Pusher Syndrome Research Articles

Abstract TP145: Anodal 2mA Transcranial Direct Current Stimulation Over Affected Parietal-Insular-vestibular Cortex Shows No Effect on Lateropulsion Following Strokei

Objective: To assess the effects of 2mA transcranial Direct Current Stimulation (tDCS) over the affected Parietal-Insular-Vestibular Cortex (PIVC) on seated posture of patients with lateropulsion following stroke. We hypothesized that bilateral electrode placement over PIVC (vs active control) would produce a change in seated posture. Background: Lateropulsion following stroke (Pusher Syndrome) is characterized by lateral displacement of subjective postural vertical toward the weak side. It is caused by lesions affecting vestibular projections to the Ventral Lateral Thalamus (VLT) or projections from the VLT to the Parietal-Insular-Vestibular Cortex (PIVC). Methods: Seventeen subjects with Burke Lateropulsion Scale scores ≥ 2 within 30 days of an ischemic stroke signed an IRB-approved consent. They received 2mA tDCS delivered using 25cm 2 saline soaked sponge electrodes via one of two montages: Test (anode over the affected PIVC and cathode opposite PIVC) versus Active Control (anode over the affected PIVC and cathode over the opposite supra-orbital region). PIVC was defined using EEG 10/20 coordinates. Seated medial-lateral center of pressure (COP-X) was measured using a custom-designed chair mounted on an AMTI™ analog-to-digital forceplate. An inclinometer strapped to the chest and aligned with the sternum measured lateral trunk tilt. Data were collected prior to, then at 5, 10, and 15 minutes during tDCS and 5 min following tDCS. Results: Repeated Measures Analysis of Variance rejected the hypothesis of an interaction between Montage and Time for: mean COP-X displacement (in) (Wilks’ λ F = 0.647 df =(4, 13), P = 0.639); mean speed of COP-X (in/s) (Wilks’ λ F = 0.740 df =(4, 13), P =0.581); mean inclinometer tilt (degrees) (Wilks’ λ F = 0.740 df =(4, 13), P =0.581). Conclusion: Neither tDCS montage showed improvement in COP-X displacement, COP-X movement velocity or inclinometer readings. These negative results are important to encourage the development of alternative tDCS stimulation parameters or identification of alternative cortical or vestibular tDCS targets for the treatment of Lateropulsion Following Stroke.

Clinical Outcome Measures for Lateropulsion Poststroke: An Updated Systematic Review.

Contraversive Lateropulsion, also referred to as contraversive pushing, pusher behavior, and pusher syndrome, can be associated with increased hospital length of stay, increased health care costs, and delayed outcomes in persons with stroke. The purpose of this updated systematic review was to identify scales used to classify contraversive lateropulsion, investigate literature that addresses their clinimetric properties, and create a resource for clinicians recommending use in clinical practice. Three databases were searched for articles from inception to March 2017. The search strategy followed Cochrane Collaboration guidelines. The Consensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was applied to evaluate methodological quality. Four hundred three records were screened. Seven studies met inclusion criteria. Four scales were identified: the Scale for Contraversive Pushing (SCP), the Modified Scale for Contraversive Pushing (M-SCP), the Burke Lateropulsion Scale (BLS), and the Swedish Scale for Contraversive Pushing (S-SCP). Psychometric property investigation was most robust for the SCP and the BLS. Cross-cultural validity has not been fully investigated in scales used outside of their country of origin. The BLS is recommended for identifying contraversive lateropulsion. The scale assesses the presence of contraversive lateropulsion across several functional tasks, from rolling to walking, and is the only scale originally written in English. The BLS is the only tool to receive ratings greater than poor for reliability and responsiveness. The BLS should be implemented as soon as contraversive lateropulsion is suspected to guide frontline clinicians' initial plan of care, allow objective identification of change over time, and facilitate easier investigation of interventional efficacy.Video Abstract available for additional insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A177).

