Periarticular multimodal drug injection is better than single anesthetic drug in controlling pain after total knee arthroplasty

Background Postoperative pain is one of the issues that concern most patients after total knee arthroplasty (TKA). Periarticular multimodal drug injection and single anesthetic agent injection have been shown to effectively reduce postoperative pain. The purpose of this study was to compare the efficacy between multimodal drug injection and single anesthetic drug injection in controlling pain after TKA using a double-blinded randomized controlled trial. Methods Sixty-four osteoarthritic patients who underwent primary TKA were randomized into two groups. The multimodal drug injection group (group M) received levobupivacaine 150 mg, ketorolac 30 mg and morphine 5 mg, while the single anesthetic drug injection group (group S) received only levobupivacaine 150 mg. The primary outcomes were pain level (VAS), quantity of opioid consumption (mg) and time to request the first dose of analgesic drug (min). Results Multimodal drug injection provided lower pain level in the first 4 h after surgery (VAS rest: 30 vs 46, p = 0.02; VAS motion: 45 vs 66, p = 0.03). They consumed less morphine mostly in the first 8 h after surgery (5 vs 12 mg, p