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Shape memory alloys (SMAs) have an innate property that allows them to return to a memorized form when stimulated. They have been recently designed as flexible fabrics for use in wearable assistive devices. This study aimed to develop a rehabilitation assistive glove with good wearability for a hemiplegic patient using a knitted SMA with a high-unidirectional contractile response. We fabricated warp-knitted SMA actuators, which had higher contractile responses than those of weft-knitted SMA. The use of a knitting loom allowed these actuators to fit all the fingers of a patient. We developed a full-fabric glove, placed the SMA wires on the finger regions to form a tendon-driven structure, and attached knitted SMA actuators to the dorsal and palmar sides of the hand to assist flexion and extension. The joint range of motion after glove actuation increased by 11.620% and 141.710% in flexion and extension, respectively. The range of motion improved more with glove rehabilitation than with thermal stimulation or no actuation. The grip force also increased by 52.400% after rehabilitation exercises. The safety of the heat generated during actuation was confirmed, and its applicability as a thermal stimulus was validated (based on increased skin temperature). These outcomes suggest the practical potential of warp-knitted SMAs in fully fabricated wearable assistive devices. [ABSTRACT FROM AUTHOR]

We developed the knitted shape-memory alloy (SMA) as a flexible actuator and applied it to a soft wearable exoglove for rehabilitation assistance. Based on user needs and anthropometric data, we custom-designed the exoglove for three hemiplegic patients using the knitted-SMA actuator and evaluated its bending performance, gripping force and wearability under the four simulation conditions (S1–S4). To address the specific needs, both SMA plain- and double-knit modules were applied to the exoglove based on the patients' finger joint range of motion (ROMs). The joint ROMs of all fingers increased by 13.71% and the skin temperature increased by 2.21 °C after actuating the glove (p = 0.006). The gripping force increased as much as 55.01%, when compared to the baseline. All patients were able to don and doff the developed glove independently, and positively evaluated their subjective satisfaction and thermal perception. The findings suggested the potential of the knitted SMA for the future development of soft wearable robots. [ABSTRACT FROM AUTHOR]

Out-toeing gait may cause alterations in lower limb biomechanics that could lead to an increased risk of overuse injuries. Surgery and physical therapy are conventional methods for mitigating such gait, but they are costly and time-consuming. Wearable devices like braces and orthoses are used as affordable alternatives, but they apply non-negligible stress on the skin. Haptic feedback-delivering shoes were also recently developed, but they require actuators and power sources. The purpose of our study is to develop compression tights with inward directing taping lines that apply compression to lower limb muscles and segments to facilitate inward rotation of the foot, overcoming the drawbacks of previous methods. These compression tights were manufactured to fit the average height, leg length, hip girth, and waist girth of South Korean females in their twenties. The efficacy of these compression tights was evaluated by comparing walking kinematics and user satisfaction of 12 female dancers with an out-toeing gait under three conditions: wearing tights with taping lines, tights without taping lines, and basic bicycle shorts. The foot rotation angles and joint kinematics were recorded using a pressure-pad treadmill and motion capture system, respectively. Multiple pairwise comparisons revealed that the compression tights with inward-directing lines significantly reduced foot rotation angles (up to an average of 20.1%) compared with the bicycle shorts (p = 0.002 and 0.001 for dominant and non-dominant foot, respectively) or the compression tights without taping lines (p = 0.005 and p = 0.001 for dominant and non-dominant foot, respectively). Statistical parametric mapping revealed significant main effects of the tight type on joint kinematics. Also, t-tests revealed that the participants reported significantly higher ratings of perceived functionality and usability on the compression tights with inward-directing taping lines. In conclusion, we developed a comfortable and practical apparel-type wearable and demonstrated its short-term efficacy in mitigating out-toeing gait. [ABSTRACT FROM AUTHOR]

High-collar shoes are a biomimetic approach to preventing lateral ankle injuries during high-demand activities; however, the influence of collar stiffness (CS) on parameters related to lateral ankle sprain prevention during running remains unclear. In this study, we investigated the effects of a custom-designed shoe CS on muscular activity, dynamic stability, and leg stiffness (Kleg) during running using a biomimetic design approach inspired by the mechanisms of ankle sprain prevention. Sixteen healthy male participants ran on a treadmill while wearing a custom-designed high-collar shoe with low, medium, and high CS conditions, measured using circumferential ankle pressure (CAP). Lower extremity kinematics and electromyography (EMG) data were recorded simultaneously. One-way repeated-measures ANOVA was conducted to compare the CS conditions. Results indicate that high and medium CS conditions significantly reduce sagittal and frontal ankle ranges of motion (ROMs) compared to the low CS condition, providing improved stability and support against lateral ankle sprain; moreover, there was a trend towards higher dynamic stability and Kleg with increasing CS. Our study highlights the importance of considering the CAP in regulating high-collar stiffness properties and how higher CS may provide better support for the ankle during running. Nevertheless, additional research is necessary to validate the efficacy of the current design in preventing ankle sprains during high-demand activities. [ABSTRACT FROM AUTHOR]

Electronic monitoring systems have been globally adopted to track criminals to ensure public safety efficiently. In this study, we aimed to assess the wearability of an electronic bracelet using multiple evaluation methods, including the evaluation of range of motion (ROM), air gap (AG), and clothing pressure (CP) at the wearer's wrist, as well as self-scoring of subjective comfort (SC). We recruited eight Korean male participants (N = 8) who were in their 30 s and did not have any musculoskeletal problems at data collection. We compared the test results collected on the first day with those obtained after wearing the electronic wrist bracelet for 5 consecutive days. We also examined the differences between the normal-weight and overweight groups. Overall, the data evinced a decrease in the wrist ROM, AG, and SC, but an increase in the CP after it was worn for 5 days. And, the results were more observable in the overweight group, as compared to the normal-weight group. Furthermore, this study proposed a novel and effective assessment tool that could be used to measure the wearability of devices or systems intended to be worn on the human body—not only the electronic wrist bracelet for criminal monitoring but also popular commercial electronic bracelets for sportswear or health-related monitoring system. [ABSTRACT FROM AUTHOR]

Osteoarthritis is a chronic disease that affects joint cartilage and can cause severe pain and disability. Minor neglected injuries may also result in other diseases that affect daily life. Various attempts have been made to develop wearable auxiliary devices using functional fabrics, but few have simultaneously provided both heat and pressure. Using knitted shape memory alloy (SMA) fabric, a module was manufactured that achieved bending and contraction during operation. An elbow brace that simultaneously provided heat and pressure was developed using this module. Subjective evaluation and measurements of the range of motion (ROM), changes in skin temperature (T sk ), clothing pressure (P c ), and blood flow (F b ) were conducted on the elbow brace while being worn by 10 participants. The multifunctional elbow brace (MFEB) developed in this study generated pressure and heat that increased T sk and P c , ultimately increasing F b . In addition, the ROM of the elbow joint was increased after actuating the elbow brace. Subjective evaluation of the heat and pressure sensation demonstrated its applicability to the human body. We confirmed that the elbow brace had a positive effect on F b and increased the ROM of the joint. These results show the applicability of smart textiles to the development of various wearable devices. [ABSTRACT FROM AUTHOR]