Liposomal Bupivacaine in Adductor Canal Blocks Before Total Knee Arthroplasty Leads to Improved Postoperative Outcomes: A Randomized Controlled Trial.

Background: This study compares the use of liposomal bupivacaine (Exparel) versus ropivacaine in adductor canal blocks (ACB) before total knee arthroplasties (TKAs).

Methods: From the months of April 2020 to September 2021, 147 patients undergoing unilateral primary TKA were asked to participate in this prospective, double-blinded randomized controlled trial. Each patient received an iPACK block utilizing ropivacaine and was additionally randomized to receive an ACB with Exparel or Ropivacaine. For each patient, demographic information, inpatient hospital information, postoperative opioid use, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire scores were collected.

Results: Overall, 100 patients were included (50 in each cohort). The Exparel group had a lower hospital length of stay compared to the Control group (36.3 vs 49.7 hours, P < .01). Patients in the Exparel group reported an increased amount of Numerical Rating Scale pain score improvement at all postoperative timepoints. These patients also used a lower amount of inpatient opioids (40.9 vs 47.3 MME/d, P = .04) but a similar amount of outpatient opioids (33.4 vs 32.1 MME/d, P = .351). Finally, the Exparel group had increased improvements in all WOMAC subscores and total scores at most timepoints compared to the Control group (P < .05).

Conclusion: Exparel peripheral regional nerve blocks lead to decreases in pain levels, shorter hospital lengths of stay, inpatient opioid usage, and improved WOMAC scores. Exparel can be safely used in ACB blocks before TKA to help in controlling postoperative pain and decrease length of stay.