Can gangrene destroy bones too? If someone had gangrene on their toes like this, or on fingers for example, would they have to disloate the dead part of the limb to get it off? or cut through the bone to separate it?
It doesn't directly attack the bone, but it can cause complications that do. For example, when you start seeing dead tissue (necrosis) on your extremities, the lack of proper blood flow in those areas can cause Osteomyelitis, which is a type of infection that directly effects the bone and the marrow inside of it. In order to prevent an infection like that from spreading to the rest of your body, removal of all dead tissue is required.
Debridement, referring to the removal of dead tissue by surgical or non-surgical means, is the standard therapy for necrosis. Depending on the severity of the necrosis, this may range from removal of small patches of skin, to complete amputation of affected limbs or organs. Chemical removal of necrotic tissue is another option in which enzymatic debriding agents, categorised as proteolytic, fibrinolytic or collagenases, are used to target the various components of dead tissue.[15] In select cases, special maggot therapy using Lucilia sericata larvae has been employed to remove necrotic tissue and infection.[16]
https://en.wikipedia.org/wiki/Necrosis