4 Stages of Posterior Tibial Tendon Dysfunction and Their Diagnoses

Posterior Tibial Tendon Dysfunction (PTTD) is a common cause of flat foot deformity in adults. It occurs due to damage to the posterior tibial tendon. The posterior tibial tendon connects the calf muscles to bones on the inside of your foot and is responsible for supporting the arches. When it is affected, the arch collapses, causing pain in the ankle and foot.

Along with the pain, PTTD is also associated with foot and ankle swelling, warmth, redness and pain that worsens during activity, an inward rolling of the ankle, and turning out of the toes and foot. PTTD is progressive in nature, meaning that the symptoms get worse as the condition progresses.

There are four distinct stages with varying levels of symptoms.

Stage 1

Stage 1 is often missed because it comes with little or no symptoms, even though the tibial tendon is injured. A radiological examination will also show nothing. However, it is sensitive to the single-toe raise test.

To perform the test. You’ll begin in a standing position and lift the unaffected foot off the ground. Afterward, attempt to lift onto the toes of the affected foot, which you will be unable to do if you suffer from PTTD. There can also be associated tenosynovitis (inflammation of the tissue surrounding a tendon).

Stage 2

At Stage 2 PTTD, there is a torn tendon that affects regular functioning. Stage 2 can be further divided into Stage 2A and 2B.

In stage 2A, there is a flat foot deformity, a flexible hindfoot but an otherwise normal forefoot. A radiological investigation will reveal an arch collapse deformity. Also during physical examination, the single-leg heel raise test will be negative but there will be mild sinus tarsi (center ankle) pain.

In stage 2B, there is an associated abduction of the forefoot but otherwise remains the same as stage 2A.

Stage 3

This stage is characterized by significant deformation of the entire foot as well as degenerative changes to the connective tissue in the hindfoot. Physical examination at this stage will reveal severe sinus tarsi pain while a radiological exam will reveal subtalar arthritis and arch collapse deformity.

Stage 4

By stage 4, the deltoid ligament is compromised and there are degenerative changes at the ankle joint. Consequently, the flatfoot deformity is worse, usually a rigid forefoot abduction and a rigid hindfoot valgus. A physical examination will reveal ankle pain and severe sinus tarsi pain. As for radiography, it will show an arch collapse deformity, subtalar arthritis, and talar tilt on the mortise view.

When Is Surgery Necessary for PTTD?

In treating flatfoot deformity, conservative means are usually the first line of intervention. Rest, use of custom orthotics, immobilization, ice, medication, and exercises can all help to relieve pain, strengthen tendons, and aid healing. However, if the pain persists even after six months of treatment or there is no improvement, surgery may be necessary.

The surgical approach will depend on the severity of the condition and the level of deformity in the foot. Debridement, reconstruction, and fusion are three common approaches to the surgical management of PTTD when it is deemed necessary.