This past week I posted a case study which generated a lot of comments both good and bad. I would like to use this opportunity to respond to those who have questions as to how this occurs as well as to elaborate on my position in changing the way we look at biomechanics and foot function in medicine today.

First and foremost I would like to introduce myself. I am a podiatrist with 3 years of residency training in reconstructive foot and ankle surgery. I practice in Akron, OH where I am part of a multi-specialty group – Northeast Ohio Medical Associates. I have been practicing for 10 years and am proud to be part of a busy well rounded practice exposed to all aspects of foot and ankle pathology. I have been a runner my entire life and have a desire for longer distance events such as the marathon. The focus of my practice had never been to treat runners although it has become an important part of my practice recently. So important that I have treated runners from all over the world both in my office and on-line. My involvement in running barefoot and with minimalist type shoes began 5 years ago when I was able to resolve a 10 year old injury I was suffering from to my foot. This opened my eyes to what research had been done on running shoes to date and how we really knew very little about why we use shoe gear the way we do. I used to prescribe running shoes with motion control and stability mid soles based in the prehistoric paradigm of fitting running shoes based on foot type. I encourage you medical professionals reading this to not do so as there is no medical based evidence to support it, and you can be held liable for not helping your patient. There are accounts of this happening to physicians.

It’s very unfortunate as to some of the comments I’ve received from those who claim to be professionals. So unprofessional that I cannot even post the comments. I’ll gladly accept the criticism from others who disagree with me. That’s what keeps us all thinking. To remain status quo would mean no advancements would be made in medicine. I am not attempting this change for financial reasons. This is helping people. Consider that 40 years ago most physicians thought the cause of heel pain was a spur and they excised them surgically. It was later discovered to be plantar fasciitis. Reducing obesity was aimed at eliminating fat from our diet only to find out that increasing the amount of carbohydrates made people even fatter. We have embarked on a point in time when shoes and orthotics are not doing what we once thought they were doing. We are obtaining a better understanding of how our feet respond to stress without support or shoe gear. In fact, we have realized after years of observation that what we thought was support was merely just preventing the foot from functioning the way it was intended to. One of the things we have to thank is the internet. The internet has joined millions of people together and allowed them to share their experiences with running and what works best. Call it anecdotal, but we now have the ability to hear what works for runners in terms of shoe gear like we never have before. It’s really no different then a retrospective study other then he whole world is involved as opposed to a select number of people who can be reached from a defined population.

….in a Retrospective Cohort Study, all the events – exposure, latent period, and subsequent outcome (ex. development of disease) have already occurred in the past. We merely collect the data now, and establish the risk of developing a disease if exposed to a particular risk factor.

As more and more runners began experimenting with barefoot running they began sharing their experiences on blogs and discussion boards. Others read about it and tried it. The critics, whom by the way are vested in financial gains from orthotics and shoe companies, say its crazy. Well, in the words of Steve Jobs, “the people who are crazy enough to think they can change the world, are the ones who do”. Hundreds of thousands of runners who have improved their form and resolved injuries by running barefoot is anecdotal. The literature is now beginning to catch up with this as seen in some recent published studies (Goss, Rixe, Altman,)

Those opposing running in minimalist shoes will make the claim that there is an increase in risk for injury. A study published in the July 2011 edition of Orthopedics associated stress fractures in two (yes TWO) runners who immediately began running in barefoot-simulating footwear. This is deemed scientific? Two subjects both of whom did not gradually transition. Those opposed to minimalist running shoes, as well as the media, will use this study and argue that “minimalist shoes create stress fractures”. Once again TWO subjects. I help at least two people everyday in my office by advising minimalist shoes and have yet to see a stress fracture as a direct result. Remember. There are two reasons stress fracture can occur. Overuse and osteoporosis. Lack of cushion in a shoe will not create a stress fracture. Wolf’s law of adaptivity has proven this years ago.

Wolff’s law is a theory developed by the German anatomist and surgeon Julius Wolff (1836–1902) in the 19th century that states that bone in a healthy person or animal will adapt to the loads under which it is placed.[1] If loading on a particular bone increases, the bone will remodel itself over time to become stronger to resist that sort of loading.[2] The internal architecture of the trabeculae undergoes adaptive changes, followed by secondary changes to the external cortical portion of the bone,[3] perhaps becoming thicker as a result. The inverse is true as well: if the loading on a bone decreases, the bone will become weaker due to turnover, it is less metabolically costly to maintain and there is no stimulus for continued remodeling that is required to maintain bone mass.[4]

So then how is the study published in the July 2011 edition of Orthopedics associating stress fractures in two (yes TWO) runners who immediately began running in barefoot-simulating footwear deemed scientific? I ask that same question. And with only two subjects? Not to mention both cases were the result of zero transition to this type of shoe and running form but an instant “lets put these shoes on and run”. I could have hypothesized they would get injured. These are the types of articles the critics respond with. Do you see what I’m getting at? I know I recently presented a case that only involved one runner. I did this so others can visualize what can occur. I have the data from a statistically significant amount of runners with objective findings which will eventually be published. I too could post cases of runners who get injured as I see them daily in my office. And yes some of them are in minimalist shoes, but it’s the way they’re running and more so their training patterns which cause the injuries. I was trying to make a point that this is safe, it does help to improve someone’s form indirectly, and there are long term benefits from it.

