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Dive into the research topics where Cynthia J. Danells is active.

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Featured researches published by Cynthia J. Danells.


Neurorehabilitation and Neural Repair | 2002

The fugl-meyer assessment of motor recovery after stroke: a critical review of its measurement properties.

David J. Gladstone; Cynthia J. Danells; Sandra E. Black

Measurement of recovery after stroke is becoming increasingly important with the advent of new treatment options under investigation in stroke rehabilitation research. The Fugl-Meyer scale was developed as the first quantitative evaluative instrument for measuring sensorimotor stroke recovery, based on Twitchell and Brunnstrom’s concept of sequential stages of motor return in the hemiplegic stroke patient. The Fugl-Meyer is a well-designed, feasible and efficient clinical examination method that has been tested widely in the stroke population. Its primary value is the 100-point motor domain, which has received the most extensive evaluation. Excellent interrater and intrarater reliability and construct validity have been demonstrated, and preliminary evidence suggests that the Fugl-Meyer assessment is responsive to change. Limitations of the motor domain include a ceiling effect, omission of some potentially relevant items, and weighting of the arm more than the leg. Further study should test performance of this scale in specific subgroups of stroke patients and better define its criterion validity, sensitivity to change, and minimal clinically important difference. Based on the available evidence, the Fugl-Meyer motor scale is recommended highly as a clinical and research tool for evaluating changes in motor impairment following stroke.


Stroke | 2006

Physiotherapy Coupled With Dextroamphetamine for Rehabilitation After Hemiparetic Stroke A Randomized, Double-Blind, Placebo-Controlled Trial

David J. Gladstone; Cynthia J. Danells; Armi Armesto; William E. McIlroy; W. Richard Staines; Simon J. Graham; Nathan Herrmann; John P. Szalai; Sandra E. Black

Background and Purpose— Hemiparesis is the commonest disabling deficit caused by stroke. In animals, dextroamphetamine (AMPH) paired with training enhances motor recovery, but its clinical efficacy is uncertain. Methods— In a randomized, double-blind, placebo-controlled trial, 71 stroke patients were stratified by hemiparesis severity and randomly assigned to 10 sessions of physiotherapy coupled with either 10 mg AMPH or placebo. Study treatments were administered by 1 physiotherapist, beginning 5 to 10 days after stroke and continuing twice per week for 5 weeks. Outcomes were assessed by 1 physiotherapist at baseline, after each treatment session, at 6 weeks, and at 3 months. The primary outcome was motor recovery (impairment level) on the Fugl-Meyer (FM) scale. Secondary outcomes assessed mobility, ambulation, arm/hand function, and independence in activities of daily living. Results— Baseline hemiparesis was severe overall (mean FM score 27.7±20.0). Motor scores improved during treatment in both groups (mean change, baseline to 3 months 29.5±16.6). Repeated-measures ANOVA revealed no significant differences in recovery between the treatment groups for the entire cohort (n=67) or for subgroups with a severe hemiparesis (n=43), moderate hemiparesis (n=24), or cortically based stroke (n=26). In the moderate subgroup, there was a significant drug×time interaction for upper extremity motor recovery (F=5.14; P<0.001), although there was a significant baseline imbalance in motor scores in this subgroup. Conclusion— In stroke patients with a severe motor deficit, 10 mg AMPH coupled with physiotherapy twice per week for 5 weeks in the early poststroke period provided no additional benefit in motor or functional recovery compared with physiotherapy alone. Patients with moderate severity hemiparesis deserve further investigation. Increased intensity and longer duration drug/therapy dosing regimens should be explored, targeting the upper and lower limbs separately.


Stroke | 2009

Association Between Gait Asymmetry and Brain Lesion Location in Stroke Patients

Lisa D. Alexander; Sandra E. Black; Kara K. Patterson; Fuqiang Gao; Cynthia J. Danells; William E. McIlroy

