Splenosis in the abdominal category may occur in up to 65% of traumatic ruptures of the spleen.[3] Splenosis in the thoracic cavity is rarer, because it requires the simultaneous rupture of the diaphragm. The implantation of spleen tissue under the skin may result from abdominal surgery or gunshot wounds. Splenosis of the brain or liver is hypothesized to be the result of tiny pieces of spleen tissue traveling through the bloodstream.