Andrea L Behrman

University of Florida, Gainesville, Florida, United States

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Publications (90)266 Total impact

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    ABSTRACT: The Locomotor Experience Applied Post Stroke rehabilitation trial found equivalent walking outcomes for body weight-supported treadmill plus overground walking practice versus home-based exercise that did not emphasize walking. From this large database, we examined several clinically important questions that provide insights into recovery of walking that may affect future trial designs. Using logistic regression analyses, we examined predictors of response based on a variety of walking speed-related outcomes and measures that captured disability, physical impairment, and quality of life. The most robust predictor was being closer at baseline to the primary outcome measure, which was the functional walking speed thresholds of 0.4 m/s (household walking) and 0.8 m/s (community walking). Regardless of baseline walking speed, a younger age and higher Berg Balance Scale score were relative predictors of responding, whether operationally defined by transitioning beyond each speed boundary or by a continuous change or a greater than median increase in walking speed. Of note, the cutoff values of 0.4 and 0.8 m/s had no particular significance compared with other walking speed changes despite their general use as descriptors of functional levels of walking. No evidence was found for any difference in predictors based on treatment group.
    The Journal of Rehabilitation Research and Development 04/2014; 51(1):39-50. · 1.78 Impact Factor
  • Preeti M. Nair, Chetan P. Phadke, Andrea L. Behrman
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    ABSTRACT: Objective To examine the dynamic modulation of the soleus H-reflex while walking with a posterior leaf spring ankle foot orthosis (PAFO). Methods Soleus H-reflexes were evoked on randomly chosen lower limb of fourteen healthy individuals (age range of 22-36 years, 7 women) while walking on a treadmill with and without a PAFO. In order to capture excitability across the duration of the gait cycle, H-reflexes were evoked at heel strike (HS), HS + 100ms, HS + 200ms, HS + 300ms, HS + 400ms in the stance phase and at toe-off (TO), TO + 100ms, TO + 200ms, TO + 300ms, TO + 400ms in the swing phase respectively. Results H-reflex excitability was significantly higher in the form of greater slope of the rise in H-reflex amplitude across the swing phase (p = 0.024) and greater mean H-reflex amplitude (p = 0.014) in the swing phase of walking with a PAFO. There was no change in the slope (p = 0.25) or the mean amplitude of H-reflexes (p = 0.22) in the stance phase of walking with a PAFO. Mean background EMG activity between the two walking conditions was not significantly different for both the tibialis anterior (p = 0.69) and soleus muscles (p = 0.59). Conclusion PAFO increased reflex excitability in the swing phase of walking in healthy individuals. Altered sensory input originating from joint, muscle and cutaneous receptors may be the underlying mechanism for greater reflex excitability. The neurophysiological effect of PAFOs on reflex modulation during walking needs to be tested in persons with neurological injury. The relationship between the sensory input and the reflex output during walking may assist in determining if there exists a neurological disadvantage of using a compensatory device such as a PAFO.
    Gait & posture 01/2014; · 2.58 Impact Factor
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    ABSTRACT: Rationale: Intermittent stimulation of the respiratory system with hypoxia causes persistent increases in respiratory motor output (i.e. long-term facilitation) in animals with spinal cord injury. This paradigm, therefore, has been touted as a potential respiratory rehabilitation strategy. Objectives: To determine if acute (daily) exposure to intermittent hypoxia can also evoke long-term facilitation of ventilation following chronic spinal cord injury in humans, and whether repeated daily exposure to intermittent hypoxia enhances the magnitude of this response. Methods: Eight individuals with incomplete spinal cord injury (>1 year; cervical (n=6), thoracic (n=2)) were exposed to intermittent hypoxia (eight 2-minute intervals of 8% oxygen) for 10 days. During all exposures, end-tidal carbon dioxide levels were maintained, on average, 2 mmHg above resting values. Minute ventilation, tidal volume, and breathing frequency were measured before (baseline), during, and 30 minutes following intermittent hypoxia. Sham protocols consisted of exposure to room air and were administered to a subset of the participants (n=4). Measurements and Main Results: Minute ventilation increased significantly for 30 minutes following acute exposure to intermittent hypoxia (p<0.001), but not following sham exposure. However, the magnitude of ventilatory long-term facilitation was not enhanced over 10 days of intermittent hypoxia exposures. Conclusions: Ventilatory long-term facilitation can be evoked by brief periods of hypoxia in humans with chronic spinal cord injury. Thus, intermittent hypoxia may represent a strategy for inducing respiratory neuroplasticity following declines in respiratory function that are related to neurological impairment.
