Lower Extremity Assistive Devices (LEADs): A Contemporary Literature Review.

Lower extremity ambulatory assistive devices (LEADs) are important augments that provide mobility and stability when weightbearing is restricted in the setting of injury, surgery, or balance disorders. In order to optimize patient safety and function when prescribing these devices, it is essential for the orthopaedic surgeon to have a firm understanding of their specific indications, proper fitting, energy demand, biomechanical advantages, and potential complications. Comprehension of normal gait cadence, identification of the functional deficit present and knowledge of available options will assist in safely prescribing the proper device. Over the last decade, newer alternatives to traditional LEADs (canes, crutches, walkers) have become available, including the rolling knee scooter and hands-free single crutch. These have been developed to improve mobility and independence; however, it is necessary to appreciate their limitations when prescribing them to patients. This review will provide an update on normal and pathologic gait biomechanics as well as the most common types of LEADs currently available to the orthopaedic surgeon, their indications, important considerations, proper fitting, associated energy expenditure, and complications.

Evaluating Gait Stability and Muscle Activation in Different Hand Holding Conditions Using the Robotic Walker-mTPAD.

While walkers are used as mobility aids for different gait impairments, little is known about the factors that affect the performance of such aids. Therefore, we investigated the impact of arm-holding conditions on gait stability and muscle activation. We used surface electromyography (sEMG) sensors on specific arm and leg muscles while the users took laps with a robotic walker, the mobile Tethered Pelvic Assist Device (mTPAD), on an instrumented mat. Eleven participants without gait disorders walked with and without a 10% body weight (BW) force applied on the pelvis in the following three configurations: (i) while gripping the walker's frame, (ii) while using an armrest with their arms at a 90∘ angle, and (iii) while using an armrest with their arms at a 130∘ angle for 5 min each. Our results showed that when applying a force, the users changed their gait to increase stability. We also discovered differences in muscle activation based on the user's specific arm conditions. Specifically, the 130∘ condition required the least muscle activation, while gripping the walker's frame increased specific muscle activation compared to 90∘ and 130∘. This study is the first to evaluate how arm-holding and external loading conditions alter gait and muscle activations using the mTPAD.

A qualitative exploration of adherence to wearing removable cast walkers in patients with diabetic foot ulcers.

OBJECTIVE: To explore adherence to wearing removable cast walkers (RCWs) among patients with diabetic foot ulcers (DFUs). METHOD: A qualitative study was conducted by interviewing patients with active DFUs and using knee-high RCWs as their offloading treatment. The interviews were undertaken at two diabetic foot clinics in Jordan, using a semi-structured guide. Data were analysed through content analysis by developing main themes and categories. RESULTS: Following interviews with 10 patients, two main key themes with a total of six categories were identified: theme 1-reporting of adherence levels was inconsistent, included two categories: i) a belief in achieving optimal adherence, and ii) non-adherence was often reported indoors; and theme 2-adherence was a consequence of multiple psychosocial, physiological and environmental factors, which included four categories: i) specific offloading knowledge or beliefs influenced adherence; ii) severity of foot disease influenced adherence; iii) social support benefitted adherence; and iv) physical features of RCWs (the usability of the offloading device) impacted adherence. CONCLUSION: Patients with active DFUs reported inconsistent levels of adherence to wearing RCWs which, after deeper investigation, seemed to be due to participants' misperceptions of the optimal adherence. Adherence to wearing RCWs also seemed to be impacted by multiple psychosocial, physiological and environmental factors.

Offloading effects of a removable cast walker with and without modification for diabetes-related foot ulceration: a plantar pressure study.

