Contraversive Pushing and Inattention of the Contralesional Hemispace

Feedback Interventions in Motor Recovery of Lateropulsion after Stroke: A Literature Review and Case Series

Lateropulsion is a post-stroke phenomenon marked by an active push of the body across the midline towards the more affected side and/or a resistance of the weight shift towards the less affected side. Within the mechanisms of treatment, feedback systems have been shown to be effective. The aim of the present study was to create a body of knowledge by performing a literature review on the use of feedback mechanisms in the treatment of lateropulsion and to report two cases of lateropulsion patients who had undergone feedback-based treatment.

METHODS

The review was performed across five different databases (Embase, Medline/PubMed, Scopus, Web of Science, and PEDro) up to February 2024, and haptic feedback intervention was incorporated into the case series (with lateropulsion and ambulation capacity as the main variables).

RESULTS

In total, 211 records were identified and 6 studies were included after the review of the literature. The most used feedback modality was visual feedback. In the case series, positive results were observed from the intervention, particularly in the recovery of lateropulsion and balance, as well as in the improvement of gait for one patient. Patients demonstrated good adherence to the intervention protocol without adverse effects.

CONCLUSIONS

Visual feedback is the most commonly used feedback modality in lateropulsion patients but other mechanisms such as haptic feedback also are feasible and should be taken into account. Larger sample sizes, extended follow-up periods, and the isolation of feedback mechanisms must be established to clarify evidence.

The Association of Personal Neglect with Motor, Activities of Daily Living, and Participation Outcomes after Stroke: A Systematic Review

Despite its potential clinical impact, the association of personal neglect (PN) with motor, activities of daily living (ADL), and participation outcomes after stroke is not well-understood. This first-ever systematic review on the topic therefore evaluates this association, taking into account suggested subtypes of PN, including body representation neglect, somatosensory neglect, motor neglect, and premotor neglect. A systematic literature search was conducted on February 17, 2023 in PubMed, Web of Science, Scopus, PubPsych, and PsycArticles databases. The study adheres to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, and its protocol was registered on PROSPERO (CRD42020187460). Eleven observational studies were included, gathering 1,400 individuals after stroke (429 showed PN). Results show that individuals with body representation neglect after stroke have significantly decreased movement control and motor strength, lower functional mobility, and ADL independency compared with those without body representation neglect after stroke. Individuals with motor neglect after stroke showed worse motor function and spasticity than to those without motor neglect after stroke. Nonspecified PN (i.e., PN evaluated with an outcome measure that does not allow subcategorization) was related to worse lateropulsion with pushing, longer length of stay and greater odds of being discharged to somewhere other than home. No study evaluated somatosensory and premotor neglect. This review highlights the limited research in this area and emphasizes the need for a more comprehensive PN assessment. However, currently available assessment tools show limited ability to accurately diagnose PN subtypes and future research should prioritize the development of comprehensive diagnostic test batteries.

Lateropulsion with active pushing in stroke patients: its link with lesion location and the perception of verticality. A systematic review

BACKGROUND

Lateropulsion with active Pushing (LwP) is characterized by impairments in postural control. Previous research suggests an association between LwP, lesion location and verticality misperception. This first-ever systematic review evaluates the association between LwP, lesion location and the perception of verticality (PROSPERO: CRD42020159248).

METHODS

PubMed, Web of Science, REHABDATA, Embase, Cochrane Library and PEDro were systematically searched on December 16, 2021. Studies were included when examining lesion location or perception of verticality (Subjective Haptic, Visual or Postural Vertical) in supratentorial stroke patients showing LwP. Two reviewers independently screened and assessed risk of bias using the Newcastle Ottawa Scale. Data were qualitatively analyzed and extracted.

RESULTS

Nineteen studies were included, examining a total of 340 LwP patients. Lesions in: the thalamus, internal capsule, inferior parietal lobule at the junction of the postcentral gyrus, the posterior insula and the superior temporal gyrus, were associated with LwP. Whereas all studies examining the Subjective Postural and Haptic Vertical (haptic only examined once) reported a significant increased deviation in LwP patients, inconsistent results were found for the Subjective Visual Vertical. Furthermore, the Subjective Visual and Postural Vertical showed inconsistent results for magnitude, direction and variability of this deviation.

