Mueller-Weiss syndrome is a rare condition that causes severe arch pain on the inside of your mid- and hindfoot. It’s mostly found in people ages 40-60, and it’s much more common in women. It’s a progressive disease, meaning it gets worse over time, and it usually affects both of your feet. It causes flatfoot, which happens when your arch collapses. It can also cause your feet to be disfigured or bent out of shape.
What Causes Mueller-Weiss Syndrome?
Experts don’t know its exact cause. But they think it may be caused by things like:
- A forceful squeeze or compression on the cluster of bones in your midfoot (known as the lesser tarsus)
- A birth defect (congenital)
- The loss of blood supply to your navicular bone (ischemia)
Your navicular bone is a half-moon or boat-shaped bone in the middle of your foot. If it suddenly loses its blood supply, your bone tissue starts to die, which then causes your joint to erode and your bone to collapse over time.
Your navicular bone also happens to be the last bone to fully form (known as ossification) in your foot during childhood. If this bone was slow to form, you might be at risk for Mueller-Weiss syndrome. Research also suggests you might be at higher risk if you’re obese or overweight.
What Are the Symptoms of Mueller-Weiss Syndrome?
- Severe midfoot pain
- Foot swelling
- Tenderness on top of your feet
- Arch pain
- Trouble walking
- Your navicular bone becomes comma or hourglass shaped.
But it might take months or years before you notice any symptoms.
How Is It Diagnosed?
Because Mueller-Weiss syndrome is uncommon, it’s often under- or misdiagnosed. That’s because doctors might be slow to identify flatfoot issues. If you have foot pain, especially in your arch or around your midfoot, let your doctor know.
They may run a few imaging tests on both of your feet. Those may include:
This will help them get a clear picture of what’s going on. Based on the amount of tissue death and erosion you may have in your navicular bone and its surrounding area, they’ll stage your condition and symptoms as mild (stage 1), moderate (stage 2-3), or severe (stage 4-5).
What Are the Treatment Options?
For now, there isn’t one best treatment for Mueller-Weiss syndrome. If your condition and symptoms are in the early stages, your doctor may prescribe nonsurgical therapies to help improve your quality of life.
These may include:
- Anti-inflammatory medications (NSAIDs)
- Braces that cover and support your foot and ankle (ankle-foot orthosis)
- A temporary foot cast to stop you from moving your foot too much
- Custom insoles or shoes for pain relief and arch support (orthotics)
- Less physical activity
If these therapies don’t ease your pain, or your symptoms get worse over 6 months, your doctor might consider surgery. It’s often recommended if your condition is past stage 2.
The surgery might include a combination of:
Talonavicular cuneiform arthrodesis. This procedure is done to ease your foot pain and restore some arch support.
Bone grafting. For this procedure, your doctor will take a piece of bone from your hips, legs, or ribs and use it to repair your damaged foot bones. In some cases, they might use bone from a donor.
There are other types of surgeries for this condition, such as joint fusion, but they are less common. You may need physical therapy before and after your surgery to help you recover.
What’s the Outlook?
Over-the-counter pain medications, custom shoes, and foot braces might help ease your pain, take any pressure or stress off your feet, and improve your quality of life. If these therapies don’t help, talk to your doctor to find out if surgery might be an option for you.