 Hypothesis 2: When inserting a perineural catheter for a continuous peripheral nerve block, the use of electrical stimulation, as compared with ultrasound-guidance, is associated with increased sensory deficit the day following moderate-to-severely painful orthopedic surgery as measured with a simple 0-10 scale 0no numbness; 10completely insensate of the part of the foot with the greatest sensory deficit at the time of the data-collection phone call. 