BACKGROUND: Removable cast walkers (RCWs), with or without modifications, are used to offload diabetes-related foot ulcers (DRFUs), however there is limited data relating to their offloading effects. This study aimed to quantify plantar pressure reductions with an RCW with and without modification for DRFUs. METHODS: This within-participant, repeated measures study included 16 participants with plantar neuropathic DRFUs. Walking peak plantar pressures at DRFU sites were measured for four conditions: post-operative boot (control condition), RCW alone, RCW with 20 mm of felt adhered to an orthosis, and RCW with 20 mm of felt adhered to the foot. RESULTS: Compared to the control condition, the greatest amount of peak plantar pressure reduction occurred with the RCW with felt adhered to the foot (83.1% reduction, p < .001). The RCW with felt adhered to the foot also offered greater peak plantar pressure reduction than the RCW alone (51.3%, p = .021) and the RCW with felt adhered to an orthosis (31.4%, p = .009). CONCLUSION: The largest offloading effect recorded was with the RCW with felt adhered to the foot. High-quality randomised trials are now needed to evaluate the effectiveness of this device for healing DRFUs.

The Validity and Reliability of Self-Reported Adherence to Using Offloading Treatment in People with Diabetes-Related Foot Ulcers.

Adherence to using offloading treatment is crucial to healing diabetes-related foot ulcers (DFUs). Offloading adherence is recommended to be measured using objective monitors. However, self-reported adherence is commonly used and has unknown validity and reliability. This study aimed to assess the validity and reliability of self-reported adherence to using removable cast walker (RCW) offloading treatment among people with DFUs. Fifty-three participants with DFUs using RCWs were included. Each participant self-reported their percentage adherence to using their RCW of total daily steps. Participants also had adherence objectively measured using dual activity monitors. After one week, a subset of 19 participants again self-reported their percentage adherence to investigate test-retest reliability. Validity was tested using Pearson's r and Bland-Altman tests, and reliability using Cohen's kappa. Median (IQR) self-reported adherence was greater than objectively measured adherence (90% (60-100) vs. 35% (19-47), p < 0.01). There was fair agreement (r = 0.46; p < 0.01) and large 95% limits of agreement with significant proportional bias (ß = 0.46, p < 0.01) for validity, and minimal agreement for test-retest reliability (K = 0.36; p < 0.01). The validity and reliability of self-reported offloading adherence in people with DFU are fair at best. People with DFU significantly overestimate their offloading adherence. Clinicians and researchers should instead use objective adherence measures.

Simulation study on assist-as-needed control of a rehabilitation robotic walker.

BACKGROUND: Along with China entering an aging society, the percentage of people that over 60 will reach 34.9% in 2050, resulted in a significant increase in stroke patients. OBJECTIVE: This paper proposes a rehabilitation robotic walker for walking assistance during the daily life, and a control method for the motor relearning during the gait training. The walker consists of an omni-directional mobile platform (OMP) which ensures the walker can move on the ground, a body weight support system (BWS) which is capable of providing the desired unloading force, and a pelvic assist mechanism (PAM) to provide the user with four degrees of freedom and avoid the rigid impact. The study goal is to gain a better understanding of the assist-as-needed control strategy during the gait training. METHODS: For the man-machine interaction control, the assist-as-needed control strategy is adopted to guide the users' motions and improve the interaction experience. To build the force field in the three-dimensional space, the dynamics of the system is derived to increase the accuracy of force control. RESULTS: The simulation results show that the force field around the motion trajectory was generated in the three-dimensional space. In order to understand the force field, we designed the simulation on sagittal plane and the controller can generate the appropriate force field. The preliminary experiment results were consistent with the simulation results. CONCLUSION: Based on the mathematical simulation and the preliminary test, the results demonstrate that the proposed system can provide the guide force around the target trajectory, the accuracy of force control still remains to be improved.

Reimagining robotic walkers for real-world outdoor play environments with insights from legged robots: a scoping review.

