title: Extraarticular knee resection for sarcomas with preservation of the extensor mechanism: surgical technique and review of cases.
abstract: BACKGROUND
  Sarcomas in or contaminating the knee are rare but extremely challenging to treat. Complete resection of the joint is necessary, and often the entire extensor mechanism is removed as well. Reconstruction of the knee is challenging, and the resulting function may be compromised.
  
  
  METHODS
  We describe a surgical technique of extraarticular resection of the knee while preserving the extensor mechanism combined with prosthetic reconstruction. The medial and lateral retinaculum is prepared such that it allows extraarticular placement of K-wires that are driven through the patella and the proximal tibia, serving as in situ guides for the osteotomies.
  
  
  METHODS
  We retrospectively reviewed 11 patients with sarcomas contaminating the knee. The minimum followup was 14 months (mean, 38 months; range, 14-80 months).
  
  
  RESULTS
  At last followup patients had a mean flexion of 88° (range, 65°-120°). We observed no complications related to the extensor mechanism, and there was one local recurrence.
  
  
  CONCLUSIONS
  We believe extraarticular resection of the knee with preservation of the extensor mechanism is a reasonable treatment option for intraarticular sarcomas with functional scores comparable to those for patients having intraarticular resections.
  
  
  METHODS
  Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopaedics, Division of Orthopaedic Oncology, Balgrist University Hospital, University of Zurich, Forchstrasse 340, CH-8008 Zurich, Switzerland.
authors.forename: Pawel
authors.initials: P
authors.lastname: Zwolak
authors.forename: Stefanie P
authors.initials: SP
authors.lastname: Kühnel
authors.forename: Bruno
authors.initials: B
authors.lastname: Fuchs
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D001864:Bone Wires; D002358:Cartilage, Articular / Q000601:surgery; D005260:Female; D005266:Femoral Neoplasms / Q000473:pathology / Q000601:surgery*; D006801:Humans; D007719:Knee Joint / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D019637:Orthopedic Procedures / Q000295:instrumentation; D010027:Osteotomy; D011474:Prosthesis Design; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D012509:Sarcoma / Q000473:pathology / Q000601:surgery*; D013557:Switzerland; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult