Background: Total knee arthroplasty (TKA) results in significant postoperative pain and a demanding postoperative path for recovery. This study was conducted to determine whether a femoral nerve block (FNB) or a periarticular injection of liposomal bupivacaine with an adductor canal block (LB+ACB) is superior for pain management.
Materials and methods: A total of 557 consecutive primary TKA cases performed at a single hospital between 2010-2014 were retrospectively reviewed. After enrollment criteria were met, 390 cases remained (FNB=181, LB+ACB=209). Inpatient and post-discharge variables related to pain, narcotic use, healthcare resource utilization, and cost were compared.
Results: There were no significant differences in demographics between the two groups. There was also no significant difference in inpatient postoperative pain between the two groups. The FNB group consumed fewer narcotics overall compared to the LB+ACB group (p<0.001). However, the LB+ACB group experienced fewer opioid-related adverse events (p<0.001). The LB+ACB group had a shorter length of stay (p<.001), fewer readmissions (p=0.017) and reoperations (p=0.025), and lower costs (p<0.001).
Discussion: LB+ACB proved to be an equally effective postoperative TKA pain management tool compared to FNB while displaying superiority in other increasingly important areas such as length of stay and cost. The larger amount of narcotic consumption is a concern, however, and there may be a small population of patients for whom LB+ACB is not the best option.