title: Preservation of the posterior cruciate ligament is not helpful in highly conforming mobile-bearing total knee arthroplasty: a randomized controlled study.
abstract: OBJECTIVE
  The purpose of this study is to investigate whether the preservation of the posterior cruciate ligament (PCL) can be helpful for improving kinematics and clinical outcome in highly conforming mobile-bearing total knee arthroplasty (TKA).
  
  
  METHODS
  Ninety osteoarthritic knees were randomly allocated to either the PCL-preserving group or the PCL-sacrificing group. Passive kinematics was recorded with a navigation system immediately after implantation. Three parameters (anterior/posterior translation, varus/valgus rotation, and internal/external rotation) were analysed from 0° to 120° flexion.
  
  
  RESULTS
  The PCL-preserving group (42 knees) had more varus rotation over 90° flexion (p < 0.05) and more anterior translation of the femur in all ranges of flexion (p < 0.05) than those in the PCL-sacrificing group (44 knees). There was no difference in the internal/external rotation (p > 0.05). The range of motion, functional scores, and radiographic results did not significantly differ between the two groups at the final follow-up. Three knees in the PCL-preserving group were revised: two presented with instability caused by traumatic attenuation of the PCL and one with subluxation of the insert due to a tight PCL.
  
  
  CONCLUSIONS
  The preservation of the PCL was not helpful for improving kinematics and clinical outcome in highly conforming mobile-bearing TKA.
authors.affiliation: Department of Orthopedic Surgery, Seoul National University Hospital, 101 Daehak-Ro Jongno-Gu, Seoul, 110-744, Korea, nohbody7@gmail.com.
authors.forename: Yoon Whan
authors.initials: YW
authors.lastname: Roh
authors.forename: Jak
authors.initials: J
authors.lastname: Jang
authors.forename: Won Chul
authors.initials: WC
authors.lastname: Choi
authors.forename: Joon Kyu
authors.initials: JK
authors.lastname: Lee
authors.forename: Sae Hyung
authors.initials: SH
authors.lastname: Chun
authors.forename: Sahnghoon
authors.initials: S
authors.lastname: Lee
authors.forename: Sang Cheol
authors.initials: SC
authors.lastname: Seong
authors.forename: Myung Chul
authors.initials: MC
authors.lastname: Lee
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D016119:Posterior Cruciate Ligament / Q000601:surgery*; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology; D020127:Recovery of Function; D012086:Reoperation; D012399:Rotation; D016896:Treatment Outcome