Arthritis is a disorder of the joints characterized by joint pain and stiffness. Other symptoms also may arise, such as swelling, redness, decreased range of motion of the affected joints, and warmth. Its onset can be sudden or gradual. Arthritis constitutes of more than 100 different types. Osteoarthritis and rheumatoid arthritis are the most prevalent forms of the condition. Some other types are fibromyalgia, septic arthritis, gout and lupus. The diagnosis of arthritis is based on a clinical examination of the condition with supporting evidence from radiology and blood tests. Various factors need to be evaluated to make an informed diagnosis such as the pattern of joint involvement, speed and time of onset, symmetry of symptoms, gelling or locking with inaction, etc. X-rays of the joints affected can also help to make a diagnosis. Neither rheumatoid arthritis nor osteoarthritis is curable. Depending on the form of arthritis, therapies may be recommended, such as orthopedic bracing, medications, exercise, weight control and physical therapy. In eroding forms of arthritis, joint replacement surgery may be a treatment option. This book covers in detail our current understanding of arthritis and its pathophysiology. Some of the diverse topics covered in this book address the causes, diagnoses and therapies for arthritis. Scientists and students actively engaged in orthopedics will find this book full of crucial and unexplored concepts.