Wear on Articulating Cartilage by Titanium Alloy and Cartilage

Student Researcher:
Ruixiang Sun

Supervisor / Principle Investigator:
Nadr Jomha

Additional Authors:
Jonelle Jn Baptiste
Lindsey Westover
Samer Adeeb

MD Class of 2021


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 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 was 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 of full thickness cartilage loss likely by a shearing mechanism with the cartilage remaining 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 the condyles articulating against cartilage with menisci and the condyles articulating against the cartilage without meniscus. Either no visible wear markings were observed or an area of wear similar to the titanium alloy samples but much more superficial were observed.
Conclusion: Titanium alloy specimens resulted in significant wear on the articulating cartilage in comparison to articulation against cartilage with and without meniscus. This is important as it indicates that articular cartilage wear needs to be considered for patients and physicians considering titanium orthopaedic implants directly against cartilage.