Pes Planus

By Josh Martin, ATC

Pes Planus

Pes Planus or as “Flat Feet” and can occur in individuals of all ages. This condition is a deficiency that transpires to the medial longitudinal arch resulting in loss of function. The medial longitudinal arch connects the forefoot to the hindfoot by a strong bundle of fascia, ligaments, and tendons. Its purpose is to act as a support base for the entire body.

JOI Foot & Ankle Doctors

image of pes planus also known as flat feet

Pes Planus is a condition that may need orthopedic treatment.

Pes Planus dysfunction can cause patients to be symptomatic or asymptomatic. In most cases, this condition will present asymptomatic over the arch but will refer pain to other locations within the body. This is due to improper biomechanics.


Congenital Pes Planus:

Congenital pes planus occurs in infants and developing children resulting from excessive ligamentous laxity and neuromuscular imbalances within the body. In these cases, the ligaments and muscles are extremely flexible to support the medial longitudinal arch during weight-bearing activities. In most cases, children with congenital pes planus will develop a normal arch by age 6.

Acquired Types of Pes Planus:

In most cases, acquired this condition occurs from posterior tibial tendon dysfunction (PTTD). The posterior tibial tendon (PTT) functions to stabilize the medial longitudinal arch under tension, preventing the arch from collapsing. When the integrity of the PTT is impaired, the ligaments surrounding the area become weak, which will result in this condition and other biomechanical problems.

Injuries that occur to the spring ligament can also lead to acquired pes planus. The spring ligament is a strong ligament that connects the navicular to the calcaneus. The ligament’s primary function is to stabilize the calcaneus, navicular, and talus, constructing the medial longitudinal arch. The spring ligament subsequently provides support for the medial longitudinal arch. If the ligament is structurally impaired, it could compromise the integrity of the navicular. This would cause the navicular to drop during weight-bearing activities, which would result in pes planus deformity.

Excessive weight-barring activities can lead to fractures and tissue damage within the medial longitudinal arch. Obesity and excessive weight-barring activities cause micro-trauma within the structural axotomy of the foot. Damage to any of the underlying structures will produce changes within the bones, ligaments, and muscles. This could jeopardize the medial longitudinal arch resulting in pes planus deformity.

Symptoms of Pes Planus

Symptoms typically include pain and tenderness within the medial longitudinal arch of the foot. Typically, the pain is a result of damage to either muscles or ligaments within the foot. This condition can also refer to pain in other locations within the body due to improper biomechanics.

What are the best inserts for pes planus or flat feet

Image of JOI Custom Orthotic Inserts

Treatment: Conservative & Non-Conservative


This treatment option is typically foot orthotics, physical therapy, and NSAIDs. This treatment option focuses on using the dynamic stabilizers within the foot to strengthen and support the medial longitudinal arch.  Patients with this condition could benefit greatly from shoes with arch support or orthotics.  For physical therapy or orthotics appointments, please call 904-858-7045. 


In most cases, surgical intervention for this condition is unnecessary. Imaging such as X-rays and MRIs are used to assesses the structural anatomy of the foot. If structural damage has occurred, surgical repairs can be performed to reconstruct the medial longitudinal arch.

By: Josh Martin, Certified Athletic Trainer

If you would like to make an appointment with an Orthopedic Foot Specialist, please call 904-JOI-2000 or follow the link below.

Book An Appointment with a JOI Physician in Jax.

Book An Appointment with a JOI Physician in Jax.

Skip to content