Diagnosis

Other exercise-related problems are more common than chronic exertional compartment syndrome, so your doctor may first try to rule out other causes — such as shin splints or stress fractures — before moving on to more specialized testing.

Results of physical exams for chronic exertional compartment syndrome are often normal. Your doctor might prefer to examine you after you've exercised to the point of bringing on symptoms. Your doctor may notice a muscle bulge, tenderness or tension in the affected area.

Imaging studies

Imaging studies may include:

• MRI. A typical MRI scan of your legs can be used to evaluate the structure of the muscles in the compartments and rule out other possible causes of your symptoms.

  An advanced MRI scan can help assess the fluid volumes of the compartments. Images are taken at rest, while moving your foot until you feel symptoms, and after the exercise. This type of MRI scan has been found to be accurate in detecting chronic exertional compartment syndrome, and may reduce the need for the invasive compartment pressure testing.

• Near infrared spectroscopy (NIRS). NIRS is a newer technique that measures the amount of oxygen in your blood in the affected tissue. The test is done at rest and after physical activity. This helps determine if your muscle compartment has decreased blood flow.

Compartment pressure testing

If results from imaging studies do not show a stress fracture or similar cause of pain, your doctor might suggest measuring the pressure within your muscle compartments.

This test, often called compartment pressure measurement, is the gold standard for diagnosing chronic exertional compartment syndrome. The test involves the insertion of a needle or catheter into your muscle before and after exercise to make the measurements.

Because it's invasive and mildly painful, compartment pressure measurement usually isn't performed unless your medical history and other tests strongly suggest you have this condition.