Pes Planovalgus: More Than “Flat Feet”

When it comes to foot health, “flatfoot” is one of the most commonly used terms. However, pes planovalgus is not just a flattened arch. It is a three-dimensional deformity involving a collapse of the medial arch, outward heel tilt (valgus), and forefoot abduction. It may progress over time and can affect both children and adults.

In many people it is mild and manageable, but in others it can cause pain, fatigue while walking, shoe wear problems, and limitations in daily life.

What Is Pes Planovalgus?

Pes planovalgus describes a combination of:

• Medial arch collapse (loss of the normal inner foot curve)
• Hindfoot valgus (the heel tilts outward)
• Forefoot abduction (the front of the foot turns outward)

Clinically, it is often grouped into two main types:

• Flexible flatfoot: The arch appears when non-weight-bearing or when standing on tiptoes, but collapses with weight-bearing. Common in children and often painless.
• Rigid flatfoot: The arch remains absent regardless of position. It may be associated with structural problems such as tarsal coalition or advanced degeneration, and is more likely to be painful.

Why Does It Happen?

In children, flexible flatfoot is frequently related to ligamentous laxity and genetics. Excess weight can increase symptoms. If the foot is stiff and painful, conditions such as tarsal coalition should be considered.

In adults (acquired flatfoot), the most common cause is posterior tibial tendon (PTT) dysfunction. The PTT is a key dynamic supporter of the arch. Over time, repetitive overload, obesity, trauma, or inflammatory arthritis may weaken or tear the tendon. As the tendon fails, ligament structures become overloaded and the arch progressively collapses.

Symptoms and Diagnosis

Common symptoms include:

• Pain or tenderness along the inside of the foot and ankle
• Fatigue with walking or prolonged standing
• Shoes wearing out more on the inner side
• In later stages, pain on the outer side of the foot (sinus tarsi region)

Two practical clinical signs are:

• “Too Many Toes” sign: From behind, more toes are visible than usual because the forefoot drifts outward.
• Single-leg heel rise test: Difficulty or inability to rise on tiptoes on one foot suggests PTT dysfunction.

Diagnosis typically includes weight-bearing X-rays to assess alignment and severity. MRI may be used to evaluate tendon and ligament integrity when needed.

Treatment Options

Treatment depends on flexibility, pain severity, functional limitations, and associated pathology. Many cases—especially early and flexible deformities—improve without surgery.

Non-surgical treatment may include:

• Custom orthotics to support the arch
• Ankle-foot orthoses (AFO / Arizona brace) in more symptomatic cases
• Stretching (especially if the Achilles tendon is tight)
• Physiotherapy focusing on posterior tibial strengthening and gait mechanics
• Pain and swelling control with activity modification and medication when appropriate

Surgical treatment is considered when pain persists or the deformity progresses. Procedures are selected “à la carte” based on the patient’s needs and may be combined:

• Tendon procedures: PTT debridement/repair and, in selected cases, FDL tendon transfer
• Bone realignment (osteotomies): medializing calcaneal osteotomy, lateral column lengthening (Evans), and selected arch-raising procedures
• Arthroereisis: an implant in the sinus tarsi to limit excessive valgus in selected cases
• Arthrodesis (fusion): when the deformity becomes rigid and arthritis develops

Take-Home Message

Pes planovalgus should not be dismissed as “just flat feet.” Early assessment and the right conservative plan can reduce symptoms and slow progression. In advanced cases, modern reconstructive surgery can successfully restore alignment and improve quality of life.