Flat Feet
They are not all the same
“Flat feet” is a common term people use when the arch of the foot appears lower than usual. But did you know that not all flat feet are the same? The underlying causes, or etiologies, can differ greatly, and understanding these differences is key to finding the right treatment.
Flexible vs. Rigid Flat Feet
One of the main distinctions podiatrists look at is whether the flat foot is flexible or rigid.
Flexible flat feet are the most common type. In this case, the arch is visible when the person is sitting or standing on tiptoes, but it flattens out when standing normally. This form is often inherited, linked to ligament laxity, and is usually painless — although in some cases, it may cause fatigue or discomfort with activity.
Rigid flat feet, on the other hand, are less common and more concerning. Here, the arch is absent whether the foot is weight-bearing or not. This can be caused by structural issues such as abnormal bone connections (tarsal coalition), arthritis, or neurological conditions. Rigid flat feet are more likely to cause pain and limit mobility.
Acquired vs. Congenital Flat Feet
Another important difference is whether the condition is present from birth or develops later in life:
Congenital flat feet are usually flexible and due to inherited traits. Many children are born with flat feet, and in most cases, the arch develops naturally as they grow.
Acquired flat feet develop in adulthood, often as a result of injury or degeneration. A common cause is posterior tibial tendon dysfunction (PTTD), where the tendon that supports the arch weakens over time. This type often leads to pain, swelling, and progressive deformity if untreated.
Other Contributing Factors
Flat feet can also be linked to other conditions, including obesity, pregnancy, diabetes, or inflammatory diseases such as rheumatoid arthritis. In these cases, the extra stress on the foot structures contributes to arch collapse.
Why It Matters
Understanding the cause of flat feet is important because not every case requires treatment, but some definitely do. While flexible flat feet may only need supportive footwear, rigid or acquired flat feet may require custom orthotics, physiotherapy, or even surgical intervention.
If you’re unsure what type of flat feet you have, or if you’re experiencing pain, it’s always best to book a consultation. The right diagnosis will guide the right treatment — and help keep you moving comfortably.
