What is Exertional Compartment Syndrome?
Exertional compartment syndrome is a condition that usually happens due to a process of elimination and involves increased pressure in a muscle compartment, leading to insufficient blood supply, commonly felt as pain. Two types of this condition exist; one is the acute type, and the other is the chronic type.
Chronic exertional compartment syndrome (CECS) happens when there are repeated, reversible episodes of decreased blood supply that stop when the activity causing the issue stops, leading to a predictable drop in the pressure inside the muscle compartment. Although CECS isn’t dangerous, it can be persistent, leading many people with the condition to choose to undergo surgery to release the pressure in the affected compartment.
Acute exertional compartment syndrome (AECS) is a less common form of the condition that unfortunately often gets diagnosed late. Similar to acute compartment syndrome (ACS)- a medical emergency requiring immediate surgery to avoid irreversible muscle damage and injury to blood vessels and nerves after a few hours alone, AECS also mean a surgical emergency. ECS usually occurs in the lower leg but can also occur in other parts of the body, including the forearm, thigh, or hand.
This article is an overview of both types of exertional compartment syndrome, emphasizing that clinicians need to be vigilant to avoid delays in diagnosis.
What Causes Exertional Compartment Syndrome?
ECS and ACS are both types of compartment syndrome, but the main difference between the two is that ECS doesn’t involve a specific traumatic event. It’s often missed by doctors, especially the acute subtype, as there isn’t usually a clear cause.
Many factors contribute to CECS. For example, during exercise, certain muscle areas can swell up by 20%. This swelling is due to increased blood flow and fluid volume. In CECS, this leads to a rise in pressure in one or many muscle areas. As the pressure and volume increase, blood flow to the muscles can be compromised, which can cause pain, weakness, or altered sensation in the affected areas. For instance, CECS affecting the front and side of the lower leg may result in pain, a tingling sensation, or reduced feeling on the top of the foot, possibly indicating an issue with the superficial peroneal nerve (SPN).
This abnormal increase in pressure in muscle areas can lead to reduced oxygen supply to muscle cells, ultimately causing damage to muscles and nerves. The symptoms can vary depending on which muscle and/or nerves are affected.
Other causes of CECS include repeated injuries or repeated actions where muscle degradation or scar formation can occur as a result of small-scale injuries. Another risk factor may be a naturally lower elasticity in the muscle covering or fascia, causing a quicker pressure rise that hampers the blood flow of the affected muscle area. Regardless of the exact reason, the condition is usually related to elevated pressure in muscle compartments, typically affecting those involved in repetitive activities such as running, dancing, speed skating, and military training.
Risk Factors and Frequency for Exertional Compartment Syndrome
Chronic exertional compartment syndrome (CECS) is commonly overlooked, but it accounts for 33% of cases in active individuals showing signs of exercise-induced leg pain. This condition is most commonly seen among young athletes who participate in running, endurance training, soccer, field hockey, and lacrosse.
- It usually affects the anterior compartment of the leg (the front portion), accounting for up to 70% of cases. However, the anterior and deep posterior compartments (the front and deep back parts of the leg) are also frequently affected equally.
- In some instances, both these compartments can be affected simultaneously, although this is less common, occurring in 8 to 10% of cases.
- It’s also worth noting that CECS can occur in both legs in anywhere from 37 to 82% of athletes with symptomatic CECS.
- A study of 1411 patients complaining of leg pain found that nearly half, 698 patients, were diagnosed with CECS.
- The condition is most often found in 20 to 25-year-olds, and is slightly more common in males than females.
- Most frequently, it affects those who are active in sports such as running or skating, with a higher likelihood linked to higher intensity activities.
- However, CECS can occur even in patients who are not involved in sports.
