Knee extensor mechanism injuries are common injuries and are managed with some degree of immobilisation and restricted weight bearing at some stage to facilitate healing. The aim of this work was to determine the type of immobilisation or splintage and weight bearing status that results in minimal forces acting through the extensor mechanism during stance. This work has important implications for the management of patients with patella and extensor mechanism injuries. The work suggests that lower extensor mechanism forces are seen with lower knee flexion angles. The results also suggest that improvements in knee brace design to allow 0 degrees of knee flexion, rather than the 9 or 10 degrees commonly obtained, are likely to result in significantly reduced extensor mechanism tensile forces. This book will be useful not only for Orthopaedic Surgeons managing patients with knee extensor mechanism injuries but also other disciplines involved in their care, as well as engineers who are interested in knee braces and the biomechanics of the knee joint.