Background Pain management after total knee arthroplasty is essential to improve early mobilization, rehabilitation, and recovery. Continuous adductor canal (AC) block provides postoperative analgesia while preserving quadriceps strength. However, there have been inconsistencies regarding the optimal location for continuous catheter block. We compared continuous femoral triangle, proximal AC, and distal AC blocks for postoperative analgesia after total knee arthroplasty.
Methods Patients undergoing unilateral total knee arthroplasty were randomly assigned to three groups: femoral triangle, proximal AC, or distal AC. The surgeon performed periarticular local anesthetic infiltration. After surgery, an ultrasound-guided perineural catheter insertion procedure was performed. The primary endpoint was pain scores at rest in the morning on the first postoperative day. Secondary endpoints included pain scores at rest and during activity at other time points, quadriceps strength, and opioid consumption.
Results Ninety-five patients, 32 in the femoral triangle group, 31 in the proximal AC group, and 32 in the distal AC group, completed the study. Analysis of the primary outcome showed no significant difference in pain scores among groups. Secondary outcomes showed significantly lower pain scores at rest and during activity in the distal AC group than in the femoral triangle and proximal AC groups in the morning of the second postoperative day. Quadriceps strength and opioid consumption did not differ among groups.
Conclusions Continuous femoral triangle, proximal AC, and distal AC blocks in the setting of periarticular local anesthetic infiltration provide comparable postoperative analgesia after total knee arthroplasty.
Trial registration number NCT04206150.
- nerve block
- pain, postoperative
- lower extremity
Data availability statement
Data are available upon reasonable request.
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Contributors BL and YSC contributed to study conception and design. BL, SJP, KKP, HJK, YSL, and YSC contributed to study conduct. BL and SJP contributed to data analysis. BL, SJP, KKP, and YSC contributed to manuscript preparation. YSC is a guarantor.
Funding This work was supported by a faculty research grant from the Yonsei University College of Medicine (grant number: 6-2020-0075).
Disclaimer The funder was not involved in the study.
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
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