[The bovine cartilage punch model: a tool for the in vitro analysis of biomaterials and cartilage regeneration].

BACKGROUND

The limited regeneration capacity of hyaline articular cartilage requires detailed studies concerning the tissue integration of cartilage transplants with meaningful but time and/or resource-consuming and in part ethically problematic animal models or, alternatively, with in vitro test systems for implant materials.

MATERIAL AND METHODS

The present study describes a regeneration model with bovine cartilage rings (outer Ø 6 mm, central defect Ø 2 mm) for insertion, cultivation and biomechanical or histological testing of cartilage replacement materials (HE and safranin O staining). In this study, resorbable polymers composed of polyglycolic acid (PGA) were analyzed.

RESULTS

Biomechanical testing showed a continuous decrease of the push-out force for the PGA inserts from the cartilage rings, probably due to the resorbability of the material. Histologically, clear immigration of cells into cell-free PGA was observed even after 4 weeks of culture, but in particular after 10 weeks. In addition, storage of proteoglycans was interpreted as an initial sign of the formation of new matrix.

CONCLUSION

Thus, the new regeneration model is in principle suitable for the testing of biomaterials, but shows limitations in assessing the "lateral bonding" of resorbable materials.