Kalyna Bohuslava | Winebrenner Theological Seminary (original) (raw)

Papers by Kalyna Bohuslava

Research paper thumbnail of The Art and Science of Wine Making

This paper explores the multifaceted world of wine, examining its historical significance, produc... more This paper explores the multifaceted world of wine, examining its historical significance, production processes, and cultural impact. Beginning with a historical overview, it traces the origins of wine from ancient civilizations to modern winemaking practices. The paper delves into the intricacies of viticulture and vinification, highlighting the delicate balance of art and science that defines the wine-making process. The concept of terroir is emphasized, illustrating how environmental factors shape the unique characteristics of wines from different regions. Additionally, the paper discusses the importance of wine and food pairings, enhancing culinary experiences through complementary flavors. Finally, it reflects on the cultural significance of wine as a symbol of celebration and community, underscoring its enduring role in social rituals. Through this comprehensive examination, the paper aims to deepen the reader's appreciation for wine, inviting a greater understanding of its journey from vine to glass.

Research paper thumbnail of Falls in the Medicare Population: Incidence, Associated Factors, and Impact on Health Care

Background and Purpose. Falls are a major health problem in the elderly community; however, quest... more Background and Purpose. Falls are a major health problem in the elderly community; however, questions regarding incidence, risk factors, and provider response to falls exist. The purpose of this study was to examine the incidence of falls, associated factors, health care costs, and provider response to falls among Medicare beneficiaries.

Research paper thumbnail of Training of Balance Under Single and Dual-Task Conditions in Older Adults With Balance Impairment

Background and Purpose. Traditionally, rehabilitation programs emphasize training balance under s... more Background and Purpose. Traditionally, rehabilitation programs emphasize training balance under single-task conditions to improve balance and reduce risk for falls. The purpose of this case report is to describe 3 balance training approaches in older adults with impaired balance. Case Descriptions. Three patients were randomly assigned to 1 of 3 interventions: (1) single-task balance training, (2) dual-task training under a fixed-priority instructional set, and (3) dual-task training under a variable-priority instructional set. Outcomes. The patients who received balance training under dual-task conditions showed dual-task training benefits; these training benefits were maintained for 3 months. The patient who received variable-priority training showed improvement on novel dual tasks. Discussion. Older adults may be able to improve their balance under dual-task conditions only following specific types of balance training. This case report gives insight on how this intervention might be combined with more traditional physical therapy intervention. [Silsupadol P, Siu KC, Shumway-Cook A, Woollacott MH. Training of balance under singleand dual-task conditions in older adults with balance impairment. Phys Ther. 2006;86:269 -281.] 27 Shumway-Cook A, Woollacott M, Kerns KA, Baldwin M. The effects of two types of cognitive tasks on postural stability in older adults with and without a history of falls.

Research paper thumbnail of Postural dysfunction during standing and walking in children with cerebral palsy: what are the underlying problems and what new therapies might improve balance?

Neural plasticity, 2005

In this review we explore studies related to constraints on balance and walking in children with ... more In this review we explore studies related to constraints on balance and walking in children with cerebral palsy (CP) and the efficacy of training reactive balance (recovering from a slip induced by a platform displacement) in children with both spastic hemiplegic and diplegic CP. Children with CP show (a) crouched posture, contributing to decreased ability to recover balance (longer time/increased sway); (b) delayed responses in ankle muscles; (c) inappropriate muscle response sequencing; (d) increased coactivation of agonists/antagonists. Constraints on gait include (a) crouched gait; (b) increased co-activation of agonists/antagonists; (c) decreased muscle activation; (d) spasticity. The efficiency of balance recovery can be improved in children with CP, indicated by both a reduction in the total center of pressure path used during balance recovery and in the time to restabilize balance after training. Changes in muscle response characteristics contributing to improved recovery in...

Research paper thumbnail of Expanding the scoring system for the Dynamic Gait Index

Physical therapy, 2013

The Dynamic Gait Index (DGI) measures the capacity to adapt gait to complex tasks. The current sc... more The Dynamic Gait Index (DGI) measures the capacity to adapt gait to complex tasks. The current scoring system combining gait pattern (GP) and level of assistance (LOA) lacks clarity, and the test has a limited range of measurement. This study developed a new scoring system based on 3 facets of performance (LOA, GP, and time) and examined the psychometric properties of the modified DGI (mDGI). A cross-sectional, descriptive study was conducted. Nine hundred ninety-five participants (855 patients with neurologic pathology and mobility impairments [MI group] and 140 patients without neurological impairment [control group]) were tested. Interrater reliability was calculated using kappa coefficients. Internal consistency was computed using the Cronbach alpha coefficient. Factor analysis and Rasch analysis investigated unidimensionality and range of difficulty. Internal validity was determined by comparing groups using multiple t tests. Minimal detectable change (MDC) was calculated for t...

