Two patients sustained a severe compartment syndrome of the lower limb after surgery under bloodless field for 1 h 25 min and 43 min and with a tourniquet pressure of 350 and 450 mm Hg, respectively. In both cases fasciotomies were performed as an emergency procedure shortly after the initial operation. Renal failure was avoided but functional deficiencies, peroneal weakness, and restricted movements of the ankle resulted in both cases. We conclude that when using a tourniquet, any pre- and postoperative swelling or stiffness of the muscles in the operation area should be noted, even if the recommended time or pressure limits are not exceeded. Immediate fasciotomies of the affected compartments should be considered if the diagnosis is suspected.