DISCUSSION

A complex brain network, rather than only one brain region, seems responsible for body control with respect to gravity. A disruption within this network might lead to a bias in the construction of a correct internal reference frame, crucial for perceiving verticality. There was an association of LwP with verticality misperception in all three modalities.

Lateropulsion Prevalence after Stroke: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Lateropulsion is a deficit of active body orientation with respect to gravity in the frontal plane, mostly observed after a stroke. It magnifies mobility limitations and so represents an emerging target in rehabilitation. Efforts to design specific interventional studies require some basic knowledge of epidemiology, which is insufficient today because many studies focused on a few severe forms in individuals called pushers. The objectives of this study were to bridge this gap.

METHODS

We systematically searched MEDLINE, EMBASE, CINAHL, and Cochrane Clinical Trials up to 31 May 2021 for original research reporting a prevalence or incidence of post-stroke lateropulsion. We followed MOOSE and PRISMA guidelines. Eligibility for inclusion, data extraction, and study quality (Joanna Briggs Institute guidelines) were evaluated by two reviewers who used a standardized protocol: PROSPERO (CRD42020175037). A random-effects meta-analysis was used to obtain the pooled prevalence, whose heterogeneity was investigated by subgroup analysis (stroke locations and post-stroke phases) and meta-regression.

RESULTS

We identified 22 studies (5125 individuals; mean age 68.5 years; 42.6% female; assessed 24 days, on average, after stroke), most published after 2000. The studies' quality was adequate, with only 8 (36.4%) showing risk of bias. The pooled lateropulsion prevalence was 55.1% (95% confidence interval [CI] [35.9-74.2]) and was consistent across assessment tools. After supratentorial stroke, lateropulsion prevalence was 41% (95%CI [33.5-48.5]), and only 12.5% (95%CI [9.2-15.9]) in individuals with severe lateropulsion, called pushers. Meta-regression did not reveal any effect of age, sex, geographic region, publication year, or study quality. Lateropulsion prevalence progressively decreased from 52.8% (95%CI [40.7-65]) in the acute phase to 37% (95%CI [26.3-47.7]) in the early subacute phase and 22.8% (95%CI [0-46.3]) in the late subacute phase. The ratio of right- to left-hemispheric stroke with lateropulsion increased as a function of time: 1.7 in the acute phase to 7.7 in the late subacute phase. After infratentorial stroke, lateropulsion prevalence was very high, reaching 83.2% (95%CI [63.9-100.3]).

CONCLUSIONS

Post-stroke lateropulsion prevalence is high, which appeals for its systematic detection to guide early interventions. Uprightness is predominantly controlled from the right hemisphere.

Preexisting brain lesions in patients with post stroke pusher behavior and their association with the recovery period: A one year retrospective cohort study in a rehabilitation setting

The presence of preexisting brain lesions due to previous stroke and cerebral small vessel disease has been reported to influence stroke related disability or rehabilitation outcomes. However, there is no data about the impact of such lesions on the recovery period after pusher behavior (PB). This retrospective cohort study aimed to determine the influence of preexisting brain lesions on PB recovery time. Nineteen patients who were suffering from PB were included in the study. The presence of preexisting brain lesions, including previous stroke, silent brain infarcts, microbleed, white matter hyperintensity, and enlarged perivascular spaces were assessed using medical history reports, radiological reports, and magnetic resonance imaging data. The lesion score, ranging from 0 to 6, was calculated based on each preexisting brain lesion. The time to recovery from PB was assessed using the Scale for Contraversive Pushing. Based on the median value of the lesion score, we divided patients into those with a lesion score <2 and those with a lesion score ≥2. A Kaplan Meier survival analysis was performed between these two groups. A multivariable Cox proportional hazards analysis was also performed using the side with hemiparesis and the score of preexisting brain lesions as covariates to determine the hazard ratio. The results showed that the group with a lesion score ≥2 had significantly delayed recovery from PB and the hazard ratio of preexisting brain lesions score was 0.458 (95 % confidence interval: 0.221, 0.949), while the side of hemiparesis was not identified a significant covariate. Our results indicated that patients with PB having higher score of preexisting brain abnormalities might require a longer time to recover, and this might be useful in planning inpatient rehabilitation and treatment goals for patients with PB.

Scale for contraversive pushing in stroke patients: pusher behavior vs Thalamic astasia differential diagnosis and psychometric properties

BACKGROUND

: Few studies have investigated the psychometric properties of the Scale for Contraversive Pushing (SCP) in depth, and none have evaluated its ability to establish differential diagnosis between pusher behavior (PB) and thalamic astasia (TA).

