641 patients undergoing total hip arthroplasty were randomized to one of six study medication arms for the purpose of comparing postoperative pain relief experienced at rest and during movement when taking either dexketoprofen/tramadol (25mg/75mg) or dexketoprofen 25mg or tramadol 100 mg alone, during both a singular- and a multiple-dose phase. Results demonstrated that patients who received the combination medication (dexketoprofen/tramadol) had significantly improved mean sum of pain intensity differences (SPID) throughout the first 8 hours after the primary dose when compared to patients who received singular components (monotherapy). Other pain outcomes measured during the multi-dose phase generally confirmed a greater reduction in pain with dexketoprofen/tramadol compared to monotherapy when study groups were combined.