Study on relationship between foot pressure pattern and Hallux Valgus (HV) progression

Abstract

Hallux valgus is one of the most common foot deformities. Plantar pressure technologies are used widely for determination of biomechanical changes in foot during walking. There are already published claims relating to the pressure distribution of HV condition. However some of these claims are disputed and challenged. Although, disputed or otherwise, association of HV to sole pressure widely presented as a means of identifying such condition. Or knowing that HV exist, establishing what kind of pressure variation is expected may lead to better foot wear design for HV patients. Despite of extensive work on sole pressure patterns of patients, there has been no reported work found on conditions which leads to HV. Considering the fact that 23% of adults develop such condition during their life time, understanding HV is badly needed. To have better understanding of how plantar pressure patterns can be linked to the deformity progression or existence, extracting some patterns out of force and pressure measurements can be beneficial in recognising the patients with and without deformity during their gait cycle. We examined the dynamic changes of the forces that applied to the whole sole of the feet in control group and in the patients group when they walked at different speeds. It was observed for those with HV condition having higher forces on 2nd and 3 rd metatarsal heads, and less force on the 1st metatarsal head compared to those without the condition. Although this finding was previously reported in the literature what was new was the fact that, speed of walking shown to have a significant influences on plantar force distribution. This finding in itself is significant as no sole pressure distribution given in conjunction with walking speed in the past. It was observed that there was significant variability of pressure distribution of the same individual from one trial to another indicating that getting consistent pressure pattern is an important hurdle to overcome. After many trials individuals' walking regulated giving consistent readings. After achieving this, it was further discovered that pressure pattern very much depended on walking speed. Considering the fact that inconsistency of pressure of unregulated (casual) walking and variability of due to speed raises doubts of validity of previously published work on HV which ignored such factors. Having said that, in our studies too, raised loading is observed on Metatarsal 2 and, 3 although it was not possible to give statistical significance to these finding. Although the loading on metatarsal 2 and 3 may indicate existence of HV, in authors' opinion, there is little chance of using pressure pattern as a predictive tool as no such pressure increase observed on those appeared to be at the start of HV condition or any individual with normal feet. © 2013 Springer-Verlag.