Fall prevention intervention technologies: A conceptual framework and survey of the state of the art

In recent years, an ever increasing range of technology-based applications have been developed with the goal of assisting in the delivery of more effective and efficient fall prevention interventions. Whilst there have been a number of studies that have surveyed technologies for a particular sub-domain of fall prevention, there is no existing research which surveys the full spectrum of falls prevention interventions and characterises the range of technologies that have augmented this landscape. This study presents a conceptual framework and survey of the state of the art of technology-based fall prevention systems which is derived from a systematic template analysis of studies presented in contemporary research literature. The framework proposes four broad categories of fall prevention intervention system: Pre-fall prevention; Post-fall prevention; Fall injury prevention; Cross-fall prevention. Other categories include, Application type, Technology deployment platform, Information sources, Deployment environment, User interface type, and Collaborative function. After presenting the conceptual framework, a detailed survey of the state of the art is presented as a function of the proposed framework. A number of research challenges emerge as a result of surveying the research literature, which include a need for: new systems that focus on overcoming extrinsic falls risk factors; systems that support the environmental risk assessment process; systems that enable patients and practitioners to develop more collaborative relationships and engage in shared decision making during falls risk assessment and prevention activities. In response to these challenges, recommendations and future research directions are proposed to overcome each respective challenge.The Royal Society, grant Ref: RG13082

A serious game for the learning of vibrotactile feedbacks presented under the foot : how many and how fast?

Vision and auditory channels are often used to convey information quickly. Knowing that hearing and vision are generally loaded with plenty of stimuli, the use of touch as an alternative medium of communication could unload those senses. Although many studies have been conducted on hapic icons or tactile icons, few of them have focused on the foot as a medium of communication. This paper particularly investigate the maximum number of vibrotactile messages that could be memorized when displayed under the foot. The method is based on a daily training wrapped in a serious game. In the latter, the avatar must be led to different locations through risky path. Risky events are displayed along the route through vibrotactile feedbacks, which have to be identified by the player. A preliminary experiment shows the usability of this serious game for learning a large number of vibrotactile stimuli

Measuring operator’s pain : toward evaluating Musculoskeletal disorder at work

Musculoskeletal disorders (MSDs) have affected an increasing number of people in the active general population. In this perspective, we developed a measuring tool taking muscle activities in certain regions of the body, standing posture taking the center of pressure under the feet and feet positions. This tool also comprises an instrumented helmet containing an electroencephalogram (EEG) to measure brain activity, and an accelerometer reporting the movements of the head. Then, our tool comprises both non-invasive instrumented insole and safety helmet. Moreover, the same tool measures muscular activities in specific regions of the body using an electromyogram (EMG). The aim is to combine all the data in order to identify consistent patterns between brain activity, postures, movements and muscle activity, and then, understand their connection to the development of MSDs. This paper presents three situations reported to be a risk for MSDs and an analysis of the signals is presented in order to differentiate adequate or abnormal posture

An Efficient Home-Based Risk of Falling Assessment Test Based on Smartphone and Instrumented Insole

The aim of this study is to improve and facilitate the methods used to assess risk of falling among older people at home. We propose an automatic version of One-Leg Standing (OLS) test for risk of falling assessment by using a Smartphone and an instrumented insole. For better clinical assessment tests, this study focuses on exploring methods to combine the most important parameters of risk of falling into a single score. Twenty-three volunteers participated in this study for evaluating the effectiveness of the proposed system which includes eleven elderly participants: seven healthy elderly (67.16 ± 4.24 years), four Parkinson disease (PD) subjects (70 ± 12.73 years); and twelve healthy young adults (28.27 ± 3.74 years). Our work suggests that there is an inverse relationship between OLS score proposed and risk of falling. Proposed instrumented insole and application running on Android could be useful at home as a diagnostic aid tool for analyzing the performance of elderly people in OLS test

Home-based risk of falling assessment test using a closed-loop balance model

The aim of this study is to improve and facilitate the methods used to assess risk of falling at home among older people through the computation of a risk of falling in real time in daily activities. In order to increase a real time computation of the risk of falling, a closed-loop balance model is proposed and compared with One-Leg Standing Test (OLST). This balance model allows studying the postural response of a person having an unpredictable perturbation. Twenty-nine volunteers participated in this study for evaluating the effectiveness of the proposed system which includes seventeen elder participants: ten healthy elderly (68.4 ± 5.5 years), seven Parkinson’s disease (PD) subjects (66.28 ± 8.9 years), and twelve healthy young adults (28.27 ± 3.74 years). Our work suggests that there is a relationship between OLST score and the risk of falling based on center of pressure (COP) measurement with four low cost force sensors located inside an instrumented insole, which could be predicted using our suggested closed-loop balance model. For long term monitoring at home, this system could be included in a medical electronic record and could be useful as a diagnostic aid tool

