Sciatic nerve block

The sciatic nerve is located deeply, is complex in its conformation, and is the largest single nerve of the body. Multiple and varied approaches are described for its blockade. It is preferably performed with a peripheral nerve stimulator seeking an adequate muscular response. The block is usually easily and quickly performed, with few complications. It is indicated for pre- or postoperative analgesia either in single dose or with catheter, or for anesthesia of the posterior and inferior regions of the entire leg and foot; in trauma, orthopedics, vascular surgery and radiological procedures, alone or associated with blockades of other nerves. In this review we focused on the relevant anatomic landmarks for each approach and their specific indications. Sciatic blocks have the slowest onset and longest duration compared to other peripheral nerve blocks. In our daily practice, we have adopted the parasacral approach described by Mansour, that allows not only blockade of the major and lesser sciatic nerves but of the obturator nerve as well. It is the most proximal technique of sciatic nerve blockade described and it is in fact a true plexus blockade of the entire sacral plexus. In combination with a femoral blockade, sciatic nerve block gives anesthesia and analgesia to the entire lower extremity unilaterally.