PURPOSE: For children with mobility impairments, without cognitive delays, who want to participate in outdoor activities, existing assistive technology (AT) to support their needs is limited. In this review, we investigate the control and design of a selection of robotic walkers while exploring a selection of legged robots to develop solutions that address this gap in robotic AT. METHOD: We performed a comprehensive literature search from four main databases: PubMed, Google Scholar, Scopus, and IEEE Xplore. The keywords used in the search were the following: "walker", "rollator", "smart walker", "robotic walker", "robotic rollator". Studies were required to discuss the control or design of robotic walkers to be considered. A total of 159 papers were analyzed. RESULTS: From the 159 papers, 127 were excluded since they failed to meet our inclusion criteria. The total number of papers analyzed included publications that utilized the same device, therefore we classified the remaining 32 studies into groups based on the type of robotic walker used. This paper reviewed 15 different types of robotic walkers. CONCLUSIONS: The ability of many-legged robots to negotiate and transition between a range of unstructured substrates suggests several avenues of future consideration whose pursuit could benefit robotic AT, particularly regarding the present limitations of wheeled paediatric robotic walkers for children's daily outside use.IMPLICATIONS FOR REHABILITATIONChildren with lower limb disabilities can benefit from assistive technology designed for daily usage in outdoor surroundings.An extension of existing robotic assistive technology that allows the user to travel safely on irregular surfaces both indoors and outdoors is needed.Approaches used to solve research problems in the field of robotics (outside of the rehabilitation area) can be used to address problems that robotic assistive technology currently faces.There is a need for more research on the development of robotic assistive technology for children with mobility impairments without cognitive delays.

Mobility devices for children with physical disabilities: use, satisfaction and impact on participation.

INTRODUCTION: Children with physical disabilities commonly use mobility devices. There is a lack of studies on the use and impact of mobility devices on activities and participation. Research is needed on satisfaction with the service delivery process of mobility devices. PURPOSE: To examine the use and impact of mobility devices among children with physical disabilities and the satisfaction with the properties of their mobility devices and related services. MATERIALS AND METHODS: A web-based survey was sent to parents of 6 - 18 years old children with physical disabilities who used mobility devices in Iceland. The use and effectiveness of mobility devices were assessed with a questionnaire designed for this study. The satisfaction was measured with Quebec user evaluation of satisfaction with assistive technology (QUEST) 2.0. RESULTS: The survey was sent to 55 families and 36 replied. Most of the children used mobility devices in social activities. The number of participants who reported positive effects of devices on activities and participation, depended on environmental settings. There was no significant difference in participants' satisfaction between types of mobility devices. Also, there was no significant difference in participants' satisfaction with the properties of the device and the related service (for wheeled walkers p = 0.47, manual wheelchairs p = 0.08, powered wheelchairs p = 1.00). CONCLUSIONS: The results indicate the importance of mobility devices for activities and participation and can guide healthcare workers when providing mobility devices where environmental factors across settings must be kept in mind. Stakeholders should be aware of the value of satisfaction with the devices and related services.Implications for Rehabilitation:Children with physical disabilities use mobility devices across different environmental settings and need to have more than one type of equipment.This study confirms results from earlier research that mobility devices are important for the activities and participation of children with disabilities.It is important to understand how the delivery process of devices is perceived by those who receive them. High satisfaction is an indicator of high quality of service.Environmental factors across settings must be kept in mind in the delivery process of assistive devices.

[Initial results of the evaluation of a digital rollator]. / Erste Ergebnisse der Evaluation eines digitalen Rollators.

BACKGROUND: Rollators are preferred to compensate physiological limitations and to maintain mobility in old age; however, environmental obstacles or limited perception of fall hazards can lead to fall events. OBJECTIVE: The present study evaluates an electronic box that is used to supplement conventional rollators with various technical assistance systems (e.g. call for help to contact persons, fall detection). The rollator equiped with the electronic box (DigiRoll) was tested for its suitability for everyday use during the pilot phase of the study, with the aim of further development. METHODS: In a qualitative design, the DigiRoll was tested in a pilot phase with 10 participants. Individuals were interviewed in focus groups and individual interviews. In addition, ethnographic observations were made. The data evaluation was carried out using qualitative content analysis. RESULTS: The test persons showed great interest in the development of the assistance systems to increase the feeling of safety. At the same time, the necessity of adapting the DigiRoll to individual needs became clear, depending on the living situation, the type of impairment and personal habits. CONCLUSION: The DigiRoll has the potential to provide sustainable support for people with reduced mobility by increasing the users' sense of safety. Other contextual factors such as access to suitable rollators and safe walkways cannot be influenced by the DigiRoll.

The Conceptual Development of a Multifunctional Stepladder for Older People and Caregivers.

