Path Active; Safety and Tolerability Study (PASTS)

Path Active™ comprises a pair of monitoring insoles which measure parameters associated with foot ulceration in diabetes: temperature and pressure. The insoles are linked via an app to the wearer's mobile phone and also to a clinical dashboard so that both wearer and clinician are alerted to early signs of skin damage on the foot so that immediate preventive action can be taken. The study will assess safety and tolerability of Path Active™ in 10 users, who have been assessed as having a 'high risk' of foot ulceration, over a period of 7 days.

Foot complications in people with diabetes are the most common cause of non-traumatic leg amputation in the UK with over 176 leg, toe or foot amputations every week in England. One in seven people with diabetes will develop a foot ulcer at some stage in their lives. Not only does this impair their daily activities and reduce their quality of life, it also increases their risk of amputation by up to 24-fold. Five year mortality for minor and major amputations in diabetes have been reported as 46.2% and 56.6%, respectively. Circulatory problems, nerve impairment and infection contribute to foot complications in diabetes. Prior to a foot ulceration, changes in temperature and/or pressure occur. These early warning signs can be measured by Path Active™ and alert the wearer via a mobile phone app and the clinician via a clinical dashboard so that preventive action can be taken. Currently people with diabetes who have been assessed as 'high risk' for foot ulceration are allocated appointments with podiatrists in 'foot protection teams' who review on a weekly to monthly basis. Path Active™ has the potential to reduce appointments by alerting podiatry teams to potential problems as they occur rather than regular routine reviews. Path Active™ may be able to reduce hospital and clinic visits and thereby reduce healthcare carbon footprint. The primary objective of this clinical investigation is to evaluate the safety and tolerability of Path Active™ in people with diabetes who are at 'high risk' of foot ulceration.

Participant use of Path Active insoles, mobile phone app and clinician's dashboard (where pressure and temperature changes can be reviewed by a clinician). Participants will complete a patient questionnaire relating to use of the device and EuroQol - EQ5D at the beginning and end of the study.

The primary objective of this clinical investigation is to evaluate any adverse events whilst using Path Active™ in people with diabetes who are at 'high risk' of foot ulceration.

EuroQol EQ-5D-5L assessment for quality of life assessment at the beginning and end of the study period. The EQ-5D-5L health profile includes the items mobility (MO), self-care (SC), usual activities (UA), pain/discomfort (PD) and anxiety/depression (AD). The EQ-5D-5L asks respondents to endorse one of five response levels for each item: "no problems," "slight problems," "moderate problems," "severe problems," and "extreme problems"/ "unable to", describing 3125 (55) health state profiles. The instrument also includes a visual analog scale (VAS) anchored by 0 (worst imaginable health) and 100 (best imaginable health) that will be analysed separately from the health profile.

Participants will complete study questionnaires relating to the product (ease of use, use of the mobile phone app, use of the insoles, action taken relating to app warnings)

Reduction in CO2 comparing carbon dioxide emitted due to ulcer treatment vs carbon dioxide emitted due to device manufacture

To model the carbon dioxide reduction that occurs if ulceration and the need for ulcer treatment is prevented. The carbon footprint for the manufacture and life span of the device will been calculated and the carbon footprint for ulcer treatment will be calculated. The difference between CO2 due to manufacture of the device will be compared with the CO2 required for ulcer treatment to show how much reduction in carbon can be made by preventing foot ulceration when using Path Active.

Inclusion Criteria: Participant able to give informed consent. Age >18 at the time of consent. Diagnosis of Type 1 or Type 2 Diabetes. Both Feet Intact (no ulceration). Participant understands and is willing to participate and can comply with the follow-up regime. Participant diabetes foot Risk Stratification as 'High Risk'. Ability to walk independently for > 100 metres i.e without use of wheelchair, walking stick or personal assistance. Participant able and willing to wear suitable footwear. Most own a mobile phone and be willing to upload WWP app. Exclusion Criteria: Either foot has less than 2 arterial vessel run-off on Doppler. Poor visual acuity ie registered blind, unless supported by carer. Current participation in another clinical investigation of a medical device or a drug; or participation in such a study within 30 days prior to study enrolment. Body Mass Index (BMI) >40. Participant has bespoke contact insoles and footwear.

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Chatwin KE, Abbott CA, Boulton AJM, Bowling FL, Reeves ND. The role of foot pressure measurement in the prediction and prevention of diabetic foot ulceration-A comprehensive review. Diabetes Metab Res Rev. 2020 May;36(4):e3258. doi: 10.1002/dmrr.3258. Epub 2019 Dec 11.

Kerr M, Barron E, Chadwick P, Evans T, Kong WM, Rayman G, Sutton-Smith M, Todd G, Young B, Jeffcoate WJ. The cost of diabetic foot ulcers and amputations to the National Health Service in England. Diabet Med. 2019 Aug;36(8):995-1002. doi: 10.1111/dme.13973. Epub 2019 Jun 5.