External and internal hernias affect different parts of the body. An external hernia affects organs outside of the abdomen wall. The most common types of external hernias are inguinal, femoral, and umbilical. Depending upon its location, an external hernia can affect the groin area (inguinal, femoral) or naval area (umbilical). When an external hernia becomes trapped outside the abdomen wall there's an increased risk that its blood supply will be affected.
Internal hernias like a diaphragmatic hernia can affect the stomach, the esophagus, and diaphragm. If part of the stomach pushes through the opening at the bottom of the diaphragm (hiatus) or a weak area around the hiatus, it affects the digestive system. Internal hernias in other parts of the body are rare but have been known to affect the small intestine, causing obstruction within the intestine