title: Does Patient Perception Differ Following Adductor Canal Block and Femoral Nerve Block in Total Knee Arthroplasty? A Simultaneous Bilateral Randomized Study.
abstract: Femoral nerve block (FNB) has been used as part of the multimodal analgesia after total knee arthroplasty (TKA), but leads to weakness in the quadriceps muscles. Recently, adductor canal block (ACB) was reported to provide effective pain relief while sparing the strength of the quadriceps. This simultaneous bilateral randomized study investigated whether patients perceived differences between ACB and the FNB after same-day bilateral TKA.
  
  
  
  We performed a prospective simultaneous bilateral randomized study in 50 patients scheduled to undergo same-day bilateral TKA. One knee was randomly assigned to ACB and the other knee was assigned to FNB. All ACB and FNB were performed using ultrasound-guided single-shot procedures. These 2 groups were compared for pain visual analogue scale, straight leg raising ability and knee extension while sitting, and motor grade. At postoperative week 1, the peak torque for the quadriceps muscle was measured in both knees with an isokinetic dynamometer.
  
  
  
  There were no differences in pain levels between ACB and FNB during the entire study period. During the first 48 h after TKA, more of the knees that received ACB could perform straight leg raising and knee extension with greater quadriceps strength compared with FNB. However, no group differences in quadriceps functional recovery were found after postoperative 48 h and isometric quadriceps strength at postoperative 1 week.
  
  
  
  This simultaneous bilateral randomized study demonstrates that patients did not perceive differences in pain level, but experienced substantial differences in quadriceps strength recovery between knees during the first 48 h (Identifier: NCT02513082).
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul St. Mary's Hospital, Seoul, Korea; Department of Anesthesia and Pain Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Hyun J
authors.initials: HJ
authors.lastname: Koh
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, Seoul, Korea; Department of Orthopaedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: In J
authors.initials: IJ
authors.lastname: Koh
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, Seoul, Korea.
authors.forename: Man S
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, Seoul, Korea.
authors.forename: Keun Y
authors.initials: KY
authors.lastname: Choi
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul St. Mary's Hospital, Seoul, Korea.
authors.forename: Hyeon U
authors.initials: HU
authors.lastname: Jo
authors.affiliation: Department of Orthopaedic Surgery, Seoul St. Mary's Hospital, Seoul, Korea; Department of Orthopaedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Yong
authors.initials: Y
authors.lastname: In
mesh_terms: D000368:Aged; D000698:Analgesia / Q000379:methods; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D005267:Femoral Nerve; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D009407:Nerve Block / Q000379:methods*; D059408:Pain Management / Q000379:methods; D010147:Pain Measurement; D058748:Pain Perception; D010149:Postoperative Pain / Q000517:prevention & control*; D011446:Prospective Studies; D052097:Quadriceps Muscle / Q000502:physiology*; D020127:Recovery of Function; D013848:Thigh
keywords: adductor canal block; femoral nerve block; multimodal pain management; peripheral nerve block; same-day bilateral total knee arthroplasty