Rasmussen S, Kramhøft M, Sperling K, Pedersen J. Increased flexion and reduced hospital stay with continuous intraarticular morphine and ropivacaine after primary total knee replacementOpen intervention study of efficacy and safety in 154 patients. ActaO [Internet]. 2004 Jan. 1 [cited 2025 Feb. 23];75(5):606-9. Available from: https://actaorthop.org/actao/article/view/19561