PTTD Complications: What Happens If You Don’t Treat It

If you’re dealing with posterior tibial tendon dysfunction (PTTD), you might be wondering whether treatment is really necessary. Maybe the pain isn’t that bad yet, or you think you can manage it on your own. Here’s the honest truth: PTTD is a progressive condition. Without proper treatment, complications don’t just possible—they’re likely.

The good news? Understanding what can happen if PTTD is left untreated also shows you exactly why early intervention matters so much.

Why Complications Develop

PTTD doesn’t just affect your tendon—it sets off a chain reaction throughout your foot. The posterior tibial tendon is like the main support cable for your arch. When it weakens or gets damaged, your arch starts to collapse. That collapse shifts stress to other structures in your foot that weren’t designed to handle it.

Think of it like a bridge losing its main support cable. The other cables have to pick up the slack, but they’re not built for that extra load. Eventually, they strain too—and that’s when things start to go wrong.

This is why PTTD is now called progressive collapsing foot deformity (PCFD). The word “progressive” is doing a lot of work here.

Common PTTD Complications

1. Progressive Flatfoot (Acquired Adult Flatfoot)

This is the most direct outcome of untreated PTTD. As the tendon weakens, your arch collapses further. What starts as mild flattening can become a severe, obvious flatfoot deformity over time.

The earlier stages might just mean your shoes wear out faster on the inside. Later stages can mean visible changes to how you walk and stand. Many people don’t realize how much their arch has dropped until they look back at old photos or compare their foot to what it used to look like.

2. Arthritis in the Foot and Ankle

When your foot structure changes, the way forces travel through your joints changes too. This leads to abnormal wear on the cartilage in your hindfoot and midfoot joints. Studies show that advanced PTTD frequently coexists with arthritis in these areas.

Once arthritis sets in, it’s not reversible. The damage is done. Managing arthritis becomes part of your treatment plan for life.

3. Tendon Rupture

In severe cases—usually after years of untreated PTTD—the tendon can actually tear or rupture completely. This is often sudden and painful. When the posterior tibial tendon ruptures, the arch collapse becomes dramatic and immediate.

Surgical repair for a ruptured tendon is more complex than treating PTTD in earlier stages. Recovery takes longer, and outcomes aren’t as predictable.

4. Chronic Pain

What starts as occasional pain with activity can become a constant companion. As the deformity progresses, pain may shift to different areas of your foot—not just along the tendon, but on the outside of your ankle where increased strain shows up.

This chronic pain can affect your sleep, your work, and your ability to do the things you enjoy.

5. Activity Limitation

Many people with advanced PTTD find they can’t do the activities they once loved. Running, hiking, even walking for extended periods becomes difficult or impossible. The further the condition progresses, the more your activity options shrink.

6. Foot Deformity Changes

Beyond the flattened arch, untreated PTTD can lead to other alignment issues. Your heel may rotate outward (valgus alignment), and your midfoot can shift outward as well (abduction). These changes affect how you walk and can lead to additional problems like bunions or hammertoes.

When Do Complications Typically Appear?

This varies significantly from person to person. Some people progress from early-stage PTTD to severe deformity within a few years. Others may have mild PTTD for decades without major complications.

Factors that speed up progression include:

  • Being overweight — extra weight stresses the tendon more
  • High-impact activities — running, sports with jumping
  • Diabetes — affects tendon health and healing
  • Continuing the same activities that caused the problem in the first place

The Bottom Line: Early Treatment Prevents Complications

Here’s what you need to take away: the complications of PTTD are largely preventable—if you address the condition early.

Early-stage PTTD often responds well to conservative treatments:

  • Custom orthotics to support your arch
  • Physical therapy to strengthen supporting muscles
  • Activity modification to reduce strain
  • Proper footwear with motion control
  • Weight management if needed

These interventions don’t just manage symptoms—they can slow or stop the progression of the deformity. That’s the key point: you’re not just treating pain today, you’re protecting your foot for years down the road.

When to See a Doctor

If you have any symptoms of PTTD—pain along the inside of your foot or ankle, swelling, flattening of your arch, or difficulty with activities—get evaluated. Early diagnosis gives you the best chance of avoiding complications.

Don’t wait until the pain becomes severe or your foot obviously changes shape. The earlier you address PTTD, the better your long-term outcome.

Sources

  • American Academy of Orthopaedic Surgeons (AAOS) - Posterior Tibial Tendon Dysfunction