Arthroscopic fixation of matrix-associated autologous chondrocyte implantation: importance of fixation pin angle on joint compression forces.

Purpose: The aim of the study was to investigate the effect of pin fixation perpendicular and 30° tilted to the matrix surface on the joint compression forces.

Methods: In a porcine knee model, joint compression forces were recorded with a digital pressure sensor above the medial meniscus and with axial compression of 100 N by use of a material testing machine. The forces were recorded for an intact femoral condyle, as well as a standardized cartilage defect of 25 × 20 mm, after matrix-associated autologous chondrocyte implantation (m-ACI) (BioSeed C; Biotissue Technologies, Freiburg, Germany), fixed by use of a conventional suture technique and pin fixation with a biodegradable pin perpendicular and 30° tilted to the matrix surface.

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.

Arthroscopic implantation of a three dimensional scaffold for autologous chondrocyte transplantation.

The arthroscopic M-ACT technique is applicable for defects at the femoral condyle up to 5 cm(2). The size of the defect has to be assessed with a specific scaled, percutaneously inserted needle. Then an 8 mm water-stop-cannula is positioned in a suprameniscal portal.