Effects of Duloxetine on Pain Relief After Total Knee Arthroplasty in Central Sensitization Patient : A Randomized, Controlled, Double-Blind Trial

This study aims to compare the effectiveness of duloxetine after total knee arthroplasty in Central sensitization patient. Central sensitization plays an important role in the chronic pain experienced by osteoarthritis patients.Elimination of the nociceptive input from the damaged joint by total joint arthroplasty was not always followed by a complete resolution of symptoms. Patients with high levels of preoperative pain and low pain thresholds had a higher risk of persistent pain after total knee arthroplasty (TKA), which has been interpreted as evidence of central sensitization. Thus, the presence of central sensitization before surgery in Osteoarthritis patients may be an important contributing factor to postoperative pain versus adequate analgesia. Preclinical models of central sensitization suggest that duloxetine is effective in the treatment of persistent pain. Investigators will compare the pain following TKA of central sensitization patients in duloxetine group (n=50) with those in non-duloxetine group (n=84). Investigators will classify the central sensitization patients by central sensitization inventory and divide the central sensitization patients in to 2 groups (duloxetine and non-duloxetine group) randomly. Investigators checks the visual assessment scale at preoperative, postoperative 1, 2,6,12 weeks. All participants will receive postoperative pain control after TKA using the same pain control regimen except duloxetine.