What can cause compartment syndrome?

Compartment syndrome occurs when there is an increase in pressure within a confined space of the body, typically in muscle compartments. This increased pressure can lead to decreased blood flow, tissue ischemia, and eventually necrosis if not addressed promptly. The primary mechanism for developing compartment syndrome is the buildup of contents within the compartment, which directly elevates internal pressure.

Increased compartment contents can include swelling from trauma, bleeding into the compartment, or the presence of excessive muscle mass (such as after intense exercise). As the pressure rises beyond the threshold that can maintain adequate blood flow, the surrounding structures, including nerves and blood vessels, become compressed, leading to a clinical emergency that requires intervention.

Decreased blood flow to the limb can be a result of compartment syndrome rather than a cause. Fractures of the wrist can contribute to the development of compartment syndrome if they lead to swelling or bleeding in the compartments of the forearm but are not the direct cause in other contexts. Increased joint mobility does not relate to the development of compartment syndrome, as it does not affect the pressure dynamics within a compartment. Therefore, the most accurate answer pertains to the increase of contents within a compartment.