    American Journal of Respiratory and Critical Care Medicine 11/2013; · 11.04 Impact Factor
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    ABSTRACT: The step activity monitor (SAM) quantifies steps taken in the home and community by patient populations. While the SAM has been used to study individuals post-stroke, compliance with SAM has not been addressed. Participants' compliance in wearing the monitor is critical for obtaining accurate assessments. The purpose of this study was to determine the rate of and predictors for inferred compliance with the SAM post-stroke. Cross-sectional. 408 community-dwelling individuals two-months post-stroke with moderate-to-severe gait impairment (gait speed of ≤ 0.8 m/s). Step activity was assessed for two days with the SAM. Inferred compliance was established in three periods: 6:00AM-12:00PM, 12:01PM-6:00PM, and 6:01PM-12:00AM. Compliance was defined as activity recorded in all three periods. The percentage of participant compliance for the first day, second day, both days, and either day was calculated. Demographic and clinical characteristics of compliers and non-compliers were compared. Independent compliance predictors were identified using stepwise logistic regression. Inferred compliance rate in the first day, second day, both days, and either day was 68, 61, 53, and 76%, respectively. Upper and lower extremity impairment, balance control and endurance were significantly different between compliers and non-compliers. On the other hand, older age, greater balance self-efficacy, and better walking endurance were found to be significant predictors of compliance. Participants consisted of individuals with sub-acute stroke. Therefore, our findings may not be generalized to individuals during the acute and chronic phases of stroke recovery. Strategies to improve compliance are needed, when collecting data for more than one day, and in samples with younger individuals, and persons with low levels of balance self-efficacy and walking endurance.
    Physical Therapy 09/2013; · 2.78 Impact Factor
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    ABSTRACT: In this article we explore how people with incomplete spinal cord injury (iSCI) create meaning out of their changing bodies as they undergo a therapeutic intervention called locomotor training (LT). Therapeutic interventions like LT are used to promote the recovery of walking ability among individuals with iSCI. The chronological nature of this study-interviews at three points throughout the 12-week intervention-enhances understanding of the recovering self after spinal cord injury. Drawing on a constructivist theoretical framework, we organize data according to three narrative frames. Participants interpreted LT as (a) a physical change that was meaningful because of its social significance, (b) a coping strategy for dealing with the uncertainty of long-term recovery, and (c) a moral strategy to reconstitute the self. We offer findings that lay the conceptual groundwork for generating new knowledge about what is important to people with iSCI as they relearn how to walk.
    Qualitative Health Research 06/2013; · 2.19 Impact Factor
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    ABSTRACT: A module is a functional unit of the nervous system that specifies functionally-relevant patterns of muscle activation. In adults, 4-5 modules account for muscle activation during walking. Neurologic injury alters modular control and is associated with walking impairments. The effect of neurologic injury on modular control in children is unknown and may differ from adults due to their immature and developing nervous systems. We examined modular control of locomotor tasks in children with incomplete spinal cord injuries (ISCIs) and control children. Five controls (8.6 ± 2.7 years) and five children with ISCIs (8.6 ± 3.7 years) performed treadmill walking, overground walking, pedaling, supine lower extremity flexion/extension, stair climbing, and crawling. Electromyograms (EMGs) were recorded in bilateral leg muscles. Non-negative matrix factorization was applied and the minimum number of modules required to achieve 90% of the "variance accounted for" (VAF) was calculated. On average, 3.5 modules explained muscle activation in the controls; whereas, 2.4 modules were required in the children with ISCIs. To determine if control is similar across tasks, the module weightings identified from treadmill walking were used to reconstruct the EMGs from each of the other tasks. This resulted in VAF values exceeding 86% for each child and each locomotor task. Our results suggest that 1) modularity is constrained in children with ISCIs; 2) for each child, similar neural control mechanisms are used across locomotor tasks. These findings suggest that interventions that activate the neuromuscular system to enhance walking also may influence the control of other locomotor tasks.
