilitate the identification of the etiological agent.

Sinking skin flap syndrome is a craniectomy complication characterized by new neurological dysfunction that typically worsens in the upright position and improves after cranioplasty. We present a 33-year-old man who experienced hemiparesis in the upright position after craniectomy. Upright computed tomography (CT) before cranioplasty showed a remarkable shift of the brain compared to supine CT. After cranioplasty, both symptoms and brain shift on CT resolved. Upright CT enables detection and objective evaluation of paradoxical herniation and midline shift that is not obvious on supine imaging modalities. Clinicians need to be aware of positional brain shift in postcraniectomy patients.

Background: Anomalies of pyramidal tract decussation are rare phenomena that can be caused by ectodermal dysplasia. Herein, we describe a patient with ichthyosis who exhibited ipsilateral hemiparesis after stroke and whose neuroimaging results showed evidence of motor control being provided by the ipsilateral motor cortex., Case Presentation: A 24-year-old right-handed man presented with skin abnormalities, sudden-onset left hemiparesis, and dysarthria. He exhibited a mild-to-moderate left-sided weakness (grade 4 on the Medical Research Council scale). Magnetic resonance imaging revealed an acute infarct in the left corona radiata. Diffusion tensor imaging revealed uncrossed corticospinal tracts. Next-generation sequencing identified heterozygous FLG mutations. The patient was diagnosed with cerebral infarction and ichthyosis vulgaris and was treated with aspirin (100 mg/d). His symptoms gradually dissipated., Conclusions: This case suggests that pyramidal decussation anomalies can be associated with ichthyosis. Patients with ichthyosis should therefore be evaluated for nerve involvement.

Background: To evaluate the presence of Wallerian degeneration and its relationship with sensorimotor deficits following childhood-onset arterial ischemic stroke (AIS)., Methods: Children surviving unilateral AIS older than one month of age were assessed for severity of sensorimotor neurological deficit with the Pediatric Stroke Outcome Measure at least one year post stroke (mean follow-up = 2.9 years, S.D. = ±1.6). The area (mm 3 ) of each cerebral peduncle was measured on T2-weighted magnetic resonance images to calculate an Asymmetry Index (AI). The AI between patients with childhood stroke (cases) and controls (children with normal MRI) was compared. In the stroke group, the AI between patients with good and poor motor outcome, and the correlation between the AI and motor outcome was calculated., Results: Asymmetry was compared in 52 children with stroke (cases) and 20 controls (normal brain MRIs). The AI was greater in patients with stroke (mean = 6.8%, S.D. = ±5.9) compared with controls (mean = 3.4%, S.D. = ±3.5, P < 0.02). Patients with poor outcome had an AI of 10% or greater compared with patients with good outcome (mean 10.4 versus 4, P < 0.001), and the AI was moderately correlated with motor deficit severity (r = 0.582, P = 0.001)., Conclusions: Asymmetry of the cerebral peduncle is a feasible method of assessing Wallerian degeneration in children with unilateral AIS. The degree of asymmetry in the cerebral peduncles was moderately correlated with neurological outcome severity and reflects the degree of motor deficit in children following stroke., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background. Previous research has detailed the hemisphere dependence and specific kinematic deficits observed for the less-affected arm of patients with unilateral stroke. Objective. We now examine whether functional motor deficits in the less-affected arm, measured by standardized clinical measures of motor function, also depend on the hemisphere that was damaged and on the severity of contralesional impairment. Methods. We recruited 48 left-hemisphere-damaged (LHD) participants, 62 right-hemisphere-damaged participants, and 54 age-matched control participants. Measures of motor function included the following: (1) Jebsen-Taylor Hand Function Test (JHFT), (2) Grooved Pegboard Test (GPT), and (3) grip strength. We measured the extent of contralesional arm impairment with the upper-extremity component of the Fugl-Meyer (UEFM) assessment of motor impairment. Results. Ipsilesional limb functional performance deficits (JHFT) varied with both the damaged hemisphere and severity of contralesional arm impairment, with the most severe deficits expressed in LHD participants with severe contralesional impairment (UEFM). GPT and grip strength varied with severity of contralesional impairment but not with hemisphere. Conclusions. Stroke survivors with the most severe paretic arm impairment, who must rely on their ipsilesional arm for performing daily activities, have the greatest motor deficit in the less-affected arm. We recommend remediation of this arm to improve functional independence in this group of stroke patients.

Damage to the corticospinal tract is widely studied following unilateral subcortical stroke, whereas less is known about changes to other sensorimotor pathways. This may be due to the fact that many studies investigated morphological changes in the brain, where the majority of descending and ascending brain pathways are overlapping, and did not investigate the brainstem where they separate. Moreover, these pathways continue passing through separate regions in the spinal cord. Here, using a high-resolution structural MRI of both the brainstem and the cervical spinal cord, we were able to identify a number of microstructurally altered pathways, in addition to the corticospinal tract, post stroke. Moreover, decreases in ipsi-lesional corticospinal tract integrity and increases in contra-lesional medial reticulospinal tract integrity were correlated with motor impairment severity in individuals with stroke.

