Optimization of rocker sole footwear
pressures were reduced below the 200 kPa threshold
in a large proportion (71–81%) of individuals with
diabetes. Importantly, the optimal apex of 52% was
the same for all three high-risk plantar regions. This
design configuration could therefore be appropriate for
prefabricated footwear and provided without the need
for plantar pressure measurement and personalization
of footwear design.
Based on requests in the literature [1] we focused on
a cohort with diabetes but no history of ulceration.
This relatively lower risk group are unlikely to
choose footwear which they deem to have an
unacceptable appearance, such as the extra depth
footwear sometimes advocated post first ulceration
[23]
. Therefore, we sought to understand the effect
of decreasing rocker angle from 20° to 15°, as using
this lower angle will produce footwear with a thinner
outsole that may be perceived as more acceptable and
may enhance adherence. The decrease in rocker angle
from 20° to 15° led to an decrease in the number of
participants beneath the critical threshold of 200 kPa
(Table 3). However, decreases were modest (6–12%)
Table 2: Distribution of best apex position (corresponding to minimum peak pressure) across the cohort for
the two rocker angles in each of the three anatomical regions.
Participants with Diabetes
1st MTP
2-4 MTH
Hallux
Healthy Individuals
Apex position Rocker angle =15° Rocker angle = 20° Rocker angle =15° Rocker angle = 20°
52% 42% 46% 39% 56%
57% 30% 26% 39% 32%
62% 20% 23% 14% 9%
67% 8% 5% 8% 3%
52% 75% 87% 68% 88%
57% 19% 13% 23% 8%
62% 2% 0% 6% 5%
67% 5% 0% 3% 0%
52% 25% 45% 33% 35%
57% 38% 25% 32% 41%
62% 30% 21% 27% 15%
67% 75% 9% 8% 9%
Percentage values are provided for each apex position, with the group-optimised design (highest percentage) shown in bold.
These data have been provided separately for the participants with diabetes and also the health individuals.
Current Pedorthics | July/August 2019
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