Views of wheelchair users and caregivers regarding a passive safety monitoring system for electric powered wheelchair operators with cognitive impairment.

The opinions of cognitively intact current wheelchair users and their professional caregivers were solicited to explore acceptability of the concept of a passive electric wheelchair-mounted movement monitor to track driving safety and cognitive impairment. Two focus groups of electric wheelchair users (N = 9), and two focus groups of staff caregivers (N = 8) were conducted at a congregate care facility. Participants also completed a questionnaire examining their perceptions of the concept. The results indicated most wheelchair users and staff caregivers were receptive to the idea of a passive safety monitoring system for wheelchairs to detect cognitive impairment. Three main and interrelated themes emerged regarding how the device could promote safety, how such a system might infringe upon the users' autonomy, and how and to whom the cognitive state information should be communicated. Legal, training, and marketing issues reflected similar concerns over balancing autonomy with safety issues. If successfully addressed, it appears there would be support for the device's use not only for older adults in institutional settings, but perhaps also among community living younger and older adults. A passive safety monitoring system for wheelchairs is acceptable to wheelchair users and can be successfully marketed if developers balance autonomy and safety concerns.

Movement Path Tortuosity Predicts Compliance With Therapeutic Behavioral Prompts in Patients With Traumatic Brain Injury.

OBJECTIVE: Rehabilitation of patients with traumatic brain injury typically includes therapeutic prompts for keeping appointments and adhering to medication regimens. Level of cognitive impairment may significantly affect a traumatic brain injury victim's ability to benefit from text-based prompting. We tested the hypothesis that spatial disorientation as measured by movement path tortuosity during ambulation would be associated with poorer compliance with automated prompts by veterans actively being treated for traumatic brain injury. SETTING: Clinical polytrauma center. PARTICIPANTS: Ten (1 female) veteran patients mean age = 35.4 (SD = 12.4) years. DESIGN: Small group correlational study without random assignment. MAIN MEASURES: Fractal Dimension, a measure of movement path tortuosity derived from a GPS logging device used to record casual outdoor ambulation at the start of the study. Compliance with smart home machine-generated therapeutic prompts received during rehabilitation at the James A. Haley Veterans Administration Hospital Polytrauma Transitional Rehabilitation Program. A patient was compliant with a prompt if they transited from where the prompt was presented to the prescribed destination (both within the Polytrauma Transitional Rehabilitation Program) within 30 minutes. Noncompliance was failure to appear at the destination within the allotted time. RESULTS: Fractal dimension was significantly inversely related to overall prompt compliance (r = -0.603, n = 10, P = .032; 1-tailed). CONCLUSIONS: The findings support the hypothesis that increased spatial disorientation adversely impacts compliance with automated prompts throughout therapy. The results are consistent with previous studies linking elevated path tortuosity to cognitive impairment and increased risk for falls in assisted living facility residents.

Decreased Movement Path Tortuosity Is Associated With Improved Functional Status in Patients With Traumatic Brain Injury.

OBJECTIVE: To determine if movement path tortuosity in everyday ambulation decreases in Veterans being treated in a residential setting for traumatic brain injury. Elevated path tortuosity is observed in assisted living facility residents with cognitive impairment and at risk for falls, and tortuosity may decrease over the course of cognitive rehabilitation received by the Veterans. If observed, decreased tortuosity may be linked to improved clinical outcomes. DESIGN: Longitudinal observational study without random assignment. SETTING: Veterans Affairs Medical Center inpatient residential polytrauma treatment facility. PATIENTS: Twenty-two Veterans enrolled in a postacute predischarge residential polytrauma treatment facility. INTERVENTIONS: None, observation-only. MAIN OUTCOME MEASURE: Mayo-Portland Adaptability Index-4, and movement path tortuosity measured by Fractal Dimension (Fractal D). Fractal D was obtained continuously from an indoor movement tracking system primarily used to provide machine-generated prompts and reminders to facilitate activities of daily living. Patients were deemed "responders" (N = 10) if a significant linear decline in Fractal D occurred over the course of treatment, or nonresponders (N = 12) if no significant decline was observed. RESULTS: Responders had lower discharge Mayo-Portland Adaptability Inventory scores (mean = 32.6, SD = 9.53) than non-responders (mean = 39.5, SD = 6.02) (F = 2.07, df = 20, P = .05). Responders and nonresponders did not differ on initial injury severity or other demographic measures. CONCLUSIONS: Fractal D, a relatively simple measure of movement path tortuosity can be linked to functional recovery from traumatic brain injury.

