This Fourth Volume presents the advances and developments in powerful computer technology, computational techniques, and widely diverse areas with significant implications for human betterment that occur continuously at a high rate. These include dynamics of musculo-skeletal systems; mechanics of hard and soft tissues; mechanics of muscle; mechanics of bone remodeling; mechanics of implant-tissue interfaces; cardiovascular and respiratory biomechanics; mechanics of blood flow, air flow, flow-prosthesis interfaces; mechanics of impact; dynamics of man machine interaction; and numerous other areas.