Stepladders are compact, foldable ladders with flat steps and a platform. Despite all the research and design efforts, there are still limitations in terms of the multifunctionality, usability and simplicity of stepladders and related variants. By combining ideas, features and functions from patent literature, existing products and scientific journals, this study aims to conceptualise a multifunctional stepladder for improved usability. Five concepts are created, which are screened and evaluated against a set of criteria to select the best concept for improved usability, divided into three categories: simplicity, effectiveness and efficiency. The result is a versatile invention that functions as a stepladder, walker, wheelchair and Pilates chair, suitable for older people and caregivers in nursing homes. It allows medical records or supplies to be retrieved from high places without the need for inappropriate aids. The invention can replace wheelchairs and walkers and converts into a Pilates chair to provide a mobile exercise option for older people. The concept offers older people flexibility and independence in terms of mobility and healthcare, while saving space in the nursing home. Further design studies, prototyping and testing are needed before this idea can go into production.

A multi-camera and multimodal dataset for posture and gait analysis.

Monitoring gait and posture while using assisting robotic devices is relevant to attain effective assistance and assess the user's progression throughout time. This work presents a multi-camera, multimodal, and detailed dataset involving 14 healthy participants walking with a wheeled robotic walker equipped with a pair of affordable cameras. Depth data were acquired at 30 fps and synchronized with inertial data from Xsens MTw Awinda sensors and kinematic data from the segments of the Xsens biomechanical model, acquired at 60 Hz. Participants walked with the robotic walker at 3 different gait speeds, across 3 different walking scenarios/paths at 3 different locations. In total, this dataset provides approximately 92 minutes of total recording time, which corresponds to nearly 166.000 samples of synchronized data. This dataset may contribute to the scientific research by allowing the development and evaluation of: (i) vision-based pose estimation algorithms, exploring classic or deep learning approaches; (ii) human detection and tracking algorithms; (iii) movement forecasting; and (iv) biomechanical analysis of gait/posture when using a rehabilitation device.

Gait parameters when walking with or without rollator on different surface characteristics: a pilot study among healthy individuals.

OBJECTIVES: Gait parameters can measure risks of falling and mortality and identify early stages of frailty. The use of walking aid changes gait parameters. The aim of this study was to describe differences in gait parameters among healthy adults when walking on different surfaces and under different conditions, with and without a rollator. RESULTS: Ten healthy participants walked first without and then with a rollator upslope, downslope and on flat surface, on bitumen and gravel respectively. Step length, walking speed and sideway deviation was measured using an inertial measurement unit. Walking up a slope using a rollator generated the longest step length and walking down a slope using a rollator the shortest. Fastest walking speed was used when walking up a slope with rollator and slowest when walking down a slope with rollator. Sideway deviation was highest when walking down a slope and lowest when walking on gravel, both without rollator. Highest walk ratio was found when walk up a slope without rollator and lowest when walking down a slope with rollator. Data from this study provides valuable knowledge regarding gait parameters among healthy individuals, useful for future clinical research relevant for rehabilitation and public health.

The Effects on Gait of 4-Wheeled Walker Use in People with Alzheimer's Disease Dementia and Gait Impairment: A Pilot Study.

In people with dementia, provision of mobility aids is standard treatment for those with impaired gait. However, mobility aid use is independently associated with increased falls risk. In this short communication, gait velocity and stride time variability were recorded in eleven adults with Alzheimer's disease dementia. Three conditions were tested: single-task (no aid), walking with a walker, and dual-task (walker use and counting backwards) under both a straight path and Figure-of-8 walking configuration. Gait velocity increased when using a walker compared to no aid in the Figure-of-8 walking configuration. Walker use improved gait in simple walking, but benefits diminished upon dual-task.

Dynamic 3D DNA Rolling Walkers via Directional Movement on a Lipid Bilayer Supported by Au@Fe3O4 Nanoparticles for Sensitive Detection of MiRNA-16.

