Foot loading is different in people with and without pincer nails: a case control study

Area of Science:

• Biomechanics
• Dermatology
• Gait Analysis

Background:

• Pincer nails are often linked to reduced upward mechanical forces on the toe pad.
• Clinically significant pincer nails are also observed in healthy individuals, suggesting other factors may be involved.
• A hypothesis proposed that inadequate physical stimulation during walking contributes to pincer nail development in some cases.

Purpose of the Study:

• To investigate the gait characteristics of individuals with pincer nails by measuring plantar pressure during walking.
• To determine if altered plantar pressure distribution is associated with pincer nail development.

Main Methods:

• A prospective case-control study involving 12 bilateral pincer nail cases and 12 healthy controls.
• Plantar pressure during barefoot and shod ambulation was measured using a digital pressure-plate system (S-Plate platform).
• Analysis included first toe pressure and frequencies of peak pressure in different foot areas (first toe, metatarsal head).

Main Results:

• The pincer nail group exhibited significantly lower first toe pressure compared to controls, both barefoot and shod.
• The primary peak pressure area in the pincer nail group was the metatarsal head, while it was the first toe in the control group.
• Peak pressure area was identified as a significant risk factor for pincer nail development.

Conclusions:

• Walking behavior appears to be a contributing factor in the development of pincer nails.
• Correcting walking behavior to increase pressure on the toe pad may offer a treatment approach for pincer nails in walkers.