Metavestibular disorders and disorders of higher vestibular function

Vertigo, instability, oscillopsia and concomitant autonomic disorders are classical and well-known symptoms of vestibular disorders. At the same time, recent studies suggest that there are more complicated vestibular dysfunctions caused by the cortical projections of the vestibular system. The central vestibular system includes parietal temporal cortex and insular, anterior intraparietal sulcus, posterior parietal and medial parts of the superior temporal gyrus, singular gyrus retrosplenial cortex, hippocampus and parahippocampal area. The central part of the vestibular system closely interacts with other afferent systems forming a multisensory structure of higher brain functions. Dysfunctions of higher vestibular function play an important role in the development of clinical syndromes including pusher syndrome, room tilt illusion, unilateral spatial neglect syndrome, impairment of spatial memory and navigation. These syndromes can develop due to the direct damage of the cortical vestibular system or as a result of disconnection between the vestibular cortex and other parts of the sensory cortex.

Case–Control Study of Impairments Associated with Recovery from “Pusher Syndrome” after Stroke: Logistic Regression Analyses

Comparing cohorts with similar functional and motor status at admission to inpatient rehabilitation may delineate demographics or impairments associated with recovery from lateropulsion, also known as "pusher syndrome," after stroke based on lesion side. The aim of this case-control study was to determine how demographics and severity of stroke impairments at admission to inpatient rehabilitation distinguish patients who recover from lateropulsion from those who do not. Patients with admission motor Functional Independence Measure (FIM) scores less than 31 and contralesional lower extremity Fugl-Meyer motor scores less than 19 out of 34 were included. Burke Lateropulsion Scales score of 2 or higher at the time of discharge from inpatient rehabilitation indicated persistent lateropulsion; a score of 0 or 1 indicated resolved lateropulsion. Logistic regression tests included age, gender, admission Motricity Index score, limb placement error, and cognitive FIM score. χ2 analyses compared groups for neglect. For patients with left brain lesion, older age and worse admission motor status distinguished those with persistent lateropulsion at discharge. For right brain lesion, related factors were older age, greater admission limb placement error, and lower cognitive FIM scores. Visuospatial neglect did not influence recovery from lateropulsion. Older age and severe impairments were associated with delayed recovery from lateropulsion in a manner specific to lesion side in a sample with motor and functional deficits. The study provides evidence that lesion side and admission characteristics are useful in early decision making for the duration of rehabilitation, selection of interventions, and discharge planning.

Zespół odpychania – rola koncepcji Bobath

1. Karnath HO. Pusher Syndrome – a frequent but little-known distur¬bance of body orientation perception. J Neurol. 2007; 254: 514–424. Google Scholar

Could be the predominantly-used hemibody related to the weight bearing distribution modified by the chronic hemiparesis after stroke?

Since the first Broca publications issued from 1970s, lateralized functions in the human brain have urged the researchers to postulate hypothesis based in the right-left asymmetries and, according to some theories, the lateralization of the voluntary motor control could represent a solution to avoid redundant process optimizing space and time. Supported by this idea, the clinicians and researchers tend to concept that the chronic hemiplegic stroke patients learn to use predominantly the non-affected hemibody after stroke in which is more convenient to execute their daily life activities, modifying their natural preference in some cases. Although could seems reasonable conceptualize the non-affected side as the predominantly-used hemibody for motor tasks after stroke (convenience hypothesis), evidences point to exist also hemiplegic patients that developed a predominantly use of the affected side. To float an idea, in terms of weight bearing distribution during upright position, the researchers have found patients overloading the non-affected hemibody, as expected; but also patients overloading the affected hemibody, not presenting necessarily Pusher's syndrome cases. Given the evidences, we could propose a severity-modulated predominance hypothesis which complements the convenience hypothesis. According to our complementary hypothesis, the severity of the motor disability presented in the hemiparesis condition (light, moderate and heavy severity) could determine a predominant use defined by preference (light to moderate severity) or convenience (moderate to heavy severity). In this hypothesis, we postulate ideas from a rehabilitation perspective to be incorporated in treatment programs.

