The purpose of this study is to evaluate the latency period (timing between the injection of the local anesthetic and the onset of complete sensory nerve block) of two approaches for ultrasound-guided popliteal sciatic nerve block: One of the approaches is the injection of the anesthetic just at the site of the bifurcation of the sciatic nerve and the other one is injecting the local anesthetic at least 2 cm beyond the bifurcation of the aforementioned nerve. Our main hypothesis is that the first approach will decrease the latency period, and probably, will increase the success rate of the nerve block as well as patient satisfaction.