Cylindrical tube attached to the lateral aspect of the left hind joint of the rabbits. The applicator was positioned in such a way that the electromagnetic radiation was aimed towards the joint, with maximum radiation near the joint cavity.
Water (20°C) flowed on the surface of the applicator cooled the skin adjacent to the applicator at the knee joint area. The intraarticular temperature was maintained at 42.5 ± 0.5°C. The right knee was not heated and served as control.