title: Evaluation of a porcine whole-limb heterotopic autotransplantation model.
abstract: BACKGROUND
  Recently performed vascularized composite tissue allotransplantations (CTAs) stimulate the ongoing research in the area of whole-limb transplantation. A reliable in vivo animal model is required for investigations in vascularized whole-limb CTA. The model should allow in vivo assessment in whole-limb preservation, allograft and xenograft response, and host immunomodulation. The goal of this study is to describe and evaluate the in vivo feasibility and reproducibility of a whole-limb porcine model as a basis for future research in this field.
  
  
  METHODS
  In seven large white pigs, one forelimb was amputated under anesthesia and autotransplanted heterotopically with an arc of rotation of 180° and partially placed in a subcutaneous pocket. Clinical parameters were monitored and muscle biopsies were analyzed using ultrastructural morphological assessment of mitochondria quality after an observation period of 7 days.
  
  
  RESULTS
  All animals could fully mobilize postoperatively without restrictions. At sacrifice, the anastomosed pedicle vessels of the limb were patent in six animals. In one pig, venous thrombosis could be observed. Muscle response was triggered following direct electrostimulation in six replanted limbs. The replanted extremities gained 12.97% weight within 7 days postreplantation compared with the amputation baseline values (P = 0.464 while maintaining normal compartment pressures at sacrifice (8.25 ± 5.31 cmH(2)O, P = 0.60). The ultrastructural evaluation of mitochondria morphology revealed intact mitochondria without signs of ischemia/reperfusion damage.
  
  
  CONCLUSIONS
  This porcine model proved feasible, reliable, and reproducible for whole-limb autotransplantation. It presents significant potential in future preclinical research of whole-limb CTA transplantation.
authors.affiliation: Department of Plastic and Hand Surgery, Bern University Hospital, Bern, Switzerland. david.kiermeir@insel.ch
authors.forename: David Manuel
authors.initials: DM
authors.lastname: Kiermeir
authors.forename: Martino
authors.initials: M
authors.lastname: Meoli
authors.forename: Sabine
authors.initials: S
authors.lastname: Müller
authors.forename: Susanne
authors.initials: S
authors.lastname: Abderhalden
authors.forename: Esther
authors.initials: E
authors.lastname: Vögelin
authors.forename: Mihai Adrian
authors.initials: MA
authors.lastname: Constantinescu
mesh_terms: D000671:Amputation, Surgical; D000818:Animals; D004210:Dissection; D005240:Feasibility Studies; D005552:Forelimb / Q000098:blood supply / Q000637:transplantation*; D008866:Microsurgery; D023421:Models, Animal; D015203:Reproducibility of Results; D013552:Swine; D014182:Transplantation, Autologous; D016042:Transplantation, Heterotopic