What Is PTTD (Posterior Tibial Tendon Dysfunction)?

PTTD, or posterior tibial tendon dysfunction, happens when the tendon that runs along the inside of the ankle and supports the arch becomes strained, inflamed, or weakened. Because this tendon is one of the arch's main structural supports, PTTD often shows up as a gradually collapsing or flattening arch, along with pain and swelling along the inside of the ankle and foot. Fulton insoles are designed to help relieve the strain on this tendon by supporting the arch from underneath, so the tendon isn't doing all the structural work on its own. Because PTTD can progress if left unaddressed, a podiatrist's evaluation is worthwhile alongside any supportive footwear changes.

What Causes a Collapsing Arch?

A collapsing arch usually develops when the posterior tibial tendon weakens faster than the surrounding structures can compensate. Overuse from standing, walking, or running on hard surfaces, along with natural changes that come with aging, are common contributors. Overpronation both worsens and results from a collapsing arch — as the arch flattens, the foot rolls further inward, which places even more strain on the already-weakened tendon. Fulton insoles are designed to help relieve this cycle by supporting the arch directly, reducing how much the tendon has to stretch and strain to hold the foot's structure through each step.

How Insoles Help Support a Collapsing Arch

Insoles help by taking on some of the structural support work the posterior tibial tendon can no longer fully provide on its own. Fulton insoles offer full-length arch support that props up the arch from below, easing the tension the tendon would otherwise be under with every step. A deep heel cup adds rear-foot stability, which helps control the inward rolling motion that accelerates arch collapse and tendon strain.

How Proper Alignment Helps Manage PTTD

Alignment plays a central role in how PTTD progresses. When the foot rolls inward with each step, the already-weakened posterior tibial tendon absorbs more stress than it's able to handle, which can accelerate further arch collapse. Fulton insoles are engineered with a biomechanical footbed that limits excess pronation and keeps the rear foot more centered through the stride, reducing the repetitive strain placed on the tendon.

Why Fulton Works for PTTD & Collapsing Arch Support

Full-length arch support that offloads the posterior tibial tendon. 

Fulton's arch support spans the full medial column of the foot, helping carry the structural load the tendon can no longer fully support on its own.

Deep heel cup for neutral rear-foot alignment. 

Fulton's structured heel cup keeps the heel centered on each footstrike, reducing the inward-rolling motion that places additional strain on an already-weakened tendon.

Cork-rubber footbed that molds to your foot. 

Fulton's natural cork-and-rubber base molds to your unique arch shape after about 10 hours of wear, providing consistent support for a foot whose own structure is doing less of the work.