Arthroscopic techniques for the fixation of a three-dimensional scaffold for autologous chondrocyte transplantation: structural properties in an in vitro model.

PURPOSE: The aim of the present study was to evaluate the structural properties of matrix-associated autologous chondrocyte implantation with multiple fixation techniques implanted in fresh porcine knees after they had undergone load to failure. METHODS: We evaluated the ultimate failure load, yield load, and stiffness of 3 different techniques for the fixation of a 2-mm thick polymer fleece: (1) fixation with biodegradable polylevolactide pins, (2) a transosseous anchoring technique, and (3) conventional suture fixation. Techniques 1 (pin) and 2 (transosseous anchoring) can be used arthroscopically. RESULTS: Maximum load and yield load were significantly higher in the group 1 (pin fixation) and group 2 (transosseous anchoring) compared to group 3 (conventional suture). Stiffness was significantly higher in group 1 than in groups 2 or 3. CONCLUSIONS: Our biomechanical data show that two fixation techniques (pin fixation and transosseous anchoring) have a higher ultimate load, yield load, and stiffness than the conventional suture technique at time point zero. However, these data can be interpreted only with the Bioceed-C matrix (BioTissue Technologies GmbH, Freiburg, Germany). CLINICAL RELEVANCE: Our biomechanical data show outstanding fixation strength with arthroscopic techniques that use Bioceed-C matrix scaffolds during autologous chondrocyte transplantation. Thus, arthroscopic fixation done with this biomaterial should benefit patients, which, in turn, should lead to further research on these arthroscopic techniques and this biomaterial.