With flat feet, the arch is either not fully developed or is completely absent, while with fallen arches, previously developed arches collapse. Secondly, flat feet is congenital or diagnosed during early childhood, while fallen arches occur later in life.

Thus, the two major differences between flat feet and fallen arches are:

• The point of occurrence

• The prior existence or absence of the arch.

Flat Feet

Flat feet is a foot condition where the arches are either not fully developed or completely absent. Medically known as pes planus, this condition is often identified from birth or during early childhood.

There are certain characteristics that define flat feet. They include the following:

• The arch was never formed or was not fully formed, making it congenital or hereditary

• The arch remains flat whether or not it is load-bearing

• It is often asymptomatic, only showing symptoms in some cases

• Can affect both feet or a single foot

Causes of Flat Feet

The primary cause of flat feet is often hereditary. Factors like the shape of the foot bones, and loose ligaments, both of which are mainly passed down from parents to their offspring, are examples of such causes.

Fallen Arches

These are also called adult-acquired flatfoot because they describe a condition where previously fully developed arches collapse. This occurs mainly later in life.

The main characteristics of fallen arches include the following:

• A normal, fully developed arch that collapses

• May affect both feet, but mostly begins with one foot

• Often comes with symptoms like swelling, pain, or discomfort

• Arch will often appear normal when not bearing weight, but collapses once it is weight-bearing

• Mainly occurs with age, usually after the age of 40

Causes of Fallen Arches

Fallen arches are usually the result of injury or a weakening of the structures that support the arch. Some examples of these causes include:

• Injuries – Injuries like sprains, fractures, or other types of impact trauma to the ankle or foot

• PTTD (Posterior Tibial Tendon Dysfunction) – Injury or inflammation of the tendon that provides support to the arch

• Arthritis – Misalignment in the mechanics of the foot arising from inflammation of the joints

• Pregnancy – Weight gain and hormonal changes that affect the integrity of the ligaments

• Aging – Natural wear and tear of the ligaments and tendons over time

• Obesity – Increased strain on the arch because of the excessive weight it is carrying

Summarizing the Differences between Flat Feet and Fallen Arches

From the above, we can now see that all cases of fallen arches lead to flat foot, but not all cases of flat foot are caused by a fallen arch. With these differences, you can now make a clear distinction between the two terms.