Diabetic Foot Ulcers (DFUs) pose a serious health risk to people with diabetes, with a high risk of recurrence following the first DFU and a risk of foot amputation or death. It greatly impacts patient quality of life and costs the NHS up to 1% of its annual budget. Over the last 20 years, work has highlighted the link between DFU formation and normal forces. More recently, work has highlighted the importance of strain/shear forces, which are inherently coupled with normal forces. While limited lab-based in-shoe systems have been produced to detect shear, they alter the shoe-foot interface and are not commercially available. Additionally, consultation with people with diabetes highlighted that they may not wear shoes around the house, leaving long periods where in-shoe solutions cannot track forces. We, therefore, present the development of a novel plantar shear measuring system, the Shear Tracking for Enhanced Prevention Sock (STEPS), an instrumented garment to provide an accessible tool for people at risk with DFU. Integrating sensors within the sock provides a solution that seamlessly integrates within the foot-shoe environment, is suitable for shoeless use, and helps mitigate adherence issues. A prototype STEPS was produced, successfully integrating printed resistive strain sensors (proxy for shear) within custom-designed socks using conductive embroidery for flexible connectivity. The strain sensor has a low profile (<0.5 mm thickness) and remains unobtrusive. Preliminary testing shows the capacity for strain measurement of 12+%, with a resolution of 0.013 Ω across a 20 Ω range, demonstrating good sensitivity over 90 cycles. Proof-of-concept testing characterised the system’s ability to measure plantar strain. A single-participant pilot study demonstrated that STEPS captures repeatable, gait-synchronised strain signals during walking, with a signal-to-noise ratio exceeding 30 dB and between-repeat correlations of up to R=0.77, supporting its potential to detect strain (as proxy for shear) during daily activity.

Continuous glucose meters (CGMs) are increasingly used for diabetes management but raise environmental concerns due to short product lifetimes and materials-intensive designs. This study evaluates the potential of applying circular economy (CE) strategies to reduce the environmental impacts of CGMs. Our approach uses an integrated environmental assessment which combines life cycle assessment (LCA) with product-scale material composition analysis (MCA), informed by material flow analysis (MFA) principles. Three commercially available CGMs were assessed and compared with a conventional finger-prick glucose meter as a baseline. Two CE scenarios were modelled: (i) a modular design, in which the applicator and transmitter were redesigned as reusable components with extended lifetimes while allowing single-use needle replacement, and (ii) material substitution, where polycarbonate components and packaging were replaced with lower-impact alternatives. Across all case studies, the CE scenarios reduced combined product and packaging material use by 54-84% and climate change impacts by up to 66.5% relative to the extant (non-circular) baseline. The modular design scenario delivered the greatest environmental benefit by extending the functional lifespan of key components. Packaging and electronic components were thus identified as dominant environmental hotspots, indicating priorities for future redesign. Overall, the results demonstrate that CE-oriented redesign can substantially improve the environmental sustainability of CGMs without compromising functionality and highlight the value of integrating material composition mapping with LCA to support sustainability-driven medical device design.

BACKGROUND:Diabetes-related foot ulceration (DFU) represents a significant and increasing cause of morbidity and economic burden to health services. Surgical offloading has shown great effectiveness in the prevention and healing of DFU. The objective of this review is to assess the effectiveness of submetatarsal plantar fat pad modulation in preventing DFU and to characterise the different biomaterials used to this end. METHODS:The study was registered on PROSPERO. A search strategy of the PubMed, CINAHL and Cochrane biomedical databases was conducted. Any study which explored the modulation of the plantar submetatarsal fat pad for the prevention or treatment of DFU in adults was included. The main outcome was the occurrence of ulceration following intervention. RESULTS:Of the 3162 retrieved studies, 10 studies met inclusion criteria, describing outcomes for 76 participants with 112 ulcers or pre-ulcerative areas. Four studies report results of injectable liquid silicone in 55 participants, four studies included the use of an acellular allograft in eight participants, two studies included autolipotransplantation in 11 participants and one study reports on the use of injectable collagen in two participants. Only one randomised control trial was identified while the remainder of the studies were observational, case-series, or case-reports. The overall ulcer occurrence was 27/112 over an average follow-up of 32.4 months. DISCUSSION:While plantar fat pad modulation shows promise as a surgical offloading strategy for DFU, insufficient high-quality trial data preclude meaningful interpretation of its merits. This is further complicated by heterogeneity in the biomaterial employed for modulation.

