Non-Opioid Analgesia Protocols After Total Hip Arthroplasty and Total Knee Arthroplasty: An Updated Scoping Review and Meta-Analysis

Background: Despite their effectiveness in postoperative analgesia regimens for total knee arthroplasty (TKA) and total hip arthroplasty (THA), opioid medications are accompanied by well-known side effects and a risk of long-term dependence. These drawbacks have prompted the exploration of opioid-free analgesia protocols. The purpose of this study was to summarize the nature and extent of evidence available on opioid-free analgesia protocols in THA and TKA management.

Methods: A scoping review of all Medline, Embase, and CENTRAL-indexed studies published between March 2019 and May 2023 was conducted, focusing on opioid-free analgesia regimens following THA and TKA. All included studies were assessed for potential risk of bias. Meta-analyses of pooled opioid-free percentages and pain scores were conducted using odds ratio and standardized mean difference, respectively, in a random-effects model.

Results: A total of 23 studies (15 TKAs and eight THAs) were included. Among both TKA and THA, rescue opioids were the most commonly reported postoperative intervention. The most commonly investigated nonopioid analgesic modality was local anesthetics/nerve blocks with 52.2% (12 of 23) of the studies, followed by multimodal combinations (21.7%) and intravenous corticosteroids (13.0%). Only two of the 10 included TKA randomized controlled studies demonstrated statistically significant increases in the postoperative opioid-free rates. Of the six included THA randomized controlled trials, four demonstrated statistically significant increases in patients completing the postoperative period opioid-free. Our meta-analysis demonstrated a statistically significant impact of nerve blocks following TKA on the opioid-free rate and postoperative pain scores. Among the included THA studies, all studies in which patients received postoperative intravenous corticosteroids demonstrated significant increases in opioid-free percentage.

Conclusions: Despite some nonopioid analgesics demonstrating promise, rescue opioids remained the most frequently employed postoperative pain medication. The optimized opioid-free analgesic regimen likely requires a multimodal approach, especially using both local anesthetics/nerve blocks and intravenous corticosteroids. Further investigation and reporting of opioid-free episodes of care are needed.