Background: Diabetic foot ulcers are common and costly. Most cases are preventable, although few interventions exist to reliably support patients in performing self-care. Emerging technologies are showing promise in this domain, although patient and health care provider perspectives are rarely incorporated into digital intervention designs. Objective: This study explored patient and health care provider feedback on a smart sensing sock to detect shear strain and alert the wearer to change their behavior (ie, pause activity and check their feet) and considered how patient experience and attitudes toward self-care are likely to impact uptake and long-term effective engagement with the device to curate guiding principles for successful future intervention development. Methods: This qualitative study combined semistructured interviews and a focus group alongside a participant advisory group that was consulted throughout the study. In total, 20 people with diabetic neuropathy (n=16, 80% with history of diabetic foot ulcers) and 2 carers were recruited directly from podiatry clinics as well as via a recruitment network and national health mobile app for one-to-one interviews either in person or via landline or video call. A total of 6 podiatrists were recruited via professional networks for 1 virtual focus group. Participants were asked about their experience of diabetic foot health and for feedback on the proposed device, including how it might work for them in daily life or clinical practice. The data were analyzed thematically. Results: Three main themes were generated, each raising a barrier to the use of the sock complemented by potential solutions: (1) patient buy-in—challenged by lack of awareness of risk and potentially addressed through using the device to collect and record evidence to enhance clinical messaging; (2) effective engagement—challenged by difficulties accepting and actioning information and requiring simple, specific, and supportive instructions in line with podiatrist advice; and (3) sustained use—challenged by difficulties coping, with the possibility to gain control through an early warning system. Conclusions: While both patients and podiatrists were interested in the concept, it would need to be packaged as part of a wider health intervention to overcome barriers to uptake and longer-term effective engagement. This study recommends specific considerations for the framing of feedback messages and instructions as well as provision of support for health care providers to integrate the use of such smart devices into practice. The guiding principles generated by this study can orient future research and development of smart sensing devices for diabetic foot care to help optimize patient engagement and improve health outcomes.

Diabetic Foot Ulcers (DFUs) are a significant health and economic burden, potentially leading to limb amputation, with a severe impact on a person’s quality of life. During active movements like gait, the monitoring of shear has been suggested as an important factor for effective prevention of DFUs. It is proposed that, in textiles, strain can be measured as a proxy for shear stress at the skin. This paper presents the conceptualisation and development of a novel strain-sensing approach that can be unobtrusively integrated within sock textiles and worn within the shoe. Working with close clinical and patient engagement, a sensor specification was identified, and 12 load-sensing approaches for the prevention of DFU were evaluated. A lead concept using a conductive adhesive was selected for further development. The method was developed using a Lycra sample, before being translated onto a knitted ‘sock’ substrate. The resultant strain sensor can be integrated within mass-produced textiles fabricated using industrial knitting machines. A case-study was used to demonstrate a proof-of-concept version of the strain sensor, which changes resistance with applied mechanical strain. A range of static and dynamic laboratory testing was used to assess the sensor’s performance, which demonstrated a resolution of 0.013 $\mathrm{\Omega }$ across a range of 0–430 $\mathrm{\Omega }$ and a range of interest of 0–20 $\mathrm{\Omega }$. In cyclic testing, the sensor exhibited a cyclic strain threshold of 6% and a sensitivity gradient of 0.3 ± 0.02, with a low dynamic drift of 0.039 to 0.045% of the total range. Overall, this work demonstrates a viable textile-based strain sensor capable of integration within worn knitted structures. It provides a promising first step towards developing a sock-based strain sensor for the prevention of DFU formation.

Monitoring the human-exoskeleton interface (HEI) is vital for user safety in assistive exoskeletons. Considering interaction forces during design can improve comfort and efficiency and reduce resistance and inertia. Challenges include covering the lower limb area without interfering with user-robot interaction. This paper presents a force-sensitive resistor (FSR) based sensing sleeve for use within the HEI. The design includes 30 sensors and works independently of it to assess attachment modalities. System characterisation tests the system with human trials. Demonstrating that a low-cost, flexible sensing array can accurately monitor HEI. This provides a promising tool for assessing human-robot interaction and investigating wearable robotic device use.

