If you’ve ever experienced tight, swollen, and painful shins during or after exercise, especially if you are new to exercising, you may have mistaken them for shin splints when they are in something that can be much more severe. These symptoms are part of a condition called exertional compartment syndrome. Both athletes and recreational exercisers can experience them. Compartment syndromes can result in severe irreversible nerve damage, cell death, and even loss of the lower limb. If you have any of the symptoms outlined in this video, consult a doctor immediately.
For those in need of more in-depth medical information on compartment syndromes and other musculoskeletal conditions, I would recommend Essentials of Physical Medicine and Rehabilitation by Frontera and Silver.
What is Acute and Exertional Compartment Syndrome?
A compartment syndrome is a type of injury that could easily be confused with shin splints. Although shin splints are often used as a wastebasket diagnosis for any pain of the shin related to activity, there is a specific condition that is considered to correspond to what we commonly call shin splints, and this is MTSS, or medial tibial stress syndrome. Compartment syndromes are much more serious than common shin splints, so it is important not to confuse them.
Before I explain compartment syndromes, I’ll explain what a compartment is. A compartment is any anatomical space in the body that has certain defined and nonyielding borders. The compartments we are talking about in compartment syndrome are formed by the fascia that covers a group of muscles together with their nerve and blood supply, and this is usually the part of the anatomy that is meant by the word compartment. For instance, you might read about the anterior or posterior compartment of the arm or the leg.
Acute Compartment Syndrome
The most common site of acute compartment syndrome is the anterior, or front portion of the lower leg, which is the part we call our shin, although it can occur in other areas. An acute compartment syndrome is one that comes on suddenly and has severe symptoms. This is commonly caused by a direct blow to the front of the lower leg, such as being struck by another player’s foot in a sporting event. This can lead to a muscle contusion, or bruise, that causes excessive pressure to build up within the confined space of the fascia, and it obstructs the flow of blood both into and out of the muscles, which could lead ultimately to the death of cells. It could also be caused by highly excessive exercise, or by a large amount of external pressure being applied, or by a vascular injury.
Severe Swelling, Pain, and Tightness in the Lower Legs
Now, I should point out that acute compartment syndrome is not as common as exertional compartment syndrome, but how do you know if you have one? Well, let’s say you’ve sustained a blow to the shin area. We all know how much this can hurt. With compartment syndrome, the pain will seem all out of proportion to the actual injury. There can be quite severe pain and swelling in the lower leg. The skin may feel tight like it is being stretched and the area may feel very firm. Later on, in severe cases, there may be a pins and needle sensation on the top of the foot and even loss of feeling between the big toe and second toe. Muscle weakness will likely also occur. These symptoms can start occurring within about 30 minutes of the injury.
How Serious is This?
If this starts occurring and does not subside, see a doctor immediately because if left untreated, irreversible damage could occur within 12 to 24 hours. The usual first aid is to immobilize the ankle and ice application. Do not use compression! Remember, pressure is the problem. You don’t want to produce more. Also, do not elevate the limb as this only decreases the arterial pressure so decreasing the blood supply to the tissues. If the symptoms do not subside pretty quickly or they get progressively worse, see a doctor because it is likely that the pressure will need to be surgically released.
Exertional Compartment Syndrome
We’ve talked about acute compartment syndrome, so you may have guessed that this other kind, exertional compartment syndrome is a chronic type. That’s right. And it is sometimes called chronic compartment syndrome or chronic exertional compartment syndrome, or recurrent exertional compartment syndrome.
Exertional means that it occurs during exercise or activity. This type of pressure is intermittent and it only occurs during exercise, to subside after you stop exercising. There are actually four compartments of the leg. By the way, something I forgot to mention: Before I said that compartment syndrome occurs in the lower leg to avoid confusion. Professionals will usually just call this the leg, instead of the lower leg. The ‘upper’ leg is called the thigh. Okay, so the four compartments of the leg are the anterior, or front, the lateral, or side, and the superficial and deep posterior, which are the back part of the leg, superficial meaning closer to the skin and deep being underneath this compartment. The compartments that are most frequently affected are the anterior compartment, and the deep posterior compartment, the latter occurring about 20 to 30% of cases. The lateral compartment can sometimes also be affected.
Exercise-Induced Aching and Cramping or Burning in the Lower Leg
I mentioned before that acute compartment syndrome can sometimes be caused by excessive exercise. This would usually only be the case for sedentary people who suddenly start exercising strenuously. That’s not likely to happen to a well-conditioned athlete. On the other hand, exertional compartment syndrome is actually more common in well-conditioned athletes that are younger than 40 years. What are the symptoms? There will be an exercise-induced aching or cramping leg pain. This is sometimes described as a burning pain, as well. There may also be a sense of fullness or heaviness, in the involved compartment. This will tend to occur at a predictable time in the exercise session when a certain intensity has been reached. It will then slowly subside after the exercise is stopped, although there may be some residual discomfort. There is swelling in the leg when this occurs. In fact, the girth of the leg may measurably increase. Also, there may be tenderness to touch, which is likely to occur at a certain point at about the mid-third of the tibia, although this may not occur. This is likely to happen bilaterally, meaning in both legs.
Numbness and Tingling
Numbness or tingling may also occur in the leg. Often, the athlete notices a numbness in the dorsal surface of the web space between the big toe and second toe, similar to what I mentioned in acute compartment syndrome. Sometimes, the first symptom is a spreading numbness in the plantar surface of the foot, which is the bottom or sole of the foot. This condition often happens in runners or jumpers. It may even happen to swimmers. A runner may notice also that foot slapping starts to occur as the muscle function declines. A general weakness of the leg may be experienced.
Recurrent exertional compartment syndrome more often occurs in athletes with heavier builds and it seems to be more likely in female athletes. As the exercise continues, the symptoms will progressively worsen. The symptoms usually stop within 30 minutes after exercise ends. It is possible for the symptoms, after a while, to start to linger even after the exercise is stopped, for up to two days. Many different factors can be related to this, such as exercise patterns, footwear, running or training surface, etc., but the exact etiology of the condition is unknown.
If you stop exercising completely, the symptoms will go away, but they will usually come back as soon as you begin again. Exertional compartment syndrome, if you think you have it, is not something you should treat like shin splints. If you have these symptoms, you should see a doctor. In fact, many people will tell you that if you have shin splints that don’t get better with at home care, you should see a doctor. Often, they are talking about compartment syndrome. If you need to know more about this, consult a professional. This article is meant to give you a basic understanding, not to replace medical advice.