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Background and Aims Peripheral nerve blocks (PNB), either single shot injection or continuous catheter infusion, are increasingly used in total (hip/knee) joint arthroplasties (TJA). A recent meta-analysis concluded equivalence between single shot and continuous catheter infusion PNBs in immediate perioperative analgesia. However, comparative data on longer term outcomes such as chronic opioid use is scarce. Using national US data we aimed to address this evidence gap.

Methods After institutional review board approval, we utilized US Merative Marketscan commercial claims data (n= 223069 TJAs from 2017-2021). Three groups were compared: 1) no PNB, 2) single shot PNB, and 3) continuous catheter infusion PNB. Risk of chronic opioid use (table 1) was compared between these 3 groups using a multivariable inverse-probability-of-censoring weighting model; we report odds ratios (OR) and 95% confidence intervals (CI).

Results Chronic postoperative opioid use was found in 12.3%, 15.1% and 15.5% of patients without PNB, with single shot PNB, and with continuous catheter, respectively. Our multivariable model showed no difference in chronic opioid use between single shot and continuous catheter PNB use. However, our pairwise comparisons did identify that single shot (versus no) PNB is associated with slightly higher odds of chronic opioid use: OR 1.02 95% CI 1.01-1.03.

Conclusions Our analysis of large data shows no significant difference on chronic postoperative opioid use between single shot and continuous PNB patients. Hereby, we have added to the evidence with more long-term outcomes.