Tourniquet-induced nerve ischemia complicating knee ligament surgery.

Five patients developed paralysis to the sciatic nerve after the application of a pneumatic tourniquet for knee ligament surgery. Four of these patients made a complete neurologic recovery within 6 months. A subsequent experimental investigation has demonstrated that some degree of impaired function in the sciatic nerve of a dog occurs with every tourniquet application. On the basis of this experimental work, it is recommended that a pneumatic tourniquet not be left inflated for periods longer than 1 hr and 15 min. In addition, it is suggested that once a tourniquet has been deflated during an operative procedure, that it should not be reinflated because of the excessive length of time required for the sciatic nerve conduction velocity to return to normal. Tourniquets should also be checked for calibration before use at time of an operation.