By Jordana Bieze Foster
A scientific approach to insole design can help reduce plantar pressures associated with diabetic footwear, in turn reducing the risk of plantar ulcerations, according to research presented in May at the 2017 ISPO World Congress in Cape Town, South Africa.
In 24 patients with diabetes at high risk for ulceration, investigators from Vrije University Amsterdam in the Netherlands compared fully custom footwear with three noncustom extra-depth footwear conditions that differed with regard to insole design: insoles evaluated and modified based on in-shoe plantar pressure; insoles designed based on barefoot pressure and foot shape, and modified based on in-shoe pressure; and insoles designed and manufactured using computer-assisted techniques based on barefoot pressure and foot shape.
Not surprisingly, pressures under the metatarsal heads were lowest for the custom footwear. But those pressures were lower than 200 kPa (an oft-used threshold for ulceration) in more than 90% of cases with insoles based fully on in-shoe plantar pressure, and in more than 75% of cases with insoles designed based on barefoot pressure and foot shape data and modified based on in-shoe pressure.
“Compared with the more traditional approach to diabetic footwear, we’re moving toward a more scientific approach,” said Sicco Bus, PhD, senior investigator and head of the university’s Human Performance Laboratory, who presented the findings in Cape Town.
Bus S. Precision orthotics to improve the effectiveness of orthopedic assistive devices: therapeutic footwear. Presented at the International Society of Prosthetics & Orthotics World Congress, Cape Town, South Africa, May 2017.