Background and Purpose— Associations between the site of brain injury and poststroke gait impairment are poorly understood. Temporal gait asymmetry after stroke is a salient index of gait dysfunction that has important functional consequences. The current study investigated whether subtraction lesion analysis could distinguish brain regions associated with persisting temporal gait asymmetry in chronic stroke patients. Methods— Analysis was conducted on 37 chronic ambulatory stroke patients (17 symmetrical gait, 20 asymmetrical gait). Spatiotemporal gait parameters were recorded using an instrumented walking surface. Lesions were traced from 3D T1-MRI, and region of interest images were generated. The lesion overlay of patients with symmetrical gait was subtracted from patients with asymmetrical gait to highlight voxels more frequently lesioned in asymmetrical patients and relatively spared in symmetrical patients. Results— Demographic data were comparable between the 2 groups. Asymmetrical patients exhibited significantly higher National Institute of Health Stroke Scale neglect scores and more severe motor impairment. Gait asymmetry was significantly correlated to Chedoke-McMaster Stroke Scale leg (r=−0.767, P<0.001) and foot (r=−0.759, P<0.001) scores, whereas gait speed correlated less strongly. After subtraction analysis, injury to the posterolateral putamen was evident 60% to 80% more frequently in the asymmetrical group compared to the symmetrical group. Conclusions— In this sample of ambulatory chronic stroke patients, damage to the posterolateral putamen was associated with temporal gait asymmetry. Further advances in our understanding of the neural correlates of gait asymmetry may provide prognostic markers for future persistent gait dysfunction and lead to early targeted rehabilitation when key regions are damaged.


Stroke | 2004

Poststroke “Pushing”: Natural History and Relationship to Motor and Functional Recovery

Cynthia J. Danells; Sandra E. Black; David J. Gladstone; William E. McIlroy

Background and Purpose— Patients with hemiparetic stroke have impaired balance control. Some patients (“pushers”) are resistant to accepting weight on and actively “push” away from the nonparetic side. This research identified pushers from stroke patients with moderate to severe hemiparesis and examined longitudinal changes in symptoms, level of impairment, and functional independence. Methods— Prospective sample of hemiparetic stroke patients (n=65) located in Toronto, Canada. Detailed clinical assessments were performed within 10 days postonset, at 6 weeks, and at 3 months. Results— At 1 week after stroke, 63% of patients demonstrated features of pushing. In 62% of pushers, symptoms resolved by 6 weeks, whereas in 21%, pushing symptoms persisted at 3 months. Motor recovery and functional abilities at 3 months were significantly lower among the pushers compared with the nonpushers. Pushers also had a significantly longer hospital length of stay (89 days versus 57 days). It is noteworthy that motor and functional recovery improved significantly over the 3-month study period for both pushers and nonpushers. Conclusions— Identification of stroke patients with pushing symptoms has prognostic implications for recovery. In light of this potential recovery, rehabilitation specialists need to refine treatment approaches for the pushers to further improve functional outcome.


Clinical Biomechanics | 2011

Between-limb synchronization for control of standing balance in individuals with stroke

Avril Mansfield; Cynthia J. Danells; Elizabeth L. Inness; George Mochizuki; William E. McIlroy

BACKGROUND During standing, forces and moments exerted at the feet serve to maintain stability in the face of constant centre-of-mass movement. These actions are temporally synchronized in healthy individuals. Stroke is typically a unilateral injury resulting in increased sensori-motor impairment in the contra-lesional compared with the ipsi-lesional lower-limb, which could lead to reduced between-limb synchronization for control of standing balance. The purpose of this study is to investigate between-limb synchronization of standing balance control in individuals with stroke; a potentially important index of control of upright stability. METHODS Twenty healthy controls and 33 individuals with unilateral stroke were assessed. Stability was assessed during a 30-second quiet standing trial by measuring data from two force plates (one per foot). Limb-specific centre of pressure was calculated. Between-limb synchronization was defined as the coefficient of the correlation between the left and right foot for both the antero-posterior and medio-lateral centre of pressure time series. Synchronization, weight-bearing symmetry, and root mean square of the total centre of pressure excursion were compared between controls and stroke participants. FINDINGS Stroke participants swayed more, were more asymmetric, and had less between-limb synchronization than healthy controls. Among individuals with stroke, reduced between-limb synchronization was related to increased postural sway in the medio-lateral direction and increased weight-bearing asymmetry. INTERPRETATION Individuals with stroke have reduced temporal synchronization of centre of pressure fluctuations under the feet when controlling quiet standing. The clinical significance of reduced synchronization remains to be determined, although it appears linked to increased medio-lateral sway and weight-bearing asymmetry.


Gait & Posture | 2013

Determinants and consequences for standing balance of spontaneous weight-bearing on the paretic side among individuals with chronic stroke.

