Fatigue amplitude test. Cyclically pulling at fixation element (banjo bolt) and PVDF tendon. Angle between axis of fixation element and tendon about 120 degrees. Lower load 10% of upper load, sinusoidal time dependence of load, 3 cycles per second. Diameter of tendon 2,5 mm. Open triangles: tendon with tight network, open circles: tendon with loose network.