title: Pain control after total knee arthroplasty: a randomized trial comparing local infiltration anesthesia and continuous femoral block.
abstract: OBJECTIVE
  Pain after total knee arthroplasty (TKA) is usually severe, and epidural analgesia or femoral nerve block has been considered to be an effective pain treatment. Recently, local infiltration analgesia (LIA) has become increasingly popular but the outcome of this method regarding the analgesic effect has not been fully evaluated. We compared local infiltration analgesia and femoral block with regard to analgesia and morphine demand during the first 24 h after TKA.
  
  
  METHODS
  40 patients undergoing TKA under spinal anesthesia were randomized to receive femoral nerve block (group F) or peri- and intraarticular infiltration analgesia (group LIA) with a mixture containing ropivacaine, ketorolac, and epinephrine. All patients had access to intravenous patient-controlled analgesia (PCA) with morphine postoperatively. Pain intensity at rest and upon movement was assessed on a numeric rating scale (0-10) on an hourly basis over 24 h if the patients were awake.
  
  
  RESULTS
  The average pain at rest was marginally lower with LIA (1.6) than with femoral block (2.2). Total morphine consumption per kg was similar between the 2 groups. Ancillary analysis revealed that 1 of 20 patients in the LIA group reported a pain intensity of > 7 upon movement, as compared to 7 out of 19 in the femoral block group (p = 0.04).
  
  
  CONCLUSIONS
  Both LIA and femoral block provide good analgesia after TKA. LIA may be considered to be superior to femoral block since it is cheaper and easier to perform.
authors.affiliation: Department of Anesthesiology and Intensive Care, Section of Orthopaedics, Karolinska Institute and Karolinska University Hospital, Solna, Sweden.
authors.forename: Fatin
authors.initials: F
authors.lastname: Affas
authors.forename: Eva-Britt
authors.initials: EB
authors.lastname: Nygårds
authors.forename: Carl-Olav
authors.initials: CO
authors.lastname: Stiller
authors.forename: Per
authors.initials: P
authors.lastname: Wretenberg
authors.forename: Christina
authors.initials: C
authors.lastname: Olofsson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000577:Amides / Q000008:administration & dosage; D000698:Analgesia / Q000379:methods*; D000772:Anesthesia, Local / Q000379:methods; D000779:Anesthetics, Local / Q000008:administration & dosage; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods; D016861:Cyclooxygenase Inhibitors / Q000008:administration & dosage; D004837:Epinephrine / Q000008:administration & dosage; D005260:Female; D005267:Femoral Nerve; D006801:Humans; D020910:Ketorolac / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy / Q000517:prevention & control / Q000628:therapy*; D000077212:Ropivacaine; D016896:Treatment Outcome
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D016861:Cyclooxygenase Inhibitors; D000077212:Ropivacaine; D004837:Epinephrine; D020910:Ketorolac