Regulation of whole-body angular momentum (WBAM) is essential for maintaining dynamic balance during gait. Patients with hemiparesis frequently fall toward the anterior direction; however, whether this is due to impaired WBAM control in the sagittal plane during gait remains unknown. The present study aimed to investigate the differences in WBAM in the sagittal plane during gait between patients with hemiparesis and healthy individuals. Thirty-three chronic stroke patients with hemiparesis and twenty-two age- and gender-matched healthy controls walked along a 7-m walkway while gait data were recorded using a motion analysis system and force plates. WBAM and joint moment were calculated in the sagittal plane during each gait cycle. The range of WBAM in the sagittal plane in the second half of the paretic gait cycle was significantly larger than that in the first and second halves of the right gait cycle in the controls (P = 0.015 and P = 0.011). Furthermore, multiple regression analysis revealed the slower walking speed (P < 0.001) and larger knee extension moment on the non-paretic side (P = 0.003) contributed to the larger range of WBAM in the sagittal plane in the second half of the paretic gait cycle. Our findings suggest that dynamic stability in the sagittal plane is impaired in the second half of the paretic gait cycle. In addition, the large knee extension moment on the non-paretic side might play a role in the dynamic instability in the sagittal plane during gait in patients with hemiparesis., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: In the list of named numerical neuro-ophthalmological syndromes, such as one-and-a-half syndrome and others, we report for the first time twenty-and-a-half syndrome, which is characterized by one-and-a-half syndrome with bilateral seventh and right fifth nerve palsy (1.5 + 7 + 7 + 5 = 20.5) in a patient with ischemic stroke., Case Presentation: A 45-year-old Asian Hindu woman presented with vomiting and imbalance of 1 day's duration. She had left-sided ataxic hemiparesis with one-and-a-half syndrome with bilateral seventh and right fifth nerve palsy. Magnetic resonance imaging of her brain revealed acute non-hemorrhagic infarct in the right posterolateral aspect of pons and medulla, with normal brain vessels angiography. We described her disorder as twenty-and-a-half syndrome. She was put on antiplatelet therapy., Conclusions: Twenty-and-a-half syndrome is reported for the first time. It is due to posterior circulation stroke; in our case, it was due to lacunar infarcts in the pons and medulla, manifesting as one-and-a-half syndrome with bilateral seventh and right fifth nerve palsy.

The connections between large neuronal networks were analyzed in 12 patients with ischemic or hemorrhagic strokes and hemiparesis included in the course of the interactive brain stimulation in the area of the primary motor cortex by the analysis of independent components of fMRI. The results obtained in 3 patients are presented. Desynchronization of the visual networks with each other and with the motor networks as well as positive dynamics in Rankin scale and box and blocks test were observed in the patients. These data attest to a decrease in the importance of visual control during movements and probably on partial restoration of prioperception. The important role of interactive brain stimulation and network analysis of fMRI data in neurology are discussed.

We sought to determine the relative velocity sensitivity of stretch reflex threshold angle and reflex stiffness during stretches of the paretic elbow joint in individuals with chronic hemiparetic stroke, and to provide guidelines to streamline spasticity assessments. We applied ramp-and-hold elbow extension perturbations ranging from 15 to 150°/s over the full range of motion in 13 individuals with hemiparesis. After accounting for the effects of passive mechanical resistance, we modeled velocity-dependent reflex threshold angle and torque-angle slope to determine their correlation with overall resistance to movement. Reflex stiffness exhibited substantially greater velocity sensitivity than threshold angle, accounting for ~ 74% (vs. ~ 15%) of the overall velocity-dependent increases in movement resistance. Reflex stiffness is a sensitive descriptor of the overall velocity-dependence of movement resistance in spasticity. Clinical spasticity assessments can be streamlined using torque-angle slope, a measure of reflex stiffness, as their primary outcome measure, particularly at stretch velocities greater than 100°/s.