Study of the burke lateropulsion scale to evaluate Pusher syndrome rehabilitation

Background: Pusher syndrome is a position-control disorder with a higher incidence in patients after stroke. Clinical studies have shown that patients with Pusher syndrome hospitalize for a long time and daily function after discharge are low, so early detection and treatment is critical to control the development of the disease; Burke lateropulsion scale (BLS) can be used to diagnose Pusher syndrome and can effectively and accurately reflect the changing aspects of patient movement, but now BLS has not been widely used in clinical work. Purpose:To study about the sensitivity ofBLSon changes ofPusher syndromeand the clinical features in the application of BLS as the evaluation tool in order to provide a theoretical basis for BLS’s clinical application. Methods: Patients were scored by BLS since the first day of admission, and in every two weeks till discharged. After admission, conventional motor function training were given, motor relearning and Bobath therapy mainly, including rollover, stand-up, sit-up, sit station transfer, balance training, walking training, etc. Each patient has been evaluated at least three times during hospitalization. Results: Of 48 patients, 56.3% were evaluated as mild of Pusher syndrome and 16.7% severe at admission. While at discharge, 47.9% were classified as mild, 43.8% were not diagnosed as Pusher syndrome and none severe. SRM was 1.27 during the whole hospitalization, 1.41 in 4 weeks and 2.18 in 6 weeks. Conclusion(s): The BLS is an appropriate tool for the evaluation of Pusher syndrome patients and is responsive to monitor progress and recovery during rehabilitation. It is significant to guide rehabilitation if used in routine clinical practice. It could be suitable to evaluate changes in future intervention studies. Implications: With the wide and routine use of BLS in patients after stroke, especially in those with Pusher syndrome, it will be a sensitive tool in monitor the progress during rehabilitation which gives an accurate feedback on therapy and helps with the treatment prescription adjustment in time.

Effects of interactive visual feedback training on post-stroke pusher syndrome: a pilot randomized controlled study

Objective: We investigated the effects of a computer-generated interactive visual feedback training program on the recovery from pusher syndrome in stroke patients. Design: Assessor-blinded, pilot randomized controlled study. Participants: A total of 12 stroke patients with pusher syndrome were randomly assigned to either the experimental group (N = 7, computer-generated interactive visual feedback training) or control group (N = 5, mirror visual feedback training). Main outcome measures: The scale for contraversive pushing for severity of pusher syndrome, the Berg Balance Scale for balance performance, and the Fugl-Meyer assessment scale for motor control were the outcome measures. Patients were assessed pre- and posttraining. Results: A comparison of pre- and posttraining assessment results revealed that both training programs led to the following significant changes: decreased severity of pusher syndrome scores (decreases of 4.0 ±1.1 and 1.4 ±1.0 in the experimental and control groups, respectively); improved balance scores (increases of 14.7 ±4.3 and 7.2 ±1.6 in the experimental and control groups, respectively); and higher scores for lower extremity motor control (increases of 8.4 ±2.2 and 5.6 ±3.3 in the experimental and control groups, respectively). Furthermore, the computer-generated interactive visual feedback training program produced significantly better outcomes in the improvement of pusher syndrome (p < 0.01) and balance (p < 0.05) compared with the mirror visual feedback training program. Conclusions: Although both training programs were beneficial, the computer-generated interactive visual feedback training program more effectively aided recovery from pusher syndrome compared with mirror visual feedback training.

The role of the thalamus in the human subcortical vestibular system.

Most of our knowledge concerning central vestibular pathways is derived from animal studies while evidence of the functional importance and localization of these pathways in humans is less well defined. The termination of these pathways at the thalamic level in humans is even less known. In this review we summarize the findings concerning the central subcortical vestibular pathways in humans and the role of these structures in the central vestibular system with regard to anatomical localization and function. Also, we review the role of the thalamus in the pathogenesis of higher order sensory deficits such as spatial neglect, pusher syndrome or thalamic astasia and the correlation of these phenomena with findings of a vestibular tone imbalance at the thalamic level. By highlighting thalamic structures involved in vestibular signal processing and relating the different nomenclatures we hope to provide a base for future studies on thalamic sensory signal processing.