The Circular Economy (CE) is fundamental to reducing healthcare’s environmental impact. Moving toward a CE requires closing, narrowing and slowing the flow of materials, parts and products involved in the healthcare system. Materials are critical to medical device circularity. Currently, manufacturers’ material selection processes focus on cost, logistics, manufacturing and regulation. However they neglect the latter phases of the product life-cycle, impeding the move towards circular materials and products.We propose a tool for ‘circular material selection’ in medical devices, using the Multi-Criteria Decision Method (MCDM) to evaluate potential materials. While widely used in other sectors, MCDM is limited in medical devices. The Circular Materials MCDM for Medical Devices (CM3D) addresses this gap and considers the entire product life cycle. Stakeholders informed selection of circular evaluation criteria, with the VIKOR algorithm used to rank material alternatives to identify an ideal ‘circular’ candidate.A case study demonstrates CM3D’s practical application in laparoscopic scissor blades and handles. CM3D provides objective assessment of candidate materials and identifies a tungsten carbide coating for scissor blades and stainless steel for handles, aligning with research literature. Future work will apply CM3D to other medical devices and consider wider implementation within multi-component design cycles.

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 Ω across a range of 0–430 Ω and a range of interest of 0–20 Ω. 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.

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: Investigating in AI’s utility in diverse learning environments can provide insights into its broader applicability in healthcare innovation. Objectives: This study aims to assess the impact on idea generation and implications of incorporating generative AI technology into the framework of a global surgery hackathon, focusing on its use with surgical care providers in Sub-Saharan Africa. Method: A 120-minute interdisciplinary hackathon in Kenya was organised. The event featured the use of ChatGPT, a large language AI model from OpenAI, to facilitate and guide team discussions and solution development. Data was collected through direct observations and discussions among participants. Results and Conclusions: The hackathon saw active participation from ninety attendees, who were divided into ten teams of 8-12 members each. These groups utilised AI to seek information, derive inspiration, and refine their ideas. Notable challenges identified included issues related to AI-generated biases and the accuracy of information provided. The study serves as a proof-of-concept that generative AI can effectively be integrated into hackathons to foster innovation, with the caveat that future implementations should focus on developing unbiased and accurate AI models. This approach has significant potential to improve educational strategies and operational efficiency in the healthcare and technology sectors.

BackgroundDiabetic 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. ObjectiveThis 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. MethodsThis 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. ResultsThree 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. ConclusionsWhile 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.

Background Continuous positive airway pressure (CPAP) is a well-established treatment modality for children in moderate and severe respiratory failure in well-resourced settings. However, the availability of CPAP is generally poor in many resource-limited settings, in large part because existing CPAP devices are not designed for cost and resource efficiency, which precludes their use. The LeVe CPAP System has been co-developed by an international multidisciplinary team specifically for use in low-resource settings. In this paper we report the first study evaluating the efficacy of using the LeVe CPAP System as an intervention for children with acute hypoxaemic respiratory failure at Mengo Hospital in Kampala, Uganda. Methods A total of 42 paediatric patients were recruited onto the study, all of whom were failing to maintain oxygen saturation above 88% at room conditions. Key clinical measures, including oxygen saturation, heart rate, respiratory rate and dyspnoea were recorded every hour for the length of admission on the paediatric ward. Results At completion, 39 patients had recovered and were successfully discharged while 3 of 42 (7%) died in the early phases of treatment. Surviving patients showed improvements in all clinical measures, particularly in the first 12 h of treatment, and no adverse effects were reported after continued use. Additionally, we interviewed five parents whose children were undergoing treatment to gain a qualitative assessment of perceptions to the LeVe CPAP System. Conclusion Outcomes of the study demonstrate the capability of the LeVe CPAP System to treat paediatric patients in respiratory failure and support the system's wider adoption in low-resource settings.

