The normal width of the linea alba in cadavers – a parameter to define rectus diastasis

Abstract

Objectives: The aim of the present study was to evaluate the width of the linea alba in cadavers with no abdominal wall defects. Methods: Fifty-three fresh adult male cadavers were dissected. The cadavers were placed supine and a xiphopubic incision was made, exposing the myoaponeurotic layer. Two horizontal lines were marked, at 3 cm superiorly and 2 cm inferiorly to the umbilicus, to measure the distance between the recti muscles. Measurements were performed with a digital pachymeter. Statistical analysis was performed using the t-test for 2 independent means where the considered p value was less than 5%. Results: The normality test of the sample revealed no significant variations. The average length of the linea alba and recti muscles were similar (33.02 cm). The mean values for the width of the rectus muscles were 7.37 cm on the right side and 6.84 cm on the left side with no statistical significance between these values (p=0.479). The mean values of the width of the linea alba of the 53 cadavers were 2.17 cm at the supraumbilical level and 1.51 cm at the infraumbilical level; comparing these, a statistically significant difference was observed, with higher values for the supraumbilical level (p=0.034). Conclusion: The width of the alba line was greater at the supraumbilical level and the right abdominal rectus muscle was wider than the left.