We randomized 200 consecutive acute extra-articular tibia fractures into monitored and nonmonitored groups. The monitored group received continuous compartment pressure for 36 hours and the nonmonitored group received usual postoperative observations. In alert patients, the diagnosis of compartment syndrome was made clinically. In unconscious patients, a difference between compartment pressure and diastolic blood pressure (DeltaP) of less than 30 mm Hg was the criteria for fasciotomy