Currently reported polyfluorene-based fluorescence detection usually shows high background signal and low detection sensitivity. This work developed a novel three-dimensional (3D) DNA rolling walker via directional movement on a lipid bilayer (LB) supported by Au@Fe3O4 nanoparticles (NPs) in a polyfluorene-based fluorescence system so that it could achieve significantly improved detection sensitivity and almost zero-background signal detection for miRNA-16. First, the carboxyl-functionalized poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadazole)] polymer nanoparticles (c-PFBT PNPs) covalently bonded with amino-labeled single-strand CP and further hybridized with single-strand AP to prepare AP-CP-coupled c-PFBT PNP probes. Meanwhile, Au@Fe3O4 NPs were developed as efficient fluorescence quenchers and served as the matrix for assembling the LB. The resulting Au@Fe3O4@LB assembled cholesterol-labeled orbital DNA L1 and L2 and further assembled hairpins H1 and AP-CP-coupled c-PFBT PNP probes to construct DNA nanomachines. Then, the target miRNA-16 was introduced to initiate the rolling circle amplification (RCA) reaction and form dynamic DNA rolling walkers, thus releasing single-strand CP-coupled c-PFBT PNP probes. The magnetic separation effect of Au@Fe3O4 NPs made it possible to detect the fluorescence signal from the released probes, thus achieving almost zero-background signal detection for miRNA-16 with a low detection limit of 95 aM. The flexible interfaces provided by the LB endowed the DNA rolling walkers with high binding efficiency and low derailment probability, thus achieving significantly improved detection sensitivity. The developed strategy provided an attractive polyfluorene-based fluorescence platform with high-sensitivity and low-background signals.

An instrumented walker in three-dimensional gait analysis: Improving musculoskeletal estimates in the lower limb mobility impaired.

BACKGROUND: In three-dimensional (3D) gait analysis of individuals requiring a walking frame (walker), acquisition of artefact-free motion and force data is challenging. Without inclusion of handle-reaction forces alongside ground reaction forces, external forces used in musculoskeletal modelling are incomplete. This may increase dynamic inconsistencies between the model and measured motions and forces, thus, uncertainties in estimates of musculoskeletal load. RESEARCH QUESTION: To develop an instrumented walker and evaluate the effects of including handle-reaction forces on residual forces during musculoskeletal modelling. METHODS: An instrumented walker measuring handle-reaction forces synchronously with motion capture and ground reaction force data was developed. 3D gait analysis was conducted in ten elderly participants recovering from a proximal femur fracture and requiring a walker for ambulation. Joint kinetics and residual forces were calculated between two external load conditions: (1) external loads applied using only force platforms; or (2) external loads applied using force platforms and walker handle-reaction forces. RESULTS: Including handle-reaction forces reduced residual forces and improved estimates of musculoskeletal loads of the torso (P = <0.001). SIGNIFICANCE: A wide instrumented walker measuring handle-reaction forces allows for the gait analysis of individuals requiring a walker and improves reliability of musculoskeletal dynamics.

The effect of horizontal forces from a Smart Walker on gait and perceived exertion.

Increasingly, electric motors are being incorporated into wheeled walkers to implement various smart features to better assist their users physically. These modified walkers, known as Smart Walkers, use their electric motors to generate horizontal forces that can be used to reduce the physical load for walking, prevent falls and provide navigation support. However, these forces can also alter gait and may inadvertently increase the exertion of the users. This study aims to describe the effects of assistive and resistive horizontal forces (from -18.47 N to 27.70 N) from a Smart Walker on gait and perceived exertion of its users during steady-state walking. Self-selected comfortable walking speed, cadence, stride length, double support phase and ratings of perceived exertion (RPE) were significantly affected and different effects were found for resistive force, relatively low assistive force and high assistive force. With increasing force from -18.47 N to 0 N, RPE decreased and the users walked with lower double support time. From 0 N to 9.23 N, RPE continued to decrease to its lowest point while gait parameters remained constant. Further increasing force up to 27.70 N increased RPE and led to the users to choose to walk at higher speeds. This study demonstrates that users adapt their gait significantly to the forces applied and relatively high constant forces, whether assistive or resistive, will increase perceived exertion. Hence, these need to be carefully considered when developing Smart Walkers in order to provide safe and effective support to its users.

The effect of first-time 4-wheeled walker use on the gait of younger and older adults.