    Journal of Neurophysiology 06/2013; · 3.30 Impact Factor
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    ABSTRACT: Objectives To identify the clinical measures associated with improved walking speed after locomotor rehabilitation in individuals poststroke and how those who respond with clinically meaningful changes in walking speed differ from those with smaller speed increases.DesignA single group pre-post intervention study. Participants were stratified on the basis of a walking speed change of greater than (responders) or less than (nonresponders) .16m/s. Paired sample t tests were run to assess changes in each group, and correlations were run between the change in each variable and change in walking speed.SettingOutpatient interdisciplinary rehabilitation research center.ParticipantsHemiparetic subjects (N=27) (17 left hemiparesis; 19 men; age: 58.74±12.97y; 22.70±16.38mo poststroke).InterventionA 12-week locomotor intervention incorporating training on a treadmill with body weight support and manual trainers accompanied by training overground walking.Main Outcome MeasuresMeasures of motor control, balance, functional walking ability, and endurance were collected at pre- and postintervention assessments.ResultsEighteen responders and 9 nonresponders differed by age (responders=63.6y, nonresponders=49.0y, P=.001) and the lower extremity Fugl-Meyer Assessment score (responders=24.7, nonresponders=19.9, P=.003). Responders demonstrated an average improvement of .27m/s in walking speed as well as significant gains in all variables except daily step activity and paretic step ratio. Conversely, nonresponders demonstrated statistically significant improvements only in walking speed and endurance. However, the walking speed increase of .10m/s was not clinically meaningful. Change in walking speed was negatively correlated with changes in motor control in the nonresponder group, implying that walking speed gains may have been accomplished via compensatory mechanisms.Conclusions This study is a step toward discerning the underlying factors contributing to improved walking performance.
    Archives of physical medicine and rehabilitation 05/2013; 94(5):856–862. · 2.18 Impact Factor
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    ABSTRACT: OBJECTIVE: To assess the relationship between Exercise Tolerance Test (ETT) performance at 6-weeks post-stroke and subsequent performance in a treadmill and overground Locomotor Training Program (LTP). DESIGN: Prospective, cohort study. SETTING: Exercise testing laboratory in either a primary care hospital or outpatient clinic. PARTICIPANTS: Community-dwelling individuals (n= 469), 54.9±19.0 days post-stroke, enrolled in the Locomotor Experience Applied Post Stroke (LEAPS) randomized controlled trial. INTERVENTIONS: Not applicable MAIN OUTCOME MEASURES: For participants randomized to LTP, the number of sessions needed to attain the training goal of 20 minutes of treadmill stepping was determined. Regression analyses determined the contribution of ETT performance (cycling duration), age, and Six-Minute Walk Test (6MWT) distance to attainment of the stepping duration goal. RESULTS: Age, 6MWT and ETT performance individually accounted for 10.74%, 10.82% and 10.76%, respectively, of the variance in number of sessions needed to attain 20 minutes of stepping. When age and 6MWT were included in the model, the additional contribution of ETT performance was rendered non-significant (p=0.150). CONCLUSION: To the extent that ETT performance can be viewed as a measure of cardiovascular fitness rather than neurological impairment, cardiovascular fitness at the time of the ETT did not make a significant unique contribution to number of sessions needed to achieve 20 minutes stepping duration . The 6MWT, which involves less intensive exercise than the ETT and therefore likely to be predominantly affected by neurological impairment and muscular condition, appeared to account for as much variance as the ETT.
