title: Anterior cruciate ligament reconstruction after unicompartmental knee arthroplasty.
abstract: OBJECTIVE
  ACL deficiency may cause abnormal knee kinematics and is associated with a tenfold increase in surgical failures after unicompartmental knee arthroplasty, such as aseptic loosening of the tibial compartment and medial bearing instability. The current investigators hypothesized that in a knee with UKA, single-bundle ACL reconstruction would restore tibiofemoral translation to levels similar to those of the intact ACL.
  
  
  METHODS
  Two fresh frozen pelvis-to-toes specimens (four paired knees) were used. On each knee, medial unicompartmental knee arthroplasty was performed by a single surgeon. ACL reconstructions were performed by conventional single-bundle technique. Three trials of Lachman and pivot shift tests were performed and recorded for each knee with the ACL-intact, after sectioning the ACL and after single-bundle ACL reconstruction. A mechanized pivot shifter was used to perform the pivot shift maneuvers. A surgical navigation system (Praxim Grenoble, France) simultaneously tracked tibiofemoral kinematics.
  
  
  RESULTS
  There was a significant difference in lateral compartment translation during the Lachman and pivot shift tests between the ACL-intact/UKA knee and the ACL-deficient/UKA knee (P < 0.05). There was no significant difference in lateral compartment translation during the Lachman and pivot shift tests between the intact/UKA knee and the ACL-reconstructed/UKA knee (n.s.).
  
  
  CONCLUSIONS
  For both the Lachman test and the pivot shift test, single-bundle ACL reconstruction restored kinematics in the UKA knee to magnitudes similar to those in the ACL-intact knee.
authors.affiliation: Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, NY 10021, USA. musacitak@gmail.com
authors.forename: Musa
authors.initials: M
authors.lastname: Citak
authors.forename: Marianne Roberta Frederiek
authors.initials: MR
authors.lastname: Bosscher
authors.forename: Mustafa
authors.initials: M
authors.lastname: Citak
authors.forename: Volker
authors.initials: V
authors.lastname: Musahl
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Pearle
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Suero
mesh_terms: D016118:Anterior Cruciate Ligament / Q000503:physiopathology*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods; D001178:Arthroplasty / Q000379:methods*; D001696:Biomechanical Phenomena; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D020370:Osteoarthritis, Knee / Q000601:surgery*; D020127:Recovery of Function