Research paper thumbnail of Examining the Relationship Between Medical Diagnoses and Patterns of Performance on the Modified Dynamic Gait Index

Physical therapy, Jan 4, 2014

In the original and modified Dynamic Gait Index (mDGI), 8 tasks are used to measure mobility; how... more In the original and modified Dynamic Gait Index (mDGI), 8 tasks are used to measure mobility; however, disagreement exists regarding whether all tasks are necessary. The relationship between mDGI scores and Centers for Medicare & Medicaid Services (CMS) severity indicators in the mobility domain has not been explored. The study objectives were to examine the relationship between medical diagnoses and mDGI scores, to determine whether administration of the mDGI can be shortened on the basis of expected diagnostic patterns of performance, and to create a model in which mDGI scores are mapped to CMS severity modifiers. This was a cross-sectional, descriptive study. The 794 participants included 140 people without impairments (control cohort) and 239 people with stroke, 140 with vestibular dysfunction, 100 with traumatic brain injury, 91 with gait abnormality, and 84 with Parkinson disease. Scores on the mDGI (total, performance facet, and task) for the control cohort were compared with...

Research paper thumbnail of A critical examination of vestibular function in motor-impaired learning-disabled children

International Journal of Pediatric Otorhinolaryngology, 1987

This study examined the role of the vestibular system in balance and coordination problems found ... more This study examined the role of the vestibular system in balance and coordination problems found in motor-impaired, learning-disabled (LD) children. Vestibulo-ocular reflex (VOR) and vestibulo-spinal tests (moving platform posturography) were performed on 15 learning disabled and 54 normal children. Twelve LD children had normal VOR scores suggesting normal peripheral vestibular inputs. All 15 LD children had abnormal posturography. Motor-impaired LD children could not appropriately integrate vestibular information with visual and somatosensory inputs for postural orientation. Results suggest that the best discriminator of abnormal sensorimotor function in LD children are posturography trials requiring orientation to gravity despite absent or inaccurate visual and somatosensory cues, rather than traditionally relied on VOR and Romberg tests.

Research paper thumbnail of Incidence of and Risk Factors for Falls Following Hip Fracture in Community-dwelling Older Adults

APTA is a sponsor of the Decade, an international, multidisciplinary initiative to improve health... more APTA is a sponsor of the Decade, an international, multidisciplinary initiative to improve health-related quality of life for people with musculoskeletal disorders.

Research paper thumbnail of Falls in the Medicare Population: Incidence, Associated Factors, and Impact on Health Care

Physical Therapy, 2009

Background and Purpose. Falls are a major health problem in the elderly community; however, quest... more Background and Purpose. Falls are a major health problem in the elderly community; however, questions regarding incidence, risk factors, and provider response to falls exist. The purpose of this study was to examine the incidence of falls, associated factors, health care costs, and provider response to falls among Medicare beneficiaries.

Research paper thumbnail of Evidence for the Validity of the Modified Dynamic Gait Index Across Diagnostic Groups

Research paper thumbnail of Selective utilization of spatial working memory resources during stance posture

NeuroReport, 2005

While it has been shown that visual imagery tasks interfere with balance control, the neural mech... more While it has been shown that visual imagery tasks interfere with balance control, the neural mechanisms underlying the interference are unclear. Within a healthy young adult population, we employed a dual-task methodology to investigate the role of visual working memory in stance postural control. The employment of specific visual object and visual spatial working memory cognitive tasks facilitated the selective activation of cortically dissociated working memory resources. Challenging postural sets did not significantly impact object working memory performance, but clearly degraded performance on a spatial working memory task, suggesting that interactions between stance postural control and visual working memory are limited to the spatial domain. Results demonstrated no significant effect of the cognitive tasks upon postural stability.

Research paper thumbnail of Staged unilateral versus bilateral subthalamic nucleus stimulator implantation in Parkinson disease

Movement Disorders, 2007

In 17 consecutive patients with Parkinson disease (PD), bilateral subthalamic nucleus (STN) stimu... more In 17 consecutive patients with Parkinson disease (PD), bilateral subthalamic nucleus (STN) stimulators were implanted during staged surgeries. The Unified Parkinson Disease Rating Scale (UPDRS) and the Dyskinesia Disability Scale were completed both off and on medication prior to any surgery and also OFF and ON stimulation after each surgery. On-medication UPDRS activities of daily living (ADL) and motor examination scores changed little with unilateral or bilateral stimulation. Off-medication UPDRS motor examination scores improved to similar degrees after each staged STN electrode implantation. Most of the improvements in off-medication ADL scores, dyskinesia scores, complications of therapy, and medication dose reduction occurred after unilateral STN stimulation with smaller improvements after the second operation.

