A comparison of group-optimized and individually-
selected footwear designs
Abstract
Background: Appropriate footwear
for individuals with diabetes but no
ulceration history could reduce the risk
of first ulceration. However, individuals
who deem themselves at low risk are
unlikely to seek out bespoke footwear
which is personalized. Therefore,
our primary aim was to investigate
whether group-optimized footwear
designs, which could be prefabricated
and delivered in a retail setting, could
achieve appropriate pressure reduction,
or whether footwear selection must
be on a patient-by-patient basis. A
second aim was to compare responses
to footwear design between healthy
participants and people with diabetes in
order to understand the transferability
of previous footwear research,
performed in healthy populations.
Methods: Plantar pressures were
recorded from 102 individuals with
diabetes, considered at low risk of
ulceration. This cohort included 17
individuals with peripheral neuropathy.
We also collected data from 66 healthy
controls. Each participant walked in 8
rocker shoe designs (4 apex positions
× 2 rocker angles). ANOVA analysis was
then used to understand the effect of
two design features and descriptive
statistics used to identify the group-
optimized design. Using 200 kPa as a
target, this group-optimized design was
then compared to the design identified
as the best for each participant (using
plantar pressure data).
Results: Peak plantar pressure
increased significantly as apex position
was moved distally and rocker angle
reduced (p < 0.001). The group-
optimized design incorporated an apex
at 52% of shoe length, a 20° rocker
angle and an apex angle of 95°. With
this design 71–81% of peak pressures
were below the 200 kPa threshold, both
in the full cohort of individuals with
diabetes and also in the neuropathic
subgroup. Importantly, only small
increases (<5%) in this proportion
were observed when participants
wore footwear which was individually
selected. In terms of optimized
footwear designs, healthy participants
demonstrated the same response as
participants with diabetes, despite
having lower plantar pressures.
Conclusions: This is the first study
demonstrating that a group-optimized,
generic rocker shoe might perform
almost as well as footwear selected on
a patient by patient basis in a low risk
patient group. This work provides a
starting point for clinical evaluation of
generic versus personalized pressure
reducing footwear.
Current Pedorthics | July/August 2019
35