Femoral nerve block--the anatomical basis for a single injection technique.

A technique for blocking the femoral nerve using a single needle placement is described. It depends on an appreciation of the anatomy and the need to feel loss of resistance twice as two fascial layers are penetrated during insertion of the needle just lateral to the femoral artery. A single injection of bupivacaine 0.35-0.5 per cent of at least 0.3 ml/kg will produce a satisfactory block.