PLANTAR FASCITIS

Runners, particularly distance runners, commonly suffer from Plantar Fascitis, an inflammation of the plantar fascia of the foot (see figure I).  The function of the plantar fascia is to help hold up the arch along the inside of the foot.  When running, we strike the ground with 2 to 5 times body weight at approximately 1500 foot falls per mile.  With every foot strike the arch drops (pronates) to unlock the foot for impact absorption.  As the arch drops the plantar fascia is stretched, repeated stretching of the fascia can cause irritation and inflammation.

The hallmark symptom of plantar fascitis is sharp pain underneath the heel, especially during the first 10-20 steps out of bed in the morning.  This begins on the mornings after your long runs only.  It progresses to a constant pain while walking, and a broader area of the foot will be affected. 

Plantar fascitis may have intrinsic and extrinsic causes, or a combination of both.  Both causes result in increased stress on the fascia.

EXTRINSIC CAUSES:

Extrinsic causes are due to training errors that increase the stress on the plantar fascia beyond the body’s ability to adapt.  Too great an increase in run frequency or duration produces too many repetitions.  Increased pounding causes increase in the amount of force created at each heel strike, this occurs during speed work or on harder running surfaces. 

INTRINSIC CAUSES:

Intrinsic causes of plantar fascitis are related to faulty foot biomechanics, which result in overpronation (flat feet).  The quicker and farther your arch tends to drop while running, the more likely it is for those extrinsic factors to produce irritation.  Weakness of other supporting structures designed to assist the plantar fascia places more stress on the plantar fascia.  As we move forward over our planted foot, the front of our foot and toes move closer to our shins.  This is called dorsiflexion (see figure II).  At least 10 degrees of dorsiflexion is necessary for good running form and may be restricted by a tight heel cord (calf muscles).  The body compensates for this by increasing pronation.

A WORD ABOUT HEEL SPURS:

Heel spurs are created as the body combats chronic irritation to the plantar fascia by depositing the hardest substance it can to protect the area.  This substance is bone, and spur formation occurs at the origin of the plantar fascia under the heel.  Since this is the site of pain, it is often pointed to as the cause.  This is not usually true, as it is a reaction to the cause – faulty mechanics.  While removal of the spur occasionally decreases the pain, if the faulty mechanics are not corrected, pain and spur formation may recur.

WHAT YOU CAN DO:

Symptom relief is beneficial for your recovery, but the cause must be addressed or recurrence is likely. 

Symptom Relief: the following should alleviate pain and inflammation.

1. Icing the painful area will reduce inflammation more efficiently than oral anti-inflammatories:
   1. Ice packs – 20 minutes on, 40 minutes off.  Repeat 3-5 times a day.
   2. Ice massage – fill a paper cup with water and freeze it.  Peel back the cup and massage the ice directly on your skin for 8-10 minutes, again off for 40 minutes.  Repeat 3-5 times a day.
2. Ice should always be applied after a run while tissues are recovering.
3. Compression Massage:  rolling your foot back and forth over an object like a golf or tennis ball helps break up adhesions and disburse swelling.  The best approach is to use an empty glass coke bottle, stick it in the freezer (there’s that cold thing again) and use for massage as necessary.  This should be performed several times a day for 5-10 minutes.
4. 90° Night Splint:  Our bodies do most of their healing at night while sleeping.  Sleeping on our stomachs, for example, causes our toes to point down, shortening our plantar fascia.  This causes scar tissue to lie down in a shortened format.  The first few steps in the morning stretches the fascia, tearing the newly formed scar tissue and producing intense pain during the first few steps in the morning.  Splinting the ankle at 90° while sleeping keeps the fascia from healing in a shortened position at night and has proven to decrease healing time.

CORRECTING THE CAUSE:

Extrinsic Causes: Address errors in your training program.

