Fig. 1. Mean (± SD) onset times of sensory and motor blocks and readiness to surgery in patients receiving an axillary brachial plexus block with 20 ml ropivacaine, 0.75%, using either ultrasound (group US, n = 30) or nerve stimulation (group NS, n = 29) guidance for nerve location. * P = 0.01 as compared with group NS (Student t test).