Arthroscopic three dimensional autologous chondrocyte transplantation with navigation-guided cartilage defect size assessment

The treatment of large full thickness cartilage defects with matrix guided autologous chondrocyte transplantation shows promising results. However, in many cases an arthrotomy is needed to implant the cell seeded scaffolds. Recently techniques have been developed for arthroscopically guided ACT implantation. Correct defect mapping, to assess size and depth of the chondral lesions, and precise scaffold preparation and fixation are crucial for successful chondrocyte transplantation and remain to be not sufficiently optimized. In the present study, the geometries of two cartilage defects in cadaver knees were three times assessed, measured and transferred to biodegradable scaffolds with a navigation system by three different executors. The scaffolds were arthroscopically implanted into the cartilage defects. The cartilage defect assessment was reproducible between all executors for all defect geometries. The implanted scaffolds showed a correct defect filling. The study showed the feasibility of an arthroscopic implantation of scaffolds for autologous chondrocytes transplantation. Navigation was a useful tool to exactly assess the cartilage defect geometry and allowed a precise transfer of navigated cartilage defect geometries for individualized scaffold preparation. Navigation can help to accomplish and optimize arthroscopically guided chondrocyte transplantations.