Effects of rocker-sole footwear on postural stability and plantar load distribution during standing: A Charcot foot...

This study evaluated the influence of rocker-sole inclination angle and apex position on postural stability and load distribution while standing in therapeutic footwear.

A single patient with remission-stage CNO was assessed under three conditions: barefoot (BF), 15° rocker shoes (Shoe15), and 20° rocker shoes (Shoe20). All measurements were performed in standing conditions, including quiet standing on a pressure platform and balance testing on an unstable platform. Postural stability was evaluated using the Biodex Balance System, and standing load distribution and center-of-pressure (CoP) behavior were assessed using a Zebris pressure platform. Statistical analysis was performed using Friedman's ANOVA with post hoc testing (interpreted descriptively due to the single-case design).

The 20° rocker condition was associated with reduced postural stability, as indicated by a higher Fall Risk Test Index and increased CoP path length and velocity. Standing load distribution shifted markedly between limbs, with load transferring from the affected left foot (91% barefoot) to the right foot (∼69-70% in footwear conditions). This change represented a reversal of asymmetry rather than normalization. Within the affected foot, a posterior shift in load distribution (reduced forefoot, increased hindfoot contribution) was observed.

Rocker-sole footwear influenced both postural stability and standing load distribution in this case. More aggressive rocker geometry was associated with greater redistribution of load but reduced stability, indicating a potential trade-off. These findings are limited to standing conditions and cannot be generalized to dynamic gait. Individualized footwear design may be necessary to balance stability and mechanical load redistribution in patients with Charcot Foot.