Response time to a vibrotactile stimulus presented on the foot at rest and during walking on different surfaces

This study investigates the simple reaction time (SRT) and response time (RT) to a vibrotactile stimulus presented on two body locations at the lower extremity of the foot on different types of surface during walking. We determined RTs while walking on Concrete, Foam, Sand, and gravel surface. Also, for RT, we evaluated two vibrotactile stimulus (VS) locations on the lower extremity: the ankle (AL) and under the foot plantar (FP). A total of 21 young adult participants (n = 21), aged mean 24 ± 2.9 years, took part in a two-session experiment with two main conditions (at rest and while walking on four types of surface). The control session included 2016 repeated measures, with one-way and two-way ANOVA analyses. The findings have consistently revealed slowness of RT to VS, in particular on sand and gravel surface. In addition, we found that body location has a significant effect on RT in certain surfaces. These results showed that RTs increased with environment changes during the performance of dual tasks

Exploitation of haptic renderings to communicate risk levels of falling

Falls represent a major cause of injury that could lead to death. This observation is even more accentuated in the elderly. Indeed, with aging comes some deterioration (gait disturbances, balance disorders, and sensory motor impairments) that may lead to falls. The research project presented in this thesis is focused on the problem of reducing the risk level of falling. This study proposes a solution for the communication of haptic information to reduce the risk of falling. This solution is part of the design of a haptic communication system in a controlled environment. This new system introduces the notion of haptic perception through the communication of information by touch using the foot, which the literature does not generally mention. For the design of this system, we first studied the use of tactile stimuli to evaluate the possibility of communicating a risk level through a haptic modality. Then, having hypothesized that some factors could influence the communication of stimuli representing the risk levels of falling, we conducted a second study to evaluate the effect of auditory disturbances during the communication of these stimuli. Third, to determine whether the user had the necessary time to act after the perception of the risk level, we analyzed a variation of the simple reaction time when walking on different types of soil. These results encouraged us to do a fourth assessment of reaction time using a new device coupled with a smartphone that can be positioned at different locations on the body. Several experiments have been done to validate each of the steps. With this, we can now communicate a risk level of falling to users through the haptic channel using an active device and easily differentiable stimuli. In addition, we can evaluate auditory factors during such a haptic perception. Finally, we can evaluate the physiological characteristics of the users (response time) while seated and while walking on different types of soil. Les chutes représentent une cause majeure de blessures pouvant entraîner la mort. Cette observation est encore plus accentuée chez les personnes âgées. En effet, avec le vieillissement, certaines détériorations (troubles de la démarche, troubles de l’équilibre, troubles sensorimoteurs) peuvent entraîner des chutes. Le projet de recherche présenté dans cette thèse fait partie du problème de la réduction du risque de chute. En particulier, cette étude propose une solution au problème de la réduction du risque de chute par la perception haptiques. Cette solution intègre la conception d’un système de communication haptique dans un environnement contrôlé. Ce nouveau système introduit la notion de perception haptique à travers la communication de l’information par le toucher avec le pied, que la littérature ne mentionne généralement pas. Pour cela nous avons d’abord étudié l’utilisation de stimuli tactiles pour évaluer la possibilité de communiquer un niveau de risque par la modalité haptique. Puis, ayant émis l’hypothèse que certains facteurs pourraient influencer la communication de ces stimuli, nous avons mené une deuxième étude pour évaluer l’impact des perturbations auditives lors de la perception haptique du niveau de risque. Troisièmement, afin de savoir si l’utilisateur avait le temps nécessaire pour agir après la perception du niveau de risque, nous avons analysé la variation du temps de réaction simple en marchant sur différents types de sols. Les résultats obtenus dans cette dernière étude nous ont motivé à faire une quatrième évaluation du temps de réaction mais en utilisant un nouveau dispositif couplé à un smartphone qui peut être positionné à différents endroits du corps. Plusieurs expériences ont été réalisées pour valider chacune des étapes. Avec toutes ces études, nous pouvons maintenant communiquer aux utilisateurs un niveau de risque à travers le canal haptique en utilisant un dispositif actif et des stimuli facilement différentiables. En outre, nous pouvons évaluer les facteurs externes (auditifs) au cours d’une telle perception haptique. Enfin, nous pouvons évaluer les caractéristiques physiologiques des utilisateurs (temps de réponse) en position assise et en marchant sur différents types de sols