Recovery from Neglect after Right Hemisphere Stroke

Favourable outcome after cerebrovascular stroke is associated with early admission to rehabilitation, small lesion size and minor cognitive impairment. The aim of the present study was to explore factors associated with the amelioration of neglect after right hemisphere stroke. Twenty-one consecutive eligible right hemisphere stroke patients in one rehabilitation center were assessed and followed for 6 months. The neglect syndrome was assessed by the conventional subtests of the Behavioural Inattention Test (BIT) and by the Catherine Bergego Scale (CBS) before and after the 3-week rehabilitation and at 6-month follow-up. The manifestations of extinction, pusher syndrome and depression were evaluated. Recovery from neglect was strongly associated with early rehabilitation and the initial severity of neglect. Intensive treatment yielded recovery in severe or moderate visual neglect long after the first two to three months after stroke. Even chronic patients with sufficient cognitive and psychological capacity improved with intensive rehabilitation. Tactile extinction was common in these patients but was not associated with recovery. Manifestations of pusher syndrome hampered amelioration of visual neglect in acute and sub-acute stroke patients, whereas depression did not prevent recovery from neglect. Intensive rehabilitation promotes recovery from neglect in the acute phase after right hemisphere stroke. A comprehensive program later, in sub-acute or chronic phase, may also be effective especially in those patients who have not received intensive multi-professional rehabilitation soon after the stroke.

Avaliação da Percepção Corporal em Pacientes Pós-Acidente Vascular Cerebral (AVC)

The Cerebral Vascular Accident (CVA) is a pathological condition whose main consequence hemiplegia abnormality characterized by paralysis and/or paresis of the contralateral brain injury. Hemiple­gia affects body awareness and alignment, changing the whole chain muscle and body posture against gravity. In Pusher syndrome (SP), a set of characteristics leads patients to make a strong body tilt toward the paralyzed side. The purpose of the research, characterized as ex­ploratory, descriptive, quantitative character, was to assess the degree of impairment of body awareness in post-stroke patients, treated at the Clinical School of Physiotherapy Univates / Paved / RS during the semester B 2012 whose instrument of data collection was the Clinical Scale for Contraversive Pushing (CSCP), the protocol provided three stages: sitting position, standing position and during active movement of the upper limb (UL) unaffected. Of the thirteen patients evaluated (8 men and 5 women), the results show that five have changes of body awareness. Seven have impaired left body half and eight strokes were ischemic. Conclusion. SP is a disorder present in these subjects, the CSPS is a protocol for easy application, which favors the identification and severity of this change.

Postural instability after acute ischemic stroke

Postural instability after acute ischemic stroke

Postural instability after acute ischemic stroke

A 63-year-old man attended the emergency department 6 hours after sudden onset of severe right hemiparesis and dysarthria. He had no significant medical history and presented no known cardiovascular risk factors apart from chronic alcohol abuse. He also had no medication history. Blood pressure was 170/94 mmHg, pulse was regular at 75 beats per minute, and heart sounds were normal. There were no cervical or femoral bruits, and no signs of heart failure. On neurological examination, the patient was alert with right lower facial paresis and dysarthria. Motor examination revealed diminished tone in his right arm and leg. Sensory and visual examinations were normal. His National Institutes of Health Stroke Scale (NIHSS) score was 11/42. Initial laboratory work-up (including complete blood count, electrolytes, blood glucose, and renal function), chest radiograph, and electrocardiogram were normal. A head CT scan did not reveal any early signs of cerebral ischemia. Brain MRI was performed 9 hours after symptom onset and showed a limited acute infarct in the posterior part of the left centrum ovale (Fig. 1A). Magnetic resonance angiography was normal. Carotid ultrasonography and transthoracic echocardiography were normal. Transesophageal echocardiography was not performed. Twenty-four hours after admission to our stroke unit, when sitting or standing, the patient was observed to abduct and extend his non-paretic limbs in order to actively thrust towards his paretic side and resisted all attempts to passively correct his body posture (Fig. 1B, Supp. Video 1). As the patient presented severe motor weakness on the right side associated with postural instability, he was transferred to a rehabilitation center on aspirin (300 mg/ day), atorvastatin (40 mg/day), angiotensin-converting-enzyme inhibitor (perindopril, 5 mg/day), and non-thiazide diuretic (indapamide, 1.5 mg/day). Following intensive physiotherapy, the patient was discharged 90 days after admission with a favorable outcome (NIHSS score 3/42). No new symptoms appeared during 6 months of outpatient follow-up.

