Joint homeostasis in tissue engineering for cartilage repair

Abstract

Traumatic joint damage, articular cartilage and the research into methods of restoring the articulation are not new topics of interest. For centuries, clinicians have recognized the importance of cartilage damage and sought ways of learning about the normal form and function of hyaline cartilage as well as the process of degradation and restoration. Unfortunately, only some of the real problems have been solved partially, while a lot of basic knowledge has been available for centuries. More recently, tissue engineering was introduced as a method of restoring tissue or organ function, and has already been applied to cartilage repair. The possibility of modulating cells and tissues and applying this novel capability towards the restoration of musculoskeletal function provides great promise and opportunity for progress in orthopedics and traumatology. Currently, various strategies have been introduced for tissue engineering in cartilage repair, but so far no solid foundation for full clinical implementation has been established. Therefore, the general aim of this thesis is to investigate influences on cartilage tissue engineering and to identify areas where the outcome can be improved. Given the history of the field of musculoskeletal research, it is important to realize the relativity of individual contributions and the constraints on real progress of scientific knowledge in time. No clearer can this be illustrated than by offering the reader insight in the historically available knowledge. As early as in old Egyptian civilization, descriptions of cartilage as a tissue and the relevance of articular degradation as a disease have been found. Scholars such as Aristoteles, Hippocrates and Leonardo da Vinci already contributed to these investigations, but were also the first to suggest that If one way be better than another, that you may be sure is Nature s way (Aristotle, 4th century B.C.) and Human ingenuity makes inventions but none as beautiful, simple or to more purpose than Nature (Leonardo da Vinci, 15th century). One of the first literature contributions on cartilage biology by the British surgeon William Hunter is a historic hallmark paper, which demonstrates the value and bright practical insight of (almost) forgotten knowledge, and provides the reader of this thesis with a solid grasp of what is important to orthopedic surgeons who perform their research in the field of cartilage repair and surgical intervention. Hunter s description of cartilage biology, though not as detailed as our current knowledge, is accurate, relevant and clear. The clinical problem colorfully described by Hunter remains largely unsolved, although we have fortunately progressed beyond the point at which our patients submit unhappily to extirpation, a doubtful remedy, or wear out a painful though probably short life .