Our aim was to measure the venous blood flow velocity (VBFV) in case of hemiparetic patients, after passive and active thromboembolic methods, as well as the consensual effect in the hemiparetic limb following the active venous exercises in the healthy limb. We examined 215 patients, with the median age of 58.0 (55.0-63.0) years. The VBFV was measured with a HADECO BIDOP ES-100 V II type Doppler ultrasound device, using an 8 MHz head, on the femoral vein at the level of the hip joint. For statistical analysis, SPSS version 22 was used. After passive movement, on the hemiparetic side, compared to the value in resting state, the VBFV significantly (12.6; 11.6-13.5 cm/s; P < .001) increased. Following active venous exercises performed on the healthy side, the VBFV significantly (18.0; 15.6-19.6 cm/s; P < .001) increased compared to the value in resting state. Following the active venous exercises performed on the healthy side, the VBFV measured on the hemiparetic side (consensual effect) was significantly (15.1 [14.1-16.5] cm/s; P < .001) higher than the value on the hemiparetic side in resting state. Active and passive mechanical thromboprophylaxis methods can be effective. Movements of the healthy limb significantly increase the VBFV in the inactive limb, and patients can perform it themselves several times a day.

Objectives: The ability of voxel-based lesion-symptom mapping (VLSM) to define the functional anatomy of the human brain has not been fully assessed. With a view to assessing VLSM's validity, the present study analyzed the technique's ability to determine the known clinical-anatomic correlates of hemiparesis in stroke patients., Design: Lesions (damaged in at least 5 patients) associated with transformed limb motor score (after adjustment on lesion volume) at 6 months were examined in 272 patients using VLSM. The value of additional multivariable linear, logistic and Bayesian analyses was examined., Results: We first checked that motor hemiparesis was fully accounted for by corticospinal tract (CST) lesions (sensitivity = 100%; p = 0.0001). Conventional VLSM analysis flagged up 2 regions corresponding to the CST, but also 8 regions located outside the CST. All 10 brain regions achieving statistical significance in the VLSM analysis were submitted to 3 additional analyses. The backward linear regression analysis selected 5 regions, one only corresponding to the CST (R 2 : 0.03, p = 0.0008). The logistic regression analysis selected correctly the CST (OR: 2.39, 95%CI: 1.44-3.96; 0.001). The Bayesian network analysis selected regions including the CST (in 92% of 3000 bootstrap replications) and identified the source of multicollinearity. These lesions evaluated by structural equation modeling resulted in an excellent fit (p-value = 0.228, chi/df = 1.19, RMSEA = 0.032, CFI = 0.999). Analyses of confusion factors showed that conventional VLSM analyses were strongly influenced by lesion frequency (R 2 = 0.377; p = 0.0001) and multicollinearity., Conclusions: Conventional VLSM analyses are sensitive but weakened by a type I error due to the combined effects of multicollinearity and lesion frequency. We demonstrate that the addition of a Bayesian network analysis, and to a lesser extent of logistic regression, controlled for this type I error and constituted a reliable means of defining the functional anatomy of the motor system in stroke patients., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Research investigating action observation-execution priming has mainly manipulated congruent versus incongruent action, and aspects of action expertise/capability. More specifically, the literature suggests enhanced performance priming following action observation by actors closely matched to participant expertise. The aim of the present study was to extend the understanding of action expertise effects by investigating action priming in healthy participants after observing a mild hemiparetic child actor versus a neurologically healthy child actor., Methods: 16 healthy right-handed children, aged 6-13 years were tested. Several motor assessments were performed, including gross and fine manual motor ability, and upper limb kinematics measured using a precise robotic device. A cross-over design consisted in two experimental conditions (observing actions performed by a child with hemiparesis versus observing actions performed by a healthy child) and a pre-observation double baseline control condition, with the data analyzed using repeated measures ANOVA., Results: Relative to baseline, both types of action observation conditions enhanced fine manual dexterity, but observing the hemiparetic child enhanced gross manual dexterity and upper limb velocity kinematics relative to observing actions performed by a healthy child. No effects were shown on measures of smoothness and accuracy., Discussion: Contradictorily to hypotheses discussed in the literature, results here showed evidence of enhanced action execution when healthy children observed hemiparetic compared to healthy child actions. These results are discussed in terms of how patient compared to healthy actors may be useful for clinical action observation priming therapy., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: Improving muscle mass and intramuscular fat in the mid-thigh increases the muscle strength of the paretic and non-paretic limbs in ambulatory chronic stroke survivors. There is a remarkable decrease in muscle mass and muscle strength and an increase in intramuscular fat in the quadriceps of both limbs of non-ambulatory compared with ambulatory survivors. Therefore, given that paretic lower extremity function does not recover sufficiently in the chronic phase, it may be helpful to improve muscle mass and intramuscular fat to increase muscle strength in the quadriceps of non-ambulatory chronic stroke survivors. However, these relationships remain unclear. The purpose of this study was to clarify the relationships between muscle strength, muscle mass, and intramuscular fat of the quadriceps in non-ambulatory chronic stroke survivors., Methods: Study design: A cross-sectional study. Participants: Fifty non-ambulatory chronic stroke survivors. Main outcome measures: Quadriceps muscle strength was measured using a handheld dynamometer. Transverse ultrasound images were acquired using B-mode ultrasound imaging. Muscle mass and intramuscular fat of the quadriceps were assessed based on muscle thickness and echo intensity, respectively. Data analysis: Stepwise multiple regression analyses were used to identify the factors independently associated with the quadriceps muscle strength of the paretic and non-paretic limbs. To avoid multicollinearity, muscle thickness and echo intensity were entered into separate multiple regression models. Muscle thickness or echo intensity of the paretic or non-paretic limbs and other confounding factors were set as the independent variables., Results: Muscle thickness was positively related and echo intensity was negatively related to the quadriceps muscle strength of the paretic and non-paretic limbs., Conclusions: Muscle mass and intramuscular fat of the quadriceps are related to muscle strength in non-ambulatory chronic stroke survivors. Increasing muscle mass and decreasing intramuscular fat of the quadriceps of both limbs may improve muscle strength., Competing Interests: The authors have declared that no competing interests exist.

