Effectiveness of Novel Adjuncts in Pain Management Following Total Knee Arthroplasty: A Randomized Clinical Trial.

BACKGROUND: Total knee arthroplasty (TKA) can be associated with significant pain which can negatively impact outcomes. Multiple strategies have been employed to reduce pain. The aim of this study is to compare the effectiveness of 3 different pain management modalities after TKA that included (1) our standardized knee injection cocktail and oral acetaminophen, (2) liposomal bupivacaine periarticular injection and oral acetaminophen, and (3) our standardized knee injection cocktail and intravenous (IV) acetaminophen.

METHODS: A prospective randomized clinical trial was conducted with 3 perioperative pain management regimes: oral acetaminophen and our standardized knee injection cocktail (standard group), oral acetaminophen and liposomal bupivacaine periarticular injection (LB group), and IV acetaminophen and our standardized knee injection cocktail (IVA group). Primary outcome measures included visual analog scale, total morphine equivalents, and the opioid-related symptoms distress scale at 24 and 48 hours postoperatively.

RESULTS: There were no significant differences on visual analog scale/opioid-related symptoms distress scale scores 24 hours after surgery. The LB group required significantly more narcotics (total morphine equivalents) than the standard (P = .025) and IVA groups (P = .032). No significant differences were observed on any of the outcomes measured at 48 hours after surgery.

CONCLUSION: Our data suggest that there is no added benefit in the routine use of IV acetaminophen or liposomal bupivacaine after TKA.