Susan E. White

The Impact of Different Types of Assistive Devices on Gait Measures and Safety in Huntington's Disease

Background Gait and balance impairments lead to frequent falls and injuries in individuals with Huntingtons disease (HD). Assistive devices (ADs) such as canes and walkers are often prescribed to prevent falls, but their efficacy is unknown. We systematically examined the effects of different types of ADs on quantitative gait measures during walking in a straight path and around obstacles. Methods Spatial and temporal gait parameters were measured in 21 subjects with HD as they walked across a GAITRite walkway under 7 conditions (i.e., using no AD and 6 commonly prescribed ADs: a cane, a weighted cane, a standard walker, and a 2, 3 or 4 wheeled walker). Subjects also were timed and observed for number of stumbles and falls while walking around two obstacles in a figure-of-eight pattern. Results Gait measure variability (i.e., coefficient of variation), an indicator of fall risk, was consistently better when using the 4WW compared to other ADs. Subjects also walked the fastest and had the fewest number of stumbles and falls when using the 4WW in the figure-of-eight course. Subjects walked significantly slower using ADs compared to no AD both across the GAITRite and in the figure-of-eight. Measures reflecting gait stability and safety improved with the 4WW but were made worse by some other ADs.

Interactive questioning in critical care during handovers: a transcript analysis of communication behaviours by physicians, nurses and nurse practitioners

Objective Although there is a growing recognition of the importance of active communication behaviours from the incoming clinician receiving a patient handover, there are currently no agreed-upon measures to objectively describe those behaviours. This study sought to identify differences in incoming clinician communication behaviours across levels of clinical training for physicians and nurses. Methods Handover observations were conducted during shift changes for attending physicians, resident physicians, registered nurses and nurse practitioners in three medical intensive care units from July 2011 to August 2012. Measures were the number of interjections from the incoming clinician and the communication mode of those interjections. Each collaborative cross-check, a specific type of interactive question, was subsequently classified by level of assertiveness. Results 133 patient handovers were analysed. Statistical differences were found in both measures. Higher levels of training were associated with fewer interjections, and a higher proportion of interactive questioning to detect erroneous assessments and actions by the incoming provider. All groups were observed to use the least assertive level of a collaborative cross-check, which contributed to misunderstandings. Nurses used less assertive collaborative cross-checks than physicians. Conclusions Differences across clinician type and levels of clinical training were found in both measures during patient handovers. The findings suggest that training could enable physicians and nurses to learn communication competencies during patient handovers which were used more frequently by more experienced practitioners, including interjecting less frequently and using interactive questioning strategies to clarify understanding, and assertively question the appropriateness of diagnoses, treatment plans and prognoses. Accompanying cultural change initiatives might be required to routinely employ these strategies in the clinical setting, particularly for nursing personnel.

Backward walking measures are sensitive to age-related changes in mobility and balance

Many falls occur from backward perturbations or during transitional movements that require a person to turn and step backwards, suggesting that deficits in backward stepping may negatively impact mobility. Previous studies found significant declines in backward walking (BW) spatiotemporal measures in healthy elderly compared to young adults. No studies to date have examined BW performance in middle-aged adults and in elderly with impaired mobility. This study compared spatiotemporal measures of BW and forward walking (FW) in young, middle-aged, and elderly and in elderly fallers and non-fallers; and compared the strength of the relationship between age and BW and FW spatiotemporal measures to determine the utility of BW performance as a clinical tool for examining safety and mobility. BW measures were significantly more impaired in the elderly (n=62) compared to young (n=37) and middle-aged (n=31) adults and age effects were greater in BW than FW. No significant differences were found between young and middle-aged except for base of support in BW. Stronger correlations were found between age and BW measures than between age and FW measures, particularly correlations between age and BW velocity and stride length. Elderly fallers had greater deficits in BW performance than non-fallers. All elderly fallers had BW velocities<.6m/s. Clinicians are encouraged to assess BW, particularly BW velocity, as part of mobility examinations.

Assistive devices alter gait patterns in Parkinson disease: Advantages of the four-wheeled walker

Gait abnormalities are a hallmark of Parkinsons disease (PD) and contribute to fall risk. Therapy and exercise are often encouraged to increase mobility and decrease falls. As disease symptoms progress, assistive devices are often prescribed. There are no guidelines for choosing appropriate ambulatory devices. This unique study systematically examined the impact of a broad range of assistive devices on gait measures during walking in both a straight path and around obstacles in individuals with PD. Quantitative gait measures, including velocity, stride length, percent swing and double support time, and coefficients of variation were assessed in 27 individuals with PD with or without one of six different devices including canes, standard and wheeled walkers (two, four or U-Step). Data were collected using the GAITRite and on a figure-of-eight course. All devices, with the exception of four-wheeled and U-Step walkers significantly decreased gait velocity. The four-wheeled walker resulted in less variability in gait measures and had less impact on spontaneous unassisted gait patterns. The U-Step walker exhibited the highest variability across all parameters followed by the two-wheeled and standard walkers. Higher variability has been correlated with increased falls. Though subjects performed better on a figure-of-eight course using either the four-wheeled or the U-Step walker, the four-wheeled walker resulted in the most consistent improvement in overall gait variables. Laser light use on a U-Step walker did not improve gait measures or safety in figure-of-eight compared to other devices. Of the devices tested, the four-wheeled-walker offered the most consistent advantages for improving mobility and safety.