As for my financial gain from posting the case study? Really? People are going to make this statement? Trust me, I can make more money in my office by dispensing one custom orthotic to a patient then any of the money that will come as a result of my blog. This blog is to help people. My practice is mainly a surgical based practice in comparison but I love to help runners because I too am a runner. I could have easily chose to start a blog about foot and ankle surgery but that’s my job! This is a hobby and it’s helping people!

Before we discuss the main focus of this post I would like to address one more thing. Someone had made the comment that this is Photoshop trickery. Trust me, I have better things to do with my time then to put my reputation on the line with falsified information. I will be speaking about running at the American Podiatric Medical Association National Meeting this July. This is not just some random blog post to get attention. I’ve been blogging for 3 years and have been lecturing on this topic now for over 5 years. This post just happened to get the attention of a lot of readers.

So, I will try to respond to the critics as well as explain how the foot became stronger in this specific cast study that I presented. Below are references which explain my reasoning. I will also do my best to put a lot of the scientific and medical terminology into words that most will understand.

The Abductor Hallucis Muscle
The muscle that is responsible for the majority of the foot structure improvement seen in this situation is the abductor hallucis muscle. It is a muscle commonly overlooked in the foot and rarely does it even get recognized or discussed with any foot pathologies. Recent literature has demonstrated it’s importance to the foot, especially to the medial longitudinal arch.(Wong, Fiolkowski, Headlee, D.-Y. Jung). Let’s examine the anatomy of the abductor hallucis and then review how it may be more involved with the injuries seen in the foot.

The abductor hallucis muscle originates on the posteromedial aspect of the calcaneous and inserts into the medial sesamoid of the hallux or proximal phalanx (Kendall, McCreary, Provance, Rodgers, & Romani). In laymen’s terms it is a muscle that runs to from the inside of the heel bone through the arch and to the inside edge if the big toe. The action of the abductor hallucis is to flex and supinate the first metatarsal, invert the calcaneous, external rotation of the tibia, and elevation of the medial longitudinal arch (Wong 2007). It also contributes to stabilization of and supination of the midtarsal joint against the pronating force of ground reaction during propulsion (Mann). So basically as it shortens, the arch height is increased from the heel bone turning inward and the long bone to the great toe increasing it’s angle to the ground.

Numerous researchers have demonstrated that the abductor hallucis muscle supports the medial longitudinal arch and recommended strengthening of foot intrinsics to prevent overuse injuries in those who present with excessive pronation. Fiolkowski et al. demonstrated with electromyography that the abductor hallucis muscle plays and important role in supporting the medial longitudinal arch and control pronation during static stance (Fiolkowski et al). Headlee demonstrated that after the abdcutor hallucis muscle is fatigued there was an increase in navicular drop. This was also confirmed by Fiolkowski after witnessing increased navicular drop by blocking the tibial nerve. For those not in the medical field, the navicular is a kidney shaped bone in the middle of the arch that is used as a reference point in measuring arch height. The more it drops the less arch is present. These studies were able demonstrate an increase in arch height through contraction of the abductor hallucis muscle.

So as we can see, the abdcutor hallucis muscle plays an important role in maintaining arch height as well as controlling excessive pronation. In fact we have seen that increased drop of the navicular bone is the result of a weak or inactive abdcutor hallucis muscle. Strengthening this muscle can aid in treating and preventing overuse injuries. It should be viewed no differently then the posterior tibial muscle and tendon. This muscle is commonly blamed for collapse of the arch and condition commonly referred to as posterior tibial tendon dysfunction. Shin splints are also sometimes a result of overuse of the posterior tibial tendon. Something to consider however is what fails first? The arch or the posterior tibial tendon? The integrity of the arch is maintained by a combination of the bones, the ligaments that connect the bones (specifically the spring ligament or calcaneonavicular ligament), and the intrinsic muscles of the foot i.e. the abductor hallucis muscle. The posterior tibial tendon only begins to work harder when the aforementioned structures have failed and this leads to the tendonitis or tendonopathy.

The question this poses is, should one rely on external support such as an orthotic device to maintain or support the arch, or should the focus be to strengthen the intrinsic muscles of the feet, specifically the abdcutor hallucis. Do-Young Jung demonstrated that the short foot exercise is a useful exercise in increasing its strength, more so then toe curls which also provided a strength increase (D.-Y. Jung). A study in 2005 involving an early version of the Nike Free demonstrated an increase in muscle mass of the abductor hallucis muscle after running in the shoes for 5 months.