Osteoarthritis (OA) is a widespread, debilitating joint disease associated with articular cartilage degradation. It is driven via mechano-inflammatory pathways, whereby catabolic genes in the cartilage-embedded chondrocytes are presumed up-regulated due to increased shear stress arising from friction at the cartilage surface as joints articulate. The enhanced expression of these cartilage-degrading and inflammatory genes leads to tissue degeneration. However, the nature of the stress, and how the cells within the joint respond to it, are poorly understood. Here we show, in a proof of concept study on a mouse model where surgical joint destabilisation has been carried out to induce OA, that the early up-regulation of the matrix metalloproteinase 3 (Mmp3) gene, a member of the matrix-degrading MMP family, and of the interleukin-1 beta (Il1b) gene, a key mediator of inflammatory response, are significantly suppressed when lipid-based lubricants are injected into the joints. We attribute this to the reduction in frictional stress on the chondrocytes due to the lubricant at the cartilage surface. At the same time, Timp1, a compression but not shear-stress sensitive gene, is unaffected by lubricant. Our results demonstrate that cartilage lubrication modulates catabolic gene regulation in OA, shed strong light on the nature of the chondrocytes' response to shear stress, and have clear implications for novel OA treatments. STATEMENT OF SIGNIFICANCE: Osteoarthritis (OA) is a widespread, debilitating joint disease associated with degradation of the articular cartilage, the tissue that covers and protects the joint surfaces as they rotate. Such degradation is due to catabolic enzymes expressed by cartilage-embedded chondrocytes (the only cell type in cartilage) in response to mechanical stress. In this proof-of-concept study in a mouse OA model, we show that reduction of cartilage friction by liposome-based lubricants suppresses the production of the catabolic, OA-related genes in chondrocytes. Our findings provide direct evidence in an animal model that catabolic genes are induced in chondrocytes in a mechanosensitive manner, related to the friction at the cartilage surface, and identify putative novel OA treatments through efficient cartilage lubrication.

The formation of diabetic foot ulcers (DFU) is consequential of peripheral neuropathy, peripheral arterial disease and foot deformity, leading to altered foot biomechanics and plantar loads. Plantar load comprises of normal pressure and shear stress, however, there are currently no in-shoe devices capable of measuring both components. The STrain Analysis and Mapping of the Plantar Surface (STAMPS) system, developed at the University of Leeds, utilises Digital Image Correlation (DIC) to measure the strain captured by a plastically deformable insole, as a method to understand plantar load during gait. A 2D DIC software was used to capture cumulative plantar strain and displacement pointwise data, however this method was limited to the analysis of planar surfaces. To address this, 3D instrumentation and DIC methods have been developed and implemented into the STAMPS3D system, used as a tool to capture data that is representative of the non-planar nature of plantar surfaces of the foot. A case-study is used to demonstrate how STAMPS3D can measure multi-dimensional strain, bringing potential to improve clinical screening of DFU risk.

Diabetic foot ulceration is linked to high amputation and mortality rates, with the substantial associated annual spend on the at-risk diabetic foot reflecting the intensive time and labour involved in treatment. Assessing plantar interactions and developing improved understanding of the formation pathways of diabetic ulceration is important to orthotic interventions and patient outcomes. Plantar skin surrogates which emulate the mechanical and tribological characteristics can help improve physical models of ulceration, reduce reliance on cadaveric use and inform more complex computational modelling approaches. The information available from existing studies to characterise plantar skin is limited, typically featuring ex-vivo representations of skin and subcutaneous tissue combined and given focus to shear studies with time dependency. The aim of this study is to improve understanding of plantar tissue mechanics by assessing the mechanical characteristics of plantar skin in two groups; (1) non-diabetic and (2) diabetic donors without the subcutaneous tissue attachment of previous work in this field. Digital image correlation was used to assess inherent skin pre-tension of the plantar rearfoot prior to dissection. Young’s modulus, storage and loss moduli were tested for using tensile stress–strain failure analysis and tensile and compressive dynamic mechanical analysis, which was conducted on excised plantar rearfoot donor specimens for both disease state cohorts at frequencies reflecting those achieved in activities of daily living. Plantar skin thickness for donor specimens were comparable to values obtained using ultrasound acquired in vivo values. Median tensile storage and loss moduli, along with Young’s modulus, was higher in the diabetic cohort. With a mean Young’s modulus of 0.83 ± 0.49 MPa and 1.33 ± 0.43 MPa for non-diabetic and diabetic specimens respectively. Compressive studies showed consistency between cohorts for median storage and loss moduli. The outcomes from this study show mechanical characteristics of plantar skin without the involvement of subcuteanous tissues under reflective daily achieved loading regimes, showing differences in the non-diabetic and diabetic specimens trialled to support improved understanding of plantar tissue response under tribological interactions.