FACTORS ASSOCIATED WITH LONGER LENGTH OF STAY FOR MENTAL HEALTH EMERGENCY DEPARTMENT PATIENTS

BACKGROUNDnMental health patients can experience long lengths of stay in the emergency department (ED). Reducing boarding times for mental health patients might improve care for all ED patients.nnnOBJECTIVEnThe objective of this study was to identify patient factors that are correlated with extremely long lengths of stay (EL-LOS) for mental health patients in the ED.nnnMETHODSnA retrospective, case-control study compared mental health patients experiencing lengths of stay longer than 24xa0h to those with lengths of stay <24xa0h. The study was conducted at an urban, academic ED and Level I trauma center. Sequential chi-squared tests were used to detect significant differences on the outcome measure. Logistic regression was used to determine factors that made significant contributions to predicting EL-LOS. The outcome measure was patients length of stay in the ED. The factors analyzed were patient demographics, insurance status, day of arrival and departure, placement (admitted locally, admitted remotely, or discharged), chief complaint, and diagnostic category.nnnRESULTSnPatient-level factors associated with EL-LOS were self-pay status, admission to inpatient care, transfer to a remote facility, and suicidal ideation. Admission to inpatient care and self-pay status made significant nonredundant contributions to predicting EL-LOS. In addition, mental health patients arriving on a weekday were significantly more likely to be admitted to inpatient care than those arriving on weekends.nnnCONCLUSIONSnFactors were identified that correlated with long lengths of stay in the ED for mental health patients. Increasing timely access to inpatient beds for mental health patients, in particular by improving access to insurance that covers inpatient psychiatric care and eliminating unique mental health requirements to obtain prior authorization for placement, would likely reduce these patients lengths of stay.

The effect of age on the structural properties of human ribs

Traumatic injury from motor vehicle crashes is a major cause of morbidity and mortality in the United States. The thorax is particularly at risk in motor vehicle crashes and is studied extensively by the injury biomechanics community. Unfortunately, most samples used in such research generally do not include children or the very elderly, despite the common occurrence of thorax injuries at both ends of the age spectrum. Rib fractures in particular, are one of the most common injuries, especially in the elderly, and can greatly affect morbidity, mortality, and quality of life. As the proportion of older adults in the population increases, such age-related fragility fractures will continually grow as a worldwide problem. Additionally, the risk of rib fracture significantly increases with age with confounding deleterious effects. Studies on elderly ribs are not uncommon, however very few studies exist which explore the mechanical properties and behavior of immature human bone, especially of ribs. Previous research identifying rib properties has provided useful information for numerous applications. However, no study has included a comprehensive sample of all ages (pediatric through elderly) in which ribs are tested in the same repeatable set-up. The goal of this study is to characterize differences in rib structural response across the age spectrum. One-hundred forty excised ribs from 70 individuals were experimentally tested in a custom-built pendulum fixture simulating a dynamic frontal impact. The sample includes individuals of ages ranging from six to 99 years old and includes 58 males and 12 females. Reported data include fracture location, displacement in the X and Y directions at fracture (δX, δY), force at fracture (FX), and linear structural stiffness (K). δX and K exhibit a statistically significant linear decrease with age (p<0.0001). FX reveals a trend in which a peak is reached in the young adult years (25-40). Detailed mechanical property data, as provided here, will prove useful for application in computational modeling efforts, which are vital to help prevent injury and to understand injury mechanisms from childhood through old age.

Neuroplasticity Associated With Anterior Cruciate Ligament Reconstruction

STUDY DESIGN: Controlled laboratory study. BACKGROUND: Anterior cruciate ligament (ACL) injury may result in neuroplastic changes due to lost mechanoreceptors of the ACL and compensations in neuromuscular control. These alterations are not completely understood. Assessing brain function after ACL injury and anterior cruciate ligament reconstruction (ACLR) with functional magnetic resonance imaging provides a means to address this gap in knowledge. OBJECTIVE: To compare differences in brain activation during knee flexion/extension in persons who have undergone ACLR and in matched controls. METHODS: Fifteen participants who had undergone left ACLR (38.13 ± 27.16 months postsurgery) and 15 healthy controls matched on age, sex, height, mass, extremity dominance, education level, sport participation, and physical activity level participated. Functional magnetic resonance imaging data were obtained during a unilateral knee motor task consisting of repeated cycles of knee flexion and extension. RESULTS: Participants who had undergone ACLR had increased activation in the contralateral motor cortex, lingual gyrus, and ipsilateral secondary somatosensory area and diminished activation in the ipsilateral motor cortex and cerebellum when compared to healthy matched controls. CONCLUSION: Brain activation for knee flexion/extension motion may be altered following ACLR. The ACLR brain activation profile may indicate a shift toward a visual‐motor strategy as opposed to a sensory‐motor strategy to engage in knee movement. LEVEL OF EVIDENCE: Cohort, level 3.