Somatosensory Findings of Pusher Syndrome in Stroke Patients

ObjectiveTo investigate the somatosensory findings of pusher syndrome in stroke patients.MethodsTwelve pusher patients and twelve non-pusher patients were enrolled in this study. Inclusion criteria were unilateral stroke, sufficient cognitive abilities to understand and follow instructions, and no visual problem. Patients were evaluated for pusher syndrome using a standardized scale for contraversive pushing. Somatosensory finding was assessed by the Cumulative Somatosensory Impairment Index (CSII) and somatosensory evoked potentials (SEPs) at 1 and 14 weeks after the stroke onset. Data of SEPs with median and tibial nerve stimulation were classified into the normal, abnormal, and no response group.ResultsIn the baseline characteristics (sex, lesion character, and side) of both groups, significant differences were not found. The score of CSII decreased in both groups at 14 weeks (p<0.05), but there were no significant differences in the CSII scores between the two groups at 1 and 14 weeks. There were no significant differences in SEPs between the two groups at 1 and 14 weeks after the stroke onset.ConclusionIt appears that somatosensory input plays a relatively minor role in pusher syndrome. Further study will be required to reveal the mechanism of pusher syndrome.

Progress in neuro-otology research in the last year

Herein, we summarize articles in the field of neuro-otology published in the Journal of Neurology over the last year. Topics included acute and chronic vertigo as well as auditory and ocular motor disorders. Characteristic lesion locations in Pusher syndrome are reported and the usefulness of bedside ocular motor tests in vertebrobasilar stroke is revisited. Probing the vestibular system and its value in predicting the outcome in vegetative state is discussed. Several articles address new diagnostic and therapeutic approaches in different disorders associated with chronic vestibular, auditory or gait deficits. In a series of case reports, we focus on different eye movement disorders in the vertical plane, which are often difficult to assess.

Letter by Santos-Pontelli et al Regarding Article, “Prevalence and Length of Recovery of Pusher Syndrome Based on Cerebral Hemispheric Lesion Side in Patients With Acute Stroke”

To the Editor: We read with interest the article by Abe et al1 regarding the prevalence and length of recovery of pusher behavior (PB) in patients with acute stroke. Their retrospective cohort study included 1660 patients with acute stroke. According to authors, study subjects were daily assessed for PB and were assessed during their initial physical therapy for lower limb impairments, presence of sensory deficits “and/or” neglect, degree of consciousness disorder, and activities of daily living function. They found higher prevalence and length of recovery of the PB in patients with right cerebral hemisphere stroke. The length of recovery of PB (and other neurological deficits) has been associated with several aspects such as physiotherapy, previous encephalic lesions, nonneurological clinical …

Response to Letter Regarding Article, “Prevalence and Length of Recovery of Pusher Syndrome Based on Cerebral Hemispheric Lesion Side in Patients With Acute Stroke”

Response: We thank Santos-Pontelli et al for their interest and comments on our recent article. Because our investigation was performed retrospectively, frequency and duration of physical and occupational therapy sessions could not be controlled. At our institution, physical and occupational therapy sessions are conducted on weekdays during hospital stay, and duration of each session is recorded. No significant difference was observed in the total duration of physical and occupational therapy sessions between 27 patients with pushing behavior in whom the right cerebral hemisphere was damaged (PBRHD) and 8 patients with pushing behavior in whom the left cerebral hemisphere was damaged (PBLHD; PBRHD: 1566.7±888.4 minutes, PBLHD: 1042.5±514.1 minutes, P =0.123, unpaired t test). In addition, no significant differences were observed in the number of sessions of physical therapy (PBRHD: 18.19±7.6, PBLHD: 17.1±3.6, P =0.590), the number of sessions of occupational therapy …

