Interscalene nerve blocks (ISB) are commonly used for perioperative analgesia after shoulder arthroscopy, including arthroscopic rotator cuff repair (RCR). Historically, bupivacaine has been the primary local anesthetic for ISBs. In 2018 the FDA approved liposomal bupivacaine for use in ISBs. This trial was designed to compare ISBs performed with bupivacaine alone (B) versus a combination of liposomal bupivacaine plus bupivacaine (LBB) to determine effects on postoperative pain control and opioid consumption following RCR.
This was a prospective, single-center, double-blinded, randomized controlled trial conducted between January 2020 and April 2024 and reported following CONSORT guidelines. A total of 128 opioid-naive patients scheduled for arthroscopic RCR were randomized 1:1 to receive either:
Randomization, blinding procedures, and adherence to protocol were described in the study methods as part of a level I randomized controlled trial. The ClinicalTrials.gov registration number reported was NCT06139666.
Collected variables included patient demographics, comorbidities, any additional procedures performed at the time of RCR, daily opioid consumption converted to morphine milligram equivalents (MME), and daily visual analog scale (VAS) pain scores for the first 14 postoperative days. Data capture focused on early postoperative analgesia and total opioid exposure over two weeks.
The two randomized groups did not differ significantly in age, sex, comorbidities, or American Society of Anesthesiologists (ASA) physical status classification. This balance supports comparability for reported outcomes.
Daily MMEs were compared between groups across the 14-day postoperative period. The only statistically significant difference was on postoperative day 2, when the LBB group consumed a lower median MME (reported comparison values: 0.0 [0.0 to 7.5] versus 0.0 [0.0 to 15.0]; P = 0.04). No other individual daily MME differences or differences in total 14-day MME were reported.
The authors emphasize that overall median opioid consumption for the 14-day period was low in both groups. They reported the total median MME as equivalent to a small number of oxycodone tablets (summary reported as approximately 5 [1 to 12] oxycodone pills), underlining limited postoperative opioid requirement in this cohort.
Mean VAS pain scores were recorded daily for 14 days. A statistically lower mean VAS score was observed in the LBB group on postoperative day 2 (4.8 ± 3.0 versus 6.0 ± 2.8; P = 0.03). There were no other statistically significant differences in daily VAS scores over the 14-day follow-up.
The report notes that the VAS difference on POD2 did not meet a minimal clinically important difference threshold, indicating the numeric improvement was unlikely to be clinically meaningful despite statistical significance.
Although the LBB group showed statistically lower opioid consumption and lower VAS scores on postoperative day 2, the magnitude of these benefits was small. The authors interpreted the opioid difference as equivalent to roughly one oxycodone tablet and stated that the VAS improvement did not achieve minimal clinically important difference. There were no sustained reductions in opioid consumption or pain scores across the two-week follow-up, and total opioid exposure remained low in both study arms.
The trial concluded that adding liposomal bupivacaine to bupivacaine for interscalene nerve blocks produced a modest statistical improvement in pain and opioid consumption on postoperative day 2 but that these differences lacked clinical significance. No other differences in pain scores or opioid use were found over the first 14 postoperative days after arthroscopic RCR. The study is reported as Level I evidence and was registered on ClinicalTrials.gov (NCT06139666).
Notes and limitations reported in the abstract
The abstract reports primary outcomes, statistical comparisons on POD2, and overall low opioid consumption across groups. Specifics on adverse events, longer-term outcomes beyond 14 days, protocols for rescue analgesia, or subgroup analyses were not detailed in the abstract and therefore are not reported here.
Copyright and citation
The article is published in the Journal of the American Academy of Orthopaedic Surgeons (J Am Acad Orthop Surg) and the abstract information is reproduced from the PubMed/NCBI record. DOI: 10.5435/JAAOS-D-25-01002.