Perineural or intravenous dexamethasone for adductor canal and iPACK blocks in total knee arthroplasty: A randomised trial
In brief
Perineural dexamethasone delays rescue opioids to 18.5 hours after knee replacement
In a 90-patient randomized trial, perineural dexamethasone extended the median time to first rescue opioid to 18.5 hours, versus 13.9 hours with intravenous dexamethasone and 4.5 hours with placebo. At 48 hours, 37% of patients given perineural dexamethasone remained opioid-free; no nerve injury or motor weakness occurred, but larger studies are needed to assess safety.
- Journal
- Pain medicine (Malden, Mass.) (Q1)
- Published
- 19 October 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- Tomasz Reysner, Alicja Bartkowska-Śniatkowska, Jowita Rosada-Kurasińska, Katarzyna Wieczorowska-Tobis, Przemysław Daroszewski, Malgorzata Reysner
- PMID
- 42895857
- DOI
- 10.1093/pm/pnag140
Why clinicians should know about it
- Picked for Orthopedics and Sports Medicine (paper of the day, 21 October 2026): RCT of dexamethasone adjuncts for TKA blocks
Abstract
INTRODUCTION: Total knee arthroplasty causes substantial postoperative pain. Combined adductor canal and interspace block between the popliteal artery and posterior knee capsule (iPACK) provides motor-sparing analgesia, but its duration is limited. We compared perineural and intravenous dexamethasone as adjuncts to these blocks in older patients undergoing primary total knee arthroplasty. METHODS: In this prospective, randomised, quadruple-blind, parallel-group trial, 90 patients aged 65-100 years were allocated equally to receive adductor canal and iPACK blocks with ropivacaine plus perineural dexamethasone 4 mg in total (2 mg per block), intravenous dexamethasone 4 mg, or placebo. The primary outcome was time to first rescue opioid analgesia within 48 h. Secondary outcomes included opioid consumption, pain scores, inflammatory markers, blood glucose, quadriceps strength, and neurological safety. RESULTS: Time to first rescue opioid analgesia differed between groups (log-rank p < 0.001). Median time (95% CI) was 4.5 (4.5-5.5) h with placebo, 13.9 (12.5-14.7) h with intravenous dexamethasone, and 18.5 (16.5 to not reached) h with perineural dexamethasone. The proportions remaining opioid-free at 48 h were 0%, 23.3%, and 36.7%, respectively. Opioid consumption and pain scores were lower with both dexamethasone routes than with placebo; perineural administration resulted in the lowest opioid consumption and lower pain scores than intravenous administration at later timepoints. Perineural dexamethasone was associated with lower postoperative neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios, whereas intravenous dexamethasone was associated with higher blood glucose. No motor weakness or nerve injury occurred. DISCUSSION: Perineural dexamethasone prolonged analgesia and reduced opioid requirements more than intravenous dexamethasone, without neurological or motor impairment. The inflammatory-marker findings were exploratory and do not establish independent clinical benefit.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.