    Archives of physical medicine and rehabilitation 03/2013; · 2.18 Impact Factor
  • Andrea L Behrman, Mark G Bowden, Dorian K Rose
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    ABSTRACT: The clinical trial is essential to testing efficacy and effectiveness of therapeutic interventions. Neurorehabilitation presents unique challenges in the execution of clinical trials due to the complexity of both human interface with complex interventions and clinical/research staff interaction. Attention to key elements, recruitment, retention, treatment fidelity, and control intervention selection, contributes to successful conduct of a trial. Alternatives to the randomized controlled trial and outcome measure selection are important considerations contributing to the merit of the trial. While clinical trial outcomes contribute to the scientific evidence, their true value and impact comes in the next step, translation to clinical practice and the improvement of patient outcomes and qualify of life. Translation of evidence into practice may best be achieved via partnerships of scientists, clinicians, and administrators resulting in a dynamic interface between science and practice, the laboratory, and the clinic.
    Handbook of Clinical Neurology 01/2013; 110:61-6.
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    Andrea L Behrman, Shelley A Trimble
    Developmental Medicine & Child Neurology 10/2012; · 2.68 Impact Factor
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    ABSTRACT: To develop a scale (Neuromuscular Recovery Scale [NRS]) for classification of functional motor recovery after spinal cord injury (SCI) based on preinjury movement patterns that would reduce variability of the populations' level of function within each class, because assessment of functional improvement after SCI is problematic as a result of high variability of the populations' level of function and the insensitivity to change within the available outcome measures. Prospective observational cohort with longitudinal follow-up. Seven outpatient rehabilitation centers from the Christopher and Dana Reeve Foundation NeuroRecovery Network (NRN). Individuals (N=95) with American Spinal Injury Association Impairment Scale (AIS) grade C or AIS grade D having received at least 20 locomotor training treatment sessions in the NRN. Intensive locomotor training including stepping on a treadmill with partial body weight support and manual facilitation and translation of skills into home and community activities. Berg Balance Scale, six-minute walk test, and ten-meter walk test. Individuals classified within each of the 4 phases of the NRS were functionally discrete, as shown by significant differences in the mean values of balance, gait speed, and walking endurance, and the variability of these measurements was significantly reduced by NRS classification. The magnitude of improvements in these outcomes was also significantly different among phase groups. Assessment with the NRS provides a classification for functional motor recovery without compensation, which reduces variability in performance and improvements for individuals with injuries classified as AIS grades C and D.
    Archives of physical medicine and rehabilitation 09/2012; 93(9):1518-29. · 2.18 Impact Factor
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    ABSTRACT: Scientists, clinicians, administrators, individuals with spinal cord injury (SCI), and caregivers seek a common goal: to improve the outlook and general expectations of the adults and children living with neurologic injury. Important strides have already been accomplished; in fact, some have labeled the changes in neurologic rehabilitation a "paradigm shift." Not only do we recognize the potential of the damaged nervous system, but we also see that "recovery" can and should be valued and defined broadly. Quality-of-life measures and the individual's sense of accomplishment and well-being are now considered important factors. The ongoing challenge from research to clinical translation is the fine line between scientific uncertainty (ie, the tenet that nothing is ever proven) and the necessary burden of proof required by the clinical community. We review the current state of a specific SCI rehabilitation intervention (locomotor training), which has been shown to be efficacious although thoroughly debated, and summarize the findings from a multicenter collaboration, the Christopher and Dana Reeve Foundation's NeuroRecovery Network.