OBJECTIVES

: To study the ability of the SCP to establish differential diagnosis, its reliability, content, construct, and internal validity in the assessment of subacute stroke patients.

METHODS

: 120 individuals were evaluated using the SCP over a four-week period of treatment. Intra- and inter-observer reliability, floor and ceiling effects, minimum detectable change (MDC), internal validity and sensitivity to change were explored. In addition, the Barthel Index and the Trunk Control Test were used to study their correlations with the SCP.

RESULTS

: Discriminant validity provides evidence that the correlation between SCP items was large or moderate. Convergent validity demonstrated that the correlation of each item with the total score of the scale was high (at around 0.8). Sensitivity to change was large (W = 0.274). Intra- and inter-observer reliability were excellent (Intraclass Correlation Coefficient > 0.9; k > 0.8), except for items B standing and C sitting (k > 0.7). The MDC was 1.39, and ceiling (8.333%) and floor (15.833%) effects were adequate. Cronbach's alpha (α) was equal to 0.901 (0.874-0.924) and McDonald's Omega (ω) was equal to 0.883 (0.856-0.973), showing excellent internal consistency.

CONCLUSIONS

: The SCP is a reliable and valid tool which can successfully establish differential diagnosis between PB and TA and evaluate the changes generated by physiotherapy treatment.

Post-stroke lateropulsion and rehabilitation outcomes: a retrospective analysis

PURPOSE

A person with post-stroke lateropulsion actively pushes themselves toward their hemiplegic side, or resists moving onto their non-hemiplegic side. This study aimed to determine the association of lateropulsion severity with: • Change in function (Functional Independence Measure - FIM) and lateropulsion severity (Four-Point Pusher Score - 4PPS) during inpatient rehabilitation; • Inpatient rehabilitation length of stay (LOS); • Discharge destination from inpatient rehabilitation.

METHODS

Retrospective data for 1,087 participants (aged ≥65 years) admitted to a stroke rehabilitation unit (2005-2018) were analysed using multivariable regression models.

RESULTS

Complete resolution of lateropulsion was seen in 69.4% of those with mild lateropulsion on admission (n = 160), 49.3% of those with moderate lateropulsion (n = 142), and 18.8% of those with severe lateropulsion (n = 181). Average FIM change was lower in those with severe lateropulsion on admission than those with no lateropulsion (p < 0.001). Higher admission 4PPS was associated with reduced FIM efficiency (p < 0.001), longer LOS (p < 0.001), (adjusted mean LOS: 35.6 days for those with severe lateropulsion versus 27.0 days for those without), and reduced likelihood of discharge home (p < 0.001).

CONCLUSION

Post-stroke lateropulsion is associated with reduced functional improvement and likelihood of discharge home. However, given a longer rehabilitation duration, most stroke survivors with moderate to severe lateropulsion can achieve important functional improvement.Implications for RehabilitationWhile people with post-stroke lateropulsion can be difficult to treat and require more resources than those without lateropulsion, the majority of those affected, even in severe cases, can make meaningful recovery with appropriate rehabilitation.Although those with moderate to severe post-stroke lateropulsion may have poorer outcomes (longer LOS and reduced likelihood of discharge home) it is still important to advocate for access to rehabilitation for this patient group to give them the opportunity for optimal functional recovery.

Prevalence of spatial neglect post-stroke: A systematic review

OBJECTIVE

Spatial neglect (SN) impedes stroke rehabilitation progress, slows functional recovery, and increases caregiver stress and burden. The estimation of SN prevalence varies widely across studies.

BACKGROUND

We aimed to establish the prevalence of SN based on the injured cerebral hemisphere, recovery stage post-stroke, and diagnostic methodology.

MATERIALS AND METHODS

All journal articles published up to February 27, 2019 from CINAHL, PsycINFO, PubMed and Web of Science were searched. We selected original research articles that described observational studies, included both individuals with left brain damage (LBD) and those with right brain damage (RBD) post-stroke, and reported specific diagnostic methods for SN. All authors reached consensus for the final selection of 41 articles. Time post-stroke, patient selection criteria, study setting, SN diagnostic methods were extracted.

