Optimization of rocker sole footwear
When the ANOVA analysis was repeated on the
Discussion
healthy participants, almost identical statistical trends
were observed. Specially, there were main effects of This study sought to understand the relationship
apex position and rocker angle for every region with between peak plantar pressure and two rocker sole
only the 2-4th MTH region showing an interaction design features in people with diabetes. The purpose
(Fig. 2g-i). The distribution of best apex positions also
followed a similar pattern to that of the group with
diabetes (Table 2), illustrating the group-optimized
design could also be identified from data on healthy
individuals. Nevertheless, pressures were higher in the
was to use this understanding to propose a group
optimized shoe that could be used to reduce pressures
below 200 kPa and potentially avoid the need for
personalized footwear. The data identified that a stiff
soled rocker shoe incorporating an apex position at
52% of shoe length was optimal for pressure reduction
group diabetes by 25% in the 1st MTP region (p < in three high-risk regions of the forefoot. Furthermore,
0.01) and 21% in the 2-4th MTH region (p < 0.01). by combing this with a 20° rocker angle, peak
Table 1: ANOVA statistics, in each anatomical region, for the main effects of apex position, rocker angle and
also for the interaction.
1st MTP 2–4 MTH Hallux
Apex Position F = 18.2, p < 0.001* F = 157.1, p < 0.001* F = 35.7, p < 0.001*
52°-57° (−7.3, 3.5), p = 1.0 (−15.6, −9.1), p < 0.001* (−6.4, 3.2), P = 1.0
52°-62° (−12.2, 1.9), p = 0.32 (−32.9, −20.7), p < 0.001* (−12.8, −1.3), p = 0.008*
52°-67° (−23.4, −8.5), p < 0.001* (−39.0, −28.5), p < 0.001* (−28.4, −13.9), p < 0.001*
57°-62° (−9.4, 2.9), p = 0.97 (−18.9, −9.7), p < 0.001* (−11.6, 0.6), p = 0.10
57°-67° (−20.7, −7.3), p < 0.001* (−25.5, −17.2), p < 0.001* (−26.4, −12.7), p < 0.001*
62°-67° (−15.7, −5.9), p < 0.001* (−10.5, −3.4), p < 0.001* (−19.8, −8.3), p < 0.001*
Rocker Angle F = 67.4, p < 0.001* F = 179.5, p < 0.001* 10 F = 76.2, p < 0.001*
15°-20° (9.8, 16.0) (10.9, 14.7) (11.1, 17.6)
Interaction F = 1.5, p = 0.22 F = 19.1, p < 0.001* F = 1.0, p = 0.41
Both the F-statistic and associated p-value have been reported. In addition, the 95% confidence intervals, and associated
p-values, for the pairwise comparisons between different apex positions are included. Note that these p-values have been
adjusted using a Bonferroni correction for multiple comparisons. All statistical differences (p < 0.01) have been marked with an *.
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