    Archives of physical medicine and rehabilitation 09/2012; 93(9):1588-97. · 2.18 Impact Factor
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    ABSTRACT: We present a retrospective case series of 2 individuals with motor-incomplete spinal cord injury (SCI) to examine differences in lifetime cost estimates before and after participation in an intensive locomotor training (LT) program. Sections of a life care plan (LCP) were used to determine the financial implications associated with equipment, home renovations, and transportation for patients who receive LT. An LCP is a viable method of quantifying outcomes following any therapeutic intervention. The LCP cases analyzed were a 61-year-old woman and a 4½-year-old boy with motor-incomplete SCI and impairments classified by the American Spinal Injury Association Impairment Scale (AIS) as AIS D and AIS C, respectively. Each patient received an intensive outpatient LT program 3 to 5 days per week. The 61-year-old woman received 198 sessions over 57 weeks and the 4½-year-old boy received 76 sessions over 16 weeks. The equipment, home renovation, and transportation costs of an LCP were calculated before and after LT. Prior to the implementation of LT, the 61-year-old woman had estimated lifetime costs between $150,247.00 and $199,654.00. Following LT, the estimated costs decreased to between $2010.00 and $2446.00 (a decrease of $148,237.00 and $197,208.00). Similarly, the 4-year-old boy had estimated lifetime costs for equipment, home renovation, and transportation between $535,050.00 and $771,665.00 prior to LT. However, the estimated costs decreased to between $97,260.00 and $200,047.00 (a decrease of $437,790.00 and $571,618.00) following LT. The lifetime financial costs associated with equipment, home renovations, and transportation following a motor-incomplete SCI were decreased following an intensive LT program for the 2 cases presented in this article. The LCP, including costs of rehabilitation and long-term medical and personal care costs, may be an effective tool to discern cost benefit of rehabilitation interventions.
    Journal of neurologic physical therapy: JNPT 07/2012; 36(3):144-53. · 1.65 Impact Factor
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    ABSTRACT: Harkema SJ, Schmidt-Read M, Lorenz D, Edgerton VR, Behrman AL. Balance and ambulation improvements in individuals with chronic incomplete SCI using locomotor training–based rehabilitation.
    Archives of physical medicine and rehabilitation 05/2012; 93(5):919-21. · 2.18 Impact Factor
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    ABSTRACT: To investigate the effect of walking speed on the emergence of locomotor electromyogram (EMG) patterns in an individual with chronic incomplete spinal cord injury (SCI), and to determine whether central pattern generator activity during robotic locomotor training (RLT) transfers to volitional EMG activity during overground walking. Single-case (B-A-B; experimental treatment-withdrawal-experimental treatment) design. Freestanding rehabilitation research center. A 50-year-old man who was nonambulatory for 16 months after incomplete SCI (sub-T11). The participant completed two 6-week blocks of RLT, training 4 times per week for 30 minutes per session at walking speeds up to 5km/h (1.4m/s) over continuous bouts lasting up to 17 minutes. Surface EMG was recorded weekly during RLT and overground walking. The Walking Index for Spinal Cord Injury (WISCI-II) was assessed daily during training blocks. During week 4, reciprocal, patterned EMG emerged during RLT. EMG amplitude modulation revealed a curvilinear relationship over the range of walking speeds from 1.5 to 5km/h (1.4m/s). Functionally, the participant improved from being nonambulatory (WISCI-II 1/20), to walking overground with reciprocal stepping using knee-ankle-foot orthoses and a walker (WISCI-II 9/20). EMG was also observed during overground walking. These functional gains were maintained greater than 4 years after locomotor training (LT). Here we report an unexpected course of locomotor recovery in an individual with chronic incomplete SCI. Through RLT at physiologic walking speeds, it was possible to activate the central pattern generator even 16 months postinjury. Further, to a certain degree, improvements from RLT transferred to overground walking. Our results suggest that LT-induced changes affect the central pattern generator and allow supraspinal inputs to engage residual spinal pathways.
    Archives of physical medicine and rehabilitation 03/2012; 93(8):1476-84. · 2.18 Impact Factor
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    ABSTRACT: Progress in locomotor rehabilitation has created an increasing need to understand the factors that contribute to motor behavior, to determine whether these factors are modifiable, and if so, to determine how best to modify them in a way that promotes improved function. Currently available clinical measures do not have the capacity to distinguish between neuromotor recovery and compensation for impaired underlying body structure/functions. This Special Interest article examines the state of outcomes measurement in physical therapy in regard to locomotor rehabilitation, and suggests approaches that may improve assessment of recovery and clinical decision-making capabilities. We examine historical approaches to measurement of locomotor rehabilitation outcomes, including rating scales, timed movement tasks, and laboratory-based outcome measures, and we discuss the emerging use of portable technology to assess walking in a free-living environment. The ability to accurately measure outcomes of rehabilitation, both in and away from the clinical/laboratory setting, allows assessment of skill acquisition, retention, and long-term carryover in a variety of environments. Accurate measurement allows behavioral changes to be observed, and assessments to be made, regarding an individual's ability to adapt during interventions and to incorporate new skills into real-world behaviors. The result of such an approach to assessment may be that interventions truly translate from clinical/laboratory to real-world environments. Future locomotor measurement tools must be based on a theoretical framework that can guide their use to accurately quantify treatment effects and provide a basis upon which to develop and refine therapeutic interventions.
