This is an open access book. In honor of his 75th birthday, we reflect on the impact of the pioneering work of Alan Grodzinsky and his laboratory. This volume includes in-depth discussions of tissue electromechanics, mechanobiology and biomechanics, and matrix biology in addition to the latest advancements in understanding the pathogenesis, progression and treatment of osteoarthritis. Unique to this volume, we overview decades of groundbreaking research that set the stage for the latest efforts in the field, highlighting the legacy of one researcher and their trainees.

Osteoarthritis (OA), the most common form of arthritis, is generally characterized by a slowly progressive degeneration of articular cartilage, particularly in the weight-bearing joints. It has a stronger prevalence in women, and its incidence increases with age. OA is a major and growing health concern in developed countries, owing to steadily increasing life expectancy and the demand for better quality of life. Because of its chronic nature and nonfatal outcome, OA affects the growing population of the elderly over an increasing time span. Moreover, despite its relatively benign character, OA is one of the most disabling diseases; it is responsible for increasing financial and social burdens in terms of medical treatments, forced inactivity, loss of mobility, and dependence. Despite a growing awareness of OA as a medical problem that has yet to reach its maximum impact on society, there is a surprising absence of effective medical treatments beyond pain control and surgery. So far, only symptom-modifying drugs are available, while there remains a major demand for disease-modifying treatments of proven clinical efficacy. This demand will hopefully be met in the future by some of the drugs that have been pressed into development and are now at different stages of clinical investigation. Nevertheless, the current lack of effective treatments reflects a still insufficient knowledge of cartilage with respect to its metabolism, interactions with other joint tissues, and causes and mechanisms (possibly of very different nature) leading to failure of its turnover.

Well-known for their inability to heal, articular cartilage injuries often degenerate inexorably to disastrous impairment. Multitudes of treatments have been devised for this problem, but no satisfactory long-term solutions have been established. Written by world-class experts, Articular Cartilage covers the latest research and advancements related to biology, development, pathology, clinical applications, and tissue engineering. This book is useful for rheumatologists, orthopaedic surgeons, cartilage biologists, and cartilage engineers as well as for professionals working in the orthopaedic and other musculoskeletal industries. This book also belongs in the library of primary care physicians, gerontologists, physical therapists, kinesiologists, and chiropractors. Written at a level that allows accessibility to a wide audience, it provides an interdisciplinary approach that encompasses the breadth and depth of basic science, bioengineering, translational science, and detailed methodologic approaches. The authors examine the major events and signaling molecules that lead to development of articular cartilage from precursor cells, and the changes in cartilage as it matures and ages. They focus on the epidemiology, etiopathogenesis, and therapeutic approaches for cartilage injury and the major arthritides that affect cartilage and the synovial joints such as osteoarthritis, rheumatoid arthritis, and gout. They supply an up-to-date overview of the field of tissue engineering as applied to articular cartilage repair. They examine a number of methods used to assess structure, composition, biology, and biomechanical function. Each chapter contains extensive references to enhance additional study. The book’s comprehensive focus on multiple aspects of articular cartilage sets it apart from other tissue engineering or developmental biology-based books available. It includes important discussions and perspectives on many of the remaining challenges and opportunities in the development and translation of new approaches for treating diseases of articular cartilage. It also provides detailed working protocols for many of the methods used to study articular cartilage, coverage of current treatment options, and business and regulatory aspects of the development of cartilage products. It provides a deeper understanding that will help with the development of new products and clinical applications.

Over recent years, there has been increasing interest in the fundamental role played by local mechanical parameters in chondrocyte regulation and cartilage dysfunction as a first step in the development of osteoarthritis. This is how the idea of mechanobiology and the concept of mechanotransduction were born in the 90's. Indeed, a broad diversity of physiological phenomena is induced by mechanical stimuli (hearing, orientation to gravity, touch, tissue remodeling...) but the mechanism by which mechanical forces may regulate a physiological response is still unknown. In other respects, the concept of regenerative medicine has recently developed in parallel to this. Regenerative medicine is an emerging multidisciplinary field involving medicine, biology, chemistry, mechanics and engineering that is likely to revolutionize the ways we improve the health and quality of life by restoring, maintaining or enhancing tissue and organ functions. Indeed, human tissues do not regenerate spontaneously and healing is only a stopgap that may be associated with contraction which in turn may prevent regeneration. interesting alternative. Today, the in vitro preparation of biological tissues such as cartilage, bone, tendon, vessel, heart muscle, skin, brings out major expectations for the next decade. However, to each type of tissue correspond a large number of potential methods related to the support, the cells used (tissular cells or stem cells) and to the conditions of the environment (culture medium and mechanical forces). The aim of this publication is to provide a thoughtful and balanced view on new crucial concepts with clinical implications.

Cartilage injuries in children and adolescents are increasingly observed, with roughly 20% of knee injuries in adolescents requiring surgery. In the US alone, costs of osteoarthritis (OA) are in excess of $65 billion per year (both medical costs and lost wages). Comorbidities are common with OA and are also costly to manage. Articular cartilage's low friction and high capacity to bear load makes it critical in the movement of one bone against another, and its lack of a sustained natural healing response has necessitated a plethora of therapies. Tissue engineering is an emerging technology at the threshold of translation to clinical use. Replacement cartilage can be constructed in the laboratory to recapitulate the functional requirements of native tissues. This book outlines the biomechanical and biochemical characteristics of articular cartilage in both normal and pathological states, through development and aging. It also provides a historical perspective of past and current cartilage treatments and previous tissue engineering efforts. Methods and standards for evaluating the function of engineered tissues are discussed, and current cartilage products are presented with an analysis on the United States Food and Drug Administration regulatory pathways that products must follow to market. This book was written to serve as a reference for researchers seeking to learn about articular cartilage, for undergraduate and graduate level courses, and as a compendium of articular cartilage tissue engineering design criteria. Table of Contents: Hyaline Articular Cartilage / Cartilage Aging and Pathology / In Vitro / Bioreactors / Future Directions

The molecular and cellular approaches to the relationship of joint and bone problems distinguish this from other books on the topic. Advances in bone and joint biology enable practitioners to approach clinical problems more comprehensively. Emphasis on genetics and on newer viewpoints and approaches, exemplified by the possible effect of subchondral bone on osteoarthritis, gives a wider viewpoint to the reader and may enable novel approaches to solving a clinical problem.