Research paper thumbnail of Environmental Components of Mobility Disability in Community-Living Older Persons

Journal of the American Geriatrics Society, 2000

To examine the relationship between characteristics of the physical environment and mobility disa... more To examine the relationship between characteristics of the physical environment and mobility disability in community-living older persons. Cross-sectional study conducted on three groups of community-dwelling older adults. Community-dwelling older people in Seattle, Washington, and Waterloo, Ontario, Canada. Fifty-four older adults (> or =70) were recruited from two geographic sites and grouped according to level of physical function (elite, physically able, physically disabled). Subjects reported on frequency of encounter versus avoidance of 24 features of the physical environment, grouped into eight dimensions, using a five-point ordinal scale (never, rarely, sometimes, often, always). Never and rarely responses were combined and coded as not encountered or not avoided, whereas the sometimes, often or always responses were combined and coded as encountered or avoided. Disabled older adults reported fewer encounters with and concomitantly greater avoidance of physical challenges to mobility than nondisabled older adults. However, both encounter and avoidance varied by environmental dimension. Results support the hypothesis that mobility disability results from an interaction of individual and environmental factors. Mobility disability is associated with avoidance of some, but not all, physically challenging features within the environment, suggesting that some environmental features may disable community mobility more than others.

Research paper thumbnail of Mobility Limitations in the Medicare Population: Prevalence and Sociodemographic and Clinical Correlates

Journal of the American Geriatrics Society, 2000

Research paper thumbnail of Gamma knife radiosurgery as a lesioning technique in movement disorder surgery

Journal of Neurosurgery, 1998

To increase knowledge of the safety and efficacy of the use of gamma knife radiosurgery in patien... more To increase knowledge of the safety and efficacy of the use of gamma knife radiosurgery in patients with movement disorders, the authors describe their own experience in this field and include blinded independent assessments of their results. Fifty-five patients underwent radiosurgical placement of lesions either in the thalamus (27 patients) or globus pallidus (28 patients) for treatment of movement disorders. Patients were evaluated pre- and postoperatively by a team of observers skilled in the assessment of gait and movement disorders who were blinded to the procedure performed. The observers were not associated with the surgical team and concomitantly and blindly also assessed a group of 11 control patients with Parkinson's disease who did not undergo any surgical procedures. All stereotactic lesions were made with the Leksell gamma unit using the 4-mm secondary collimator helmet and a single isocenter with maximum doses from 120 to 160 Gy. Clinical follow-up evaluation indicated that 88% of patients who underwent thalamotomy became tremor free or nearly tremor free. Statistically significant improvements in performance were noted in the independent assessments of Unified Parkinson's Disease Rating Scale (UPDRS) scores in the patients undergoing thalamotomy. Of patients undergoing pallidotomy who had exhibited levodopainduced dyskinesias, 85.7% had total or near-total relief of that symptom. Clinical assessment indicated improvements in bradykinesia and rigidity in 64.3% of patients who underwent pallidotomy. Independent blinded assessments did not reveal statistically significant improvements in Hoehn and Yahr scores or UPDRS scores. On the other hand, 64.7% of patients showed improvements in subscores of the UPDRS, including activities of daily living (58%), total contralateral score (58%), and contralateral motor scores (47%). Total ipsilateral score and ipsilateral motor scores were both improved in 59% of patients. One (1.8%) of 55 patients experienced a homonymous hemianopsia 9 months after pallidotomy due to an unexpectedly large lesion. No other complications of any kind were seen. Neuropsychological test scores that were obtained for the combined pallidotomy and thalamotomy treatment groups preoperatively and at 6 months postoperatively demonstrated an absence of cognitive morbidity. Follow-up neuroimaging confirmed correct lesion location in all patients, with a mean maximum deviation from the planned target of 1 mm in the vertical axis. Measurements of lesions at regular intervals on postoperative magnetic resonance images demonstrated considerable variability in lesion volumes. The safety and efficacy of functional lesions made with the gamma knife appear to be similar to those made with the assistance of electrophysiological guidance with open functional stereotactic procedures. Functional lesions may be made safely and accurately using gamma knife radiosurgical techniques. The efficacy is equivalent to that reported for open techniques that use radiofrequency lesioning methods with electrophysiological guidance. Complications are very infrequent with the radiosurgical method. The use of functional radiosurgical lesioning to treat movement disorders is particularly attractive in older patients and in those with major systemic diseases or coagulopathies; its use in the general movement disorder population seems reasonable as well.

