title: The role of lamellate phospholipid bilayers in lubrication of joints.
abstract: This study aims to determine the effect of progressive loss of the surface active phospholipids on the characteristics, and hence tribological function of articular cartilage. In accordance to Hill's hypothesis, 3-7 lipid bilayers at pH 7.4 operate as the solid lubricant in the cartilage-cartilage interface during physiological function. These bilayers are known to be depleted during cartilage degeneration. This study models this loss of phospholipid bilayers, studying experimentally both wet and dry cartilage surfaces, measuring surface wettability, and friction coefficient under a constant stress of 1.2 MPa. The results demonstrate that the friction coefficient increases gradually with loss of the phospholipid bilayers, and gains in value with decrease in wettability.
authors: Tribochemistry Consulting, Salt Lake City, UT 84117, USA. zpawlak@xmission.com
authors: Zenon
authors: Z
authors: Pawlak
authors: Wiesław
authors: W
authors: Urbaniak
authors: Adam
authors: A
authors: Gadomski
authors: Kehinde Q
authors: KQ
authors: Yusuf
authors: Isaac O
authors: IO
authors: Afara
authors: Adekunle
authors: A
authors: Oloyede
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000503:physiopathology*; D002417:Cattle; D003198:Computer Simulation; D017276:Friction / Q000502:physiology; D057927:Hydrophobic and Hydrophilic Interactions; D066298:In Vitro Techniques; D008051:Lipid Bilayers / Q000378:metabolism*; D008153:Lubrication; D008954:Models, Biological; D010743:Phospholipids / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology*; D017155:Wettability
chemical_list: D008051:Lipid Bilayers; D010743:Phospholipids