    Journal of neurologic physical therapy: JNPT 03/2012; 36(1):38-44. · 1.65 Impact Factor
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    ABSTRACT: Arm and leg coordination naturally emerges during walking, but can be affected by stroke or Parkinson's disease. The purpose of this preliminary study was to characterize arm and leg coordination during treadmill walking at self-selected comfortable walking speeds (CWSs) in individuals using arm swing with motor incomplete spinal cord injury (iSCI). Hip and shoulder angle cycle durations and amplitudes, strength of peak correlations between contralateral hip and shoulder joint angle time series, the time shifts at which these peak correlations occur, and associated variability were quantified. Outcomes in individuals with iSCI selecting fast CWSs (range, 1.0-1.3m/s) and speed-matched individuals without neurological injuries are similar. Differences, however, are detected in individuals with iSCI selecting slow CWSs (range, 0.25-0.65 m/s) and may represent compensatory strategies to improve walking balance or forward propulsion. These individuals elicit a 1:1, arm:leg frequency ratio versus the 2:1 ratio observed in non-injured individuals. Shoulder and hip movement patterns, however, are highly reproducible (coordinated) in participants with iSCI, regardless of CWS. This high degree of inter-extremity coordination could reflect an inability to modify a single movement pattern post-iSCI. Combined, these data suggest inter-extremity walking coordination may be altered, but is present after iSCI, and therefore may be regulated, in part, by neural control.
    Gait & posture 02/2012; 36(1):49-55. · 2.58 Impact Factor
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    ABSTRACT: Better understanding of fall risk poststroke is required for developing screening and prevention programs. This study characterizes falls in the Locomotor Experience Applied Post-Stroke (LEAPS) randomized clinical trial, describes the impact of 2 walking recovery interventions on falls, and examines the value of clinical assessments for predicting falls. Community-dwelling ambulatory stroke survivors enrolled in LEAPS were assessed 2 months poststroke. Falls were monitored until 12 months poststroke and participants were characterized as multiple or injurious (M/I); single, noninjurious; or nonfallers. Incidence and time to M/I falls were compared across interventions (home exercise and locomotor training initiated 2 months [early-LTP] or 6 months [late-LTP] poststroke). Predictive value of 2-month clinical assessments for falls outcome was assessed. Among the 408 participants, 36.0% were M/I, 21.6% were single, noninjurious, and 42.4% were nonfallers. Most falls occurred at home in the first 3 months after assessment. Falls incidence was highest for those with severe walking impairment who received early-LTP (P=0.025). Berg Balance Scale score ≤ 42/56 was the single best predictor of M/I falls. As individuals with stroke improve in walking capacity, risk for M/I falls remains high. Individuals walking <0.4 m/s are at higher risk for M/I falls if they receive early-LTP training. Berg Balance Scale score at 2 months poststroke is useful for informing falls risk, but it cannot account for the multifactorial nature of the problem. Falls prevention in stroke will require multifactorial risk assessment and management provided concomitantly with exercise interventions to improve mobility. URL: Unique identifier: NCT00243919.
