Hip replacement, also known as hip arthroplasty, is a surgery in which a prosthetic implant, often known as a hip prosthesis, replaces the hip joint. A whole hip replacement or hemi (half) replacements are two options for hip replacement surgery. Total hip replacement surgery may be prescribed in cases of joint failure caused by osteoarthritis, rheumatoid arthritis, avascular necrosis, traumatic arthritis, protrusio acetabuli, certain hip fractures, benign and malignant bone tumors, etc. Knee replacement or knee arthroplasty, is a surgical method that replaces the weight-bearing surfaces of the knee joint to reduce pain and impairment. This type of surgery is mostly recommended when conservative measures fail to relieve joint discomfort, as well as for other knee disorders such as rheumatoid arthritis and psoriatic arthritis. Infections, blood clot, a fracture during or after surgery, nerve damage, and continued pain or stiffness are some possible complications associated with hip and knee replacement surgery. This book consists of contributions made by international experts. There has been rapid progress in this area of orthopedic surgery. Doctors and students actively engaged in hip and knee arthroplasty will find this book full of crucial and unexplored concepts.