Wear on Articulating Cartilage by Titanium Alloy and Cartilage
University of Alberta
Introduction: This project compares the wear present on articulating cartilage on femoral condyles between articulations against titanium alloy disks and native cartilage. As titanium alloy is one of the most common materials used for orthopaedic implants, its effect on articulating cartilage is important to justify its use. Hypothesis: We hypothesize that cartilage on cartilage testing should result in little to no wear whereas titanium alloy on cartilage testing would result in more significant wear. Methods: Femoral condyles with articular cartilage intact was articulated against either titanium alloy disks or the corresponding tibial plateaus with and without the meniscus. A rotation at 3 Hz of +/- 10 degrees and a compressive sinusoidal load between 30 and 160 N at 3 Hz was applied. Testing was done for four hours while immersed in phosphate buffered solution. Wear would be characterized visually and with comparison between pre and post test MRI. Results: Titanium alloy disks resulted in significant wear manifesting as visible areas of wear where cartilage is lost but remained attached to the condyle. As a result, a post-test MRI was not done for these two samples. In contrast, there was relatively little wear observed on both condyles articulating against menisci and one of the condyles articulating against the tibial plateau. No visible wear markings were observed for these samples. One condyle articulating against the tibial plateau had an area of wear like the titanium alloy samples but much less prominent. Conclusion: Titanium alloy specimens resulted in significant wear on the articulating cartilage in comparison to articulation against cartilage and menisci. This is important as it indicates that articular cartilage wear needs to be considered for patients and physicians considering titanium orthopaedic implants.