A stakeholder informed, low-cost, personalised 3D-printed insole for diabetic foot ulcer prevention

Background: Diabetic Foot Ulcer (DFU) incidence will rise in line with the increasing global prevalence of diabetes. Healthcare providers must develop effective interventions that address the needs of patients and clinicians if DFUs are to be prevented.

Aim: Engage with stakeholders (patients and clinicians) to inform the development and evaluation criteria of a novel low-cost 3D-printed insole to reduce DFU risk in patients with neuropathy.

Method: Data from the transcripts of 15 semi-structured patient interviews and the views of 7 podiatrists were used to develop a consensus statement of insole design specifications.

A prototype insole was developed and evaluated against these specifications. Clinical effectiveness was established by comparing reduction in peak plantar pressures and patient perceived comfort of 4 people with diabetic neuropathy whist wearing 1) no insole 2) standard custom insole and 3) 3D-printed insole conditions. The F-scan in-shoe pressure measurement system was used to collect kinetic data. Insoles were presented in a random order with participants blinded to the condition.

Results: The 3D-printed insole fulfilled most of the design specifications including being lightweight, easy to clean and walk in. It was more effective at reducing forefoot plantar loads when compared to the standard insole condition, reducing mean peak plantar pressure by 31%, a 4% greater reduction over the standard insole condition.

Conclusion: This study provided valuable pilot data for the efficacy, acceptability and future direction of this intervention. The impact of stakeholder involvement on insole design, adherence and ulceration rate need to be evaluated through a clinical trial.