The effects of presence of a backside screw hole on biotribological behavior of phospholipid polymer-grafted crosslinked polyethylene

• Published in: Journal of biomedical materials research. Part B, Applied biomaterials Applied biomaterials, 2018-02, Vol.106 (2), p.610-618
• Main Authors: Watanabe, Kenichi, Moro, Toru, Kyomoto, Masayuki, Saiga, Kenichi, Taketomi, Shuji, Kadono, Yuho, Takatori, Yoshio, Tanaka, Sakae, Ishihara, Kazuhiko
• Format: Article
• Language: English
• Subjects: Acetic Acid - chemistry; Acetic Acid - pharmacology; Artificial joints; Biomedical materials; Bone Screws; Creep strength; Cross-linked polyethylene; Cross-Linking Reagents - chemistry; Cross-Linking Reagents - pharmacology; Deformation; Deformation mechanisms; Deformation resistance; Deformation wear; Disks; Ethylenediamines - chemistry; Ethylenediamines - pharmacology; Finite Element Analysis; Grafting; Gravimetry; Linear Models; Lubricants - chemistry; Lubricants - pharmacology; Materials research; Materials science; Materials Testing; Methacryloyloxyethyl phosphorylcholine; Phospholipids; Phosphorylcholine; Phosphorylcholine - analogs & derivatives; Phosphorylcholine - chemistry; Polyethylene; Polyethylene - chemistry; Polymethacrylic Acids - chemistry; Serum Albumin, Bovine - chemistry; Serum Albumin, Bovine - pharmacology; Sodium Azide - chemistry; Sodium Azide - pharmacology; Surface Properties; Surgical implants; Technology; Ultraviolet Rays; Wear resistance
• ISSN: 1552-4973; 1552-4981
• DOI: 10.1002/jbm.b.33837

One of the important factors in determining the success of joint replacement is the wear performance of polyethylene. Although highly crosslinked polyethylene (CLPE) is presently used, it is still not adequate. We have developed a surface modification technology using poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) in an attempt to improve wear performance. In this study, we evaluated the wear and creep deformation resistances of 3-mm and 6-mm thick PMPC-grafted CLPE disks, set on a metal back-plate, with and without a sham screw hole. The gravimetric wear and volumetric change of the disks were examined using a multidirectional pin-on-disk tester. PMPC grafting decreased the gravimetric wear of CLPE regardless of the presence of a screw hole, and did not affect the volumetric change. The volumetric change in the bearing and backside surfaces of the 3-mm thick disk with a screw hole was much larger than that of those without a screw hole or those of the 6-mm thick disk, which was caused by creep deformation. PMPC grafting on the bearing surface can be a material engineering approach to reduce the wear without changing the creep deformation resistance, and is a promising surface modification technology that can be used to increase the longevity of various artificial joints. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 610-618, 2018.