Pain Relief, physical therapy

The REAL cause of plantar fasciitis

Plantar fasciitis is by far one of the more debilitating of musculoskeletal conditions around. There is typically no “cause,” clients just start to complain of their arches hurting. Pain is usually worse in the morning, and activities such as standing, prolonged walking and running will also cause symptoms to worsen. So, what is the “real” cause of it. In order to answer it, we need to look at the biomechanics of how forces work in our body.

Let’s look at the foot first. You can see that both the achilles tendon (calf muscles) and the plantar fascia are attached to the same bone. If you naturally have more weight distribution towards your toes, the calves will become overdeveloped, tight, and create tension at the calcaneus (heel bone). This will also create tension at the plantar fascia and over time, will aggravate the nerves underneath, creating inflammation.

So you just need to stretch your calves and your toes and everything will be better right? Well, for a select few, it may be enough to create a physiological change, but for others it doesn’t do much but bring some temporary relief. We have to investigate deeper as to WHY you are putting more weight through your toes when you stand and walk.

Zone of Apposition

This takes me to the big picture. In order to look at overall weight distribution through your feet, we have to look at the biomechanics of the entire body. This is one of my favorite pictures. The skeleton to the left is optimal position, the other two are suboptimal. The red line is the relationship between the diaphragm’s position and the lower extremity chain. Now look at arrows. If the ribcage is elevated, the head, spine, and entire lower extremity chain is pulled forward. This causes your center of gravity to pull forward, and…you guessed it: creates increased weight through the balls of your feet. The unequal weight distribution becomes a compensatory breathing strategy, because the diaphragm is unable to fully activate in this position.

How do you fix it? The key is changing this thing called the Zone of Apposition (ZOA). This area represents the space where the diaphragm is attached to the ribcage and spine and defines the relationship between the two. Look at the left skeleton again- see how the diaphragm is domed? This is an optimal position for proper diaphragm activation, and in return, proper biomechanial posture. The right skeleton has a very flat diaphragm, because the ribcage is elevated, so the diaphragm is being stretched, making it less effective. When the diaphragm is less effective, your body will compensate for this, because breathing is mandatory and will override your desire for pain relief. So you can stretch all day long, but if you require a foot position with weight more on your toes because that’s the only way your body can breathe, then you aren’t going to see the long term changes you desire by working on the foot alone. You must work on the ribcage position to produce an effective diaphragm.

Now that you’ve learned the biomechanics of weight distribution, it should be a little easier for you to understand the deep underlying cause of plantar fasciitis. There are some other factors that I haven’t gotten into such as pelvis position and lack of glute activation, but most of the clients I see with plantar fasciitis have a diaphragm dysfunction. By improving the ribcage position, the body will redistribute weight backwards and relieve tension at the balls of the feet. As long as this position is maintain, symptoms so improve on a more permanent scale.

Are you having foot pain that isn’t going away? I would love to help you! Contact me here for a postural assessment.


Mead, J. (1979). Functional significance of the area of apposition of diaphragm to rib cage [proceedings].. The American review of respiratory disease. 119. 31-2. 10.1164/arrd.1979.119.2P2.31.

Postural Restoration Institute:

1 thought on “The REAL cause of plantar fasciitis”

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s