Comparison of Clinically used Bilayer Collagen Membrane and Trilayer Collagen Prototype Fixation Stability in Chondral Defects at the Talus: An Experimental Human Specimen Study

CATEGORY: Basic Sciences/Biologics INTRODUCTION/PURPOSE: The purpose of this human specimen experimental study was to compare the fixation stability of clinically used bilayer collagen membrane with fibrin glue (Chondro-Gide, Geistlich Pharma AG, Wollhusen, Switzerland) with trilayer collagen prototype without fibrin glue in chondral defects at the medial or lateral talar shoulder. METHODS: Eleven human specimens were used. The membranes were implanted in standardized chondral defects at the medial and lateral talar shoulder (randomized). All tests were performed in load-control (15kg). Range of motion (ROM) of each ankle was examined individually before testing. The average ROM was 10° dorsalextension (range 0°-20°) and 30° plantarflexion (range 20°-45°). 1,000 testing cycles with the defined ROM were performed. Two independent investigators, blinded to fixation and membrane type, visually assessed the membrane fixation integrity for peripheral detachment, area of defect uncovered, membrane constitution and delamination. RESULTS: The clinically used bilayer collagen membrane plus fibrin glue showed higher fixation stability than the trilayer prototype (all p<0.05). No significant differences occurred between medial and lateral talar shoulder location (all p>0.05). CONCLUSION: The fixation stability of the trilayer collagen prototype without fibrin glue is lower than of the clinically used bilayer membrane with fibrin glue in chondral defects at the medial and lateral talar shoulder in an experimental human specimen test. Clinical use of trilayer collagen prototype without fibrin glue has to be validated by clinical testing to evaluate if the lower stability of fixation is still sufficient.