Lesion Localization of Poststroke Lateropulsion.

Background and Purpose- Hemispheric stroke studies associating lateropulsion (pusher syndrome) with the location of brain lesions have had mixed results from small, unmatched samples. This study was designed to determine whether lateropulsion localizes to specific brain regions across patients with stroke using a case-control design. Methods- Fifty patients with lateropulsion after stroke were matched with 50 stroke patients without lateropulsion using age, time since onset of stroke, admission motor Functional Independence Measure score, lesion side, and gender. The primary analysis included multivariate lesion symptom mapping using sparse canonical correlations to identify regions most associated with lateropulsion as assessed with the Burke Lateropulsion Scale. Secondary analyses included evaluating paired comparisons for lesion volume, degree of motor impairment, motor and cognitive Functional Independence Measure scores. Results- The lesion symptom mapping analysis of all lesions mapped onto a common hemisphere produced an overall significant model ( P<5×10-5) with a regional peak at the inferior parietal lobe at the junction of the post-central gyrus (Brodmann Area 2) and Brodmann Area 40 as the lesion location most associated with lateropulsion. Lesion volume was larger for patients with lateropulsion. Despite adequate matching, motor performance and total Functional Independence Measure scores differed at a group level between patients with and without lateropulsion. Conclusions- This analysis implicated lesion involvement of the inferior parietal lobe as a key neuroanatomical determinant of developing lateropulsion. A better understanding of the anatomic underpinnings of lateropulsion may improve rehabilitation efforts, including the potential for informing noninvasive neuromodulation approaches.

Case-Control Study of Impairments Associated with Recovery from "Pusher Syndrome" after Stroke: Logistic Regression Analyses.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Electromyographic Analyses of Trunk Musculature after Stroke: An Integrative Review.

BACKGROUND: Observational and intervention studies examining trunk electromyographic (EMG) activity following stroke are underpowered and fail criteria for systematic reviews of randomized control trials. Objective: To systematically evaluate and summarize evidence about trunk muscle activation after stroke during ADL and with diagnostic and therapeutic interventions. METHODS: Search databases were Medline Complete, CINAHL and Health Sources: Nursing Academic Edition. Studies written in English after 1989 included these search terms: stroke, muscle activity, and trunk including abdominal or back muscles. Systematic reviews, single case studies, dissertations, or letters to the editor were excluded. Reviewers used Covidence to screen relevant research and extract information after title, abstract, and full-text screening. Information extracted related to stroke severity, time since onset, specific muscles and EMG analysis technique, and study limitations. Articles were classified as observational, intervention or device-related. RESULTS: The electronic search yielded 188 articles and a hand search found 3. Title and abstract screening yielded 102 articles for full text screening. Ultimately, 45 articles were extracted. Trunk muscle recruitment during function and movement demonstrated significant differences in trunk EMG recruitment timing, magnitude, and symmetry after stroke when compared with healthy participants. Individuals with stroke demonstrated significant differences when comparing paretic to non-paretic side trunk EMG measures. Intervention studies showed some effect on improving trunk muscle activation but they had small sample sizes and methodological issues. CONCLUSIONS: Trunk muscle activation after stroke can be monitored with EMG during rehabilitation programs which challenge functional recovery.

Clinical examination tools for lateropulsion or pusher syndrome following stroke: a systematic review of the literature.

