knee injuries are among the most common problems confronting patients, physical therapist and physicians. since the bony structure provides little stability, the soft tissues are required to withstand high forces, often resulting in tissue overload and injury immobilization of the knee in the presence of a hemarthrosis usually leads to proliferation of intraarticular connective tissue adhesions and pint fibrosis. the physical basis of treating scar tissue is early controlled motion. the management of the knee with increased instability is to strengthening the muscles to properly treat an soft tissue injuries, physical therapist should know about the anatomic structures and biomechanical function of the knee joint, in this review article, we discuss the physiologic properties of soft tissue, biomechanical observation in fibrous connective tissue, managing soft tissue contractures, principles in treating scar tissue and treatment of the knee with increased instability.