16 patients undergoing open shoulder surgery were randomized to receive either a continuous-infusion brachial plexus block with levobupivacaine or a standard single injection for the management of post-operative pain. Pain scores, consumption of morphine, and motor and sensory block were measured throughout the course of the study. At the end of the 24 hour study period, it was discovered that the continuous-infusion group achieved significantly better sensory and motor blocks, experienced significantly less pain and required significantly less morphine than the single injection group.