Objective The Global IDEAL Sub-Framework Study aimed to combine the intended effects of the 2009/2019 IDEAL (Idea, Development, Exploration, Assessment, Long-term study) Framework recommendations on evaluating surgical innovation with the vision outlined by the 2015 Lancet Commission on Global Surgery to provide recommendations for evaluating surgical innovation in low-resource environments.Design A mixture of methods including an online global survey and semistructured interviews (SSIs). Quantitative data were summarized with descriptive statistics and qualitative data were analyzed using the Framework Method.Participants Surgeons and surgical researchers from any country.Main outcome measures Findings were used to suggest the nature of adaptations to the IDEAL Framework to address the particular problems of evaluation in low-resource settings.Results The online survey yielded 66 responses representing experience from 40 countries, and nine individual SSIs were conducted. Most respondents (n=49; 74.2%) had experience evaluating surgical technologies across a range of life cycle stages. Innovation was most frequently adopted based on colleague recommendation or clinical evaluation in other countries. Four themes emerged, centered around: frugal innovation in technological development; evaluating the same technology/innovation in different contexts; additional methodologies important in evaluation of surgical innovation in low/middle-income countries; and support for low-income country researchers along the evaluation pathway.Conclusions The Global IDEAL Sub-Framework provides suggestions for modified IDEAL recommendations aimed at dealing with the special problems found in this setting. These will require validation in a stakeholder consensus forum, and qualitative assessment in pilot studies. From assisting researchers with identification of the correct evaluation stage, to providing context-specific recommendations relevant to the whole evaluation pathway, this process will aim to develop a comprehensive and applicable set of guidance that will benefit surgical innovation and patients globally.

IntroductionIlizarov fixators are reliant on tensioned fine wires for stability. The tension in the wires is generated using specific tensioning devices. Loss of wire tension over time may lead of loss a stability and complications. A series of in vitro experiments were undertaken to explore wire tensioner accuracy, the impact of fixation bolt torque and initial tension on loss of tension in ilizarov constructs under static and dynamic loads.Materials & MethodsMedical grade materials were applied to a synthetic bone analogue using surgical instruments in all experiments. Bolt torque was fixed at 6, 10 or 14 Nm using a torque limiting wrench. Wire tension was assessed using a strain measurement bridge. Wires were tensioned to 90, 110 and 130kg as measured by a commercial dynamometric tensioner. Static and dynamic testing was undertaken using an instron testing machine. Cyclical loads from 50–750N were applied for 5000 cycles.ResultsActual wire tension was approximately 15% less than indicated by the tensioner device. Using fixation bolt torques of 10Nm and 14Nm achieved final wire tensions of around 60% and 80% of that applied at 90 and 130kg of applied tension. Static load testing demonstrated self stiffening to similar levels in all pre-tensions. Dynamic testing demonstrated significant loss of tension, most of which occured in the first 3 cycles, inversely proportional to the tension initially applied.ConclusionsThese experiments provides insight into the effect of initially applied wire tension on Illizarov mechanical performance. It is important surgeons understand how the different ways that these devices are applied affects mechanical performance. Further research examining what factors affect performance across different manufacturers equipment would therefore be relevant, alongside the development of novel fixation methods to reduce wire slippage and the further development of equipment for clinical use.

BACKGROUND:No in-shoe systems, measuring both components of plantar load (plantar pressure and shear stress) are available for use in patients with diabetes. The STAMPS (STrain Analysis and Mapping of the Plantar Surface) system utilises digital image correlation (DIC) to determine the strain sustained by a deformable insole, providing a more complete understanding of plantar shear load at the foot-surface interface. RESEARCH QUESTIONS:What is the normal range and pattern of strain at the foot-surface interface within a healthy population as measured by the STAMPS system? Is STAMPS a valid tool to measure the effects of plantar load? METHODS:A cross-sectional study of healthy participants was undertaken. Healthy adults without foot pathology or diabetes were included. Participants walked 20 steps with the STAMPS insole in a standardised shoe. Participants also walked 10 m with the Novel Pedar® plantar pressure measurement insole within the standardised shoe. Both measurements were repeated three times. Outcomes of interest were global and regional values for peak resultant strain (SMAG) and peak plantar pressure (PPP). RESULTS:In 18 participants, median peak SMAG and PPP were 35.01 % and 410.6kPa respectively. The regions of the hallux and heel sustained the highest SMAG (29.31 % (IQR 24.56-31.39) and 20.50 % (IQR 15.59-24.12) respectively) and PPP (344.8kPa (IQR 268.3 - 452.5) and 279.3kPa (IQR 231.3-302.1) respectively). SMAG was moderately correlated with PPP (r= 0.65, p < 0.001). Peak SMAG was located at the hallux in 55.6 % of participants, at the 1st metatarsal head (MTH) in 16.7 %, the heel in 16.7 %, toes 3-5 in 11.1 % and the MTH2 in 5.6 %. SIGNIFICANCE:The results demonstrate the STAMPS system is a valid tool to measure plantar strain. Further studies are required to investigate the effects of elevated strain and the relationship with diabetic foot ulcer formation.