Does the setting matter? Observing wheelchair transfers across different environmental conditions

The setting in which wheelchair transfers are performed can affect difficulty and the risks associated with completion. This article presents results from an observational study involving 13 wheelchair users performing independent transfers across four settings. The aim is to understand how the environment affects how different types of independent transfers are performed. Descriptive analysis was performed alongside an objective assessment using the Transfer Assessment Instrument (TAI). The perceived difficulty reported after each transfer was also collected. Two participants exhibited radically different transferring techniques in different scenarios. Additionally, the transferring scenario was found to significantly affect the perceived difficulty of sitting transfers (toilet 2.17 ± .88; bed 1.47 ± .65, p = .001; car 1.63 ± .82, p = .012) and standing transfers (car 3.5 ± .71; bed 1 ± 0, p = .03; toilet 1 ± 0, p = .03), and the TAI score attributed to sitting pivot with use of a transfer board (couch 4.3 ± .88; bed 6.93 ± 1.29, p = .022; car 7.13 ± 1.32, p = .018) . Overall, environmental constraints, can lead to major technique changes and, more often, to different positioning of hands and feet which could impact the transfer’s biomechanics

Use of a Low Cost, Chest-Mounted Accelerometer to Evaluate Transfer Skills of Wheelchair Users During Everyday Activities

BACKGROUND: Transfers are an important skill for many wheelchair users. However, they have also been related to the risk of falling or developing upper limb injuries. Transfer abilities are usually evaluated in clinical settings or biomechanics laboratories and these methods of assessment are poorly suited to evaluation in real and unconstrained world settings where transfers take place. OBJECTIVE: The objective of this paper is to develop a strategy to enable transfer quality evaluation and improve the predictive accuracy of transfer detection using a single wearable low cost accelerometer. METHODS: We collected data from nine wheelchair users wearing tri-axial accelerometer on their chest while performing transfers to and from car seats and home furniture. We then extracted significant features from accelerometer data based on biomechanical considerations and previous relevant literature and used machine learning algorithms to evaluate the performance of wheelchair transfers and detect their occurrence from a continuous time series of data. RESULTS: Results show that the best predictive accuracy for Automatic Transfer Quality Evaluation was obtained with Support Vector Machine (SVM) classifiers when determining use of head-hip relationship (75.93%) and smoothness of landing (79.62%), when the start and end of the transfer are known. Automatic Transfer Detection reaches an accuracy of 87.8% using Multinomial Logistic Regression (MLR) classifiers, which is in line with the state of the art in this context. However, we achieve these results using only a single sensor and collecting data in a more ecological manner. CONCLUSIONS: The use of a single chest-placed accelerometer shows a predictive accuracy of over 75% for algorithms applied independently to both transfer evaluation and monitoring. This points to the opportunity for designing ubiquitous technology for personalized skill development interventions targeting wheelchair users. However, monitoring transfers still requires the use of external inputs or extra sensors to identify start and end of the transfer, which are needed to perform an accurate evaluation

The Influence of Series Elastic Bands on Energy During Acceleration Training

Please refer to the pdf version of the abstract located adjacent to the title

Hybrid Equation/Agent-Based Model of Ischemia-Induced Hyperemia and Pressure Ulcer Formation Predicts Greater Propensity to Ulcerate in Subjects with Spinal Cord Injury

Pressure ulcers are costly and life-threatening complications for people with spinal cord injury (SCI). People with SCI also exhibit differential blood flow properties in non-ulcerated skin. We hypothesized that a computer simulation of the pressure ulcer formation process, informed by data regarding skin blood flow and reactive hyperemia in response to pressure, could provide insights into the pathogenesis and effective treatment of post-SCI pressure ulcers. Agent-Based Models (ABM) are useful in settings such as pressure ulcers, in which spatial realism is important. Ordinary Differential Equation-based (ODE) models are useful when modeling physiological phenomena such as reactive hyperemia. Accordingly, we constructed a hybrid model that combines ODEs related to blood flow along with an ABM of skin injury, inflammation, and ulcer formation. The relationship between pressure and the course of ulcer formation, as well as several other important characteristic patterns of pressure ulcer formation, was demonstrated in this model. The ODE portion of this model was calibrated to data related to blood flow following experimental pressure responses in non-injured human subjects or to data from people with SCI. This model predicted a higher propensity to form ulcers in response to pressure in people with SCI vs. non-injured control subjects, and thus may serve as novel diagnostic platform for post-SCI ulcer formation. © 2013 Solovyev et al

How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers

Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program

Sensing Senses: Tactile Feedback for the Prevention of Decubitus Ulcers

Decubitus ulcers, also known as pressure sores, is a major problem in health care, in particular for patients with spinal cord injuries. These patients cannot feel the discomfort that would urge healthy people to change their posture. We describe a system that uses a sensor mat to detect problematic postures and provides tactile feedback to the user. The results of our preliminary study with healthy subjects show that the tactile feedback is a viable option to spoken feedback. We envision the system being used for rehabilitation games, but also for everyday Decubitus ulcers prevention