Percutaneous cartilage injection: a prospective animal study on a rabbit model.

Background: Cartilage grafting is a useful technique in nasal reconstruction. Implantation of a whole graft is usually done through an incision. Crushed cartilage can also be used. Injection of cartilage could be an alternative to implantation. The objective of this study is to compare the long-term viability of percutaneously injected crushed auricular cartilage to surgically implanted cartilage in the rabbit.

Methods: Auricular cartilage was harvested bilaterally in 10 New Zealand white rabbits. A 1 cm² cartilage graft was implanted surgically on the upper nasal dorsum. The remaining cartilage was crushed and percutaneously injected on the lower nasal dorsum. Volume and mass of each graft were compared between pre-implantation and after 3 months of observation. A histological study was conducted to evaluate chondrocyte viability and degree of fibrosis on pre and post-implantation cartilage.

Results: Mass and volume remained similar for surgically implanted cartilage grafts. Mass and volume diminished by an average of 47% and 40% respectively after 3 months for the injected crushed cartilage grafts. Chondrocyte viability was an average of 25% lower in the injected grafts.

Conclusions: Cartilage injection is a promising technique that must be refined to increase chondrocyte viability. Developing an appropriate injection apparatus would improve this technique.