Something else to consider is muscular tone. Muscle tone is described as a measure of a muscle’s resistance to stretching while in a passive, resting state. It is also used to describe the continuous, partial contraction of muscles while in a passive resting state. For example, when external force is applied to a passive muscle, muscles will increase in tension due to the partial contraction, reflexively responding to avoid stretching (2). A weak gluteus medius muscle (buttock muscle) or thoracic (upper back) and lumbar (lower back) muscles can lead to poor posture. Can the same be said for the abdcutor hallucis?

If significant strength gains a achieved in the abdcutor hallucis, will increased tone result in an increased structure of the arch? The above studies demonstrate increased support of the medial longitudinal arch during static stance.

In the above models, one would question as to whether or not the arch could be returned to a “normal” arch. Normal arches a variance of ALL arch types. Someone can possess a flat arch and have no symptoms whatsoever. Should this persons flat arch the. Be considered a variant or pathologic? More then likely arch types and their variants have been overplayed in medicine to the point where they are over analyzed and treated when unnecessary resulting in the true problem being overlooked. In this case being weak foot musculature leading to poor form which is potentiated by motion control shoes and orthotics. The result is a runner who does not look as closely to training patterns and form only to rely on shoes and inserts. If one shoe doesn’t fix the problem they try another.

Knowing the abdcutor hallucis muscle abducts the great toe or hallux would also lead one to think that by increasing its tone a reduction in a bunion deformity (hallux valgus) could result. I have seen this anecdotally as well. In fact, many runners who initially began running in Vibram FiveFingers were commenting on how their big toe had “moved over” and their bunion was not as bad as it was previously. The bump was still present from the metatarsal head, but the angular deformity from the big toe had improved.

I think it’s pretty clear that the research does demonstrate that foot structure can be influenced by strengthening the intrinsic musculature. As to what degree and whether or not this can have a positive effect on treating and preventing injuries still needs to be established. I agree that the “proof” or scientific evidence being put forward on my blog as well as in the world of running is anecdotal. However, as I have demonstrated, you can’t always use the peer reviewed published studies as proof. If you do not agree that a study with only two subjects which “demonstrates” stress fractures in runners wearing minimalist shoes is bogus and less valid then the anecdotal evidence others are presenting then please do not attack me personally and stick with your own beliefs. I have presented scientific studies in no different manner then what those have used against me. Some will say I am “cherry picking” my articles. For those who don’t understand how one writes an article to be published, you reference articles published by others which support your case or research. I just think it’s rather amusing that when I make my case with referenced articles I am accused of cherry picking.

In summary, I am trying to help runners resolve injuries and I am having more success with the approach I have been teaching my patients the last 4 years. I have used orthotics and have used the old paradigm of fitting running shoes based on foot type and have far less success then my current practice approach.

Kendall, F. P., McCreary, E. K., Provance, P. G., Rodgers, M. M., & Romani, W. A. (2005). Muscles: Testing and function, with posture and pain (5th ed.). Lippincott Williams & Wilkins.

2. https://www.boundless.com/physiology/muscle-tissue/control-of-muscle-tension/muscle-tone/

Wong, Y. S. (2007). Influence of the abductor hallucis muscle on the medial arch of the foot: a kinematic and anatomical cadaver study. Foot & Ankle International, 28, 617e620. J Foot Ankle Surg. 2008 Mar-Apr;47(2):89-95. doi: 10.1053/j.jfas.2007.10.015. Epub 2008 Jan 16.

Mann, R., & Inman, V. T. (1964). Phasic activity of intrinsic muscles of the foot. Journal of Bone and Joint Surgery (Am), 46, 469-481.

Fiolkowski, P., Brunt, D., Bishop, M., Woo, R., & Horodyski, M. (2003). Intrinsic pedal musculature support of the medial longitudinal arch: an electromyography study. Journal of Foot and Ankle Surgery, 42, 327-333.

Headlee, D. L., Leonard, J. L., Hart, J. M., Ingersoll, C. D., & Hertel, J. (2008). Fatigue of the plantar intrinsic foot muscles increases navicular drop. Journal of Electro-myography and Kinesiology, 18, 420-425.

D.-Y. Jung et al. A comparison in the muscle activity of the abductor hallucis and the medial longitudinal arch angle during toe curl and short foot exercises. Physical Therapy in Sport, 12, (2011) 30-35.

Goss DL, Gross MT. Relationships among self-reported shoe type, footstrike pattern, and injury incidence. US Army Med Dep J. 2012 Oct-Dec:25-30.

Rixe JA, Gallo RA, Silvis ML. The barefoot debate: can minimalist shoes reduce running-related injuries? Curr Sports Med Rep. 2012 May-Jun;11(3):160-5.

Altman AR, Davis IS. Barefoot running: biomechanics and implications for running injuries. Curr Sports Med Rep. 2012 Sep-Oct;11(5):244-50.