Pedographic assessment of the impact of off-the-shelf orthopedic shoes on the load distribution under the feet in patients with a high risk of developing diabetic foot syndrome

BACKGROUND: It is known that the so-called “rocker” outsole helps to reduce the load on the forefoot and toes. Such an outsole is available in ready-made orthopedic shoes of some Russian manufacturers, however, an objective assessment of their impact on the load distribution under the foot during walking has not been carried out.

AIMS: To study the pressure distribution inside the off-the-shelf orthopedic shoes“Sursil-Ortho” in comparison with the load inside the shoes used by patients on a daily basis.

METHODS: We studied 20 patients (40 feet) with a high risk of diabetic foot syndrome. According to clinical data, a risk regions were determined on the plantar surface of the feet. In-shoe pedography (pedar, novel,Germany) was performed in shoes usually worn by the patients, and in orthopedic shoes“Sursil-Orto”(Moscow). The maximum peak pressure (MPP) was calculated. Criterion of efficiency: MPP in the risk region<200 kPa or reducing it by 25% or more.

RESULTS: There was a significant decrease of the median MPP in the forefoot and in the risk region. The percentage of feet with MPP >200 kPa in the risk region decreased from 58% to 30% (p=0,014), in any area of the forefoot — from 63% to 30% (p=0,04). The increase in MPP under the midfoot and hindfoot did not exceed +14% (ns). Tested footwear was effective in 71% of cases. Predictors of the insufficient effect were: higher initial MPP in the risk region, risk region on the hallux or in the lateral part of the forefoot.

CONCLUSIONS: Shoes with a rigid rocker outsole significantly reduce the pressure under the forefoot and under the toes during walking. The degree of load reduction varies: the lateral part of the forefoot and 2-5 toes are most unloaded, and the hallux and medial forefoot are slightly less.

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