title: Surgically modifiable factors measured by computer-navigation together with patient-specific factors predict knee society score after total knee arthroplasty.
abstract: BACKGROUND
  The purpose was to investigate whether patient-specific factors (PSF) and surgically modifiable factors (SMF), measured by means of a computer-assisted navigation system, can predict the Knee Society Scores (KSS) after total knee arthroplasty (TKA).
  
  
  METHODS
  Data from 99 patients collected during a randomized clinical trial were used for this secondary data analysis. The KSS scores of the patients were measured preoperatively and at 4-years follow-up. Multiple regression analyses were performed to investigate which combination of variables would be the best to predict the 4-years KSS scores.
  
  
  RESULTS
  When considering SMF alone the combination of four of them significantly predicted the 4-years KSS-F score (p = 0.009), explaining 18 % of its variation. When considering only PSF the combination of age and body weight significantly predicted the 4-years KSS-F (p = 0.008), explaining 11 % of its variation. When considering both groups of predictors simultaneously the combination of three PSF and two SMF significantly predicted the 4-years KSS-F (p = 0.007), explaining 20 % of its variation.
  
  
  CONCLUSIONS
  Younger age, better preoperative KSS-F scores and lower BMI before surgery, a positive tibial component slope and small changes in femoral offset were predictors of better KSS-F scores at 4-years.
authors.affiliation: Research Center of the Department of Orthopedics and Joint Replacement at the Schoen Klinik Hamburg Eilbek, Dehnhaide 120, D-22081, Hamburg, Germany. flampe@schoen-kliniken.de.|Faculty of Life Sciences at the Hamburg University of Applied Sciences, Lohbrügger Kirchstraße 65, D-21033, Hamburg, Germany. flampe@schoen-kliniken.de.
authors.forename: Frank
authors.initials: F
authors.lastname: Lampe
authors.affiliation: Department of Orthopedics and Joint Replacement at the Schoen Klinik Hamburg Eilbek, Dehnhaide 120, D-22081, Hamburg, Germany. ffiedler@schoen-kliniken.de.
authors.forename: Franziska
authors.initials: F
authors.lastname: Fiedler
authors.affiliation: Research Center of the Department of Orthopedics and Joint Replacement at the Schoen Klinik Hamburg Eilbek, Dehnhaide 120, D-22081, Hamburg, Germany. cmarques@schoen-kliniken.de.
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Marques
authors.affiliation: Department of Orthopedics and Joint Replacement at the Schoen Klinik Hamburg Eilbek, Dehnhaide 120, D-22081, Hamburg, Germany. asufi@schoen-kliniken.de.
authors.forename: Anusch
authors.initials: A
authors.lastname: Sufi-Siavach
authors.affiliation: Orthopaedic Department, Jena University Hospital, Campus Eisenberg, Klosterlausnitzer Straße 81, D-07607, Eisenberg, Germany. g.matziolis@krankenhaus-eisenberg.de.
authors.forename: Georg
authors.initials: G
authors.lastname: Matziolis
mesh_terms: D000367:Age Factors; D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000295:instrumentation; D001696:Biomechanical Phenomena; D015992:Body Mass Index; D003661:Decision Support Techniques; D005260:Female; D005858:Germany; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D011237:Predictive Value of Tests; D020127:Recovery of Function; D012307:Risk Factors; D025321:Surgery, Computer-Assisted / Q000009:adverse effects / Q000295:instrumentation; D013997:Time Factors; D016896:Treatment Outcome