Elevated movement path tortuosity in voluntary outdoor ambulation in community-dwelling veterans with a history of traumatic brain injury.

OBJECTIVE: In comparison to veterans without a history of traumatic brain injury (TBI), we hypothesized that veterans with past TBI would have slower walking speed and more path tortuosity, TBI symptoms, problems with spatial orientation, and poorer executive function. SETTING: Community nonclinical. PARTICIPANTS: Seventeen males (mean age of 37.2 years) reporting prior TBI and 20 non-TBI (mean age of 42.9 years). The number of years separating date of discharge and testing was 10.8 and 15.4 for the TBI and non-TBI groups, respectively. DESIGN: Small 2 groups without random assignment. MAIN MEASURES: Brief Traumatic Brain Injury Screen, Trail Making Test-B, Clock Drawing Test, walking speed, and distance and path tortuosity in 30 minutes of voluntary outdoor walking wearing a small Global Positioning Systems recorder. RESULTS: Those with TBI reported 4 Brief Traumatic Brain Injury Screen symptoms versus 0.4 for controls (F = 49.1; df = 1,35; P < .001) but did not differ on Trail Making Test-B or the Clock Drawing Test. Veterans with TBI walked shorter distances, 2.33 km versus 2.84 km (F = 4.8; df = 1,35; P < .05), and had greater path tortuosity (fractal D of 1.22 vs 1.15; F = 3.5; df = 1,35; P < .05) but did not differ on travel speed or time spent walking. CONCLUSIONS: Traumatic brain injury has persistent symptomatic effects and significantly affects ambulation and spatial orientation years after the event. These findings corroborate and extend observations linking cognitive impairment and ambulation.

Path tortuosity in everyday movements of elderly persons increases fall prediction beyond knowledge of fall history, medication use, and standardized gait and balance assessments.

OBJECTIVES: We hypothesized that variability in voluntary movement paths of assisted living facility (ALF) residents would be greater in the week preceding a fall compared with residents who did not fall. DESIGN: Prospective, observational study using telesurveillance technology. SETTING: Two ALFs. PARTICIPANTS: The sample consisted of 69 older ALF residents (53 female) aged 76.9 (SD ± 11.9 years). MEASUREMENT: Daytime movement in ALF common use areas was automatically tracked using a commercially available ultra-wideband radio real-time location sensor network with a spatial resolution of approximately 20 cm. Movement path variability (tortuosity) was gauged using fractal dimension (fractal D). A logistic regression was performed predicting movement related falls from fractal D, presence of a fall in the prior year, psychoactive medication use, and movement path length. Fallers and non-fallers were also compared on activities of daily living requiring supervision or assistance, performance on standardized static and dynamic balance, and stride velocity assessments gathered at the start of a 1-year fall observation period. Fall risk due to cognitive deficit was assessed by the Mini Mental Status Examination (MMSE), and by clinical dementia diagnoses from participant's activities of daily living health record. RESULTS: Logistic regression analysis revealed odds of falling increased 2.548 (P = .021) for every 0.1 increase in fractal D, and having a fall in the prior year increased odds of falling by 7.36 (P = .006). There was a trend for longer movement paths to reduce the odds of falling (OR .976 P = .08) but it was not significant. Number of psychoactive medications did not contribute significantly to fall prediction in the model. Fallers had more variable stride-to-stride velocities and required more activities of daily living assistance. CONCLUSIONS: High fractal D levels can be detected using commercially available telesurveillance technologies and offers a new tool for health services administrators seeking to reduce falls at their facilities.