OBJECTIVE: To examine the clinimetric properties and clinical applicability of published tools for 'quantifying' the degree of lateropulsion or pusher syndrome following stroke. DATA SOURCES: Search through electronic databases (MEDLINE, EMBASE, CINAHL, Science Citation Index) with the terms lateropulsion, pushing, pusher syndrome, validity, reliability, internal consistency, responsiveness, sensitivity, specificity, posture and stroke. Databases were searched from their inception to October 2008. REVIEW METHODS: Abstracts were selected by one author. A panel of experts then determined which should be included in this review. Five abstracts were reviewed and the panel agreed to omit one abstract because those authors did not write a full manuscript. The panel critiqued manuscripts according to predetermined criteria about clinical and clinimetric properties. RESULTS: Four manuscripts referencing three tools for examining lateropulsion were found. Validity and reliability data support the clinical use of the Scale for Contraversive Pushing, the Modified Scale for Contraversive Pushing and the Burke Lateropulsion Scale. The Scale for Contraversive Pushing has the most extensive testing of clinimetric properties. The other tools show promising preliminary evidence of clinical and research utility. More testing is needed with larger, more diverse samples. REVIEWERS' CONCLUSIONS: The Scale for Contraversive Pushing, the Modified Scale for Contraversive Pushing and the Burke Lateropulsion Scale are reliable and valid measures with good clinical applicability. Larger, more varied samples should be used to better delineate responsiveness and other clinimetric properties of these examination tools.

Outcomes with stroke and lateropulsion: a case-matched controlled study.

BACKGROUND AND OBJECTIVE: Lateropulsion after stroke has not been tracked using a case-matched controlled study and a standardized lateropulsion scale. Matched pairs of patients with stroke, with and without lateropulsion, were compared for functional outcomes and discharge destination following inpatient rehabilitation. METHODS: A retrospective chart review of patients with ischemic stroke at an inpatient rehabilitation hospital matched 36 pairs of patients with versus without lateropulsion. Scores of 2 or greater on the Burke Lateropulsion Scale identified lateropulsion. Matching criteria were side of stroke, sex, age, admission motor Functional Independence Measure (FIM), and interval poststroke. FIM efficiency (change in total FIM/length of stay) and discharge destination were analyzed with Wilcoxon signed-ranks tests. RESULTS: FIM efficiency and discharge FIM scores were lower in the lateropulsion group. Groups had similar mean lengths of stay. Post-hoc analyses showed that only patients with lateropulsion and right brain damage had significantly different FIM efficiency and discharge FIM scores. Lower extremity weakness was greater in the lateropulsion group at discharge; patients with right brain damage accounted for this difference. Patients with lateropulsion required more dependent living situations at discharge, especially if they had right brain damage. CONCLUSIONS: Patients with lateropulsion following stroke have a lower FIM efficiency and more dependency at discharge when compared with matched controls with equal functional limitations. Secondary analyses show worse outcomes for the subgroup of patients with right hemisphere stroke; lateropulsion and greater leg weakness may account for differences. Patients with lateropulsion may require longer rehabilitation to reach outcome goals.

Surface electromyography of lumbar paraspinal muscles during seated passive tilting of patients with lateropulsion following stroke.

BACKGROUND: Patients with lateropulsion (pushing) following stroke push toward the contralesional side. Their response to a passive tilt while seated has not been studied with surface electromyography (sEMG) of lumbar paraspinal muscles. OBJECTIVE: To compare onset, response duration, and trends in lumbar paraspinal muscle activity among patients with stroke, patients with stroke and lateropulsion, and healthy controls during seated passive tilting. METHOD: Seated subjects were passively tilted in the frontal plane at slow and fast speeds. Bilateral sEMG electrodes at the level of lumbar vertebrae 3 recorded paraspinal muscle activity. Surface EMG onset, response duration, and type of muscle activity were compared for 15 patients with stroke and lateropulsion, 12 patients with uncomplicated stroke, and 16 healthy, aged controls. Correlations were assessed between the Burke Lateropulsion Scale (BLS) and both sEMG onset and sEMG response duration. RESULTS: Onset of muscle activity was similar in all groups. Patients with lateropulsion showed decreased sEMG response duration in weak-sided paraspinal muscle activity during slow, passive tilting to the strong side. They had more variable muscle activity during fast, passive tilting to the weak side than controls. BLS scores did not correlate with dependent variables. CONCLUSIONS: Patients with lateropulsion activated paraspinal muscles with similar onset time as controls during seated passive tilting. Lateropulsion influences weak-sided paraspinal response duration during passive tilting. Graviceptive neglect may explain some of this difficulty with sustaining contractions, but weakness may also be a contributing factor.

