title: Bipolar fresh osteochondral allograft of the ankle.
abstract: BACKGROUND
  Severe post-traumatic ankle arthritis poses a reconstructive challenge in the young and active patient. Bipolar fresh osteochondral allograft (BFOA) may represent an intriguing alternative to arthrodesis and prosthetic replacement. The aim of this study was to describe a lateral trans-malleolar technique for BFOA, and to evaluate the results in a case series.
  
  
  METHODS
  From 2004 to 2006, 32 patients, mean age of 36.8 +/- 8.4 years, affected by ankle arthritis underwent BFOA with a mean followup of 31.2 months. The graft was prepared by specifically designed jigs, including the talus and the tibia with the medial malleolus. The host surfaces were prepared by the same jigs through a lateral approach. The graft was placed and fixed with twist-off screws. Patients were evaluated clinically and radiographically at 2, 4, and 6 month after operation, and at a minimum 24 months followup. A biopsy of the grafted areas was obtained from 7 patients at 1-year followup for histological and immunohistochemical examination.
  
  
  RESULTS
  Preoperative AOFAS score was 33.1 +/- 10.9 and postoperatively 69.5 +/- 19.4 (p < 0.0005). Six failures occurred. Cartilage harvests showed hyaline-like histology with a normal collagen component but low proteoglycan presence and a disorganized structure. Samples were positive for MMP-1, MMP-13 and Capsase-3.
  
  
  CONCLUSIONS
  The use of BFOA represents an intriguing alternative to arthrodesis or arthroplasty. We believe precise allograft sizing, stable fitting and fixation and delayed weightbearing were key factors for a successful outcome. Further research regarding the immunological behavior of transplanted cartilage is needed.
authors.affiliation: VI Divisione di Ortopedia e Traumatologia, Istituti Ortopedici Rizzoli, University of Bologna, Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: Giannini
authors.forename: Roberto
authors.initials: R
authors.lastname: Buda
authors.forename: Brunella
authors.initials: B
authors.lastname: Grigolo
authors.forename: Roberto
authors.initials: R
authors.lastname: Bevoni
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Caprio
authors.forename: Alberto
authors.initials: A
authors.lastname: Ruffilli
authors.forename: Marco
authors.initials: M
authors.lastname: Cavallo
authors.forename: Giovanna
authors.initials: G
authors.lastname: Desando
authors.forename: Francesca
authors.initials: F
authors.lastname: Vannini
mesh_terms: D000328:Adult; D000842:Ankle / Q000503:physiopathology / Q000601:surgery*; D001168:Arthritis / Q000503:physiopathology / Q000601:surgery; D001706:Biopsy; D001860:Bone Plates; D001863:Bone Screws; D002356:Cartilage / Q000378:metabolism / Q000473:pathology / Q000637:transplantation*; D053148:Caspase 3 / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D007431:Intraoperative Complications; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D011183:Postoperative Complications; D012189:Retrospective Studies; D014184:Transplantation, Homologous
chemical_list: C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II; D053148:Caspase 3; D053509:Matrix Metalloproteinase 13; D020781:Matrix Metalloproteinase 1