This case report details the feasibility of a continuous lumbar plexus block obtained with a paramedian transverse scan of the lumbar paravertebral region, using a catheter-over-needle system, as a main postoperative orthopedic analgesia, in a 14-month-old patient undergoing surgical treatment of a localized Ewing family tumor of the right proximal femur. After surgery, the patient remained in the intensive care unit for 3 days; pain was assessed regularly using the Children's and Infants' Postoperative Pain Scale, and comfort was monitored. Analgesia was provided with continuous levobupivacaine 0.2% infusion 0.2 mL kg h, rectal paracetamol 15 mg kg, and oral ibuprofen 60 mg twice per day, with a dose of morphine 0.05 mg kg intravenously as rescue. Pain relief was excellent, and no additional morphine was needed during the postoperative course. Nausea, vomiting, and disturbed sleep were not reported. Oral diet was resumed on the first postoperative day. In conclusion, this case represents successful postoperative management of orthopedic pain in a child using continuous posterior lumbar plexus infusion.