Primary outcome
pain
The duloxetine group had significantly lower pain scores represented by VAS score in the first 48 postoperative hours than the placebo group at all-time intervals: 0–2, 2–4, 4–8, 8–12, 12–24, 24–36 and,36–48, Mean and standard deviation (mean ± SD) (3 ± 0.69) vs. (4.17 ± 0.83), (2.5 ± 0.6) vs. (4.3 ± 0.9), (2.2 ± 0.7) vs. (3.9 ± 0.6), (1.6 ± 0.7) vs. (3.6 ± 0.8), (1.1 ± 0.8) vs.(3.7 ± 0.7), (0.7 ± 0.7) vs. (3.5 ± 0.8), (0.6 ± 0.7) vs. (3.5 ± 0.8) respectively, P value ˂0.01 (Table 
Post-operative VAS score in 48 h, intraoperative fentanyl consumption, and post-operative total morphine consumption in 48 hData were represented as mean, standard deviation, mean difference and 95% confidence interval of the difference