Research paper thumbnail of Cognitive Influence on Postural Stability: A Neuromuscular Analysis in Young and Older Adults

The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 2000

Background. Previous literature indicates that attentional resources are required for recovery of... more Background. Previous literature indicates that attentional resources are required for recovery of postural stability. Previous studies have also examined the effect of aging on the performance of a static postural task while a secondary cognitive task is being conducted. This study describes the effect of a cognitive task on the neuromuscular response characteristics underlying reactive balance control in young versus older adults.

Research paper thumbnail of The effects of age on medio-lateral stability during normal and narrow base walking

Gait & Posture, 2008

We examined age-related differences in frontal plane stability during performance of narrow base ... more We examined age-related differences in frontal plane stability during performance of narrow base (NB) walking relative to usual gait. A cross-sectional analysis of participants from the Baltimore Longitudinal Study of Aging (BLSA) was performed on data from the BLSA Motion Analysis Laboratory. Participants were thirty-four adults aged 54 to 92 without history of falls. We measured step error rates during NB gait and spatial-temporal parameters, frontal plane stability, and gait variability during usual and NB gait. There was a non-significant age-associated linear increase in step error rate (P = 0.12) during NB gait. With increasing age, step width increased (P=0.002) and step length and stride velocity decreased (P<0.001), especially during NB gait. Age-associated increases in medio-lateral (M-L) center of mass (COM) peak velocity (P<0.001) and displacement (P=0.005) were also greater during NB compared to usual gait. With increasing age there was greater variability in stride velocity (P=0.001) and step length (P<0.001) under both conditions. Ageassociated differences related to M-L COM stability suggest that the quantification of COM control during NB gait may improve identification of older persons at increased falls risk.

Research paper thumbnail of The influence of a concurrent cognitive task on the compensatory stepping response to a perturbation in balance-impaired and healthy elders

Gait & Posture, 2002

This study investigated the influence of a concurrent cognitive task on the compensatory stepping... more This study investigated the influence of a concurrent cognitive task on the compensatory stepping response in balance-impaired elders and the attentional demand of the stepping response. Kinetic, kinematic and neuromuscular measures of a forward recovery step were investigated in 15 young adults, 15 healthy elders and 13 balance-impaired elders in a single task (postural recovery only) and dual task (postural recovery and vocal reaction time task) situation. Results revealed that reaction times were longer in all subjects when performed concurrently with a compensatory step, they were longer for a step than an in-place response and longer for balance-impaired older adults compared with young adults. An interesting finding was that the latter group difference may be related to prioritization between the two tasks rather than attentional demand, as the older adults completed the step before the reaction time, whereas the young adults could perform both concurrently. Few differences in step characteristics were found between tasks, with the most notable being a delayed latency and reduced magnitude of the early automatic postural response in healthy and balance-impaired elders with a concurrent task.

Research paper thumbnail of Attention and the control of posture and gait: a review of an emerging area of research

Gait & Posture, 2002

Research on the relationship between attention and the control of posture and gait is a new and e... more Research on the relationship between attention and the control of posture and gait is a new and expanding area with studies on young adults revealing the role of cognitive factors in the control of balance during standing and walking. The use of dual task paradigms to examine the effect of age related changes in attentional requirements of balance control and age-related reductions in stability when performing a secondary task has shown that these are important contributors to instability in both healthy and balance-impaired older adults. The attentional demands of balance control vary depending on the complexity of the task and the type of secondary task being performed. New clinical assessment methods incorporating dual-task paradigms are helpful in revealing the effect of disease (e.g. Parkinson's disease) on the ability to allocate attention to postural tasks and appear to be sensitive measures in both predicting fall risk and in documenting recovery of stability.

Research paper thumbnail of Training-related changes in dual-task walking performance of elderly persons with balance impairment: A double-blind, randomized controlled trial

Gait & Posture, 2009

The purpose of this study was to compare the efficiency of three different balance training strat... more The purpose of this study was to compare the efficiency of three different balance training strategies in an effort to understand the mechanisms underlying training-related changes in dual-task balance performance of older adults with balance impairment. Elderly individuals with balance impairment, age 65 and older, were randomly assigned to one of three individualized training programs: singletask (ST) balance training; dual-task training with fixed-priority (FP) instruction; and dual-task training with variable-priority (VP) instruction. Balance control during gait, under practiced and novel conditions, was assessed by calculating the center of mass and ankle joint center inclination angles in the frontal plane. A smaller angle indicated better balance performance. Other outcomes included gait velocity, stride length, verbal reaction time, and rate of response. All measures were collected at baseline and the end of the 4-week training. Results indicated that all training strategies were equally effective (P > .05) at improving balance performance (smaller inclination angle) under single-task contexts. However, the VP training strategy was more effective (P = .04) in improving both balance and cognitive performance under dual-task conditions than either the ST or the FP training strategies. Improved dual-task processing skills did not transfer to a novel dual-task condition. Results support Kramer et al.'s proposal that VP training improves both single-task automatization and the development of task-coordination skills.