    Stroke 02/2012; 43(2):446-52. · 6.16 Impact Factor
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    ABSTRACT: Spinal cord injury affects walking balance control, which necessitates methods to quantify balance ability. The purposes of this study were to 1) examine walking balance through foot placement variability post-injury; 2) assess the relationship between measures of variability and clinical balance assessments; and 3) determine if spatial parameter variability might be used as a clinical correlate for more complex balance measurements. Ten persons with spinal cord injury walked without devices on a split-belt treadmill at self-selected speeds. Ten healthy controls walked at 0.3 and 0.6m/s for comparison. Variability of step width and length, anteroposterior and mediolateral foot placements relative to center-of-mass, and margin-of-stability were calculated. Clinical assessments included Berg Balance Scale and Dynamic Gait Index. Participants with spinal cord injury demonstrated significantly different variability in all biomechanical measures compared to controls (P ≤ 0.007). Berg Balance Scale scores were significantly inversely associated with step length as well as anteroposterior and mediolateral foot placement variability (P ≤ 0.05). Dynamic Gait Index scores were significantly inversely associated with mediolateral foot placement variability (P ≤ 0.05). Participants with spinal cord injury showed significant correlations between spatial parameter variability and all other measures (P ≤ 0.005), except between step length and margin-of-stability (P=0.068); controls revealed fewer correlations. Persons post-spinal cord injury exhibit an abnormal amount of stepping variability when challenged to walk without devices, yet preserve the ability to avoid falling. When complex laboratory measures of variability are unavailable clinically, spatial parameter variability or standardized balance assessments may be plausible indicators of walking balance control.
    Clinical biomechanics (Bristol, Avon) 02/2012; 27(2):145-50. · 1.76 Impact Factor
  • Preeti Mohandas Nair, George Hornby T, Andrea Louis Behrman
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    ABSTRACT: Gait deviations in individuals after incomplete spinal cord injury (ISCI) that are quantified using spatiotemporal (ST) parameters are often targeted during therapeutic interventions. The purpose of our study was to establish reliability and responsiveness of ST parameters of gait after ISCI using an instrumented walkway (GaitMat II). Sixteen individuals with ISCI participated in the study. Each subject completed at least 2 walking trials at self-selected (SS) walking speed. Intraclass correlation coefficients model 2, 1 (ICC2,1) with 95% confidence intervals (CIs), standard error of measurement (SEM), SEM percent change (SEM%), the minimal detectable change (MDC), and the MDC percent change (MDC%) were determined for 8 ST parameters including step length, single limb support, and double limb support time for the more and less impaired limb, cadence, and speed. Excellent test-retest agreement (0.84-0.99) was observed in all ST parameters. SEM% ranged from 8% to 29%, while MDC% ranged from 21% (cadence) to 80% (double limb support time). MDC% values were relatively higher (5-12 MDC%) for the more versus less impaired limb. SEM% results indicate that small to moderate changes were needed to indicate a real change in walking performance. Differences in MDC% values between limbs indicated that variability in parameters might be sensitive to level of motor impairment. In individuals with ISCI, different gait, balance, or strength training programs can be compared and contrasted based on a quantifiable and meaningful change in the ST parameter of interest.
    Topics in Spinal Cord Injury Rehabilitation 01/2012; 18(3):273-281.

Publication Stats

2k Citations
266.00 Total Impact Points


  • 1998–2014
    • University of Florida
      • Department of Physical Therapy
      Gainesville, Florida, United States
  • 2013
    • Kaye Academic College of Education
      Be'er Sheva`, Southern District, Israel
    • Florida Clinical Research Center
      Florida, United States
  • 2012–2013
    • Medical University of South Carolina
      • Department of Health Science and Research
      Charleston, South Carolina, United States
    • Seton Hall University
      • School of Health and Medical Sciences
      South Orange, NJ, United States
    • University of Southern California
      • Division of Biokinesiology and Physical Therapy
      Los Angeles, CA, United States
    • Cardinal Hill Rehabilitation Hospital
      Lexington, Kentucky, United States
    • Shepherd Center
      Atlanta, Georgia, United States
  • 2011–2013
    • University of Louisville
      • Department of Neurological Surgery
      Louisville, Kentucky, United States
    • Angelo State University
      San Angelo, Texas, United States
    • Duke University
      Durham, North Carolina, United States
  • 2010–2012
    • McKnight Brain Institute
      Gainesville, Florida, United States
    • Northeastern University
      • Department of Physical Therapy
      Boston, MA, United States
  • 2006
    • North Florida and South Georgia Veterans Health System
      Gainesville, Florida, United States