The foot anatomically consists of multiple small compartments. These compartments are filled with muscles, nerves and tendons and are lined by a tight membrane (the fascia). These are anatomically distinct compartments. When injury to the foot occurs, there is commonly some bleeding that occurs in the muscles that causes swelling of the foot. What is often not understood, however, is that when swelling gets severe, the muscle starts to expand.
The lining membrane (the fascia) of each of these small compartments has a limited capacity to expand. If the muscle and fluid swelling inside the compartment become significant, they may exceed the capacity of blood flow in and out of the small compartments. If this occurs, it is called a compartment syndrome. This can be a very serious problem. If the pressure inside the compartment increases too much, the nerves and muscles start to get squeezed and stop functioning properly.
Compartment syndromes of the foot typically occur after fairly significant industrial, agricultural and motor vehicle accidents in which crushing of the foot occurs. There is usually some very heavy object that either runs over the foot, crushes it or impacts on the foot in a significant way. Swelling of the foot begins to occur and is followed by severe pain.
The diagnosis of compartment syndrome is made by inserting a needle into the compartments and measuring the pressure elevation inside each compartment.
Surgical treatment is required to relieve the pressure if it is high. This operation is called a fasciotomy. The presence of compartment syndrome is a medical and surgical emergency and a fasciotomy must be done soon after the injury. Once the cuts are made on the foot (fasciotomy), the pressure is released.
Although the foot stays quite swollen for a while, healing eventually does occur. Commonly, small skin grafts are applied to the incisions to speed up the healing process.