Research paper thumbnail of The Art and Science of Wine Making

This paper explores the multifaceted world of wine, examining its historical significance, produc... more This paper explores the multifaceted world of wine, examining its historical significance, production processes, and cultural impact. Beginning with a historical overview, it traces the origins of wine from ancient civilizations to modern winemaking practices. The paper delves into the intricacies of viticulture and vinification, highlighting the delicate balance of art and science that defines the wine-making process. The concept of terroir is emphasized, illustrating how environmental factors shape the unique characteristics of wines from different regions. Additionally, the paper discusses the importance of wine and food pairings, enhancing culinary experiences through complementary flavors. Finally, it reflects on the cultural significance of wine as a symbol of celebration and community, underscoring its enduring role in social rituals. Through this comprehensive examination, the paper aims to deepen the reader's appreciation for wine, inviting a greater understanding of its journey from vine to glass.

Research paper thumbnail of Falls in the Medicare Population: Incidence, Associated Factors, and Impact on Health Care

Background and Purpose. Falls are a major health problem in the elderly community; however, quest... more Background and Purpose. Falls are a major health problem in the elderly community; however, questions regarding incidence, risk factors, and provider response to falls exist. The purpose of this study was to examine the incidence of falls, associated factors, health care costs, and provider response to falls among Medicare beneficiaries.

Research paper thumbnail of Training of Balance Under Single and Dual-Task Conditions in Older Adults With Balance Impairment

Background and Purpose. Traditionally, rehabilitation programs emphasize training balance under s... more Background and Purpose. Traditionally, rehabilitation programs emphasize training balance under single-task conditions to improve balance and reduce risk for falls. The purpose of this case report is to describe 3 balance training approaches in older adults with impaired balance. Case Descriptions. Three patients were randomly assigned to 1 of 3 interventions: (1) single-task balance training, (2) dual-task training under a fixed-priority instructional set, and (3) dual-task training under a variable-priority instructional set. Outcomes. The patients who received balance training under dual-task conditions showed dual-task training benefits; these training benefits were maintained for 3 months. The patient who received variable-priority training showed improvement on novel dual tasks. Discussion. Older adults may be able to improve their balance under dual-task conditions only following specific types of balance training. This case report gives insight on how this intervention might be combined with more traditional physical therapy intervention. [Silsupadol P, Siu KC, Shumway-Cook A, Woollacott MH. Training of balance under singleand dual-task conditions in older adults with balance impairment. Phys Ther. 2006;86:269 -281.] 27 Shumway-Cook A, Woollacott M, Kerns KA, Baldwin M. The effects of two types of cognitive tasks on postural stability in older adults with and without a history of falls.

Research paper thumbnail of Postural dysfunction during standing and walking in children with cerebral palsy: what are the underlying problems and what new therapies might improve balance?

Neural plasticity, 2005

In this review we explore studies related to constraints on balance and walking in children with ... more In this review we explore studies related to constraints on balance and walking in children with cerebral palsy (CP) and the efficacy of training reactive balance (recovering from a slip induced by a platform displacement) in children with both spastic hemiplegic and diplegic CP. Children with CP show (a) crouched posture, contributing to decreased ability to recover balance (longer time/increased sway); (b) delayed responses in ankle muscles; (c) inappropriate muscle response sequencing; (d) increased coactivation of agonists/antagonists. Constraints on gait include (a) crouched gait; (b) increased co-activation of agonists/antagonists; (c) decreased muscle activation; (d) spasticity. The efficiency of balance recovery can be improved in children with CP, indicated by both a reduction in the total center of pressure path used during balance recovery and in the time to restabilize balance after training. Changes in muscle response characteristics contributing to improved recovery in...

Research paper thumbnail of Expanding the scoring system for the Dynamic Gait Index

Physical therapy, 2013

The Dynamic Gait Index (DGI) measures the capacity to adapt gait to complex tasks. The current sc... more The Dynamic Gait Index (DGI) measures the capacity to adapt gait to complex tasks. The current scoring system combining gait pattern (GP) and level of assistance (LOA) lacks clarity, and the test has a limited range of measurement. This study developed a new scoring system based on 3 facets of performance (LOA, GP, and time) and examined the psychometric properties of the modified DGI (mDGI). A cross-sectional, descriptive study was conducted. Nine hundred ninety-five participants (855 patients with neurologic pathology and mobility impairments [MI group] and 140 patients without neurological impairment [control group]) were tested. Interrater reliability was calculated using kappa coefficients. Internal consistency was computed using the Cronbach alpha coefficient. Factor analysis and Rasch analysis investigated unidimensionality and range of difficulty. Internal validity was determined by comparing groups using multiple t tests. Minimal detectable change (MDC) was calculated for t...

