There are only a handful of runners that I’ve seen that haven’t had a case of shin splints, in some degree whether it be mild shin pain to a full blown stress fracture of the tibia, at some point in their running career. This is one of the most common injuries known to runners, and it is curable and preventable. But first you need to figure out what type you have since they both have similar symptoms but have very different treatments.
Type 1: Medial Tibial Stress Syndrome (MTSS)
Just like the name says, there is pain along the inside part of your shin. It usually develops steadily over time and can get bad enough it will make you want to stop running. It is sharp or stabbing in nature and decreases a lot once you stop running and it almost completely gone in about fifteen minutes. You will also most likely find that the middle of your shin, on the inside, is tender or painful to the touch. This onset of pain comes on with a new training regimen or an increase in mileage. Running on hard surfaces or increased body weight, like a weight vest or pack, has been known to cause this type of shin splints. So what is causing this? It is caused by the Soleus Muscle, one of the calf muscles that attaches to the inside border of your shin.
The Soleus lies under the gastrocnemius, the big muscle on the lower leg but together these two are called the calf. The Soleus is made up of slow twitch muscle fibers which are used in endurance activities such as walking, standing, and yes running too. When this muscle gets overworked from a sudden increase in mileage or a new activity, it pulls on the medial (inside) of your shin. Your body doesn’t like this pulling and tries to stop the pain by laying down scar tissue where it attaches to the bone to make the connection stronger, which in turn makes the muscle tighter and the viscious cycle begins. This cycle will continue until you either get treatment or stop/change the activity for enough time for your body to heal properly. This will cause stress fractures of the tibia if something is not done about it.
Type 2: Exersional Compartment Syndrome (ECS)
The second type is also associated with an increase in mileage and/or starting a new running activity. This pain is on the outside, lateral, side of your shin that is often worse running down hill. It is a deep achy pain that can lead to foot slap while running. The pain is not diminished immediately after stopping your activity and can still be quite painful at rest fifteen minutes or more after stopping and is often described as a pressure or fullness in the lateral lower leg.
This pain is caused by an increase in pressure of the anterior compartment of the leg. The compartment is made up of the tibia and fibula, the lower leg bones, the ligament between these and the fascia that goes over the muscles. Inside of the compartment is the Tibialis Anterior and other muscles that lift the toes and dorsiflexes the ankle during the swing phase of your running gait. They also are used for a controlled lowering of your foot/toes after heel strike. Using these muscles requires more blood flow and nutrients which increases the size of the muscles. When they increase too much this increases the pressure inside of the compartment, which can increase to the point where it causes pain or even foot slap. Foot slap occurs in this type because the muscle are starved of blood and can’t remove the lactic acid buildup and the muscle fatigues. If the pressure continues to increase it can even effect the sensory distribution of the nerves that innervates the skin between your first two toes.
With MTTS pain, you need to decrease the amount of pulling the Soleus muscle puts on the shin. This can be done a couple of different ways. First off is by working the Soleus with soft tissue techniques such as myofascial release either by hand or with tools. Techinques such as ART, Grason, and IASTM, break up scar tissue between muscles, ligaments, and other tissues. This takes tension off of the shin attachment reducing the pain caused by the Soleus attachment. Other treatment options include gait analysis to reveal why this muscle is being overworked, which may be overpronation, rearfoot varus deformity, leg length discrepancies, or a host of other options. You should also decrease your training to allow the tissues to heal. If these issues are addressed, the recovery time and reoccurrence rates can be greatly diminished. Footwear and training analysis should also be evaluated to make sure they are designed for your specific needs. It is also recommended not to increase your mileage by more than 10% a week to decrease the likelihood of developing MTSS.
For pain caused by ECS the options for treatment are similar to MTSS since gait, poor footwear, and muscle tightness all can predispose you to this injury. Specifically, myofascial release, and other soft tissue techniques over Tibialis Anterior, calf muscles, foot and toe extensors and the compartment fascia will aid in reducing the pressure in the anterior compartment therefore reducing pain caused by this pressure. A decrease in training is also recommended. If this condition is not treated it will develop into Acute Anterior Compartment Syndrome.
Acute Anterior Compartment Syndrome, warrants immediate medical intervention since the pressure in the compartment gets so high that blood and nerve supply to the muscles, ligaments, bones to the lower leg and foot is cut off. The treatment for this is fasciotomy, a surgical intervention which involves cutting open a 4-6 inch section of the anterior compartment to decrease the pressure. The symptoms are similar to ECS, extreme pain, swelling, numbness and lack of muscle control of the foot, except they are more intense and DO NOT decrease in intensity with time, they only INCREASE with time.
If you are experiencing any of these symptoms you should seek the evaluation of a qualified health care practitioner to examine and evaluate your specific condition.