Posterior pusher syndrome — case report

Abstract Pusher syndrome is classically described as disorder of body orientation in the coronal plane. It is characterized by a tilt towards the contralesional paretic side and a resistance to external attempts to rectify. It occurs mainly in stroke patients, however, non-stroke causes have been described too. In 2010 the concept of the posterior pusher syndrome had been proposed, defined as disturbance of body orientation in the sagittal plane with imbalance, posterior tilt and an active resistance to forward pulling or pushing. The author describes, on the basis of the literature and own research, symptoms and methods of the treatment of the little-known posterior pusher syndrome.

Prevalence and Length of Recovery of Pusher Syndrome Based on Cerebral Hemispheric Lesion Side in Patients With Acute Stroke

The aim of this study was to determine if side of cerebral hemisphere lesion affects the prevalence and time course of pushing behavior (PB) after stroke. A total of 1660 patients with acute stroke were investigated. PB was assessed using the standardized Scale for Contraversive Pushing. Risk ratios were used to evaluate the differences in the prevalence of PB between right cerebral hemisphere-damaged (RCD) and left cerebral hemisphere-damaged (LCD) patients. The differences in the time course among 35 (27 RCD and 8 LCD) patients were evaluated by analyzing Scale for Contraversive Pushing scores with the Kaplan-Meier method using a log-rank test. PB was observed in 156 (9.4%) patients. The prevalence of PB was significantly higher in RCD (97 of 556 [17.4%]) than in LCD (57 of 599 [9.5%]) patients; risk ratio was 1.83 (95% CI, 1.35-2.49). The log-rank test indicated that RCD patients exhibited a significantly slower recovery than LCD patients (P=0.027). The number of RCD patients who exhibited PB was higher than that of LCD patients. The duration of recovery from PB was longer in RCD patients than in LCD patients.

Responsiveness of 2 Scales to Evaluate Lateropulsion or Pusher Syndrome Recovery After Stroke

Clark E, Hill KD, Punt TD. Responsiveness of 2 scales to evaluate lateropulsion or pusher syndrome recovery after stroke. Objectives To analyze responsiveness to change of 2 outcome measures in the lateropulsion population after stroke. Lateropulsion describes an atypical balance problem after stroke where patients actively push themselves toward their paretic side. Secondary aims were to measure the incidence of lateropulsion and evaluate the site of the brain most commonly involved in lateropulsion. Design Stroke patients were screened for lateropulsion on admission to rehabilitation. Those demonstrating lateropulsion were assessed every 2 weeks using 2 scales to measure progress. Analysis of variance and the standardized response mean (SRM) were used to analyze change for each scale. Setting Rehabilitation and geriatric units. Participants Prospective purposive sample of stroke patients (N=43) demonstrating lateropulsion on admission from a consecutive admission sample of 160. To allow comparison, data from 43 stroke patients who did not display lateropulsion were collected retrospectively, matched on age (±5y) and sex. Interventions Not applicable. Main Outcome Measures Incidence of lateropulsion was calculated as a percentage of stroke patients admitted. Responsiveness to change was measured by using the Burke Lateropulsion Scale (BLS), to quantify severity of lateropulsion, and the Postural Assessment Scale for Stroke (PASS), which measures postural abilities. Results Of 160 stroke patients, 26.9% displayed lateropulsion (mean age, 72y; 51% men). The BLS and PASS had high levels of measurement responsiveness (BLS SRM =1.48 and 2.24; PASS SRM =1.76 and 1.87) at 4 and 8 weeks, respectively. Conclusions The BLS and PASS are responsive scales to monitor progress and recovery during rehabilitation. As more than 25% of stroke patients admitted to rehabilitation may exhibit lateropulsion, these 2 scales could be valuable in monitoring progress and designing future intervention studies.