Plantar Fasciitis, fallen arch, overpronation… All sound familiar? I’ve heard these terms way too often as a clinician. Runners and triathletes are all too familiar with these diagnoses and are quick to find a way to resolve it. Because, quite frankly, runners and athletes can’t stay off their feet! That’s completely forbidden (insert snarky emoji). But what if the pain doesn’t resolve with conservative google solutions and youtube videos? Well, let’s take a look at the reason why you’re having the pain in the first place.
The foot is a common source of orthopaedic injuries because of the high amounts of load that take place in the foot. There is a unique interdependence of the bones, ligaments, and muscles involved in the foot to maintain stability. The foot is able to be a rigid lever to provide power transfer from the ground up. At the same time, the foot can also act as a shock absorber when it is hitting uneven surfaces that demand conforming and flexing to every nuance of a trail run. I want to pay particular attention to how the foot acts as a stabilizer.
Everyone has seen or heard that one person in the gym slapping away on the treadmill. You can literally hear every pounding of the foot that occurs on the poor machine. Part of the reason that occurs is that the person’s foot is not able to maintain its shock absorption capabilities through the gait cycle and throws in the towel midway through.
The foot is designed to walk on. We have 3 stance phases of movement during the normal walking gait cycle: heel-strike, mid-foot stance and toe off. The foot is most effective at transferring forces from the posterior leg muscles to the ground at midstance phase. When there is a collapse of the arch that supports the bones of the foot during the gait cycle, problems occur. The involved ligaments and tendons that provide support to the foot become too flexible to effectively push off from the ground. When the small intrinsic muscles of the foot are not able to do its job under the load of the entire body, the flat foot becomes an even bigger problem up the chain into the knees or the back. That is why it is important to address these issues before it becomes an even bigger problem.
One of the most important supporting cast members of the foot is the posterior tibial tendon. This tendon attaches the posterior leg muscles to the bones on the inside of the foot. Its primary function is to hold up the arch and support the foot during walking. Dysfunction of this tendon can occur from repetitive use or from high impact activities such as running.
How we assess and diagnose for posterior tibial tendon dysfunction includes some of the following tests:
-Pain with palpation or tender to touch
-Too many toes sign: when looking at static foot posture from behind, the 5th toe and part of the 4th toe should only be seen. If you see more than that, you have a positive sign and considered to have a flat foot deformity
Hindfoot eversion: Again when looking from behind, the heel may tilted outward
-Limited dorsiflexion: restricted upward motion of the foot will indicate tightness of the calf muscles which contribute to midfoot loading
-Single Leg Heel Raise (SLHR) Test: Try this test out on yourself. Stand on one leg and attempt 20 heel raises. You should be able raise your heel off the ground without aberrant movement of the heel outward. There should also be no pain indicated with this test. If you do, then there may be an indication of posterior tibial tendon dysfunction
Although studies show that not all patients with posterior tibial tendon develop weakness, there is a correlation of weakness with flat foot mechanics during gait (http://www.ncbi.nlm.nih.gov/pubmed/20371019)
This is where I come in and get on my soapbox. When someone comes into my clinic and has shoulder pain, instability or weakness I give them strengthening exercises. If someone comes in for back pain, I give them stabilization strengthening to improve their pain and stability. If someone comes in for knee pain and has instability, I give them strengthening and stabilization. But for some reason, the industry standard for foot dysfunctions such as plantar fasciitis, flat foot deformity, or posterior tibial tendon dysfunction is that we put them in a boot or make them a custom orthotic. Sure, I am totally on board for giving a person some offloading if it is an acute injury and they need to clearly unload it, but if we don’t actually stabilize the foot we are actually telling the nervous system to shut off all input to the muscles of the foot, particularly the intrinsic stabilizers (small muscles of the foot). In the long run, this does nothing for the patient and simply puts a temporary Band-Aid on it. So lets look into ways we can develop some of this intrinsic strength back into the foot and provide stability where we need it. I’m going to go through some basic exercises that you can do to help support the foot and set it up for success
I love this exercise because it “turns on” the small intrinsic muscles of the foot, particularly the flexor hallucis brevis and extensor hallucis brevis. These are muscles that should automatically turn on as you walk and provide stability to the longitudinal arch (main arch) of the foot. So try this exercise.
Stand shoulder width apart without shoes
Start with putting pressure down with the lateral four toes of the foot and lift only the big toe without losing pressure of the other four toes
Now switch it up and press down with the big toe and raise the lateral four toes.
Repeat this at least 15 repetitions and perform 3-5 sets
For those of you that are really weak, a common complaint is that you’ll get a cramp into the arch of the foot. Good! It’s turning on
Seated Windshield Wiper:
This exercise specifically targets the posterior tibial tendon that I mentioned earlier
Sit with the foot flat on the floor and facing straight ahead. Rotate the affected foot to mimic a windshield wiper blade
Pivot the foot outward and touch the inside edge of the foot to the floor (A)
Then rotate it inward and touch the outside of the foot to the floor (B)
Perform at least 20 repetitions with 3-5 sets. Twice a day
If it is too easy, add in a resistance band to the exercises to feel the muscles turning on
This exercises is easy and effective to target the functional range of the target muscles. It’s pretty straight forward.
Start with feet plantarflexed (stand on the balls of your feet)
Walk forward and keep your heels from touching the ground for approximately 10-20 yards. Eventually progress to 100 yard distances
There is some good literature out there showing positive results from conservative management. One study by Alvarez et al (http://www.ncbi.nlm.nih.gov/pubmed/16442022) laid out a specific exercise protocol that targeted posterior tibial tendon dysfunction with positive outcomes. I believe that if you can nail these exercises and work on improving foot dynamics, you will gain control of the foot once again and power through every stride. I am not against arch supports and orthotics completely, but I want to emphasize that the muscular support system is crucial in providing the stability through the foot to set it up for success. It really does depend on the individual and what symptoms they present with. If you have any questions on this, please feel free to contact me
In my next blog, I will be talking specifically on how the gait cycle is altered in cycling and the biomechanics associated with the foot during the pedal stroke. This is extremely important in considering how the foot-pedal interface is looked at biomechanically.