Signs and Symptoms of Exertional Compartment Syndrome
It is important to accurately determine if someone has Acute Exertional Compartment Syndrome (AECS) or Chronic Exertional Compartment Syndrome (CECS) as these conditions are often overlooked or diagnosed late. Both are conditions that occur after sports or exertion and result in leg pain. However, while pain from CECS predictably eases off after activity is stopped, AECS may not. It is essential, therefore, to rule out AECS first before other conditions are considered. This can be done by examining the patient’s compartments in question.
The diagnosis of CECS is based on a patient’s detailed medical history with a strong focus on the type and pattern of the pain during strenuous activity. Typically, the discomfort is described as squeezing, cramping, aching or burning starting within 15 to 20 minutes of physical exertion like running. The pain, which is usually found in a specific compartment, tends to disappear quickly once the activity is stopped. In 70 to 95% of the cases, pain is experienced in both legs. However, physical examination results are usually average since the patients are not examined during or immediately after the exercise.
Post-exercise, the affected compartment may feel tight or tender or even bulge. Pain may also be triggered by passive stretching of the compromised compartment. In some cases, there may be focus neurological findings like decreased sensation, numbness, tingling or weakness.
- Physical exercise triggers pain
- Pain eases off when activity is stopped
- Pain is usually in a specific compartment
- Post-exercise, the compartment may be tender, bulge, or feel tight
- Pain is triggered by passive stretching of the compartment
- Neurological findings: decreased sensation, numbness, tingling or weakness
Testing for CECS is performed following exercise and involves measuring compartment pressures before and after exercise using the Stryker pressure monitoring system. Firstly, baseline measurements are taken with the patient resting. The patient then undertakes a period of exercise activity, such as running on a treadmill, in a controlled environment until severe symptoms appear. After resting for 5 minutes, the compartment pressures are measured again. This process allows for effective post-testing.
Testing for Exertional Compartment Syndrome
If your doctor thinks you might have Chronic Exertional Compartment Syndrome (CECS), they’ll rely heavily on your medical history to make a diagnosis as CECS can easily be missed. Once they suspect CECS, they can confirm it by performing a test to measure the pressure inside your muscles both at rest and after exercise.
Your doctor will typically use a guide called the Pedowitz criteria to decide whether CECS is likely. This guide says that CECS may be present if:
- The pressure inside your muscles is 15mmHg or more when you’re at rest, or is 30mmHg or more one minute after you exercise, or;
- The pressure remains at 20mmHg or more five minutes after you’ve stopped exercising.
If your results match these criteria, your doctor can diagnose you with CECS. Otherwise, they might rule out CECS and explore other possible conditions.
Treatment Options for Exertional Compartment Syndrome
If a patient comes to us with an extremely severe condition known as Acute Exertional Compartment Syndrome (AECS), which is a sudden medical emergency, our first course of action would be to immediately perform a surgery called fasciotomies for relief.
But in cases where the condition is Chronic Exertional Compartment Syndrome (CECS), a less severe form of AECS, the preferred mode of treatment is generally non-surgical. The patient is usually managed with this approach for one to three months before considering surgery. The decision to operate is often delayed and it’s only after a detailed discussion about the best timing for the procedure with the patient (or athlete), taking into account their current sport-specific needs, that we proceed.
Non-surgical treatment often includes rest, changing physical activities, stretching, using supportive devices like orthotics, and physical therapy. While these steps are generally not enough, they make up the initial approach to treatment. There are also certain non-surgical treatment options available, such as nonsteroidal anti-inflammatory drugs (NSAIDs) which help lower pain and inflammation, botulinum toxin injections (although they have limited success) and gait training. Gait training involves changing the way you walk or run. There are examples where gait training has shown promising results in some CECS patients, reducing the need for surgery.
However, if these non-surgical options are ineffective after several months, or the condition becomes resistant to treatment, we discuss the possibility of performing surgery, considering patient’s preferences and their expectations to resume their previous levels of physical activity or sports.
