BACKGROUND: Peripheral nerve blocks (PNBs) have the potential to reduce postoperative pain. The use of ultrasound (US) to guide PNBs may be more beneficial than nerve stimulation (NS); however, very few studies have studied this technique in children. The objective of this study was to compare postoperative pain control in pediatric patients who had general anesthesia (GA) alone compared with those who had PNB performed by NS, or PNB with both NS and US guidance. Our hypothesis was that compared with NS, the US-guided PNB would result in reduced postoperative pain and opioid use, and that both PNB conditions would have improved outcomes compared with GA. METHODS: A retrospective chart review of foot and ankle surgery included 103 patients who were stratified into 3 groups: GA, PNB with NS, and PNB with NS and US. Pain levels were measured with visual pain scales at 2, 4, 6, 8, 12, and 24 hours postoperatively. Days of hospitalization, morphine and oxycodone use by weight, and time to first PRN opioid use were also recorded. A repeated measure analysis of variance was used to compare the groups, and the proportion of patients who reported a visual analog scale score of 0 was calculated for each time point. RESULTS: There were no significant differences in pain levels between groups for the first 12 hours, but the US group had higher pain levels at 24 hours. Both US and NS groups had a longer time to PRN opioid use and used significantly less morphine compared with GA. The US group had a significantly greater proportion of pain-free patients than the other 2 groups for the first 6 hours. CONCLUSIONS: The use of US guidance is beneficial in postoperative pain control. Both US-guided and NS-guided PNB are preferable to GA alone for lower extremity orthopaedic surgery in the pediatric population. LEVEL OF EVIDENCE: III, retrospective comparative study.