Chronic exertional compartment syndrome

Chronic exertional compartment syndrome is an exercise-induced muscle and nerve condition that causes pain, swelling and sometimes disability in the affected muscles of the legs or arms. Anyone can develop the condition, but it's more common in young adult runners and athletes who participate in activities that involve repetitive impact.

Chronic exertional compartment syndrome may respond to nonsurgical treatment and activity modification. If nonsurgical treatment doesn't help, your doctor might recommend surgery. Surgery is successful for many people and might allow you to return to your sport.

Your limbs have specific areas of muscle (compartments). Your lower leg, for example, has four compartments. Chronic exertional compartment syndrome often occurs in the same compartment of an affected limb on both sides of the body, usually the lower leg.

Signs and symptoms can include:

• Aching, burning or cramping pain in a compartment of the affected limb
• Tightness in the affected limb
• Numbness or tingling in the affected limb
• Weakness of the affected limb
• Foot drop, in severe cases, if legs are affected
• Occasionally, swelling or bulging as a result of a muscle hernia

Pain caused by chronic exertional compartment syndrome typically follows this pattern:

• Begins consistently after a certain time, distance or intensity of exertion after you start exercising the affected limb
• Progressively worsens as you exercise
• Becomes less intense or stops completely within 15 minutes of stopping the activity
• Over time, recovery time after exercise may increase

Taking a complete break from exercise or performing only low-impact activity might relieve your symptoms, but relief is usually only temporary. Once you take up running again, for instance, those familiar symptoms usually come back.

If you have recurring unusual pain, swelling, weakness, loss of sensation or soreness while exercising or participating in sports activities, talk to your doctor.

Sometimes chronic exertional compartment syndrome is mistaken for shin splints, a more common cause of leg pain in young people who do a lot of vigorous weight-bearing activity, such as running. If you think you have shin splints and the pain doesn't get better with self-care, talk to your doctor.

The cause of chronic exertional compartment syndrome isn't completely understood. When you exercise, your muscles expand in volume. If you have chronic exertional compartment syndrome, the tissue that encases the affected muscle (fascia) doesn't expand with the muscle, causing pressure and pain in a compartment of the affected limb.

Some experts suggest that how you move while exercising might have a role in causing chronic exertional compartment syndrome. Other causes might include having muscles that enlarge excessively during exercise, having an especially inflexible fascia surrounding the affected muscle compartment or having high pressure within your veins.

Certain factors increase your risk of developing chronic exertional compartment syndrome, including:

• Age. Although people of any age can develop chronic exertional compartment syndrome, the condition is most common in male and female athletes under age 30.
• Type of exercise. Repetitive impact activity — such as running — increases your risk of developing the condition.
• Overtraining. Working out too intensely or too frequently also can raise your risk of chronic exertional compartment syndrome.

Chronic exertional compartment syndrome isn't a life-threatening condition and usually doesn't cause lasting damage if you get appropriate treatment. However, pain, weakness or numbness associated with chronic exertional compartment syndrome may prevent you from continuing to exercise or practice your sport at the same level of intensity.