Compartment syndrome is defined as an increased intracompartmental pressure within inelastic fascia which surround muscular compartments. That pathology can be either acute or chronic. The acute situation is generally a medical emergency. Unless a fasciotomy is rapidly performed, increasing pressure may completely cut off blood flow and cause necrosis of the affected limb. The chronic compartment syndrome, more frequent, is characterized by exercise-induced pain and swelling that is relieved by rest. It results from an excessive intra-muscular pressure increase. The anterior compartment of the leg is most commonly involved. To accurately diagnose the compartment syndrome, physicians perform measurements of compartment pressure. By means of miniature digital instruments, exercise and rest intramuscular pressure are recorded. If pressures reach the critical threshold (30 mm Hg) and remain high five minutes after exercise, compartment syndrome is present. Treatment is nearly exclusively surgical. It consists in an fasciotomy allowing a complete recovery and a return to sport activities.