An animal study on cartilage healing using auricular cartilage as a model.

We investigated the effect of different surgical procedures on cartilage healing, using auricular cartilage as a model, which would be useful to create a rationale for septal cartilage surgery. Different kinds of manipulations were performed on the auricular cartilage of six female New Zealand white rabbits. Histopathological investigations were performed under light microscopy 4 months postoperatively. The autologous cartilage grafts survived well under the forehead skin regardless of the presence of the perichondrium. The response of perichondrium to either incomplete or complete trauma was not only new cartilage formation but also ossification. When incomplete incisions were made on the non-perichondrial side, new cartilage formation was stimulated whereas ossification was induced when there was perichondrium on the cartilage. If the cartilage with perichondrium was sliced into small pieces and planted back in its original place, many ossification areas occurred. The crushed cartilage was usually absorbed but sometimes replaced by bony plates. The traumatized cartilage with perichondrium undergoes ossification. This finding may be important clinically in that surgeons should not traumatize septal cartilage with perichondrium and work under the perichondrium. This ossification of traumatized cartilage may later result in thickening of the septal cartilage which we sometimes face in revision surgery.