Anatomical Prediction for Surgical Positioning of the Umbilicus in a Croatian Population

The umbilicus is an essential esthetic landmark on the abdominal wall in women and men. There are only few models published for predicting exact localization of the umbilicus. The aim of our study was to develop a mathematical model for predicting correct umbilical positioning in a sample of young women and men and in a sample of middle-aged women. In addition, we wanted to develop a predictive model applicable to both sexes. We applied our models with distinct anthropometric characteristics such as body mass index (BMI) and waist circumference (WC)/hip circumference (HC) to further expand our findings.

In this study, 98 Croatian women and men randomly selected from the University of Zagreb and 46 female patients awaiting abdominoplasty procedure at our institution were included. Anthropometric data and measurements between the umbilicus and fixed bony points around the anterior abdomen were collected. The data collected were body mass (BM), body height (BH), BMI, WC and HC, and waist-hip ratios (WHR). All collected data were subjected to standard statistical analyses.

This study developed 2 different regressive equations for the most accurate prediction of exact umbilical localization. In women, the best prediction of the position of the umbilicus was based on the distance from the interanterior hypochondrium line to the umbilicus using the following regressive equation: u-i-hy = BM × 0.5799 + BH × -0.5051 + BMI × -1.8230 + WHR × -10.6364 + 89.6411. In men, the best prediction of the position of the umbilicus was based on the distance from the umbilicus to the interspinous line using the following regressive equation: u-i-is = age × 0.2033 + BM × 0.6445 + BH × -0.5692 + BMI × -2.2802 + WC × -0.0911 + 101.9408.

We found that age and anthropometric dimensions have a significant influence on the position of the umbilicus on the anterior abdominal wall. The naturally occurring anthropometric variations between women and men made the results of a unique predictive model for umbilical position inaccurate. We found that using 2 distinct predictive models, 1 for both subgroups of women and 1 for men, generated the most accurate predictive results. This quantitative tool should be applied to both women and men for the correct positioning of the umbilicus in reconstructive and esthetic procedures in which the original umbilical location is affected.