What Is a Midline Incision?

A midline incision is a vertical cut made in the abdomen to allow access for any of a number of medical procedures. This cut may be made in the upper or lower portion of the abdomen, or it may run all the way from the top to the bottom of the abdominal cavity. The midline incision allows the doctor to access the internal organs including the stomach, pancreas, bladder, and liver. It is commonly used during trauma surgery, when immediate access to a wide range of internal organs is essential.

The area of the abdominal cavity requiring access will dictate the type of midline incision that the surgeon chooses to use. In order to reach the top part of the abdomen, an upper midline incision (UMI) is typically used. For the UMI a vertical cut is made starting at the xiphoid process, which is the small, triangular bone that sits at the base of the breastbone. This incision extends down to the umbilicus and gives access to the liver, stomach, spleen, and esophagus.

To gain access to the bottom portion of the abdominal cavity, a lower midline incision is used. The incision in this case typically runs from the umbilicus down to the pubic symphysis. This exposes the uterus, sigmoid colon, and bladder. Such an incision is often used when a surgeon is removing cancers involving the female reproductive organs as well as for other problems, such as hernias.

There are times when it is not certain which area of the abdomen needs to be exposed. This is especially true when the patient has serious trauma and the damaged area is not readily pinpointed. A midline incision that runs the entire length of the abdomen is often used in such cases, and creates an opening from the xiphoid process at the top down to the pubic symphysis at the bottom. Such a cut allows the surgeon to have full view of the entire abdominal area, enabling the doctor to more quickly find and correct problems.

It is important when closing such large openings that care is taken to fully hold together all layers of the abdominal skin and muscle. The surgeon typically closes all layers of tissue, skin, and muscle one at a time, using very small stitches to do so. This helps to prevent a hernia from forming, which can cause serious problems for the patient and in many cases can ultimately require additional surgery.