Using body-worn sensors in healthcare can bring yield clinically valuable information but risks affecting the interface under investigation. Diabetic foot ulcers (DFUs) are a significant health and economic burden, frequently leading to limb amputation with a severe impact on patient quality of life. Clinicians and patients urgently require information about foot condition to inform DFU prevention strategies, but the addition of sensors at the foot interface risks causing inappropriate loads and adverse clinical outcomes. This work proposes a novel strain-sensing technology that can be integrated unobtrusively within sock textiles at the foot interface. Context-specific set of requirements were established to evaluate potential sensing modalities. A total of 12 load-sensing methods were identified, not limited to DFU sensing to investigate possible solutions. Candidate technologies we evaluated against the specification and selected a silver-based adhesive exhibiting strain-sensitive resistance. Sensor development was undertaken through parametric experimental testing using a stretchable textile substrate. A characterisation process determined the sensor has a resolution of 0.013 $\Omega$ in a range of 0 - 430 $\Omega$ and a range of interest of 0 - 20 $\Omega$. The sensors demonstrated the capacity to cover an appropriate measurement range (0 - 12\% strain). Composite reinforcement increased strain capacity to 20\% during quasi-static testing. After development, the final sensor design performance was asessed, integrating the sensing unit within a knitted structure produced using an industrial sock-knitting machine. The system was evaluated through a cyclic loading regime. A strain threshold of 6\% was determined with a peak sensitivity gradient of 0.3 \textpm 0.02. A dynamic drift of 0.039 to 0.045\% (total range) was identified over usage, with micro-tearing identified as the mechanism of action. In conclusion, this study demonstrates a viable textile-based strain sensor capable of integration within knitted structures. It provides a promising first step towards developing a sock-based strain sensor to aid the prevention of DFU formation.

BACKGROUND Diabetic foot ulcers are common and costly. Most cases are preventable, although few interventions exist to reliably support patients in performing self-care. Emerging technologies are showing promise in this domain, although patient and health care provider perspectives are rarely incorporated into digital intervention designs. OBJECTIVE This study explored patient and health care provider feedback on a smart sensing sock to detect shear strain and alert the wearer to change their behavior (ie, pause activity and check their feet) and considered how patient experience and attitudes toward self-care are likely to impact uptake and long-term effective engagement with the device to curate guiding principles for successful future intervention development. METHODS This qualitative study combined semistructured interviews and a focus group alongside a participant advisory group that was consulted throughout the study. In total, 20 people with diabetic neuropathy (n=16, 80% with history of diabetic foot ulcers) and 2 carers were recruited directly from podiatry clinics as well as via a recruitment network and national health mobile app for one-to-one interviews either in person or via landline or video call. A total of 6 podiatrists were recruited via professional networks for 1 virtual focus group. Participants were asked about their experience of diabetic foot health and for feedback on the proposed device, including how it might work for them in daily life or clinical practice. The data were analyzed thematically. RESULTS Three main themes were generated, each raising a barrier to the use of the sock complemented by potential solutions: (1) patient buy-in—challenged by lack of awareness of risk and potentially addressed through using the device to collect and record evidence to enhance clinical messaging; (2) effective engagement—challenged by difficulties accepting and actioning information and requiring simple, specific, and supportive instructions in line with podiatrist advice; and (3) sustained use—challenged by difficulties coping, with the possibility to gain control through an early warning system. CONCLUSIONS While both patients and podiatrists were interested in the concept, it would need to be packaged as part of a wider health intervention to overcome barriers to uptake and longer-term effective engagement. This study recommends specific considerations for the framing of feedback messages and instructions as well as provision of support for health care providers to integrate the use of such smart devices into practice. The guiding principles generated by this study can orient future research and development of smart sensing devices for diabetic foot care to help optimize patient engagement and improve health outcomes.