Periarticular Injection of Liposomal Bupivacaine Offers No Benefit Over Standard Bupivacaine in Total Knee Arthroplasty: A Prospective, Randomized, Controlled Trial.

Background: Periarticular injection of liposomal bupivacaine has been adopted as part of multimodal pain management after total knee arthroplasty (TKA).

Methods: In this prospective, randomized clinical trial, we enrolled 162 patients undergoing primary TKA in a single institution between January 2014 and May 2015. Eighty-seven patients were randomized to liposomal bupivacaine (experimental group), and 75 patients were randomized to free bupivacaine (control group). All patients received spinal anesthesia and otherwise identical surgical approaches, pain management, and rehabilitation protocols. Outcomes evaluated include the patient-reported visual analog pain scores, narcotic consumption, and narcotic-related side effects (Brief Pain Inventory) within 96 hours after surgery as well as functional outcomes using the Knee Society Score and the Short-Form 12 measured preoperatively and at 4-6 weeks after surgery.

Results: There were no statistically significant differences between the groups in terms of postoperative daily pain scores, narcotic consumption (by-day and overall), or narcotic-related side effects. There were no statistically significant differences between the groups in terms of surgical (P = .76) and medical complications or length of hospital stay (P = .35). There were no statistically significant differences in satisfaction between the groups (P = .56) or between the groups in postoperative Knee Society Score (P = .53) and the Short-Form 12 at 4-6 weeks (P = .82, P = .66).

Conclusion: As part of multimodal pain management protocol, periarticular injection of liposomal bupivacaine compared with bupivacaine HCl did not result in any clinically or statistically significant improvement of the measured outcomes following TKA.