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. 2020 Apr;99(17):e19918.
doi: 10.1097/MD.0000000000019918.

Continuous versus single shot adductor canal block for postoperative pain relief after total knee arthroplasty: A protocol for randomized controlled trial

Yulin Tao  1 , Qingjun Mao  2 , Jixiang Wang  3
Affiliations

Continuous versus single shot adductor canal block for postoperative pain relief after total knee arthroplasty: A protocol for randomized controlled trial

Yulin Tao et al. Medicine (Baltimore). 2020 Apr.

Expression of concern in

  • Expression of Concern: Study Protocols.
    [No authors listed] [No authors listed] Medicine (Baltimore). 2025 Nov 7;104(45):e46330. doi: 10.1097/MD.0000000000046330. Medicine (Baltimore). 2025. PMID: 41204616 Free PMC article. No abstract available.

Abstract

Background: Adductor canal block has become a popular mode of pain management after total knee arthroplasty. This study compared a single-injection adductor canal block (SACB) with continuous adductor canal block (CACB). The hypothesis was that the 2 groups would have equivalent analgesia at 48 hours post-neural blockade.

Methods: This is a double-blinded, randomized, controlled, equivalency trial that is conducted at a single university hospital in China. A total of 60 patients who meet inclusion criteria are randomized in a ratio of 1:1 to either CACB (0.5% ropivacaine 20 mL followed by continuous infusion of 0.2% ropivacaine at 5 mL/h for 48 hours) or SACB (0.5% ropivacaine 20 mL) group. The primary outcome is pain scores at 48 hours utilizing the visual analog scale, whereas the secondary outcomes include opioid consumption, Timed Up & Go test, ambulation distances at discharge, length of stay, and maximal flexion at discharge. All pain scores are assessed by an independent observer who is blinded to the allocation of groups.

Results: This study has limited inclusion and exclusion criteria and a well-controlled intervention. This clinical trial is expected to provide evidence of better therapy for the pain management after total knee arthroplasty.

Trial registration: This study protocol was registered in Research Registry (researchregistry5431).

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Conflict of interest statement

The authors have no conflicts of interests to disclose.

Figures

Figure 1
Figure 1
Flow diagram of the study.
See this image and copyright information in PMC

References

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