RESULTS

A total of 6324 participants were included: 3411 (54%) with RBD and 2913 (46%) with LBD. Without considering time post-stroke or diagnostic methods, the occurrence rate of SN was 29% (38% after RBD and 18% after LBD). Using ecological assessments resulted in higher prevalence than using tests not directly related to daily life activities (53% vs. 24%). Using methods based on a single-cutoff criterion led to lower occurrence of SN than using multi-test methods (27% vs. 33%). The prevalence decreased from the acute to chronic stage post-stroke.

CONCLUSIONS

The estimated prevalence of SN after unilateral stroke is 30%. SN is more common after RBD than after LBD, but SN after LBD is still quite common. Using ecological assessments and multi-test methods to detect SN is preferred to using a single-cutoff criterion of a test that is not directly related to daily function. The decrease in SN prevalence over time is evident, but the exact prevalence in later stages cannot be estimated. More research is needed to better understand chronic SN.

Sensory information and the perception of verticality in post-stroke patients. Another point of view in sensory reweighting strategies

INTRODUCTION

Perception of verticality is highly related to balance control in human. Head-on-body tilt <60° results in the E-effect, meaning that a tilt of the perceived vertical is observed contralateral to the head tilt in the frontal plane. Furthermore, somatosensory loss also impacts the accuracy of verticality perception. However, when several input sources are absent or biased, less options for sensory weighting and balance control occur. Therefore, this study aims to identify the E-effect and assess the effect of somatosensory loss on the extent of the E-effect.

METHODS

All patients with a first stroke admitted to a Belgian rehabilitation hospital were eligible for inclusion. Patients aged above 80 with other neurological and orthopaedic impairments as well as brainstem, cerebellar or multiple lesions were excluded. In addition, patients with visuospatial neglect and pusher behaviour were also excluded as this can affect verticality perception. The Rivermead Assessment of Somatosensory Performance (RASP), the Subjective Visual (SVV) and Subjective Postural (SPV) Vertical Test were administered.

RESULTS

In total, 37 patients were included in the analysis of which 24 patients completed both SVV and SPV assessment. Results show that the E-effect occurred in our sample of stroke survivors for both SVV and SPV. In addition, the presence of somatosensory loss will increase the E-effect in both SVV as SPV assessment. A significant difference in verticality perception was noted for both SVV and SPV between the group with no (SVV: 5.13°(6.92); SPV: 0.30°(1.85)) and highly severe (SVV: 10.54°(13.19); SPV: 5.96°(9.27)) sensory loss.

CONCLUSIONS

The E-effect occurs in stroke subjects and increases when patients experience somatosensory loss. This suggests that the lack of available afferent information impede estimation of verticality. Therefore, stroke survivors have fewer alternative input sources as a result of impairments, leading to fewer options about sensory reweighting strategies and balance recovery after perturbations.

Stroke

Stroke, or cerebrovascular accident, involves injury to the central nervous system as a result of a vascular cause, and is a leading cause of disability worldwide. People with stroke often experience sensory, cognitive, and motor sequelae that can lead to difficulty walking, controlling balance in standing and voluntary tasks, and reacting to prevent a fall following an unexpected postural perturbation. This chapter discusses the interrelationships between stroke-related impairments, problems with control of balance and gait, fall risk, fear of falling, and participation in daily physical activity. Rehabilitation can improve balance and walking function, and consequently independence and quality of life, for those with stroke. This chapter also describes effective interventions for improving balance and walking function poststroke, and identifies some areas for further research in poststroke rehabilitation.

Time to Recovery From Lateropulsion Dependent on Key Stroke Deficits

Background. Lateropulsion, a postural control disorder, delays recovery following hemispheric stroke. The number of stroke impairments may lead to differential recovery rates, depending on the intact systems available for recovery from lateropulsion. Objective. To study the impact of key postural control deficits on lateropulsion rate of recovery following stroke. Methods. Through retrospective analysis: 169 patients with hemispheric stroke in an in-patient rehabilitation facility were divided into 3 groups: (1) motor deficits only; (2) motor and hemianopic or visual–spatial deficits or motor and proprioceptive deficits; and (3) motor, proprioceptive, and hemianopic or visual–spatial deficits. Kaplan–Meier survival analysis determined if time to recovery from lateropulsion (achieving a score of 0 or 1 on the Burke Lateropulsion Scale) differed by group. Results. Log rank tests showed that time to recovery from lateropulsion differed based on the number of deficits (group, P = .012). Post hoc analyses by lesion side showed that group differences only occurred in right brain lesion ( P < .05) as compared with left brain lesions ( P = .34). Patients recovered from lateropulsion during in-patient rehabilitation if they had only motor deficits; those with all 3 postural control deficits showed the most protracted recovery. Conclusions. Rate of recovery from lateropulsion after stroke is dependent on the side of lesion, and number of key motor, proprioceptive, and/or hemianopic or visual–spatial deficits. The more postural control systems affected, the slower the recovery. Our data identify patients likely to need protracted rehabilitation targeting key postural control deficits.