Disorganization of nodes of Ranvier is associated with motor and sensory dysfunctions. Mechanisms that allow nodal recovery during pathological processes remain poorly understood. A highly enriched nodal cytoskeletal protein βIV spectrin anchors and stabilizes the nodal complex to actin cytoskeleton. Loss of murine βIV spectrin allows the initial nodal organization, but causes gradual nodal destabilization. Mutations in human βIV spectrin cause auditory neuropathy and impairment in motor coordination. Similar phenotypes are caused by nodal disruption due to demyelination. Here we report on the precise timelines of nodal disorganization and reorganization by following disassembly and reassembly of key nodal proteins in βIV spectrin mice of both sexes before and after βIV spectrin re-expression at specifically chosen developmental time points. We show that the timeline of nodal restoration has different outcomes in the PNS and CNS with respect to nodal reassembly and functional restoration. In the PNS, restoration of nodes occurs within 1 month regardless of the time of βIV spectrin re-expression. In contrast, the CNS nodal reorganization and functional restoration occurs within a critical time window; after that, nodal reorganization diminishes, leading to less efficient motor recovery. We demonstrate that timely restoration of nodes can improve both the functional properties and the ultrastructure of myelinated fibers affected by long-term nodal disorganization. Our studies, which indicate a critical timeline for nodal restoration together with overall motor performance and prolonged life span, further support the idea that nodal restoration is more beneficial if initiated before any axonal damage, which is critically relevant to demyelinating disorders. SIGNIFICANCE STATEMENT Nodes of Ranvier are integral to efficient and rapid signal transmission along myelinated fibers. Various demyelinating disorders are characterized by destabilization of the nodal molecular complex, accompanied by severe reduction in nerve conduction and the onset of motor and sensory dysfunctions. This study is the first to report in vivo reassembly of destabilized nodes with sequential improvement in overall motor performance. Our study reveals that nodal restoration is achievable before any axonal damage, and that long-term nodal destabilization causes irreversible axonal structural changes that prevent functional restoration. Our studies provide significant insights into timely restoration of nodal domains as a potential therapeutic approach in treatment of demyelinating disorders., (Copyright © 2018 the authors 0270-6474/18/386267-16$15.00/0.)

Dyke Davidoff- Masson syndrome is a rare disorder of hemiatrophy of the cerebral hemisphere and clinically manifests as hemiparesis, seizures disorder, mental retardation and facial asymmetry and has various perinatal or post natal etiologies and has characteristic radiological appearance on brain imaging. It is important to recognize the clinical and radiological features of this condition for the neurologists as well as the radiologists. We are discussing our case as this patient presented very late although his symptoms seem to present since his birth which is very unusual with this disorder.

We report a case of a 20-month-old girl with atypical presentation of a fairly common condition. She presented with acute onset of fever, seizures, and hemiparesis. Her cerebrospinal fluid showed total nucleated cells 10/mm 3 with lymphocyte dominance. Polymerase chain reaction was negative for herpes simplex virus. Computed tomography of head showed a cerebral hemorrhage of the left frontal lobe and small subarachnoid hemorrhage in the right frontal region. Brain magnetic resonance imaging revealed multiple foci of hyperintensity in bilateral parietal lobes and right basal ganglia. She remained clinically stable without a specific therapy. Her diagnosis was made after a brain biopsy., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose : The study main aim was to compare the cross-sectional area (CSA) and thickness of the plantar muscles and fascia in the hemiparesis and contralateral feet of poststroke survivors with respect to healthy feet of matched controls. Methods : A case-control observational study was performed using B-mode rehabilitative ultrasound imaging. A convenience sampling method was used to select 60 feet. The sample was divided into 20 feet ipsilateral and 20 feet contralateral to the hemiparesis lower limb from poststroke survivors, as well as 20 healthy feet from matched controls. The CSA and thickness of the abductor hallucis, flexor digitorum brevis and flexor hallucis brevis, as well as the thickness for the posterior, middle and anterior plantar fascia portions were measured. Comparisons and multivariate predictive analyses were carried out for ultrasound measurements. In all analyses, a P -value<.01 with a 99% confidence interval was considered as statistically significant. Results : Statistically significant differences ( P <.01) were shown for a flexor hallucis brevis thickness increase as well as middle and anterior plantar fascia thickness decrease of the hemiparesis feet and contralateral feet with respect to the healthy matched control feet. The rest of measurements did not show any statistically significant difference ( P >.01). Conclusions : The thickness of the flexor hallucis brevis muscle as well as the middle and anterior plantar fascia portions of the hemiparesis and contralateral feet from poststroke survivors presented morphology changes with respect to the healthy matched control feet., Competing Interests: Conflicts of interest: All authors have no conflicts of interest to report. All of the authors of the manuscript received any remuneration. Further, the authors have not received any reimbursement or honorarium in any other manner. The authors are not affiliated in any manner.

