Thick layers of tissue, called fascia, separate groups of muscles in the arms and legs from each other. Inside each layer of fascia is a confined space, called a compartment. The compartment includes the muscle tissue, nerves, and blood vessels. Fascia surrounds these structures, similar to the way in which insulation covers wires.

Fascia do not expand. Any swelling in a compartment will lead to increased pressure in that area. This raised pressure, presses the muscles, blood vessels, and nerves. If this pressure is high enough, blood flow to the compartment will be blocked. This can lead to permanent injury to the muscle and nerves. If the pressure lasts long enough, the muscles may die and the arm or leg will no longer work. Surgery or even amputation may be done to correct the problem.

Acute compartment syndrome may be caused by:

Trauma, such as a crush injury or surgery

Broken bone

Very bruised muscle

Severe sprain

A cast or bandage that is too tight

Loss of blood supply due to the use of a tourniquet or positioning during surgery



Long-term (chronic) compartment syndrome can be caused by repetitive activities, such as running. The pressure in a compartment only increases during that activity and goes down after the activity is stopped. This condition is usually less limiting and does not lead to loss of function or limb. However, the pain can limit activity and endurance.

Compartment syndrome is most common in the lower leg and forearm. It can also occur in the hand, foot, thigh, buttocks, and upper arm.