Compartment syndrome occurs when excessive pressure builds up inside an enclosed space in the body. Compartment syndrome usually results from bleeding or swelling after an injury. The dangerously high pressure in compartment syndrome impedes the flow of blood to and from the affected tissues. It can be an emergency, requiring surgery to prevent permanent injury.
What Happens in Compartment Syndrome?
Groups of organs or muscles are organized into areas called compartments. Strong webs of connective tissue called fascia form the walls of these compartments.
After an injury, blood or edema (fluid resulting from inflammation or injury) may accumulate in the compartment. The tough walls of fascia cannot easily expand, and compartment pressure rises, preventing adequate blood flow to tissues inside the compartment. Severe tissue damage can result, with loss of body function or even death.
The legs, arms, and abdomen are most prone to developing compartment syndrome.
Compartment Syndrome Causes
Acute compartment syndrome is the most common type of compartment syndrome. About three-quarters of the time, acute compartment syndrome is caused by a broken leg or arm. Acute compartment syndrome develops rapidly over hours or days.
Compartment syndrome can develop from the fracture itself, due to pressure from bleeding and edema. Or compartment syndrome may occur later, as a result of treatment for the fracture (such as surgery or casting).
Acute compartment syndrome can also occur after injuries without bone fractures, including:
- Crush injuries
- Overly tight bandaging
- Prolonged compression of a limb during a period of unconsciousness
- Surgery to blood vessels of an arm or leg
- A blood clot in a blood vessel in an arm or leg
- Extremely vigorous exercise, especially eccentric movements (extension under pressure)
Taking anabolic steroids can also contribute to developing compartment syndrome.
Another form of compartment syndrome, called chronic compartment syndrome, develops over days or weeks. Also called exertional compartment syndrome, it may be caused by regular, vigorous exercise. The lower leg, buttock, or thigh is usually involved.
Abdominal compartment syndrome almost always develops after a severe injury, surgery, or during critical illness. Some conditions associated with abdominal compartment syndrome include:
- Trauma, especially when it results in shock
- Abdominal surgery, particularly liver transplant
- Sepsis (an infection causing inflammation throughout the body)
- Severe ascites or abdominal bleeding
- Pelvic fracture
- Vigorous eccentric abdominal exercises (i.e. situps on a back extension machine in weight rooms)
As the pressure in the abdominal compartment rises, blood flow to and from the abdominal organs is reduced. The liver, bowels, kidneys, and other organs may be injured or permanently damaged.