1. Active Rest – Cross training will allow you to train while taking the pounding stress off your injured fascia.   It will also enable you maintain your aerobic base and prevent you from driving your significant other crazy with your grumpiness!  Swimming, cycling, or using cross country ski machines and elliptical machines available at your local health clubs are great sources of aerobic exercise with differing amounts of pressure on the plantar fascia.
2. Frequency – Recovery time naturally increases with age, so you may need to take more days off than you used to.  Proper nutrition also becomes more important with age, to provide the body with the building blocks to repair itself.
3. Intensity – Try not to follow a speed session day with a run course with long or steep downhills.
4. Duration – A general rule is not to increase your long slow run by 1-2 miles per week, or your total weekly mileage by more than 10% per week.
5. Type – Softer surfaces like packed dirt are a good alternative. Running on packed dirt trails is the best, let’s give it a factor of 1, asphalt would have a factor of 2, concrete a 3.  That’s how much harder concrete is than asphalt.  However, training for a marathon on dirt and running it on the streets will predispose you to injury because your body will not be prepared for the increased pounding.

Intrinsic Causes: Intrinsic causes are due to problems with biomechanics and require some form of functional correction.  These conditions tend to recur even after prolonged rest.

1. Stretch!!:  I’ve been treating runners for over 13 years now and I have yet to meet a runner that says “I think I stretch too much.”  Stretching your calf muscles should always follow your runs, but as the most dense muscle tissue in your body, and should be stretched frequently throughout the day.  One calf muscle crosses the knee joint (gastrocnemius) and one does not (soleus), so they must be stretched separately.  All stretches should be held for 30 seconds and performed throughout the day.  Face a wall to lean into and place your right foot back in a lunge position, toes facing straight ahead or slightly inward (pigeon toed).  Press your right heel into the floor, keep your knee straight, and lean your upper body towards the wall.  Be sure to keep your heel down on the floor.  Keeping your knee straight will stretch the gastrocnemius, which should be felt behind and below the knee.  To stretch the soleus, bring your torso away from the wall and bend your right knee.  Bring your torso forward again, keeping the back knee bent, heel pressed to the floor.  You should now feel the stretch closer to your heel.
2. Strengthen:  Heel raises are the only exercises that have been shown to strengthen the structures that support the arch.  Like the stretches, they should be performed with the knee straight and the knee bent.  I recommend doing single leg heel raises off the edge of a step to take the muscle through a full range of motion.  Performing them in a doorway without holding on will build balance and coordination through a limited range of motion.  And performing skipping drills when tolerated by the injury will incorporate them at a speed similar to running.
3. Proper Footwear:  Overpronation can often be corrected by changing to a “motion control” or “stability” shoe.  Every shoe company makes them, most commonly by incorporating a “dual density midsole” into their shoes.  The sole will have cushioning along the medial side (inside) and under the arch of the shoe that is stiffer than the cushioning towards the lateral (outside) of the foot.  These densities are usually different colors and easy to spot, but I would recommend going to a specialty running store for advice.
4. Orthotics:  Orthotics are foot beds placed in the shoe that are designed to reduce or eliminate overpronation and the stretch it places on the fascia.  These can vary in price from $15.00 to $500.00 and can be bought generically over the counter or made completely custom for the individual.  As a provider of custom orthotics, I’ve compared a lot of companies and approaches to orthotic prescription.  Here’s what I recommend:
   1. Not everyone needs orthotics!  Try to find someone who can objectively evaluate your needs (not an orthotic store owner).  In our clinic we send patients out for new shoes and try to get the correction there.  We then tape our patient’s arches to discern whether it reduces the pain.  This indicates if orthotics will help.
   2. All orthotics are not the same.  Over the counter ones are not always cheaper than custom sets, and custom does not mean completely custom.  Some companies claim to provide custom orthotics, when in reality they pull from ready-made forms, which most closely match the patient’s needs.
   3. Your orthotics are only as good as the casting procedure used.  Ask the benefits of the procedure used by your orthotic provider over other casting procedures.
   4. Last but not least, if you have a pair of orthotics, custom or otherwise, if they make enough of a difference to help overpronation, it should hurt to only wear them running.  If you continue to experience pain despite your orthotics, they may not be providing enough of a correction.

Plantar fascitis can be a complex problem not often resolved simply by rest.  Early evaluation and proper treatment are beneficial, while prevention through stretching and strengthening are invaluable.