Research paper thumbnail of Examining the Relationship Between Medical Diagnoses and Patterns of Performance on the Modified Dynamic Gait Index

Physical therapy, Jan 4, 2014

In the original and modified Dynamic Gait Index (mDGI), 8 tasks are used to measure mobility; how... more In the original and modified Dynamic Gait Index (mDGI), 8 tasks are used to measure mobility; however, disagreement exists regarding whether all tasks are necessary. The relationship between mDGI scores and Centers for Medicare & Medicaid Services (CMS) severity indicators in the mobility domain has not been explored. The study objectives were to examine the relationship between medical diagnoses and mDGI scores, to determine whether administration of the mDGI can be shortened on the basis of expected diagnostic patterns of performance, and to create a model in which mDGI scores are mapped to CMS severity modifiers. This was a cross-sectional, descriptive study. The 794 participants included 140 people without impairments (control cohort) and 239 people with stroke, 140 with vestibular dysfunction, 100 with traumatic brain injury, 91 with gait abnormality, and 84 with Parkinson disease. Scores on the mDGI (total, performance facet, and task) for the control cohort were compared with...

Research paper thumbnail of A critical examination of vestibular function in motor-impaired learning-disabled children

International Journal of Pediatric Otorhinolaryngology, 1987

This study examined the role of the vestibular system in balance and coordination problems found ... more This study examined the role of the vestibular system in balance and coordination problems found in motor-impaired, learning-disabled (LD) children. Vestibulo-ocular reflex (VOR) and vestibulo-spinal tests (moving platform posturography) were performed on 15 learning disabled and 54 normal children. Twelve LD children had normal VOR scores suggesting normal peripheral vestibular inputs. All 15 LD children had abnormal posturography. Motor-impaired LD children could not appropriately integrate vestibular information with visual and somatosensory inputs for postural orientation. Results suggest that the best discriminator of abnormal sensorimotor function in LD children are posturography trials requiring orientation to gravity despite absent or inaccurate visual and somatosensory cues, rather than traditionally relied on VOR and Romberg tests.

Research paper thumbnail of Incidence of and Risk Factors for Falls Following Hip Fracture in Community-dwelling Older Adults

APTA is a sponsor of the Decade, an international, multidisciplinary initiative to improve health... more APTA is a sponsor of the Decade, an international, multidisciplinary initiative to improve health-related quality of life for people with musculoskeletal disorders.

Research paper thumbnail of Falls in the Medicare Population: Incidence, Associated Factors, and Impact on Health Care

Physical Therapy, 2009

Background and Purpose. Falls are a major health problem in the elderly community; however, quest... more Background and Purpose. Falls are a major health problem in the elderly community; however, questions regarding incidence, risk factors, and provider response to falls exist. The purpose of this study was to examine the incidence of falls, associated factors, health care costs, and provider response to falls among Medicare beneficiaries.

Research paper thumbnail of Evidence for the Validity of the Modified Dynamic Gait Index Across Diagnostic Groups

Research paper thumbnail of Selective utilization of spatial working memory resources during stance posture

NeuroReport, 2005

While it has been shown that visual imagery tasks interfere with balance control, the neural mech... more While it has been shown that visual imagery tasks interfere with balance control, the neural mechanisms underlying the interference are unclear. Within a healthy young adult population, we employed a dual-task methodology to investigate the role of visual working memory in stance postural control. The employment of specific visual object and visual spatial working memory cognitive tasks facilitated the selective activation of cortically dissociated working memory resources. Challenging postural sets did not significantly impact object working memory performance, but clearly degraded performance on a spatial working memory task, suggesting that interactions between stance postural control and visual working memory are limited to the spatial domain. Results demonstrated no significant effect of the cognitive tasks upon postural stability.

Research paper thumbnail of Staged unilateral versus bilateral subthalamic nucleus stimulator implantation in Parkinson disease

Movement Disorders, 2007

In 17 consecutive patients with Parkinson disease (PD), bilateral subthalamic nucleus (STN) stimu... more In 17 consecutive patients with Parkinson disease (PD), bilateral subthalamic nucleus (STN) stimulators were implanted during staged surgeries. The Unified Parkinson Disease Rating Scale (UPDRS) and the Dyskinesia Disability Scale were completed both off and on medication prior to any surgery and also OFF and ON stimulation after each surgery. On-medication UPDRS activities of daily living (ADL) and motor examination scores changed little with unilateral or bilateral stimulation. Off-medication UPDRS motor examination scores improved to similar degrees after each staged STN electrode implantation. Most of the improvements in off-medication ADL scores, dyskinesia scores, complications of therapy, and medication dose reduction occurred after unilateral STN stimulation with smaller improvements after the second operation.

Research paper thumbnail of Environmental Components of Mobility Disability in Community-Living Older Persons

Journal of the American Geriatrics Society, 2000

To examine the relationship between characteristics of the physical environment and mobility disa... more To examine the relationship between characteristics of the physical environment and mobility disability in community-living older persons. Cross-sectional study conducted on three groups of community-dwelling older adults. Community-dwelling older people in Seattle, Washington, and Waterloo, Ontario, Canada. Fifty-four older adults (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; or =70) were recruited from two geographic sites and grouped according to level of physical function (elite, physically able, physically disabled). Subjects reported on frequency of encounter versus avoidance of 24 features of the physical environment, grouped into eight dimensions, using a five-point ordinal scale (never, rarely, sometimes, often, always). Never and rarely responses were combined and coded as not encountered or not avoided, whereas the sometimes, often or always responses were combined and coded as encountered or avoided. Disabled older adults reported fewer encounters with and concomitantly greater avoidance of physical challenges to mobility than nondisabled older adults. However, both encounter and avoidance varied by environmental dimension. Results support the hypothesis that mobility disability results from an interaction of individual and environmental factors. Mobility disability is associated with avoidance of some, but not all, physically challenging features within the environment, suggesting that some environmental features may disable community mobility more than others.

Research paper thumbnail of Mobility Limitations in the Medicare Population: Prevalence and Sociodemographic and Clinical Correlates

Journal of the American Geriatrics Society, 2000

Research paper thumbnail of Gamma knife radiosurgery as a lesioning technique in movement disorder surgery

Journal of Neurosurgery, 1998

To increase knowledge of the safety and efficacy of the use of gamma knife radiosurgery in patien... more To increase knowledge of the safety and efficacy of the use of gamma knife radiosurgery in patients with movement disorders, the authors describe their own experience in this field and include blinded independent assessments of their results. Fifty-five patients underwent radiosurgical placement of lesions either in the thalamus (27 patients) or globus pallidus (28 patients) for treatment of movement disorders. Patients were evaluated pre- and postoperatively by a team of observers skilled in the assessment of gait and movement disorders who were blinded to the procedure performed. The observers were not associated with the surgical team and concomitantly and blindly also assessed a group of 11 control patients with Parkinson&#39;s disease who did not undergo any surgical procedures. All stereotactic lesions were made with the Leksell gamma unit using the 4-mm secondary collimator helmet and a single isocenter with maximum doses from 120 to 160 Gy. Clinical follow-up evaluation indicated that 88% of patients who underwent thalamotomy became tremor free or nearly tremor free. Statistically significant improvements in performance were noted in the independent assessments of Unified Parkinson&#39;s Disease Rating Scale (UPDRS) scores in the patients undergoing thalamotomy. Of patients undergoing pallidotomy who had exhibited levodopainduced dyskinesias, 85.7% had total or near-total relief of that symptom. Clinical assessment indicated improvements in bradykinesia and rigidity in 64.3% of patients who underwent pallidotomy. Independent blinded assessments did not reveal statistically significant improvements in Hoehn and Yahr scores or UPDRS scores. On the other hand, 64.7% of patients showed improvements in subscores of the UPDRS, including activities of daily living (58%), total contralateral score (58%), and contralateral motor scores (47%). Total ipsilateral score and ipsilateral motor scores were both improved in 59% of patients. One (1.8%) of 55 patients experienced a homonymous hemianopsia 9 months after pallidotomy due to an unexpectedly large lesion. No other complications of any kind were seen. Neuropsychological test scores that were obtained for the combined pallidotomy and thalamotomy treatment groups preoperatively and at 6 months postoperatively demonstrated an absence of cognitive morbidity. Follow-up neuroimaging confirmed correct lesion location in all patients, with a mean maximum deviation from the planned target of 1 mm in the vertical axis. Measurements of lesions at regular intervals on postoperative magnetic resonance images demonstrated considerable variability in lesion volumes. The safety and efficacy of functional lesions made with the gamma knife appear to be similar to those made with the assistance of electrophysiological guidance with open functional stereotactic procedures. Functional lesions may be made safely and accurately using gamma knife radiosurgical techniques. The efficacy is equivalent to that reported for open techniques that use radiofrequency lesioning methods with electrophysiological guidance. Complications are very infrequent with the radiosurgical method. The use of functional radiosurgical lesioning to treat movement disorders is particularly attractive in older patients and in those with major systemic diseases or coagulopathies; its use in the general movement disorder population seems reasonable as well.

Research paper thumbnail of Cognitive Influence on Postural Stability: A Neuromuscular Analysis in Young and Older Adults

The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 2000

Background. Previous literature indicates that attentional resources are required for recovery of... more Background. Previous literature indicates that attentional resources are required for recovery of postural stability. Previous studies have also examined the effect of aging on the performance of a static postural task while a secondary cognitive task is being conducted. This study describes the effect of a cognitive task on the neuromuscular response characteristics underlying reactive balance control in young versus older adults.

Research paper thumbnail of The effects of age on medio-lateral stability during normal and narrow base walking

Gait & Posture, 2008

We examined age-related differences in frontal plane stability during performance of narrow base ... more We examined age-related differences in frontal plane stability during performance of narrow base (NB) walking relative to usual gait. A cross-sectional analysis of participants from the Baltimore Longitudinal Study of Aging (BLSA) was performed on data from the BLSA Motion Analysis Laboratory. Participants were thirty-four adults aged 54 to 92 without history of falls. We measured step error rates during NB gait and spatial-temporal parameters, frontal plane stability, and gait variability during usual and NB gait. There was a non-significant age-associated linear increase in step error rate (P = 0.12) during NB gait. With increasing age, step width increased (P=0.002) and step length and stride velocity decreased (P<0.001), especially during NB gait. Age-associated increases in medio-lateral (M-L) center of mass (COM) peak velocity (P<0.001) and displacement (P=0.005) were also greater during NB compared to usual gait. With increasing age there was greater variability in stride velocity (P=0.001) and step length (P<0.001) under both conditions. Ageassociated differences related to M-L COM stability suggest that the quantification of COM control during NB gait may improve identification of older persons at increased falls risk.

Research paper thumbnail of The influence of a concurrent cognitive task on the compensatory stepping response to a perturbation in balance-impaired and healthy elders

Gait & Posture, 2002

This study investigated the influence of a concurrent cognitive task on the compensatory stepping... more This study investigated the influence of a concurrent cognitive task on the compensatory stepping response in balance-impaired elders and the attentional demand of the stepping response. Kinetic, kinematic and neuromuscular measures of a forward recovery step were investigated in 15 young adults, 15 healthy elders and 13 balance-impaired elders in a single task (postural recovery only) and dual task (postural recovery and vocal reaction time task) situation. Results revealed that reaction times were longer in all subjects when performed concurrently with a compensatory step, they were longer for a step than an in-place response and longer for balance-impaired older adults compared with young adults. An interesting finding was that the latter group difference may be related to prioritization between the two tasks rather than attentional demand, as the older adults completed the step before the reaction time, whereas the young adults could perform both concurrently. Few differences in step characteristics were found between tasks, with the most notable being a delayed latency and reduced magnitude of the early automatic postural response in healthy and balance-impaired elders with a concurrent task.

Research paper thumbnail of Attention and the control of posture and gait: a review of an emerging area of research

Gait & Posture, 2002

Research on the relationship between attention and the control of posture and gait is a new and e... more Research on the relationship between attention and the control of posture and gait is a new and expanding area with studies on young adults revealing the role of cognitive factors in the control of balance during standing and walking. The use of dual task paradigms to examine the effect of age related changes in attentional requirements of balance control and age-related reductions in stability when performing a secondary task has shown that these are important contributors to instability in both healthy and balance-impaired older adults. The attentional demands of balance control vary depending on the complexity of the task and the type of secondary task being performed. New clinical assessment methods incorporating dual-task paradigms are helpful in revealing the effect of disease (e.g. Parkinson's disease) on the ability to allocate attention to postural tasks and appear to be sensitive measures in both predicting fall risk and in documenting recovery of stability.

Research paper thumbnail of Training-related changes in dual-task walking performance of elderly persons with balance impairment: A double-blind, randomized controlled trial

Gait & Posture, 2009

The purpose of this study was to compare the efficiency of three different balance training strat... more The purpose of this study was to compare the efficiency of three different balance training strategies in an effort to understand the mechanisms underlying training-related changes in dual-task balance performance of older adults with balance impairment. Elderly individuals with balance impairment, age 65 and older, were randomly assigned to one of three individualized training programs: singletask (ST) balance training; dual-task training with fixed-priority (FP) instruction; and dual-task training with variable-priority (VP) instruction. Balance control during gait, under practiced and novel conditions, was assessed by calculating the center of mass and ankle joint center inclination angles in the frontal plane. A smaller angle indicated better balance performance. Other outcomes included gait velocity, stride length, verbal reaction time, and rate of response. All measures were collected at baseline and the end of the 4-week training. Results indicated that all training strategies were equally effective (P > .05) at improving balance performance (smaller inclination angle) under single-task contexts. However, the VP training strategy was more effective (P = .04) in improving both balance and cognitive performance under dual-task conditions than either the ST or the FP training strategies. Improved dual-task processing skills did not transfer to a novel dual-task condition. Results support Kramer et al.'s proposal that VP training improves both single-task automatization and the development of task-coordination skills.