Effects of novel diabetic therapeutic footwear on preventing ulcer recurrence in patients with a history of diabetic foot ulceration: study protocol for an open-label, randomized, controlled trial.

Background: Recurrence after the healing of a foot ulcer is very common among patients with diabetes mellitus. Novel diabetic therapeutic footwear consisted of merino wool, vibration chip, and orthopedic insoles is designed to influence multifaceted mechanisms of foot ulcer occurrence. The aim of this study is to examine the effect of the optimally designed therapeutic footwear on preventing ulcer recurrence in patients with a history of diabetic foot ulcers (DFU).

Methods/design: The trial is designed as a two arms, parallel-group, open-label randomized controlled intervention study. The Log-rank Test was used for calculating sample size based on the latest national multicenter survey data of DFU in China. Three hundred and twenty participants will be recruited from the Diabetic Foot Care Center, West China Hospital, Sichuan University. Adults with diabetic peripheral neuropathy, healed foot ulceration in the 3 months prior to randomization, and aged ≥18 years, will be recruited. Participants will be randomized to receive novel diabetic therapeutic footwear (n = 160) or their own footwear (n = 160). The primary outcome will be the incidence of ulcer recurrence. The secondary outcome will be measurements of barefoot dynamic plantar pressures, the influence of footwear adherence on ulcer recurrence, and the incidence of cardiovascular events. Assessment visits and data collection will be obtained at baseline, 1, 3, 6, 9, and 12 months. The intention-to-treat principle will be applied. A cox regression model will be used to calculate the hazard ratio for the incidence of ulcer recurrence. The change of barefoot dynamic plantar pressures will be assessed using repeated measures ANOVA. The study protocol has been approved by the Ethics Committee of The Biomedical Research Ethics Committee of West China Hospital, Sichuan University (Reference No. 2019(96)).

Discussion: This clinical trial will give information on the ability of novel diabetic footwear on preventing ulcer recurrence in patients with a history of diabetic foot ulceration. If the optimally designed therapeutic footwear does work well, the findings will contribute to the development of innovative treatment devices for preventing foot ulcer recurrence in high-risk patients.

Trial Registration: Chinese Clinical Trial Registry ChiCTR1900025538 . Registered on 31 August 2019.