Background and aims Reconstruction of the anterior cruciate ligament (ACLR) is associated with a moderate degree of postoperative pain. The aim of the study is to assess the analgesic efficacy of intravenous (IV) ibuprofen compared with IV ketoprofen for the postoperative pain in adults.

Methods After Ethics Committee approval, a total of 50 patients scheduled for ACLR under spinal anesthesia were randomly assigned in 1:1 ratio to receive 600 mg IV-ibuprofen or IV 100 mg ketoprofen at the skin closure. The following doses were administered at 12 hours for the first 24 hours postoperatively. All patients received the same postoperative multimodal analgesia protocol. At 24 hours postoperatively were recorded the cumulative morphine to maintain a numerical pain scale value of 3 or less, the duration of analgesia from initiation the spinal anaesthesia until the first analgesic requirement and the number of patients with side effects.

Results Demographic data and surgical technique were similar between groups. Perioperative administration of IV-Ibuprofen 600 mg every 12 hours in ACLR patients was safe and decreases morphine requirements and pain score similar with ketoprofen, without side effects.

Conclusions We consider appropriate the use of IV ibuprofen in a multimodal analgesia protocol for postoperative pain at patients with ACLR. In our study, IV ibuprofen was safe and well tolerated.