A painful condition caused by too much pressure in the tissue compartments that separate muscle groups.

This condition is caused when pressure in the compartments decreases blood flow. This causes pain and swelling in the affected muscles. Compartment syndrome can be either acute or chronic. Acute compartment syndrome is sudden, serious pain, usually caused by an injury. Chronic, also known as exertional, compartment syndrome is most often caused by exercise.

Chronic compartment syndrome causes pain or cramping when exercising, usually in the lower leg. The pain worsens as you exercise. Pain becomes less intense or stops completely within 15 minutes of stopping activity. Serious, intense pain that gets worse when the muscle is stretched may indicate acute compartment syndrome.

Treatment depends on the type of compartment syndrome. If caused by exercise, rest and conservative measures such as pain relievers and shoe inserts may help. But surgery may be needed. Compartment syndrome caused by sudden, serious injury requires emergency care to save muscles.