It is inconclusive whether the perioperative administration of systemic lidocaine provides effective postoperative analgesia and enhances recovery in major orthopaedic surgery. We hypothesised that in adolescent and adult patients undergoing posterior spinal arthrodesis, a perioperative lidocaine infusion would reduce opioid requirements during the first 24 postoperative h. 70 patients undergoing posterior arthrodesis were enrolled in this prospective, randomised, double-blind, placebo-controlled clinical trial. Patients received total i.v. anaesthesia with propofol and remifentanil and were randomized to an adjuvant therapy with either lidocaine i.v.-bolus injection of 1.5 mg kg−1 at induction of anaesthesia, followed by an infusion of 1.5 mg kg−1 h−1 which was continued until six h after arrival at the post-anaesthesia care unit or placebo (equal volumes of saline). Postoperative pain was treated with patient-controlled i.v. morphine. Primary endpoints of this study were morphine requirements in the first postoperative 24 h. Systemic lidocaine did not decrease morphine requirements in the first 24 postoperative h lidocaine-group: 48 (23) mg (mean(sd)) vs placebo-group: 51(19) mg, P = 0.22. Likewise, groups were not different with respect to the severity of postoperative pain, morphine consumption after 48 and 72 h, incidence of postoperative nausea and vomiting, perioperative inflammation, time to recovery of intestinal function, hospital length of stay, and quality of life (assessed preoperatively and one month postoperatively using the SF-12 physical and mental composite scores). In our study, systemic lidocaine had no analgesic benefits in posterior arthrodesis when added to an opioid-based anaesthetic regimen. Eudra CT 2012-005264-98.