Polarity-Dependent Misperception of Subjective Visual Vertical during and after Transcranial Direct Current Stimulation (tDCS).

Pathologic tilt of subjective visual vertical (SVV) frequently has adverse functional consequences for patients with stroke and vestibular disorders. Repetitive transcranial magnetic stimulation (rTMS) of the supramarginal gyrus can produce a transitory tilt on SVV in healthy subjects. However, the effect of transcranial direct current stimulation (tDCS) on SVV has never been systematically studied. We investigated whether bilateral tDCS over the temporal-parietal region could result in both online and offline SVV misperception in healthy subjects. In a randomized, sham-controlled, single-blind crossover pilot study, thirteen healthy subjects performed tests of SVV before, during and after the tDCS applied over the temporal-parietal region in three conditions used on different days: right anode/left cathode; right cathode/left anode; and sham. Subjects were blind to the tDCS conditions. Montage-specific current flow patterns were investigated using computational models. SVV was significantly displaced towards the anode during both active stimulation conditions when compared to sham condition. Immediately after both active conditions, there were rebound effects. Longer lasting after-effects towards the anode occurred only in the right cathode/left anode condition. Current flow models predicted the stimulation of temporal-parietal regions under the electrodes and deep clusters in the posterior limb of the internal capsule. The present findings indicate that tDCS over the temporal-parietal region can significantly alter human SVV perception. This tDCS approach may be a potential clinical tool for the treatment of SVV misperception in neurological patients.

Time to recovery from lateropulsion dependent on key stroke deficits: a retrospective analysis.

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.

Physical therapy students' self-reports of development of clinical reasoning: a preliminary study.

Reports of student perceptions about the efficacy of educational tools used by academic and clinical instructors to facilitate clinical reasoning are limited. Physical therapist students' (PTSs') perceptions of tools for developing clinical reasoning and problem-solving skills were surveyed to determine the effectiveness of various teaching methods and to identify factors associated with clinical reasoning development. The purposes of this descriptive investigation were to determine (1) if factors, such as learning mode, life experience, and curriculum, influence PTS' perception of their clinical reasoning mastery; (2) the relative roles of academic and clinical instructors and the value of their pedagogic tools in assisting PTS with clinical reasoning development; and (3) how PTS rate their degree of mastery of clinical reasoning as they progress through training. A survey was mailed to 17 physical therapy schools in New York and 2 in New Jersey; 156 PTS near graduation responded, yielding a 22% response rate. The survey instrument had 6 open-ended and 19 multiple-choice questions. Frequency analysis showed (1) PTS' opinion about how they would teach clinical reasoning varied with their preferred learning mode, (2) prior life experiences were associated with clinical reasoning for some individuals, (3) academic and clinical instructors contribute to development of clinical reasoning, (4) the best pedagogic tools involved case study presentations/ assignments using actual patients or videotapes, and (5) PTS gained confidence in their clinical reasoning ability while progressing through clinical education experiences. Results support inclusion of diverse pedagogic tools, such as case studies, and emphasizing a variety of learning modes to facilitate PTS' development of clinical reasoning.

Pedagogical tools to develop clinical reasoning: physical therapy students' perspective.

Physical therapy students' perspective about the development of clinical decision making ability was solicited to determine: 1) if actual clinical and academic learning experiences are consistent with student preferences; and 2) if actual academic learning experiences differ according to subject matter. Program representatives contacted physical therapy students via email with an embedded link to an on-line survey during their final clinical education experiences. Open-ended and forced-choice items addressed reactions to learning experiences to develop clinical reasoning in academic and final clinical education experiences. Data were analyzed with frequency analysis, chi-square and correlations of survey items. Ninety-one respondents completed the survey, yielding a 13% response rate. The frequency of use of pedagogical tools was lower than the preferred use of the tools. Perceptions about clinical reasoning learning tools varied with course content. Course content corresponded to the type of pedagogical tool that students deemed essential for learning clinical reasoning. Participants appeared to experience and prefer more independence at the final clinical experience although they preferred considerable involvement by the clinical instructor.