Edelweiss Applied Science and Technology 
ISSN: 2576-8484 

Vol. 2, No. 1, 278-279 
2018 
DOI: 10.33805/2576.8484.154 

© 2018 by the author 

© 2018 by the author 
History: Received: 12 November 2018; Accepted: 19 November 2018; Published: 23 November 2018 

 
 
 
 
 

Opinion Article: Articular Cartilage: Lamellar-Repulsive Lubrication of 
Natural Joints by Zenon Pawlak 

 
Tadeusz Kaldonski 
Department of Tribology, Military University of Technology, Warszawa, Urbanowicza 2, Poland; 
tadeusz.kaldonski@wat.edu.pl (T.K.). 

 
 

Abstract: This monograph attempts to explain a new joint lubrication mechanism with surface active 
phospholipids as a lubricant. It provides studies of the principles of cartilage (smart material) of 
biological micro- and Nano tribology. 
Keywords: Articular cartilage, Natural lubrication, Lamellar-Repulsive mechanism of lubrication of natural joints. 

 
1. Introduction  

The concepts presented in this monograph "lamellar- electrostatic mechanism" are new and 
compatible with the discovery of Prof. Brian Hills’s hypothesis that lamellar phases of PLs and 
phospholipid bilayers are lubricants in natural joints. The concept that boundary lubrication in joints 
was mediated by an active ingredient in Synovial Fluid (SF) was put forward by Jones (1934) , Linn 
and Radin (1968) and Hills (1984). According to Hills and other authors, the Surface Amorphous Layer 
(SAL) of cartilage contains surface-active phospholipids. 

Phosphatidylcholines (over 40%) sphingomyelin (~30%) and phosphatidylethanolamines (~30%) 
were subsequently identified in the synovial fluid and SAL. This book is focused on the mechanism of 
natural lubrication by which the Phospholipids (PLs) in Articular Cartilage (AC) act as a lubricant. The 
physiological function of PLs is unique in preventing solid-solid contact and degradation of the articular 
surface. With AC, it is particularly important to have a model where PLs adsorbed on the surface of 
cartilage impart a number of highly desirable properties. 

The importance of basic properties of the cartilage such as the surface energy, wettability, pH, 
surface charge, and amphoteric surface character were determined and turned out to be compatible with 
some features of joints lubrication. While the principal aim of the book was to provide an understanding 
of the meaning of the surface-active state (lamellar bodies), the other is to highlight the solid PL 
bilayers that possess low surface energy at pH ~7.4, when applied to the body. The understanding 
of AC amphoteric surface will be essential for the effective repair and regeneration of the degraded 
knee joint. In conclusion, it can be stated that the lamellar-electrostatic lubrication mechanism, a 
new approach to understanding natural lubrication, is challenging and deserves to be studied. This 
monograph is intended for advanced undergraduate and graduate medical and biomechanical students 
and researchers in the area of biomechanics and biological systems. 
 
 

mailto:tadeusz.kaldonski@wat.edu.pl


279 

 

 
Edelweiss Applied Science and Technology 

ISSN: 2576-8484 

Vol. 2, No. 1: 278-279, 2018 
DOI: 10.33805/2576.8484.154 
© 2018 by the author 
 

 
Figure 1. 
Cover page. 

 
Abbreviations: SF- Synovial Fluid, SAL- Surface Amorphous Layer, PLs-Phospholipids, AC-Articular 
Cartilage. 
 

References 
[1] Z. Pawlak, Articular Cartilage: Lamellar-repulsive Lubrication of Natural Joins. UKW. Faculty of Matehmatics, Physics 

& Technical Science, 2018. 
 

1.0 Introduction                                                                         1 
2.0 The structure, composition and function of cartilage        5 
2.1 Synovial fluid                                                                        11 
2.2 Phospholipid bilayers as a potential solid lubricant        17 
2.3 Phospholipids                                                                        21 
2.4 Cartilage and antiphospholipid antibody syndrome        25 
3.0 Surface cartilage characteristics                                            35 
3.1 Interfacial energy of PL bilayers                                  39 
3.2 Cartilage surface wettability vs. pH                                  45 
3.3 Friction vs. wettability of cartilage surface                     53 
3.4 Amphoteric cartilage and its consequences                          64 
3.5 Cartilage surface charge density vs. pH                     75 
4.0 Porosity of lubricated cartilage surface                     85 
5.0 The boundary and boundary-layered lubrication        89 
6.0 Lamellar-repulsive mechanism of low friction in Nature    93 
7.0 Resurfacing cartilage surface                                              107 
8.0 Articular cartilage restoration and regeneration       123 
9.0 Summary and outlook                                                         131 
About the Author                                                            137 
Bibliography                                                                         139 

          Index                                                                                    153