What Causes Shin Splints? (Part 1 of 4)

Dr. Alex Earl, DC shares insights and simple strategies to help competitive and everyday runners like you deal with shin splint pain in the Wheaton, Glen Ellyn, Carol Stream & Winfield area.

Every Spring, for the past four years, runners from local high schools and competitive runners training for a race come to our office in Carol Stream, IL with what quickly appears to be shin splits. There are two kinds of shin splints but several different causes of shin splints plaguing runners, soccer players, lacrosse athletes and many, many more. 

Regardless of their goals, activities or sport, they all ask the same question: "What is causing my shin splints?" 

So much so, I decided to map out the full clinical picture of shin splints. This will be the first of a four-part blog series addressing the causes of shin splints. 

Please note the use of the term "shin splints" is referring to both anterior (front) shin pain and posterior (back) shin pain. For the sake of this article, the two types of shin splints will be used interchangeably so as to avoid any unnecessary confusion.

Part 1: Busting the 9 Current Myths about Shin Splints

To start off, we need to address the more frequently cited causes for shin splints. These come to us in the form of other healthcare professionals, health websites, blogs, podcasts, as well as directly to athletes from their parents, friends and coaches. With so many thoughts and opinions on the topic, it is very challenging to know who to trust. 

We have taken upon ourselves to help decipher through the noise of information online by ... wait for it... providing information online! 

This blog series is specifically designed to relay a taste of the information, the style in which we deliver it, and the solutions moving forward that we deal with on a daily basis at our Carol Stream clinic. We help runners deal with shin splints and keep them playing when most others advise them to stop, rest and ice. 

[For more information on why this is poor medical advise, please read my last blog entry on this very topic and why rest & ice is NOT always the best idea!]

The 9 Current Myths About Shin Splints: 

1. Weakness of the Shin Muscles

Most people assume muscle weakness as a cause for their pain. The evidence published on the topic of muscle weakness suggest otherwise, though. When a patient says, "my shins must be weak" as an explanation to their pain, I nearly always reply with, "Compared to what?" In the absence of neurological diseases and disorders, muscle weakness is very difficult to define and is often a contentious word tossed around by both medical providers and patients but with completely different definitions in mind. In our opinion, muscle weakness is insufficient and we suggest muscular endurance be used instead. As you will see in the follow up blog entries in this series, if we pose a problem or address a myth, I will also provide a solution. 

2. Muscular Imbalances

Contrary to popular belief, muscular imbalances are not evil and are very poorly correlated with painful conditions, such as shin splints. Runners have imbalanced muscles all over their bodies, but does it mean we can accurately state the group of muscles involved in shin splints are the cause of pain when there are other areas in the same body which are imbalanced but do not create pain?

3. Asymmetry of the right leg vs. left

Of all the "myths" we've heard over the years, the strongest argument against my views on the topic could be this one. With that being said, there are dozens, if not hundreds, of professional athletes, competitive marathoners, hockey players, baseball players, etc who have asymmetries and yet, they don't develop pain from shin splints. Take, for example, Leo Messi. Arguably the GOAT (greatest of all time) has a massive asymmetry in his right leg compared to his gifted left leg.  One of the normal features of human beings is our individual asymmetries. Each one of us posses small, insignificant differences between the right side and left side of our bodies. A fair question to ask would be, "Why does the asymmetry become a cause of pain when it is present in nearly everyone? Is everyone with any asymmetry experiencing pain? No! Therefore, it is a conclusion which lacks sufficient evidence to say it is a cause of pain. 

4. "Glutes not firing"

Unless you've experienced significant neurological compromise, such as a nerve injury, spina cord injury and/or a neurological condition such as MS or ALS (Lou Gerhig's Disease", muscles not "firing" is a moot point. There is no significance on the order of muscles firing either. Muscle contracts and "fires" based on the demands we put on the motor (movement) system. If we desire to stand up, walk across the room and pick up a glass of water, we are unconsciously using muscles in order to complete those tasks. Exercise is no, different. There are hundreds of literature articles looking into how motor control exercises affect painful conditions, and yet, only a few have shown that they actually change the way the muscles are firing. For example, in a hallmark study, Hodges and his group showed that low back muscle contractions were delayed by a milisecond in patients with low back pain compared to those who did not have low back pain. This became *the paper most cited by clinicians about the timing of muscle function. Since that paper, there have been dozens of other studies showing that specific exercises designed to change muscle contraction patterns failed to do so BUT those participants studied still DID show an improvement in their pain - it reduced. So, if we can reduce pain by strategic exercises but not change the muscle firing patterns, does it matter? Our vote is yet, it matter in what we relay to our patients. We are movement optimists and we will not cater to the negativity in the healthcare world. There's already plenty of that to go around. We would much rather communicate the important steps our athletes and clients are making towards solving their pain so they can get back to their activity, whether that is running, soccer, basketball, or football. 