Key Points: Activation of the shoulder abductor muscles in the arm opposite a unilateral brain injury causes involuntary increases in elbow, wrist and finger flexion in the same arm, a phenomenon referred to as the flexion synergy. It has been proposed that flexion synergy expression is related to reduced output from ipsilesional motor cortex and corticospinal pathways. In this human subjects study, we provide evidence that the magnitude of flexion synergy expression is instead related to a progressive, task-dependent recruitment of contralesional cortex. We also provide evidence that recruitment of contralesional cortex may induce excessive activation of ipsilateral reticulospinal descending motor pathways that cannot produce discrete movements, leading to flexion synergy expression. We interpret these findings as an adaptive strategy that preserves low-level motor control at the cost of fine motor control., Abstract: A hallmark of hemiparetic stroke is the loss of fine motor control in the contralesional arm and hand and the constraint to a grouped movement pattern known as the flexion synergy. In the flexion synergy, increasing shoulder abductor activation drives progressive, involuntary increases in elbow, wrist and finger flexion. The neural mechanisms underlying this phenomenon remain unclear. Here, across 25 adults with moderate to severe hemiparesis following chronic stroke and 18 adults without neurological injury, we test the overall hypothesis that two inter-related mechanisms are necessary for flexion synergy expression: increased task-dependent activation of the intact, contralesional cortex and recruitment of contralesional motor pathways via ipsilateral reticulospinal projections. First, we imaged brain activation in real time during reaching motions progressively constrained by flexion synergy expression. Using this approach, we found that cortical activity indeed shifts towards the contralesional hemisphere in direct proportion to the degree of shoulder abduction loading in the contralesional arm. We then leveraged the post-stroke reemergence of a developmental brainstem reflex to show that anatomically diffuse reticulospinal motor pathways are active during synergy expression. We interpret this progressive recruitment of contralesional cortico-reticulospinal pathways as an adaptive strategy that preserves low-level motor control at the cost of fine motor control., (© 2018 Northwestern University. The Journal of Physiology © 2018 The Physiological Society.)

Microbeam radiation therapy is a novel preclinical technique, which uses synchrotron-generated X-rays for the treatment of brain tumours and drug-resistant epilepsies. In order to safely translate this approach to humans, a more in-depth knowledge of the long-term radiobiology of microbeams in healthy tissues is required. We report here the result of the characterization of the rat sensorimotor cortex tolerance to microradiosurgical parallel transections. Healthy adult male Wistar rats underwent irradiation with arrays of parallel microbeams. Beam thickness, spacing and incident dose were 100 or 600 µm, 400 or 1200 µm and 360 or 150 Gy, respectively. Motor performance was carried over a 3-month period. Three months after irradiation rats were sacrificed to evaluate the effects of irradiation on brain tissues by histology and immunohistochemistry. Microbeam irradiation of sensorimotor cortex did not affect weight gain and motor performance. No gross signs of paralysis or paresis were also observed. The cortical architecture was not altered, despite the presence of cell death along the irradiation path. Reactive gliosis was evident in the microbeam path of rats irradiated with 150 Gy, whereas no increase was observed in rats irradiated with 360 Gy.

The misidentification of one's own limb (LM) after right hemisphere stroke is a striking phenomenon that is incompletely understood. The authors prospectively studied the natural history and anatomy of LM in 36 patients with hyperacute right middle cerebral artery infarct. Unlike in previous studies, rapid clinical assessment was prioritized. The authors found LM to be common and transient, involving 61% at onset, evolving to 15% at 1 week. Voxel-based lesion-symptom mapping found supramarginal gyrus (SMG) damage associated with LM. This substantiates the SMG's importance in LM and has broader implications for lesion analysis: timing matters. Rapid assessment of transient disorders minimizes false negatives, which can improve lesion analysis.

Competing Interests: I have read and understood BMJ policy on declaration of interests and declare there are no competing interests.

