Pain management in total knee arthroplasty: efficacy of a multimodal opiate-free protocol

Abstract

Purpose: this study was conducted to identify the most effective method of postoperative pain management, comparing the intravenous opiate infusion protocol with the use of a single periarticular local anesthetic infiltration (LAI) in patients undergoing total knee arthroplasty (TKA) surgery.

Methods: 50 patients submitted to TKA surgery between 2013 and 2015 were divided into two groups. Buprenorphine was administered intravenously to the patients in Group A, while the Group B patients received a single periarticular LAI (ropivacaine and ketorolac) during surgery.

Pain was assessed using a visual analog scale (VAS) and the knee injury and osteoarthritis outcome score. Hemoglobin and hematocrit were measured in the early postoperative period and at 40 days post-surgery. Range of motion and inflammatory markers were also assessed. Statistical analysis was performed using Student’s t-test.

Results: student’s t-test showed no significant difference between the groups in functional outcomes or blood values, but a difference in VAS score on the day of surgery was found (p < 0.0001), in favor of Group B.

Conclusions: LAI considerably reduces postoperative pain, allowing rapid mobilization and accelerating functional recovery.

Level of evidence: Level I, prospective single-blind randomized trial.

Key Words

arthroplasty - knee - local anesthetic infiltration - opiate - pain management