A Review on Fall Prediction and Prevention System for Personal Devices: Evaluation and Experimental Results

Injuries due to unintentional falls cause high social cost in which several systems have been developed to reduce them. Recently, two trends can be recognized. Firstly, the market is dominated by fall detection systems, which activate an alarm after a fall occurrence, but the focus is moving towards predicting and preventing a fall, as it is the most promising approach to avoid a fall injury. Secondly, personal devices, such as smartphones, are being exploited for implementing fall systems, because they are commonly carried by the user most of the day. This paper reviews various fall prediction and prevention systems, with a particular interest to the ones that can rely on the sensors embedded in a smartphone, i.e., accelerometer and gyroscope. Kinematic features obtained from the data collected from accelerometer and gyroscope have been evaluated in combination with different machine learning algorithms. An experimental analysis compares the evaluated approaches by evaluating their accuracy and ability to predict and prevent a fall. Results show that tilt features in combination with a decision tree algorithm present the best performance

A Smart Safety Helmet using IMU and EEG sensors for analysis of worker’s fatigue

It is known that head gesture and mental states can reflect some human behaviors related to a risk of accident when using machine-tools. The research works presented in this paper aim to reduce the number of injury and thus increase worker safety. Instead using camera, this paper presents a Smart Safety Helmet (SSH) in order to track head gestures and mental states of worker able to recognize anomalous behavior. Information extracted from SSH is used for computing risk level of accident (a safety level) for preventing and reducing injury or accidents. The SSH system is an inexpensive, non-intrusive, non-invasive, and non-vision-based system, which consists of 9DOF Inertial Measurement Unit (IMU) and dry EEG electrodes. A haptic device, such as vibrotactile motor, is integrated to the helmet in order to alert the operator when computed risk level (fatigue, high stress or error) reach a threshold. Once the risk level of accident breaks the threshold, a signal will be sent wirelessly to stop the relevant machine tool or process

Lower limb injury prevention in the New Zealand Army : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD) in Sport and Exercise at Massey University, Wellington, New Zealand

Background The mobility of the New Zealand Defence Force (NZDF) and its ability to deploy personnel at short notice is compromised by the high number of musculoskeletal injuries, particularly to the lower limbs. Literature searches indicated footwear may be the issue. The aim of this research is to examine the extent of the problem, which injuries and anatomical structures are most affected, the aetiology involved, and finally, the effects of a possible remedial intervention. Methodology Information from 11 years of NZDF injury records were examined. Chi square analysis was used to determine most affected joint(s), injury type and activities (sporting or military). The ankle joint appeared most vulnerable to injury, particularly during sporting or military activities involving running. Traumatic ankle sprains and strains were the most prolific injuries and this occurred when not wearing the military boot. This information was used to determine the subsequent investigations of the biomechanical and neurological aetiology underlying habitual boot-wear that might give rise to these injuries. Ankle range of motion (ROM), endurance strength, power and fatigue were measured using an isokinetic dynamometer (Biodex) in new recruits and repeated after one year of military boot-wear. Muscle activation of tibialis anterior and both the medial and lateral gastrocnemius were also measured during quiet standing on a force platform to measure postural sway. The same measures of aetiology were conducted on 65 habitual boot wearing regular force military male personnel pre and post-introduction of a low-cut flexible shoe. These 65 personnel all had served greater than two years in the NZDF. At 10 weeks, the effects of pre- and post- flexible shoe wear were measured to determine if the effects of habitual boot-wear could be reversed. Results After 12 months of habitual military boot-wear, ankle ROM was decreased in all planes of movement, endurance strength and power were significantly reduced and fatigue onset increased after one year of boot-wear. Muscle activation was increased in tibialis anterior and both the medial and lateral gastrocnemius, which coincided with significantly increased sway patterns indicating poor postural stability. After 10 weeks of transitioning from habitual military boot-wear to a flexible shoe, ankle ROM, and strength significantly increased, while fatigue, muscle activation and postural sway decreased. Conclusion Chronic military boot-wear causes mal-adaptations and is associated with the high number of ankle injuries in the NZDF, however the effects can be reversed. It was advised that when not on military manoeuvres that personnel wear a low-cut flexible garrison shoe