The primary purpose of this study is to determine whether the leg positioning or distal tourniquet used during the injection of local anesthetic may decrease the onset time and prolong the duration of analgesia of ultrasound-guided Sciatic Nerve Block (SNB) with popliteal approach. Patients will be divided randomly into three groups: group 1 will receive sciatic nerve block, with leg kept in a neutral position after anesthesia (control group); group 2 will receive the same anesthesia, with leg raised 30° by placing the back of the foot over a support placed on the OR table and maintained in that position for 15 min; and patients in group 3 will receive the same anesthesia, and distal tourniquet placed on the lower part of the leg (upper part of the tourniquet being about 4-6 inches from the ankle) with the leg in a neutral position