In 2TP alternately left or right foot was places in front of the other, but the feet were placed on both sides of the line dividing platform to two parts (line was tangent to the medial edge of feet). The length of exercise was 20 s. Analogically to the tandem test, patients were examined with the operated (2TOF) and non operated limb (2 TNF) in the front. Results were compared to the second tandem control index (2TC) representing the mean results of the control group as was described above.