INTRODUCTION: The 4-wheeled walker is intended to enhance balance and gait for older adults. Yet, some research suggests that walking aids increase falls risk. An understanding of the influence of age with walker use on gait performance is required. OBJECTIVE: To examine the effect of initial 4-wheeled walker use on spatiotemporal gait parameters between younger and older adults. DESIGN: Cross-sectional, repeated-measures. SETTING: Community-dwelling. PARTICIPANTS: Twenty-five younger (age: 26.5 ± 4.1 years) and 24 older (age: 68.5 ± 10.5 years) adults participated. Younger adults were aged 18 to 35 years, whereas older adults were 50 years or older. Included were people not requiring the use of a walking aid, and those able to converse in English. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): Gait velocity and stride time variability were recorded using accelerometers. Gait was examined under three conditions: unassisted walking; walking with a 4-wheeled walker; and walking with a 4-wheeled walker while completing a secondary task. Conditions were performed across two walking paths: straight and figure-of-8 Walk Test. Separate mixed-methods analyses of variance (ANOVAs; within-subject: condition/path; between-subject: group) were used for statistical analyses. RESULTS: Velocity was lower when walking using a walker while completing a cognitive task (p < .001), in the figure-of-8 Walk Test (p < .001), and in older adults (p = .001). Stride time variability increased with walking path and condition difficulty (p < .001) for the straight path versus the figure-of-8 Walk Test. CONCLUSIONS: Using a 4-wheeled walker resulted in a slower and more inconsistent gait pattern across both age groups. Walking more complex configurations resulted in the prioritization of gait over the cognitive task while performing the dual-task conditions. No evidence of an age-related difference in the effect of initial walker use on gait was observed. Nonetheless, walkers are cognitively demanding and their introduction should warrant a clinical follow-up.

Effects of assistive devices on postural control following a balance disturbance along the anterior-posterior direction.

BACKGROUND: Assistive devices provide balance and stability to those who require a greater base of support, especially during ambulation or in tasks essential to functional daily living. In ambulatory assistive device use, center of pressure (COP) movement as one of the measurements of postural control is a factor when assessing fall risk, with an overall goal of maintaining postural equilibrium. There is a lack of research on assistive devices, such as walkers, regarding measurable outcome variables related to fall risk. The purpose of this study was to determine how much the postural control in single limb stance during a balance perturbance is affected by utilizing three different walker types designed to promote stability: the standard walker, the front-wheeled walker with straight wheels and the front-wheeled walker with caster wheels. RESEARCH QUESTION: Is postural sway control in single limb stance during a balance perturbance affected by walker type? METHODS: Twenty-three healthy adults participated and gave consent. The NeuroCom® SMART EquiTest® system was utilized to simulate forward falls. Subjects stood on the system's force plate, which was tipped backwards quickly, forcing subjects to attempt to maintain balance. Each participant experienced 18 simulated perturbations, during which they were asked to maintain balance while using one of three walkers in single-limb stance. Each trial was completed using random assignment of three different walker types. Leg dominance of the stance leg was also randomized for each trial. RESULTS: The type of walker and the leg dominance in the standing limb significantly affected postural control in a balance perturbance in the A-P direction. The walker type significantly affected the COP maximum displacement in anterior-posterior (AP) direction. However, the leg dominance significantly affected COP maximum displacement in AP and medio-lateral (ML) directions and COP velocity in AP direction. SIGNIFICANCE: The findings suggest that when fully grounded, a standard walker is more stable than the front-wheeled walker. However, this does not indicate that the standard walker is more stable than other types of walkers when it is being picked up and moved forward during normal use.

Housing design that improves the independence and safety for older adults using a walker.

Globally, the walker is one of the most common assistive technologies used by older adults with mobility impairments, which is also the case in New Zealand. However, there is a scarcity of knowledge regarding their specific requirements in housing design. Adopting an ethnographic approach, the perceptions and spatial use of 16 older adults who used a walker were investigated as part of a larger study on quality of life and housing design. Five emergent themes for walker user perception and spatial use were identified, from which design considerations were distilled and then categorised into 10 design elements. The study highlights differences between the requirements for accommodating walkers and those for accommodating wheelchair users. It provides new insights into improved housing design for older adults, which have the potential to be incorporated into existing frameworks for accessible design and universal design thereby improving the independence and safety of older adults.