Introduction
Anatomy
Symptoms
Diagnosis
Treatment
Rehabilitation
Prevention
Introduction
Flat feet is very common, especially among children. As for adults, approximately 15% of the population have low arches or flat feet. Most cases of flat feet are considered “flexible flat feet” and do not need to be treated. When a child with a flexible flat foot is asked to stand tiptoed, the arches will reappear and the heels will turn inwards, suggesting the flexibility of the tarsal bones. Only a small percentage of flat feet are due to lower limb muscle imbalance or tarsal bone coalitions (a congential condition in which some tarsal bones are fused), uncommon pathologies that need to be diagnosed and managed by orthopaedic surgeons.
Anatomy
Babies are born with flat feet. Foot arches develop only when a child starts to walk. When a child reaches the age of 1, the ratio of the width of the instep to that of the heel is 1:1. At the age of 14, the arch of the foot is fully developed and the ratio is around 0.6:1. As a person ages, the arch usually flattens out a bit. The ratio for adults is around 0.75:1.
Flexible flat feet is not considered a pathology but a variant of normal physical characteristics, partially related to the laxity of the musculoskeletal makeup.
Symptoms
Usually flat feet are asymptomatic apart from low foot arches and a comparatively larger surface of sole touching the ground while standing. There may be more wearing of the shoe on the medial side of the heel. Foot pain caused by this condition is not common.
Diagnosis
To determine whether your arch is high or low, an impression of the feet is made on a piece of paper. The higher the ratio of the width in the instep to that of the heel, the lower the arch is. This suggests the presence of flat feet. On the other hand, if the ratio of the width of the instep to that of the heel is relatively narrow, it indicates high arch. According to empirical studies by Staheli et al (1987), the normal range of this ratio goes from 0.3:1 (high arch) to 1.4:1 (flat feet).
Treatment
It is not necessary to correct flat feet if it does not present any pain or discomfort. It is recommended to wear comfortable shoes that support and protect the feet when walking.
Rehabilitation
Frequent stretching exercises for the Archilles tendon and the muscles of the soles will reduce activity-related pain or tiredness in the feet, ankles or legs. If discomfort continues, soft, firm or hard-molded arch supports may be recommended to relieve foot pain and fatigue.
Prevention
The arches of flexible flat feet cannot be expected to be moulded or rebuilt by shoes or orthosis.
Dr. Bobby NG