Medical Definition of ARTHRODESIS. : the surgical immobilization of a joint so that the bones grow solidly together: artificial ankylosis. the surgical immobilization of a joint so that the bones grow solidly together. ADVERTISEMENT.
Trapdoor spiders are not particularly harmful to man however, like Tarantulas, the tiny hairs on the legs of some species leave tiny red marks where the toothed hairs on the spiders' feet have clung to the skin. Mouse spiders are also a type of Trapdoor spider with huge chelicerae and may measure up to 35mm in body length.
The Sydney Funnel Web is not only one of the most poisonous spiders in the world, but one of the most dangerous as well. This is because it lives in populated areas, namely within 100 km from Sydney. This spider is also very aggressive and will definitely attack, if provoked, sometimes biting its victim multiple times.