Avril Mansfield; Cynthia J. Danells; John L. Zettel; Sandra E. Black; William E. McIlroy

Hemiparetic stroke patients commonly bear more weight on the non-paretic side which seems intuitively linked to unilateral control deficits. However, there is evidence that some post-stroke favour weighting the paretic side, which may be problematic given altered capacity of the paretic limb to contribute to the control of upright posture. This study explores the prevalence and clinical determinants of stance asymmetry, and the relationship between stance asymmetry and postural control among chronic stroke patients. Subjects (n=147; >6 months post-stroke) stood on two force plates in eyes-open and eyes-closed conditions; 59 were symmetric, 18 had paretic asymmetry (PA), and 70 had non-paretic asymmetry (NPA). Root mean square (RMS) of antero-posterior and medio-lateral centre-of-pressure under each limb and both limbs combined were compared. RMS of total medio-lateral centre-of-pressure was greater for both asymmetric groups compared with the symmetric group. PA subjects relied less on the loaded limb for control than NPA subjects and relied more on visual information for postural control than those who were symmetric. There were no differences in the characteristics of individuals between the PA and NPA groups. The loading of the paretic limb was not related to impaired postural control during stationary standing which was attributable, in part, to individuals relying on control from the non-paretic limb, in spite of lower vertical load, and a greater dependence on visual contributions. There was no evidence that greater loading on the paretic limb was related to persisting dyscontrol but may rather reflect a learned strategy.


NeuroRehabilitation | 2014

Frequency of domain-specific cognitive impairment in sub-acute and chronic stroke.

Laura E. Middleton; Benjamin Lam; Halla Fahmi; Sandra E. Black; William E. McIlroy; Donald T. Stuss; Cynthia J. Danells; Jon Erik Ween; Gary R. Turner

BACKGROUND Functional contributions of cognitive impairment may vary by domain and severity. OBJECTIVE (1) To characterize frequency of cognitive impairment by domain after stroke by severity (mild: -1.5 ≤ z-score < -2; severe: Z ≤ -2) and time (sub-acute: < 90d; chronic: 90d-2yrs); and (2) To assess the association of cognitive impairment with function in chronic stroke. METHODS Cognitive function was characterized among 215 people with sub-acute or chronic stroke (66.8 years, 43.3% female). Z-scores by cognitive domain were determined from normative data. Function was defined as the number of IADLs minimally independent. RESULTS 76.3% of sub-acute and 67.3% of chronic stroke participants had cognitive impairment in ≥ 1 domain (p-for-difference = 0.09). Severe impairment was most common in psychomotor speed (sub-acute: 53.5%; chronic: 33.7%). Impairment in executive function was common (sub-acute: 39.5%; chronic: 30.7%) but was usually mild. Severe impairment in psychomotor speed, visuospatial function, and language and any impairment in executive function and memory was associated with IADL impairment (p < 0.03). CONCLUSIONS Mild cognitive impairment is common after stroke but is not associated with functional disability. Impairment in psychomotor speed, executive function, and visuospatial function is common and associated with functional impairment so should be a focus of screening and rehabilitation post-stroke.


Clinical Biomechanics | 2013

The effect of post-stroke lower-limb spasticity on the control of standing balance: Inter-limb spatial and temporal synchronisation of centres of pressure

Jonathan C. Singer; Avril Mansfield; Cynthia J. Danells; William E. McIlroy; George Mochizuki

BACKGROUND Challenges in stability control are common post-stroke. Although lower-limb spasticity is a common sensorimotor consequence post-stroke, its potential to further complicate stability control among stroke-survivors remains largely unknown. Advancing such understanding can help inform strategies to reduce fall risk and increase independence among these individuals. The purpose of this study was to characterise the extent of limb-specific dyscontrol among individuals with spasticity. METHODS A retrospective analysis of 131 patients assessed for spasticity was performed. Patients selected for inclusion were categorised into two groups, with (n=19) or without (n=63) unilateral lower-limb spasticity. Two force platforms were used to determine the individual-limb and net centres of pressure in both anteroposterior and mediolateral directions during 30s of quiet standing. Limb-specific dyscontrol was assessed by calculating weight-bearing symmetry ratios, cross-correlation coefficients at zero phase-shift (temporal synchrony) and ratios of individual-limb root-mean-square displacements (spatial symmetry). Total body postural control was assessed by examining the root-mean-square of the net centre of pressure displacement. FINDINGS The group with spasticity bore less weight on the affected limb and exhibited reduced temporal synchrony of centre of pressure displacements. There were no differences in inter-limb root-mean-square centre of pressure ratios or in the root-mean-square of the net centre of pressure displacement. INTERPRETATION Individuals with lower-limb spasticity may have additional challenges with stability control, specifically linked to the ability to modify the location of the centre of pressure beneath the affected limb, in a time-sensitive manner so as to contribute beneficially to the control of whole body stability.


