title: Fixation of periprosthetic femur fractures above total knee arthroplasty with the less invasive stabilization system: a midterm follow-up study.
abstract: BACKGROUND
  The complication rate of periprosthetic femoral fractures above well-fixed total knee arthroplasties is high. The Less Invasive Stabilization System (LISS) was introduced to reduce surgical dissections at the fracture site. The purpose of this retrospective study was to evaluate the midterm functional outcome of a group of patients with periprosthetic fractures above well-fixed total knee arthroplasties treated with the LISS.
  
  
  METHODS
  Between January 1999 and June 2004, 23 consecutive patients (all women) with periprosthetic fractures above well-fixed total knee arthroplasties were treated with the LISS. The mean age was 77 years (range, 61-90 years).
  
  
  RESULTS
  Nineteen of the patients (83%) were seen after a midterm follow-up of 46 months (range, 26-67 months). Three patients (13%) died, and one patient (4%) was lost to follow-up. A proximal screw pull-out of the internal fixator occurred in one patient (4%). All fractures healed within a mean of 14 weeks (range, 9-21 weeks). No bone graft was required. There were two delayed unions, no nonunions or infections. One patient (4%) had a malalignment with 7° varus. The mean range of motion was 102° (range, 65-120°). The mean knee score of the Knee Society was 81 points (range, 65-90 points), and the mean function score of the Knee Society was 56 points (range, 35-90 points).
  
  
  CONCLUSIONS
  We found that a minimally invasive, locked plating system permitted stable fixation, early knee motion with good midterm results, and minimal complications. These techniques should be used in place of less stable and more invasive methods.
authors.affiliation: Department of Trauma Surgery, Friedrich-Schiller-University, Jena, Germany. drwerner.kolb@t-online.de
authors.forename: Werner
authors.initials: W
authors.lastname: Kolb
authors.forename: Hanno
authors.initials: H
authors.lastname: Guhlmann
authors.forename: Christoph
authors.initials: C
authors.lastname: Windisch
authors.forename: Frank
authors.initials: F
authors.lastname: Marx
authors.forename: Heiko
authors.initials: H
authors.lastname: Koller
authors.forename: Klaus
authors.initials: K
authors.lastname: Kolb
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods; D001860:Bone Plates / Q000009:adverse effects; D001863:Bone Screws; D005260:Female; D005264:Femoral Fractures / Q000601:surgery*; D005500:Follow-Up Studies; D017102:Fracture Healing; D006801:Humans; D016268:Internal Fixators; D008875:Middle Aged; D057068:Periprosthetic Fractures / Q000601:surgery*; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome