Fistulas can be both hard and soft.
Hard Fistulas
A hard fistula is a type of tunneling wound that is usually caused by surgery, radiation, trauma, or infection. It is characterized by a tunnel-like opening in the skin that connects two parts of the body, such as the skin and underlying tissue. Hard fistulas can be painful and can require surgery for closure.
Radiation can cause hard fistulas due to its effects on the tissue. Radiation damages the tissue, which can lead to inflammation and scarring. This can cause the tissue to become thick and hard, which can create a tunnel-like opening on the skin.
Trauma can also cause hard fistulas. This can occur due to a cut, burn, or other injury to the skin. This can cause the tissue to become thick and hard, which can create a tunnel-like opening on the skin.
Soft Fistulas
A soft fistula is a type of tunneling wound that is usually caused by a condition known as a sinus. It is characterized by an opening in the skin that connects two parts of the body, such as the skin and underlying tissue. Soft fistulas can be painful and can require surgery for closure.
Sinus can cause soft fistulas due to its effects on the tissue. Sinus is an infection of the soft tissue that can lead to inflammation and scarring. This can cause the tissue to become thin and soft, which can create a tunnel-like opening on the skin.
Inflammation can also cause soft fistulas. This can occur due to an infection or irritation of the skin. This can cause the tissue to become thin and soft, which can create a tunnel-like opening on the skin.