Introduction: Pseudoabducens palsy refers to abduction paresis in the absence of a pontine or peripheral nerve process. This finding has been described with mesodiencephalic lesions, and likely has a common mechanism with thalamic esotropia., Case Report: We describe the case of a 55-year-old man who presented with near-complete ophthalmoparesis, sparing only adduction of the left eye. Magnetic resonance imaging of the brain demonstrated midbrain infarction., Conclusions: Pseudoabducens palsy is likely underrecognized, but can be highly localizing when identified. Possible pathophysiologic mechanisms for this finding are discussed.

Periventricular leukomalacia (PVL), a brain injury affecting premature infants is commonly associated with cerebral palsy. PVL results from hypoxia-ischemia (HI) with or without infection and is characterized by white matter necrotic lesions, hypomyelination, microglial activation, astrogliosis, and neuronal death. It is important to study a PVL mouse model that mimics human PVL in symptomatology, anatomic and molecular basis. In our neonate mice model, bilateral carotid arteries were temporary ligated at P5 followed by hypoxic exposure (FiO2 of 8% for 20 min.). At P5 in mice, the white matter is more vulnerable to HI injury than the grey matter. In our PVL model, mice suffer from significant hind limb paresis, incoordination and feeding difficulties. Histologically they present with ventriculomegally, white matter loss, microglial activation and neuronal apoptosis. HI injury increases proinflammtory cytokines, activates NF-kB, activates microglia and causes nitrative stress. All these inflammatory mediators lead to oligodendroglial injury and white matter loss. Neurobehavioral analysis in the PVL mice model at P60 showed that the HI group had a significant decrease in hind limb strength, worsening rotarod testing and worsening performance in the open field test. This new PVL model has great advantages far beyond just mimicking human PVL in clinical features and histopathology. Long term survival, the development of cerebral palsy and the ability of using this model in transgenic animals will increase our understanding of the mechanistic pathways underlying PVL and defining specific targets for the development of suitable therapeutics.

Clinical manifestations of spinal epidural hematoma are presented, and the cases mimicking acute ischemic stroke have been reviewed from the literature. Many reports described the cases of spinal epidural hematoma with acute hemiparesis mimicking ischemic stroke in which intravenous thrombolytic treatment with recombinant tissue plasminogen activator was considered. A correct diagnosis of acute ischemic stroke must be made within 4.5 hours from the onset of symptoms, a relatively short window period. A spinal epidural hematoma is a potentially important stroke mimic in a wide variety of conditions that mimic a stroke. The literature review and discussion will emphasize allowing the distinction between these hemiparetic presentation of spinal epidural hematoma and acute ischemic stroke. A spinal epidural hematoma should be considered in the differential diagnosis of patients with acute onset of hemiparesis when associated with neck pain and signs of Horner's syndrome and Brown-Sēquard syndrome.

Background: Monoparetic stroke is rare but could be misdiagnosed as peripheral neuropathy. We investigated the prevalence, lesion pattern, stroke mechanism, and long-term prognosis in patients with monoparetic stroke., Methods: 586 acute ischemic stroke patients (including 31 with monoparesis) were studied. Monoparetic stroke was defined as a motor deficit in either an arm or a leg but without facial weakness or speech disturbance. Median follow-up period was 32.0 months. Kaplan-Meier survival curves, log-rank tests, logistic regressions, and Cox proportional hazards models were used for clinical outcome analyses., Results: The mean age (313 men and 273 women) was 67.6 years. Among monoparetic patients, most had cortical (80.6%) and multiple (64.5%) lesions. The main stroke mechanisms were cardioembolism (38.7%) and large artery atherosclerosis (29.0%). Precentral gyrus with additional regions was most frequently involved in monoparesis (45.2%). Upper motor neuron signs were found in only 11 patients (35.5%). Compared with the nonmonoparetic group, these patients had better functional outcomes (6-month modified Rankin scale ≤2) and long-term survival but had comparable risks for further vascular events, including stroke recurrences., Conclusions: Although monoparetic stroke may have a better functional outcome, the risk of the further vascular event seems similar to nonmonoparetic stroke.

