title: Intercalary femur allografts are an acceptable alternative after tumor resection.
abstract: BACKGROUND
  With the improved survival for patients with malignant bone tumors, there is a trend to reconstruct defects using biologic techniques. While the use of an intercalary allograft is an option, the procedures are technically demanding and it is unclear whether the complication rates and survival are similar to other approaches.
  
  
  OBJECTIVE
  We evaluated survivorship, complications, and functional scores of patients after receiving intercalary femur segmental allografts.
  
  
  METHODS
  We retrospectively reviewed 83 patients who underwent an intercalary femur segmental allograft reconstruction. We determined allograft survival using the Kaplan-Meier method. We evaluated patient function with the Musculoskeletal Tumor Society scoring system. Minimum followup was 24 months (median, 61 months; range, 24-182 months).
  
  
  RESULTS
  Survivorship was 85% (95% confidence interval: 93%-77%) at 5 years and 76% (95% confidence interval: 89%-63%) at 10 years. Allografts were removed in 15 of the 83 patients: one with infection, one with local recurrence, and 13 with fractures. Of the 166 host-donor junctions, 22 (13%) did not initially heal. Nonunion rate was 19% for diaphyseal junctions and 3% for metaphyseal junctions. We observed an increase in the diaphysis nonunion rate in patients fixed with nails (28%) compared to those fixed with plates (15%). Fracture rate was 17% and related to areas of the allograft not adequately protected with internal fixation. All patients without complications had mainly good or excellent Musculoskeletal Tumor Society functional results.
  
  
  CONCLUSIONS
  Diaphyseal junctions have higher nonunion rates than metaphyseal junctions. The internal fixation should span the entire allograft to avoid the risk of fracture. Our observations suggest segmental allograft of the femur provides an acceptable alternative in reconstructing tumor resections.
  
  
  METHODS
  Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Carlos E. Ottolenghi Institute of Orthopedics, Italian Hospital of Buenos Aires, Potosí 4247, 1199 Buenos Aires, Argentina. luis.aponte@hospitalitaliano.org.ar
authors.forename: Luis
authors.initials: L
authors.lastname: Aponte-Tinao
authors.forename: Germán L
authors.initials: GL
authors.lastname: Farfalli
authors.forename: Lucas E
authors.initials: LE
authors.lastname: Ritacco
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Ayerza
authors.forename: D Luis
authors.initials: DL
authors.lastname: Muscolo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000401:mortality* / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005269:Femur / Q000637:transplantation*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D012516:Osteosarcoma / Q000401:mortality* / Q000601:surgery*; D019736:Prostheses and Implants; D019651:Plastic Surgery Procedures / Q000379:methods*; D012086:Reoperation; D012512:Sarcoma, Ewing / Q000401:mortality* / Q000601:surgery*; D014184:Transplantation, Homologous; D055815:Young Adult