Impact of tetrabenazine on gait and functional mobility in individuals with Huntington's disease

Chorea may contribute to balance problems and walking difficulties that lead to higher fall rates in individuals with Huntingtons disease (HD). Few studies have examined the effects of tetrabenazine (TBZ), an anti-choreic drug, on function and mobility in HD. The purpose of this study was to compare: 1) gait measures in forward walking, 2) balance and mobility measures, and 3) hand and forearm function measures on and off TBZ. We hypothesized that use of TBZ would improve gait, transfers and hand and forearm function. Eleven individuals with HD on stable doses of TBZ were evaluated while off medication and again following resumption of medication. Significant improvements were found on the Unified Huntingtons Disease Rating Scale (UHDRS) motor scores, Tinetti Mobility Test (TMT) total (t=4.20, p=0.002) and balance subscale (t=-4.61, p=0.001) scores, and the Five Times Sit-to-Stand test (5TSST, t=3.20, p=.009) when on-TBZ compared to off-TBZ. Spatiotemporal gait measures, the Six Condition Romberg test, and UHDRS hand and forearm function items were not changed by TBZ use. Improved TMT and 5TSST performance when on drug indicates that TBZ use may improve balance and functional mobility in individuals with HD.

AGE AND SEX ALONE ARE INSUFFICIENT TO PREDICT HUMAN RIB STRUCTURAL RESPONSE TO DYNAMIC A-P LOADING

Thoracic injuries from motor vehicle crashes (MVCs) are common in children and the elderly and are associated with a high rate of mortality for both groups. Rib fractures, in particular, are linked to high mortality rates which increase with the number of fractures sustained. Anthropomorphic test devices (ATDs) and computational models have been developed to improve vehicle safety, however these tools are constructed based on limited physical datasets. To-date, no study has explored variation of rib structural properties across the entire age spectrum with data obtained using the same experimental methodology to allow for comparison. One-hundred eighty-four ribs from 93 post mortem human subjects (PMHS) (70 male, 23 female; ages 4-99) were subjected to dynamic bending tests simulating a frontal impact to the thorax. Structural mechanical properties were calculated and a multi-level statistical model quantified the sample variance as explained by age and sex. Displacement (δX), peak force (Fpeak), linear structural stiffness (K), energy absorption to fracture (Utot), and plastic properties including post-yield energy absorption (UPl), plastic displacement (δPl), and the ratio of elastic to secant stiffness (K-ratio) all showed negative relationships with age, while only Fpeak, K, and Utot were dependent on sex. Despite these relationships being statistically significant, only 7-39% of variance is explained by age and only 3-17% of variance is explained by sex. This demonstrates that variability in bone properties is more complex than simply chronological age- and sex-dependence and should be explored in the context of biological mechanisms instead.

The National Institutes of Health Stroke Scale Lacks Validity in Chronic Hemiparetic Stroke.

BACKGROUNDnThe National Institutes of Health Stroke Scale (NIHSS) is purported to be associated with long-term outcomes. This study determined the concurrent validity of the NIHSS with the Stroke Impact Scale (SIS), a previously validated measure of health status in chronic stroke survivors.nnnMETHODSnThe NIHSS and the SIS were administered to 147 subjects before participation in a multicenter, randomized, controlled trial. A Spearmans rho was used to determine correlations between NIHSS total score and (1) SIS physical dimension scores, (2) SIS overall perception of recovery scores, and (3) the SIS activities and independent activities of daily living (ADL/IADL) scores. SIS score variation and medians between subjects who scored a zero versus a nonzero on the NIHSS was also assessed.nnnRESULTSnThere was no association between total NIHSS scores and SIS physical dimension scores, SIS overall perception of recovery scores, and SIS ADL/IADL scores (P = -.036, P = .782; P = -.039, P = .640; P = -.054, P = .520; respectively). Lastly, significant variation and similar median scores on the SIS were found between those scoring a zero on the NIHSS versus those who did not score a zero.nnnCONCLUSIONSnThe NIHSS has no association with health status in chronic stroke and lacks association with measures of impairment and functional limitation. From these findings, we conclude that the NIHSS has poor validity to discern long-term poststroke outcomes and is not associated with health status. Because of possible limitation in the NIHSSs ability to accurately determine outcomes in this population, we recommend restriction of its use to the acute stage of recovery.