Circumferential Spread of Anesthetic and Success in Sciatic Nerve Blockade

Current practices when performing any peripheral nerve block may or may not involve ensuring circumferential spread of local anesthetic around the nerve. Ensuring circumferential spread can involve several redirections of the needle above and below the nerve, and potentially could result in either more discomfort for the patient or an increased chance of inadvertent direct trauma to the nerve. Not ensuring spread around the nerve may result in a slower and less complete blockade. The investigators suspect that by ensuring complete spread around the nerve, the speed of block onset would be quicker because it avoids the loss due to diffusion time.