The pain will be measured with VAS (visual-analogue scale) 4, 8, 12, 24 and 48 hours after the end of operation. At the same time, i.e.: 4, 8, 12, 24 and 48 hours from the end of surgery, the range of flexion and extension in the operated knee will be assessed. Moreover, the possibility of patient's sitting, standing up and walking will be noted.