The common surgical procedure is an open fasciotomy, but minimally invasive endoscopic techniques are also available which require smaller incisions. However, it’s important to note that both open and minimally invasive surgeries have similar complication rates. For surgeries related to the lower leg, we use two techniques. The first is the ‘dual incision technique’ where incisions are made on the outer side (lateral) and inner side (medial) of the leg to release pressure from different areas, taking care to protect any important nerves.
What else can Exertional Compartment Syndrome be?Chronic Exertional Compartment Syndrome (CECS) is often mistaken for other conditions during an initial diagnosis. It’s commonly misdiagnosed as shin splints or medial tibial stress syndrome.
Other health problems that might be considered during the diagnosis include:
- Vascular issues, such as intermittent claudication or popliteal artery impingement
- Tibial stress fractures
- Tendon problems like tendinitis, tendinosis, or tendon ruptures
- Nerve entrapment
What to expect with Exertional Compartment Syndrome
Patients with isolated anterior (front) and/or lateral (side) compartment involvement, which is over 80% of cases, generally report better results compared to those with deep posterior compartment (back) involvement, which is about 60% of situations.
According to a systematic review of 24 articles by Campano et al., they found a 66% success rate and an 84% satisfaction rate (in the short and mid-term follow-up) after having surgery to repair the condition. Another study by Beck et al. looked back at 155 pediatric patients and showed a 79.5% rate of returning to sports, with 18.8% needing additional surgical revision.
The prognosis, or likely outcome, also depends on the compartment involved, as the front compartment (the most commonly affected location) generally sees better results. Additionally, a single compartment Chronic Exertional Compartment Syndrome (CECS), a condition affecting the legs, has a better surgical success rate than when CECS involves multiple compartments.
Possible Complications When Diagnosed with Exertional Compartment Syndrome
Chronic Exertional Compartment Syndrome (CECS) is mostly harmless and typically goes away when you rest. On the other hand, Acute Exertional Compartment Syndrome (AECS) is much more serious and requires surgical intervention because the symptoms don’t go away on their own. It’s often seen in activities that involve a lot repetition like endurance sports or military training, and usually affects teenagers and young men.[7][31]
Some experts think that this group of people may be more susceptible to AECS due to their muscles developing in a restrictive area.[7][31] Just like with CECS, the pressure in the muscles increases with AECS, but in the case of AECS, it can cause permanent muscle and nerve damage. The ultimate form of treatment is surgery.[7][31]
Unfortunately, as AECS is not a common condition and many people aren’t familiar with it, the diagnosis and treatment often get delayed.[7][31] Being aware of the condition is the first step to diagnosing it. Symptoms are usually intense pain, which is worse when you stretch, and tenderness in the affected area.
To confirm this diagnosis, doctors measure the pressure in the muscles. Normal pressure ranges from 0 to 8mmHg. But if the pressure in the muscles is 30mmHg or more, or if the difference between the diastolic blood pressure and the muscle pressure is less than 30mmHg, then it’s a sign that a surgical procedure called ‘Fasciotomy’ should be performed. If a specific device to measure pressure isn’t available, a standard needle or catheter can be used along with an arterial line monitor.[32]
Symptoms of AECS:
- Persistent symptoms even after rest
- Pain out of proportion
- Pain with passive stretching
- Tenderness in the affected area
Preventing Exertional Compartment Syndrome
Understanding your health is essential. If a certain condition is not easily noticed and often overlooked, it becomes extremely important to educate both healthcare professionals and patients about it. If a patient is experiencing pain in their limbs while exercising that gets better when they rest, it could be a sign of Chronic Exertional Compartment Syndrome (CECS), a condition that affects the muscle compartments in the limbs. It’s crucial to see a doctor in such cases.
Similarly, if someone is experiencing unexplained pain in their limbs, which is significantly severe than what would normally be expected or happens when the affected limb is passively stretched, and the compartments of their muscles become tender, physicians may consider it to be an Acute Exertional Compartment Syndrome (AECS), another condition that affects muscle compartments usually after intense exercising. In such instances, it is important to seek medical attention promptly.
