Morphometric evaluation of the linea alba in fresh corpses.

PURPOSE: Diastasis recti abdominis is an increase in the distance between the medial borders of the two rectus muscles. It is most often triggered after intra-abdominal pressure increases, such as postpartum or in obesity. Most publications are based on radiological studies or are done in certain subgroups, without unanimous reference values of the distance between the rectus abdominis or standardization.

METHODS: Forty-one cadavers were studied. Exclusion criteria: signs of abdominal trauma, major burns, presence of scar from previous abdominal surgery, clinical signs of abdominal hernia, and identification of hernia during cadaver dissection. Linea alba (LA) length, width, and thickness were measured with a flexible tape measure and digital caliper. Anatomical landmarks were established, and subdivisions were described based on them to compare the cadavers.

RESULTS: Sex and age had little effect on LA width, thickness, or length. Obesity (compared to normal weight) was the only variable that promoted an increase in the LA width ( p < 0.01). The supraumbilical length varied with the total height of the evaluated cadavers ( p < 0.01), but the infraumbilical length did not ( p = 0.11).

CONCLUSION: The general statistical results of this study, regarding the evaluation of LA measurements in cadavers, showed that ethnicity, sex, and age have little effect on the width, thickness, or length of the LA. LA width differed significantly with abdominal circumference.