title: Wear degradation of long-term in vivo exposed alumina-on-alumina hip joints: linking nanometer-scale phenomena to macroscopic joint design.
abstract: The wear behavior of alumina femoral heads was examined at follow-up periods between 7.7 and 10.7 years. Four head retrievals of the same size (28 mm in diameter) were divided into two groups with different design characteristics. Systematically using scanning electron and atomic force microscopy procedures, wear characteristics could be classified on the entire heads according to five zones with increasing degrees of wear damage (Grade 1-5), in addition to one zone of stripe wear (Grade SW). The stripe wear zone showed quite different topographical features as compared to frictionally worn zones. Furthermore, hip implants designed with different clearances are shown to lead to different wear patterns on the femoral head surface, the smaller the clearance the wider the worn surface area. Cathodoluminescence piezo-spectroscopy provided information about the residual stress state in surfaces worn to different degrees and helped clarifying the wear mechanisms on the microscopic scale.
authors: Ceramic Physics Laboratory and Research Institute for Nanoscience, Kyoto Institute of Technology, Sakyo-ku, Matsugasaki, Kyoto, Japan.
authors: Yasuhito
authors: Y
authors: Takahashi
authors: Nobuhiko
authors: N
authors: Sugano
authors: Wenliang
authors: W
authors: Zhu
authors: Takashi
authors: T
authors: Nishii
authors: Takashi
authors: T
authors: Sakai
authors: Masaki
authors: M
authors: Takao
authors: Giuseppe
authors: G
authors: Pezzotti
mesh_terms: D000368:Aged; D000537:Aluminum Oxide / Q000737:chemistry*; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D017276:Friction; D006621:Hip Joint / Q000473:pathology*; D006622:Hip Prosthesis; D006801:Humans; D049449:Luminescence; D008297:Male; D008422:Materials Testing; D018625:Microscopy, Atomic Force / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008875:Middle Aged; D015233:Models, Statistical; D011474:Prosthesis Design; D011475:Prosthesis Failure; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D000537:Aluminum Oxide