Background: The L25 mouse line was generated by random genomic insertion of a lens-specific transgene. Inbreeding of L25 hemizygotes revealed an unanticipated spastic phenotype in the hind limbs., Objective: The goals were to characterize the motor phenotype in the L25 mice and to map the transgene insert site within the mouse genome., Methods: Six pairs of L25+/- mice were repeatedly mated. Beginning at weaning, all progeny were inspected for body weight and motor signs twice weekly until they displayed predefined ethical criteria for termination. The transgene insert site was determined by whole genome sequencing. Western blotting was used to compare the expression levels of beta-IV spectrin protein in the brain., Results: Matings of hemizygous L25+/- × L25+/- mice yielded 20% (29/148) affected weanlings, identified by an abnormal retraction of the hind limbs when lifted by the tail, and a fine tremor. Affected mice were less mobile and grew more slowly than wild-type littermates. All affected mice required termination due to >15% loss of body weight (50% survival age 92 days). At the endpoint, mice showed varying degrees of spastic paresis or spastic paralysis localised to the hind limbs. Motor endplates remained fully innervated. Genome sequencing confirmed that the transgene was inserted in the locus of βIV spectrin of L25 mice. Western blotting indicated that this random insertion had greatly reduced the expression of βIV spectrin protein in the affected L25 mice., Conclusions: The results confirm the importance of βIV spectrin for maintaining central motor pathway control of the hind limbs, and provide a developmental time course for the phenotype.

Background: Pathogenic variants in ryanodine receptor type 1 (RYR1) gene are an important cause of congenital myopathy. The clinical, histopathologic and genetic spectrum is wide., Objective: Review a group of the patients diagnosed with ryanodinopathy in a tertiary centre from North Portugal, as an attempt to define some phenotypical patterns that may help guiding future diagnosis., Methods: Patients were identified from the database of the reference centre for Neuromuscular Disorders in North Portugal. Their data (clinical, histological and genetic) was retrospectively accessed., Results: Seventeen RYR1-related patients (including 4 familial cases) were identified. They were divided in groups according to three distinctive clinical characteristics: extraocular muscle (EOM) weakness (N = 6), disproportionate axial muscle weakness (N = 2) and joint laxity (N = 5). The fourth phenotype includes patients with mild tetraparesis and no distinctive clinical features (N = 4). Four different histopathological patterns were found: centronuclear (N = 5), central core (N = 4), type 1 fibres predominance (N = 4) and congenital fibre type disproportion (N = 1) myopathies. Each index case, except two patients, had a different RYR1 variant. Four new genetic variants were identified. All centronuclear myopathies were associated with autosomal recessive inheritance and EOM weakness. All central core myopathies were caused by pathogenic variants in hotspot 3 with autosomal dominant inheritance. Three genetic variants were reported to be associated to malignant hyperthermia susceptibility., Conclusions: Distinctive clinical features were recognized as diagnostically relevant: extraocular muscle weakness (and centronuclear pattern on muscle biopsy), severe axial weakness disproportionate to the ambulatory state and mild tetraparesis associated with (proximal) joint laxity. There was a striking genetic heterogeneity, including four new RYR1 variants.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder of upper and lower motor neurons. Mutations in the gene encoding the nuclear matrix protein Matrin 3 have been found in familial cases of ALS, as well as autosomal dominant distal myopathy with vocal cord and pharyngeal weakness. We previously found that spinal cord and muscle, organs involved in either ALS or distal myopathy, have relatively lower levels of Matrin 3 compared to the brain and other peripheral organs in the murine system. This suggests that these organs may be vulnerable to any changes in Matrin 3. In order to determine the role of Matrin 3 in these diseases, we created a transgenic mouse model for human wild-type Matrin 3 using the mouse prion promoter (MoPrP) on a FVB background.We identified three founder transgenic lines that produced offspring in which mice developed either hindlimb paresis or paralysis with hindlimb and forelimb muscle atrophy. Muscles of affected mice showed a striking increase in nuclear Matrin 3, as well as the presence of rounded fibers, vacuoles, nuclear chains, and subsarcolemmal nuclei. Immunoblot analysis of the gastrocnemius muscle from phenotypic mice showed increased levels of Matrin 3 products migrating at approximately 120 (doublet), 90, 70, and 55 kDa. While there was no significant change in the levels of Matrin 3 in the spinal cord in the phenotypic mice, the ventral horn contained individual cells with cytoplasmic redistribution of Matrin 3, as well as gliosis. The phenotypes of these mice indicate that dysregulation of Matrin 3 levels is deleterious to neuromuscular function.

To increase knee range of motion and improve gait in children with spastic paresis (SP), the semitendinosus muscle (ST) amongst other hamstring muscles is frequently lengthened by surgery, but with variable success. Little is known about how the pre-surgical mechanical and morphological characteristics of ST muscle differ between children with SP and typically developing children (TD). The aims of this study were to assess (1) how knee moment-angle characteristics and ST morphology in children with SP selected for medial hamstring lengthening differ from TD children, as well as (2) how knee moment-angle characteristics and ST morphology are related. In nine SP and nine TD children, passive knee moment-angle characteristics and morphology of ST (i.e. fascicle length, muscle belly length, tendon length, physiological cross-sectional area, and volume) were assessed by hand-held dynamometry and freehand 3D ultrasound, respectively. At net knee flexion moments above 0.5 Nm, more flexed knee angles were found for SP compared to TD children. The measured knee angle range between 0 and 4 Nm was 30% smaller in children with SP. Muscle volume, physiological cross-sectional area, and fascicle length normalized to femur length were smaller in SP compared to TD children (62%, 48%, and 18%, respectively). Sixty percent of the variation in knee angles at 4 Nm net knee moment was explained by ST fascicle length. Altered knee moment-angle characteristics indicate an increased ST stiffness in SP children. Morphological observations indicate that in SP children planned for medial hamstring lengthening, the longitudinal and cross-sectional growth of ST muscle fibers is reduced. The reduced fascicle length can partly explain the increased ST stiffness and, hence, a more flexed knee joint in these SP children., Competing Interests: All authors have declared that no competing interests exist.

