Time of block performance starts from first palpation of landmarks to the final injection of local anesthetics. The site of needle insertion was identified and marked (Surgical Skin Marker VX100; Vio Healthcare, Hailsham, East Sussex, UK) as the groove between the biceps femoris and vastus lateralis muscle 10 cm above the top of the patella. (4) A 22G 80mm (SonoPlex Stim Cannula Pajunk Medizintechnologie Germany) insulated needle is inserted with a nerve stimulator set at 1.0mA. The needle is inserted perpendicular to the skin and redirected at a 30 degree angle relative to the horizontal plane. The needle depth is estimated using the midpoint of the thigh and the tangential trajectory of 30 degrees. If plantar flexion is elicited, the nerve stimulator is dialed down to produce a stimulation at 0.4mA or less. If stimulation persists at 0.2mA, the needle is withdrawn until stimulation disappears at 0.2mA but persists below 0.4mA. If dorsiflexion is elicited, the needle is inserted deeper to achieve plantarflexion. Internal rotation of the leg may be help in achieving the angulation.(4) If the needle does not achieve any stimulation, the needle is redirected in 5 degree increments between a 15 to 45 degree trajectory. (5) When the needle is in the correct position, 20 cc of 1.5% mepivacaine is injected in 5 cc increments over 30 seconds. Aspiration for blood is performed before injection and after every 5 cc of injection. Injection is stopped if blood is aspirated or if there is pain on injection. The needle is then repositioned or the block abandoned on the discretion of the anesthesiologist doing the block. However, blood aspiration or pain will be noted.