Posterior pusher syndrome — case report

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.

Neuroimaging in stroke and non-stroke pusher patients

Pusher behavior (PB) is a disorder of postural control affecting patients with encephalic lesions. This study has aimed to identify the brain substrates that are critical for the occurrence of PB, to analyze the influence of the midline shift (MS) and hemorrhagic stroke volume (HSV) on the severity and prognosis of the PB. We identified 31 pusher patients of a neurological unit, mean age 67.4±11.89, 61.3% male. Additional neurological and functional examinations were assessed. Neuroimaging workup included measurement of the MS, the HSV in patients with hemorrhagic stroke, the analysis of the vascular territory, etiology and side of the lesion. Lesions in the parietal region (p=0.041) and thalamus (p=0.001) were significantly more frequent in PB patients. Neither the MS nor the HSV were correlated with the PB severity or recovery time.

Diretrizes para avaliação e tratamento fisioterapêutico da Síndrome de Pusher: estudo de caso

A Síndrome de Pusher (SP) é uma alteração perceptual presente em 10% dos casos de hemiparesia causada por Acidente Vascular Encefálico (AVE). Caracteriza-se por queda para o lado parético, comportamento de empurrar-se para o lado acometido com o hemicorpo não parético e resistência à correção externa. Este estudo visou descrever a avaliação, o tratamento e a evolução de uma paciente com hemiparesia à esquerda e SP, devido a um AVE no hemisfério cerebral direito. Seis meses após a lesão, a paciente realizou testes perceptuais (do desenho da figura humana, comportamental de inatenção, escala de avaliação do sintoma de empurrar, miniexame do estado mental) e de desempenho funcional (escala de avaliação postural para pacientes com AVE, teste de função manual de Jebsen-Taylor, medida de independência funcional e índice de Barthel) e iniciou fisioterapia duas vezes por semana. Cada sessão teve 3 partes de 20 minutos: estimulação sensorial, treino motor e integração sensório-motora. Após o tratamento a paciente foi reavaliada e apresentou melhora em todas as escalas. A de avaliação do sintoma de empurrar e o teste de função manual de Jebsen-Taylor foram os que registraram maiores percentuais de melhora, 79% e 46%, respectivamente. O protocolo utilizado, mesmo tendo sido iniciado seis meses após a lesão, proporcionou melhora perceptual e funcional, o que sugere a importância da fisioterapia na recuperação da SP.

Scale for contraversive pushing: cutoff scores for diagnosing "pusher behavior" and construct validity

BACKGROUND AND PURPOSE

Considerable disagreement exists among researchers with regard to the prevalence, pathophysiology, and treatment of "pusher behavior" (PB), partly because of different testing procedures. This study was primarily aimed at establishing cutoff scores for and the construct validity of the Scale for Contraversive Pushing (SCP). The prevalence of PB in people with right- and left-brain lesions also was investigated.

SUBJECTS AND METHODS

The study subjects were 105 consecutive patients with recent stroke. Two methods were used to diagnose PB: clinical examination and SCP score with 3 different cutoff points--an SCP total score of greater than 0 (Crit_1), subscores in each section of the scale of greater than 0 (Crit_2), and subscores in each section of the scale of > or =1 (Crit_3). Clinical and SCP diagnoses were independently made by different examiners. The Cohen kappa coefficient was used to determine the agreement between clinical and SCP diagnoses. The construct validity of the SCP was estimated by calculation of Spearman rank correlation coefficients for SCP and balance, mobility, and functional scores.

RESULTS

The agreement between clinical and SCP diagnoses was low (kappa=.212) when Crit_1 was used. Crit_2 led to the highest agreement with the clinical diagnosis (kappa=.933). However, only Crit_3, although globally less accurate (kappa=.754), ensured no false-positive results. The construct validity of the SCP was demonstrated by significant (P<.001) moderate to high correlations with mobility (rho=.595), functional (rho=.632), and balance (rho=.666) scores. The prevalence of PB was not influenced by the side of the lesion. A limitation of the study was that the reliability of the clinical examination method was not investigated.