Background: In some cases of refractory epilepsy, hemispherectomy is the final invasive treatment option. However, predictors of postoperative hemiparesis in these patients have not been widely studied., Objective: To investigate how the volumetric analysis of cerebral peduncles and cerebellar hemispheres in patients who have undergone hemispherectomy may determine prognostic implications for postoperative hemiparesis., Methods: Twenty-two patients who underwent hemispherectomy at our institution were retrospectively included. Using iPlan/BrainLAB (BrainLAB, Feldkirchen, Germany) imaging software and a semiautomatic voxel-based segmentation method, we calculated the preoperative cerebral peduncle and cerebellar hemisphere volumes. Cerebral peduncle and cerebellar hemisphere ratios were compared between patients with worsened or unchanged/better hemiparesis postoperatively., Results: The ratios of ipsilateral/contralateral cerebral peduncles (0.570 vs 0.828; P = .02) and contralateral/ipsilateral cerebellar hemispheres (0.885 vs 1.031; P = .009) were significantly lower in patients who had unchanged/improved hemiparesis postoperatively compared with patients who had worsened hemiparesis. Relative risk of worsening hemiparesis was significantly higher in patients with a cerebral peduncle ratio < 0.7 (relative risk, 4.3; P = .03) or a cerebellar ratio < 1.0 (relative risk, 6.4; P = .006)., Conclusion: Although patients who undergo hemispherectomy are heterogeneous, we report a method of predicting postoperative hemiparesis using only standard volumetric magnetic resonance imaging. This information could be used in preoperative discussions with patients and families to help better understand that chance of retaining baseline motor function., Abbreviations: CST, corticospinal tractfMRI, functional magnetic resonance imagingTMS, transcranial magnetic stimulation.

Objective The supplementary motor area (SMA) is important for the prediction of post-operative symptoms after surgical resection of gliomas. We investigated the relationships between clinical factors and the resection range of SMA gliomas, and the post-operative neurological symptoms. Methods We retrospectively studied 18 consecutive surgeries for gliomas involving the SMA proper performed in 13 patients. Seven cases were recurrence of the tumour. Clinical factors and details of specific resection of the SMA proper (resection of posterior part, medial wall) and cingulate motor area (CMA) were examined. Results Eight cases suffered new post-operative neurological deficits. Six of these eight cases had transient deficits. Permanent deficits persisted in two cases with partial weakness or paresis, after rapid improvement of post-operative global weakness or hemiplegia, respectively. The risk of post-operative neurological deficits was not associated with the resection of the posterior part of the SMA proper or the CMA, but was associated with resection of the medial wall of the SMA proper. Surgery for recurrent tumour was associated with post-operative neurological deficits. The medial wall was frequently resected in recurrent cases. Discussion The frequency of post-operative neurological symptoms, including SMA syndrome, may be higher after resection of the medial wall of the SMA proper compared with the resection of only the lateral surface of the SMA proper.

Introduction: Skeletal muscle is changed after stroke, but conflicting data exist concerning muscle morphology and oxidative enzyme capacity., Methods: In 36 chronic stroke patients bilateral rectus femoris muscle biopsies were analyzed, and fiber type proportions and cross-sectional areas were determined by ATPase histochemistry. Enzymatic concentrations of citrate synthase (CS) and 3-Hydroxyacyl-coenzymeA-dehydrogenase (HAD) were determined using freeze-dried muscle tissue. Findings were correlated with clinical outcomes., Results: In the paretic muscles the mean fiber area was smaller (P = 0.0004), and a lower proportion of type 1 fibers (P = 0.0016) and a higher proportion of type 2X fibers (P = 0.0002) were observed. The paretic muscle had lower CS (P = 0.013) and HAD concentrations (P = 0.037). Mean fiber area correlated with muscle strength (r = 0.43; P = 0.041), and CS concentration correlated with aerobic capacity (r = 0.47; P = 0.01)., Conclusions: In stroke survivors there is a phenotypic shift toward more fatigable muscle fibers with reduced oxidative enzymatic capacity that relates to clinical outcomes., (© 2016 Wiley Periodicals, Inc.)