Related Experiment Video
Updated: Oct 21, 2026
Knee Arthrocentesis in Adults
Published on: February 25, 2022
Perineural or intravenous dexamethasone for adductor canal and iPACK blocks in total knee arthroplasty: A randomised
Tomasz Reysner1, Alicja Bartkowska-Śniatkowska1,2, Jowita Rosada-Kurasińska1
1Poznan University of Medical Sciences, Department of Pediatric Anesthesiology and Intensive Care, Poznan, Poland.
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.
