Study intervention
Patients were randomly allocated in a 1:1:1 ratio to 1 of 3 study arms and received either 2×250 ml solutions of 75 mg diclofenac combined with 30 mg of orphenadrine, 2×250 ml solutions of 75 mg diclofenac or 2×250 ml solutions of isotonic saline in a double-blind setting. Randomization of the study patients in a 1:1:1 randomization ratio took place presurgery, using the web-based randomizer provided by the Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz (Graz, Austria, Flowchart of the study protocol. 