This is one of those injuries that seems to be in every runner’s vocabulary. Just about everyone has heard of it, many if not most runners have suffered from it, but few really understand what it is, why it occurs, or how to most effectively treat it. Since it is the most common injury to the foot (and one of the most prevalent running ailments in general), it warrants a close look.
The plantar fascia is a dense connective tissue which runs along the sole of the foot from the heel to just about the base of the toes. It attaches to a small area on the bottom of the calcaneus (heel bone) and then fans out as it runs up to the toes. It is this area of attachment that becomes the site of injury. (To find it, just take your right foot with your hands and turn it so that you can see the sole. Looking at just the bottom of the heel, the plantar fascia would attach at about 1:00, not exactly dead center on the heel as you might expect.) It functions somewhat like a ligament — that is, its purpose is to provide support and stability to the arch of the foot. It is a passive structure, which means we have no voluntary control over its movement like we do with muscles.
The “-itis” (inflammation) invades the plantar fascia when the stresses on the tissue become overwhelming, either through too much force (as in speedwork) or through simple overuse (too many miles). Often, abnormal biomechanics of the foot are implicated along with those two factors. And as you already know if you’ve been following this column, what we’re talking about here is excessive or ill-timed pronation. Most people associate overpronation with “flat-feet,” a not entirely accurate description but a useful one in this case. Since the plantar fascia is designed to support the long arch of the foot during stance, it’s not hard to see that forces causing a flattening of that arch will result in increased tension on this tissue. The fascia gives way at it’s weakest point, which happens to be its attachment on the heel. As the fascia repeatedly pulls away from the bone, the body’s response is to grow new bone to “chase after it.” What you have then is the “bone spur” that is often used as the diagnosis for this injury. This is unfortunate, because the image conjured by this term is of a sharp, pointy dagger jabbing down at the bottom of the foot, causing all this pain. In fact, the bone spur is directed horizontally and causes no pain by itself. It is simply a result of the real problem, the detaching plantar fascia and the inflammation around it.
The typical picture of plantar fasciitis consists of pain at the aforementioned attachment site which is almost invariably at its worst the first few steps out of bed in the morning or after one has been off his/her feet for a long period. After those first few steps (how many is “few” depends on the individual case), the severity of the pain usually subsides and normal walking or running can be accomplished without limping. By the end of the day (or a long run) however, the pain begins to return in many cases, though usually not as severe as in morning.
Symptomatic treatment follows the usual course: icing, anti-inflammatories (aspirin, Advil, etc.), but of course we always want to get to the underlying cause. While orthotics are often very helpful in correcting the abnormal pronation causing plantar fasciitis, I have found that many times the true culprit is tight calf muscles which limit ankle motion during mid and late stance. This causes a compensatory pronation in the foot, which for some unidentified reason seems to focus the stress in the plantar fascia. Thus, before I try orthotics with most plantar fasciitis patients, I will almost always try calf stretching exercises first and I recommend that if you come down with this injury you try this too before hopping off to your doctor.
Another treatment for this injury (as well as many others) is a technique known as cross-friction massage, which is what I’ll discuss next time.