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.
They are generally small, are harmless to humans, and are found in many warm climates. They also use their burrows for protection and as nest sites, the female spinning her egg sac for about 300 eggs in the burrow. Young Trapdoor spiders stay in the burrow with their mother for some time.