Compartment Syndrome

Skeletal muscles are grouped inside fascial compartments: enclosed spaces bounded by dense fascia, bone, and connective tissue. Fascia has very little ability to stretch. Bleeding after a fracture, swelling after a crush injury, or pressure from a tight cast can therefore turn the compartment into an overfilled sleeve. As pressure rises, venous outflow is impaired first. Fluid remains in the tissues, swelling increases, and the pressure climbs further. Eventually, the pressure opposing capillary flow becomes high enough that muscle and nerve tissue no longer receive adequate oxygen. Ischemia progresses to necrosis unless the pressure is relieved. Acute limb compartment syndrome is a surgical emergency. It most often affects the lower leg or forearm, but any closed fascial space can be involved.