title: No difference in anterior tibial translation with and without posterior cruciate ligament in less invasive total knee replacement.
abstract: OBJECTIVE
  The relative advantages of cruciate retaining or cruciate resecting total knee replacement are still controversial. If the posterior cruciate ligament (PCL) is preserved, it should be properly balanced. In a previous study, it was demonstrated that increasing the flexion gap leads to an anterior translation of the tibia relative to the femur. Based on these results, we hypothesized that cutting the PCL increases the flexion gap and lessens anterior tibial translation.
  
  
  METHODS
  The amount of anterior tibial translation versus distraction force in the flexion gap was measured in 88 total knee replacements with a less invasive midvastus approach using a custom-made tensioner. Measurements were performed with intact and resected PCL.
  
  
  RESULTS
  The difference in tibial translation with and without PCL is not significant. A 1-mm increase in the flexion gap led to an average anterior translation of 0.6 mm with intact PCL and 0.4 mm with cut PCL, which is less than that reported in a previous study.
  
  
  CONCLUSIONS
  The results have not confirmed our initial hypothesis. The reasons for this may be other soft tissue structures that prevent anterior tibial translation, such as the collateral ligaments, and/or the extensor apparatus. Moreover, the knee flexion angle for the used specific implant may play a role.
  
  
  METHODS
  Prospective comparative study, Level II.
authors.affiliation: Department of Orthopaedic Surgery, Salem Spital, Bern, Schänzlistrasse 39, 3000, Bern 25, Switzerland. bernhard.christen@ortho-klinik.ch
authors.forename: Bernhard
authors.initials: B
authors.lastname: Christen
authors.forename: Michal
authors.initials: M
authors.lastname: Neukamp
authors.forename: Emin
authors.initials: E
authors.lastname: Aghayev
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology; D008297:Male; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery; D016119:Posterior Cruciate Ligament / Q000601:surgery*; D013977:Tibia / Q000503:physiopathology*