Rectus diastasis, or diastasis recti, is a condition where the rectus abdominis muscles are no longer located next to each other as they run up and down the abdomen from the breastbone (xyphoid) to the pubic bone (symphysis pubis). The word “diastasis” comes from the Greek word meaning “to separate”. The diastasis is easiest to see when the patient does sit-ups and notices a linear bulge running up the center of the abdomen. The most common cause in women is pregnancy. The majority of women who have had a pregnancy will have some element of stretching of the stomach or rectus abdominis muscles. Heavier men can develop this condition in their upper abdomen from age and weight gain. Rectus diastasis by itself has no risk, because the inner aspect of the abdominal wall is smooth. This means that bowel cannot find its way into a hernia and strangulate. However, the diastasis can be associated with various types of hernias, discomfort of the abdominal wall to touch, poor balance, and a sense of loss of a functional “core”. This loss of core strength can explain back pain that occurs in some patients with severe rectus diastasis. Pregnancy induced rectus diastasis can cause a significant shape change to the abdominal wall, even for very slender patients. Because the tissue between the muscles has been permanently stretched, no amount of exercise will restore the shape of the abdomen. Rectus diastasis is repaired through the surgical technique of an abdominoplasty, or tummy tuck. The skin is lifted near the pubic hair, and elevated to the level of the breastbone. The muscles are tightened in the midline where the tissue had been stretched by pregnancy. Permanent stitches are often used. Extra skin is removed in the underwear or bikini line. Some amount of restretching of the muscles or skin after the procedure can occur.
Because the tissue between the muscles has been permanently stretched, no amount of exercise will restore the shape of the abdomen. However, core strength exercises are often helpful for women to compensate and improve their function. A woman does not need to limit her exercise due to rectus diastasis, as again there is no risk to the bowel from this condition.
The condition of a rectus diastasis can hurt, and many years ago the repair of the stomach muscles was covered under many insurance plans. This is not the case anymore. The repair of a rectus diastasis is considered cosmetic surgery, and the associated expense is not generally covered by insurance plans.
Some women are just as concerned about the functional issues of having a rectus diastasis as they are about the cosmetic issues. When the rectus muscles are no longer attached to each other in the midline, they no longer contract effectively. The upper arms and trunk no longer “push off” against a pressurized abdomen. Women with rectus diastasis do not have a sense of “core”. With rectus diastasis, a lack of coordinated muscle contraction and the expanded size of the abdominal cavity work against effectively raising intra-abdominal pressure. With going up stairs, exercise, or other acts of daily living, a rectus diastasis causes other parts of the body such as the back to work harder. Repair of the rectus diastasis, therefore, often gives patients better use of the torso, and often improves mild lower back pain if it is present.