title: No difference in patellar kinematics between fixed-bearing cruciate-retaining and cruciate-substituting total knee arthroplasty: a cadaveric investigation.
abstract: OBJECTIVE
  The influence of cruciate-ligament-retaining (CR-TKA) and cruciate-ligament-substituting (CS-TKA) TKA on tibiofemoral kinematics was analysed in many investigations. However, the influence on patellar kinematics is unclear so far. The aim of this study was to compare patellar kinematics of the natural knee with those after CR- and CS-TKA.
  
  
  METHODS
  Patellar kinematics of nine healthy whole-body cadaveric knees before and after CR- and CS-TKA was investigated using a commercial optical computer navigation system. Patellar kinematics of the healthy knee was compared with those after CR- and CS-TKA.
  
  
  RESULTS
  No significant difference between the natural knee and the knee after TKA or between both types of TKA for patellar kinematics could be found. Interestingly, both types of TKA resulted in a more medial patellar shift and a contrary patellar tilt and rotation behaviour. CR- and CS-TKA resulted in smaller values for patellar epicondylar distance at all flexion angles.
  
  
  CONCLUSIONS
  Our study found no influence of prosthesis type on patellar kinematics. Factors like component alignment and prosthesis design seem to be more important in terms of adequate restoration of patellar kinematics in TKA than whether choosing CR- or CS-TKA.
authors.affiliation: Department of Orthopaedic Surgery, University of Regensburg, Kaiser-Karl-V Allee 3, 93077, Bad Abbach, Germany. keshmiri_armin@yahoo.de.
authors.forename: Armin
authors.initials: A
authors.lastname: Keshmiri
authors.affiliation: Department of Orthopaedic Surgery, University of Regensburg, Kaiser-Karl-V Allee 3, 93077, Bad Abbach, Germany.
authors.forename: Günther
authors.initials: G
authors.lastname: Maderbacher
authors.affiliation: Department of Orthopaedic Surgery, University of Regensburg, Kaiser-Karl-V Allee 3, 93077, Bad Abbach, Germany.
authors.forename: Achim
authors.initials: A
authors.lastname: Benditz
authors.affiliation: Department of Orthopaedic Surgery, Cantonal Hospital Bruderholz, 4101, Bruderholz, Switzerland.
authors.forename: Werner
authors.initials: W
authors.lastname: Müller
authors.affiliation: Department of Orthopaedic Surgery, University of Regensburg, Kaiser-Karl-V Allee 3, 93077, Bad Abbach, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Grifka
authors.affiliation: Department of Orthopaedic Surgery, University of Regensburg, Kaiser-Karl-V Allee 3, 93077, Bad Abbach, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Craiovan
mesh_terms: D000368:Aged; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D001696:Biomechanical Phenomena; D002102:Cadaver; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D007720:Knee Prosthesis; D010329:Patella / Q000503:physiopathology / Q000601:surgery*; D011474:Prosthesis Design; D016059:Range of Motion, Articular
keywords: Computer navigation; Cruciate-ligament-retaining; Cruciate-ligament-substituting; Patellar kinematics; Patellar tracking; Total knee arthroplasty