DISCUSSION AND CONCLUSION

The results support the validity of the SCP and suggest the need to choose different SCP cutoff criteria (Crit_2 or Crit_3) according to the aim of the evaluation.

Measuring trunk orientation with a CMOS camera: feasibility and accuracy

The purpose of this study was to develop and validate a new tool to objectively quantify trunk orientation at the bedside, especially dedicated to the measurement of the lateropulsion in acute and subacute stroke patients. We developed software to analyze 2D movement with a CMOS camera (Logitech Quickcam Pro 4000) and to calculate the orientation of a segment defined by two color markers. First, the accuracy, reproducibility and noise when measuring segment orientations were evaluated with the CMOS camera placed in different positions, and second trunk orientation was measured in static and in dynamic conditions both with a CMOS camera and with a gold standard 3D video system (BTS SMART-e). Results showed that the measurement was accurate (mean error=0.05+/-0.12 degrees), reproducible (S.D. over five measurements=0.005 degrees ) and steady (noise signal=0.02 degrees ). The data obtained with the CMOS camera were highly correlated with those obtained with the 3D video system both in static and in dynamic conditions. However, the CMOS camera must be relatively well centered on the measured segment to avoid error due to image distortion. The parallax error was negligible. In conclusion, this could be an important step in the postural assessment of acute and subacute stroke patients. The CMOS camera, a simple, portable, compact, low-cost, commercially available apparatus is the first tool to objectively quantify lateropulsion at the bedside. This method could also support the development of a rehabilitation program for trunk orientation based on biofeedback using the real-time signal provided by the device.

Pusher syndrome--a frequent but little-known disturbance of body orientation perception

Disturbances of body orientation perception after brain lesions may specifically relate to only one dimension of space. Stroke patients with "pusher syndrome" suffer from a severe misperception of their body's orientation in the coronal (roll) plane. They experience their body as oriented 'upright' when it is in fact markedly tilted to one side. The patients use the unaffected arm or leg to actively push away from the un-paralyzed side and resist any attempt to passively correct their tilted body posture. Although pusher patients are unable to correctly determine when their own body is oriented in an upright, vertical position, they seem to have no significant difficulty in determining the orientation of the surrounding visual world in relation to their own body. Pusher syndrome is a distinctive clinical disorder occurring characteristically after unilateral left or right brain lesions in the posterior thalamus and -less frequently- in the insula and postcentral gyrus. These structures thus seem to constitute crucial neural substrates controlling human (upright) body orientation in the coronal (roll) plane. A further disturbance of body orientation that predominantly affects a single dimension of space, namely the transverse (yaw) plane, is observed in stroke patients with spatial neglect. Apparently, our brain has evolved separate neural subsystems for perceiving and controlling body orientation in different dimensions of space.

Vers une meilleure compréhension et une évaluation quantifiée du « pushing », un comportement postural dû à certains AVC

INTRODUCTION

Postural control aims to build up and align the body orientation (posture) and stabilize body segments. The existence of two separate mechanisms, one for the control of body orientation with respect to gravity and one for its stabilisation, is an emerging concept that allows a better understanding of postural disorders, including pushing, after stroke. Objectives. - Literature review concerning pushing, one of the most puzzling postural behaviours after stroke.

METHODS

Critical review of papers indexed in Medline and book chapters dealing with pushing.

RESULTS

There is no agreement about the definition of pushing: some authors consider that pushers push himself toward the paretic side using the healthy arm or leg; others consider that pushers lean (list) toward the side opposite the lesion and resist any attempt to become more upright. Surprisingly, the push itself has never been measured. Some ordinal scales have been recently proposed, but their psychometric properties have not been analysed. These methodological insufficiencies explain in part the disagreements about frequency (from 5% to 50% of patients with stroke) and cause(s) of pushing.

CONCLUSION

Pushing may be the most dramatic clinical manifestations of an extreme bias in the construction of the biological vertical. We argue for a better assessment of vertical perception/representation after stroke involving the three modalities of the biological (subjective) vertical: the visual vertical, the haptic or tactile vertical, and especially the postural vertical.