Analysis of skeletal characteristics of flat feet using three-dimensional foot scanner and digital footprint.

Background: Flat feet increase the risk of knee osteoarthritis and contribute to frailty, which may lead to worse life prognoses. The influence of the foot skeletal structure on flat feet is not yet entirely understood. Footprints are often used to evaluate feet.

Foot-surface-structure analysis using a smartphone-based 3D foot scanner.

Background: A thorough understanding of the influence of the foot skeletal structure on hallux valgus (HV) is required for HV prevention. We developed a system using a 3D foot scanner on a smartphone to clarify the relationships between foot features and HV risk.

Methods: Two-dimensional video images were recorded on a smartphone, sent to a computer or cloud server, and used to construct a 3D foot-feature model, considering 10 foot features associated with HV.

Development of a quantitative measurement system for three-dimensional analysis of foot morphology using a smartphone.

Existing techniques for measuring foot morphology are invasive or cumbersome. A new technique was developed using a smartphone, which can measure foot morphology to within 1 mm. This is shown to be applicable to the prediction of hallux valgus, which allows for early intervention.

Parasympathetic activation enhanced by slow respiration modulates early auditory sensory gating.

Sensory gating is a preattentional mechanism to filter irrelevant information from the environment. It is typically reflected as a suppression of the event-related P50 component for successive sounds in the auditory modality. Although stress-induced sympathetic activation has been reported to disrupt P50 suppression, little is known about the modulatory effect of parasympathetic activation on early auditory sensory gating.