5. Weak Core

A "weak" core has been the victim of many year's worth of low back troubles. It has even made its way into the cause of lower extremity conditions, including shin splints. A patient came to our office after visiting a local therapist after he was told his weak core was the reason he had shin splints. Now, we could make an argument for why this could be correlated but we wouldn't go so far as to say this is what caused his shin splints. Correlation implies a mutual connection, whereas causation implies the action of causing something. A good example of this distinction is that of ice cream sales and crime. Both increase during the summer months. But we cannot say that ice cream sales increase crime.  Having a weak core causing shin splints is like saying ice cream sales cause crime in the summer months. 

6. Over-pronation

Try going to a running store and NOT have the retail sale associate tell you that your feet pronate. It won't happen! With that being said, I must admit has changed in the past few years. Thanks to the work of some really smart people, who ask really critical and thought provoking questions, I've been keen to modify my original stance on pronation. After watching video of dozens of elite runners, it blew me away how many of them pronate to the point of concern. And yet, they were professionals making serious amounts of money and running at an incredible pace. If I were treating them, would I have tried to alter their over-pronation? If so, many would argue I would be making them a better runner, while many others would conversely argue I would be making them a worse runner! I've landed on the "do nothing if it ain't broke" approach. If Usain Bolt came to our office back in 2008 (arguably the peak of his career), would I have addressed his intense over-pronation? Knowing what I know now, I would have added some of our Running Drills to Master for him, BUT I would not make a big deal about his feet and toe displacement.. which leads me to my next point...

7.  Bone-out-of-place

The bone out of place theory makes logical sense, except that it doesn't make clinical sense when discussing patients with pain. Sure, a big toe that is slightly pointed laterally as the result of years and years of little wiggle room in modern shoes hasn't helped the situation, BUT it certainly has not become (all of a sudden) the reason people start developing shin splints. After all, with every new patient we see in our office, we do a thorough movement analysis on the first visit. The number of patients with low back, hip, knee and foot/ankle troubles with perfectly positioned feet is 50%. Half of our patients do not exhibit deformed toes and feet but the other half show anywhere from mild to severe changes in their feet and toes. We find this as a clinical data point but, again (and I know I am sounding like a broken record here) this is insufficient evidence to say it is the cause of shin splints. 

8. Poor Posture

Poor posture gets blamed for just about every musculoskeletal condition on the planet. Unfortunately, upper and lower crossed syndromes were theoretical in nature by Pr. Vladimir Janda and were the greatest contribution to the field of rehabilitation and sports performance at the time - in the 1970s and 1980s. Having learned first hand from Pr. Janda's protege, Pr. Pavel Kolar back in 2016 on a week long intense training course at his hospital in Prague, I got to ask Pr. Kolar about Janda's work with postural analysis as an explanation for the cause of pain. Pr. Kolar assured myself and the rest of the attendees at the course that the movement system is a representative of the brain and while movement patterns can be enhanced they are quite unpredictable at determine the root cause of patient's pain. His current emphasis is on improving movement efficiency, rather than corrective postural alignment issues. An example of this would be isolated hip range of motion, such as internal rotation without the use or movement of the low back. We would agree! We feel narrative needs to switch from pointing out postural flaws and instead focus on challenging the right tissues at the right time to improve the efficiency of movement in order to be more prepared to handle the stress of running the next time out. 

9. Need an orthotic/insert in your shoe

This myth is cut from the same cloth as Myth #6 because it addresses the quick fix to the over-pronation problem. I should probably clarify I am not opposed to orthotics, especially when used under specific and temporary situations. Some people respond well to orthotics and others rely exclusively on them for normal day to day function. I would also like to concede the cases where individuals have sustained trauma to a long bone, such as the femur (thigh) or the lower leg, such as the tibia. If this injury took place during childhood, it is very likely one leg would have grown at normal rates while the other was delayed due to the injury. This is one way in which a leg gets physically longer than the other one. In these cases, an orthotic in the shorter leg is a smart, clinical decision. In my opinion, these two are completely different clinical presentations - unless, of course, the patient has both! 

So there you have it. My attempt at dispelling the most frequently cited causes for shin splint pain. In the coming weeks, I aim to redirect the conversation towards the solutions of the shin splint problem, and here's a hint... It's NOT rest and ice!

Do this next:

1. Share this blog with someone you know who would find this information useful.

2. Email our office if you are interested in the Running Drills to Master mentioned in the blog. Email us at: info@myactiverestoration.com

 3. Keep an eye out in your inbox next Wednesday for the 2nd Installment in our 4-part blog series. 

Dedicated to restoring you health. 

Dr. Alex Earl, DC DACRB