In Vitro Wear Testing of a CoCr-UHMWPE Finger Prosthesis with Hydroxyapatite Coated CoCr Stems

摘要: Abstract: A finger prosthesis consisting of a Cobalt-chromium (CoCr) proximal component and an Ultra-high-molecular-weight-polyethylene (UHMWPE) medial (both mounted on hydroxyapatite coated stems) was evaluated to 5,000,000 cycles in vitro simulator. One “test” cycled through flexion-extension (90°–30°) with dynamic load 10 N, whilst immersed lubricant dilute bovine serum. Additionally, static 100 N applied for 45 s every 3000 simulate gripping force. second “control” the same account absorption. Gravimetric Sa (3D roughness) measurements were taken at 1,000,000 cycle intervals. Micrographs values revealed negligible change CoCr surfaces after cycles. The UHMWPE also exhibited no distinctive trend, however micrographs indicate that polishing occurred. Both test components progressively decreased weight. control did not weight, gained weight To disparity between surface gravimetric results, coatings examined. stems coating partially removed, uniform coating.