Journal of Stroke & Cerebrovascular Diseases | 2017

Does Perturbation Training Prevent Falls after Discharge from Stroke Rehabilitation? A Prospective Cohort Study with Historical Control

Avril Mansfield; Alison Schinkel-Ivy; Cynthia J. Danells; Anthony Aqui; Raabeae Aryan; Louis Biasin; Vincent G. DePaul; Elizabeth L. Inness

BACKGROUND Individuals with stroke fall frequently, and no exercise intervention has been shown to prevent falls post stroke. Perturbation-based balance training (PBT), which involves practicing reactions to instability, shows promise for preventing falls in older adults and individuals with Parkinsons disease. This study aimed to determine if PBT during inpatient stroke rehabilitation can prevent falls after discharge into the community. METHODS Individuals with subacute stroke completed PBT as part of routine inpatient rehabilitation (n = 31). Participants reported falls experienced in daily life for up to 6 months post discharge. Fall rates were compared to a matched historical control group (HIS) who did not complete PBT during inpatient rehabilitation. RESULTS Five of 31 PBT participants, compared to 15 of 31 HIS participants, reported at least 1 fall. PBT participants reported 10 falls (.84 falls per person per year) whereas HIS participants reported 31 falls (2.0 falls per person per year). When controlled for follow-up duration and motor impairment, fall rates were lower in the PBT group than the HIS group (rate ratio: .36 [.15, .79]; P = .016). CONCLUSIONS These findings suggest that PBT is promising for reducing falls post stroke. While this was not a randomized controlled trial, this study may provide sufficient evidence for implementing PBT in stroke rehabilitation practice.


Journal of Stroke & Cerebrovascular Diseases | 2016

Feasibility and Effects of Cardiac Rehabilitation for Individuals after Transient Ischemic Attack

Susan Marzolini; Cynthia J. Danells; Paul Oh; David Jagroop; Dina Brooks

BACKGROUND AND OBJECTIVE Cardiac rehabilitation programs (CRPs) are common for cardiac patients; however, most individuals post transient ischemic attack (TIA) receive no rehabilitation despite similar pathologies. The objective of this study is to determine effects of cardiac rehabilitation (CR) on cardiovascular fitness (peak oxygen uptake [VO2peak]) and 6-minute walk distance (6MWD) post TIA. Secondary outcomes included other clinical and process indicators. METHODS Eighty-five people post TIA (mean age 67.5 ± 10.7, 47% female) were referred to CR (2006-2014). The retro-TIA cohort included 65 consecutively enrolled individuals who were evaluated retrospectively. To collect additional measures, the pro-TIA cohort included 20 participants who were followed prospectively with a 3-month nonintervention period followed by 6-months of CR with 6MWD, cognition, depression score, and anthropometrics measured at each time point. Baseline, 6-month cardiopulmonary exercise test results, depression score, and anthropometrics were examined separately for both cohorts. RESULTS Among all participants, 62% completed CR with 72.8 ± 17.7% attendance to prescheduled classes. CR resulted in improvements in VO2peak for both cohorts (both, P < .02). In the retro-TIA cohort, there were improvements in resting heart rate and body mass index, with reductions in the proportion of people with obesity and abdominal obesity (all, P < .04). In the pro-TIA cohort, compared to the stable baseline period there was a significant improvement with the CR intervention in the depression score (Δ1.1 ± 4.3 and Δ-3.3 ± 3.9, respectively; P = .04) but not in 6MWD (Δ4.8 ± 42 m and Δ61.0 ± 73.5 m, respectively; P = .06). For all participants, regression analysis revealed a higher depression score (β = 1.10, P = .02), male sex (β = 4.932, P = .02), and less social support (β = 4.085, P = .04) as predictors of dropout. CONCLUSIONS A CRP is feasible and effective for improving cardiovascular health. Strategies to promote adherence in men, in those with depressive symptoms, and in those with less social support require investigation.

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Avril Mansfield

Toronto Rehabilitation Institute

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Sandra E. Black

Sunnybrook Health Sciences Centre

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Anthony Aqui

Toronto Rehabilitation Institute

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Louis Biasin

Toronto Rehabilitation Institute

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Mark Bayley

Toronto Rehabilitation Institute

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