title: Impact of Soft Tissue Imbalance on Knee Flexion Angle After Posterior Stabilized Total Knee Arthroplasty.
abstract: This study was performed to assess the impact of soft tissue imbalance on the knee flexion angle 2 years after posterior stabilized total knee arthroplasty (TKA).
  
  
  
  A total of 329 consecutive varus knees were included to assess the association of knee flexion angle 2 years after TKA with preoperative, intraoperative, and postoperative variables. All intraoperative soft tissue measurements were performed by a single surgeon under spinal anesthesia in a standardized manner including the subvastus approach, reduced patella, and without use of a pneumonic tourniquet.
  
  
  
  Multiple linear regression analysis showed no significant correlations in terms of intraoperative valgus imbalance at 90-degree flexion or the difference in soft tissue tension between 90-degree flexion and 0-degree extension (β = -0.039; 95% confidence interval [CI], -0.88 to 0.80; P = .93 and β = 0.015; 95% CI, -0.29 to 0.32; P = .92, respectively). Preoperative flexion angle was significantly correlated with knee flexion angle 2 years after TKA (β = 0.42; 95% CI, 0.33 to 0.51; P < .0001).
  
  
  
  Avoiding valgus imbalance at 90-degree flexion and aiming for strictly equal soft tissue tension between 90-degree flexion and 0-degree extension had little practical value with regard to knee flexion angle 2 years after posterior stabilized TKA.
authors.affiliation: Department of Orthopaedic Surgery, Nekoyama Miyao Hospital, Niigata, Niigata, Japan.
authors.forename: Sachiyuki
authors.initials: S
authors.lastname: Tsukada
authors.affiliation: Epidemiology and Preventive Services, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan; Japan Society for the Promotion of Science, Kojimachi Business Center Building, Chiyoda, Tokyo, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Department of Orthopaedic Surgery, Nekoyama Miyao Hospital, Niigata, Niigata, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Wakui
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery*; D010329:Patella / Q000601:surgery; D011184:Postoperative Period; D057234:Preoperative Period; D016059:Range of Motion, Articular; D016896:Treatment Outcome
keywords: knee; primary arthroplasty; range of motion; soft tissue balance; tensor device