The knee is the largest and the most complex joint in the human body. It consists of the ligaments, the meniscus, the tendons, the articular cartilage etc. that are responsible for the strengthening, stabilizing and its smooth functioning. The most common injuries of the knee have to do with the rupture or stretching of the ligaments (anterior - posterior cruciate, medial - out lateral ligament), the tear or injury of the meniscus, the cartilage lesions of the patella and rarely the femoral condyles (chondromalacia). Depending on the needs of the patient, the rehabilitation program may include preoperative and/or postoperative conservative treatment or physiotherapy. The first objective is the reduction of pain, inflammation and swelling in the region. At a second stage, and after the inflammation and swelling is decreased, a fitness and knee strengthening program will be implemented.