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Updated: May 12, 2026

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Published on: February 12, 2022
Relationship between race and abdominal anatomy: effect on robotic port placement
Brent A Parnell1, Esin C Midia, Julia R Fielding
1Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. bparnell@gru.edu
Objectives:
We sought to characterize differences between African American women and white women in abdominal wall dimensions that could affect robotic port placement. By better understanding these differences, surgeons could assess and adjust port placement to accommodate varying abdominal wall anatomy.
Methods:
A radiologist blinded to race-reviewed abdominal/pelvic computed tomographic scans of women aged 30 to 70 prescreened for demographic inclusion criteria. These consecutive scans were screened for radiologic exclusion criteria until 40 consecutive scans from each race were identified and included.
Results:
Eighty of 663 patients, 40 of each race, met demographic inclusion criteria. The most common radiologic feature disqualifying the scans included absence of the xiphoid process on the scan and anterior abdominal wall deformity. Demographic variables including age, weight, height, and body mass index were similar between groups. Symphysis pubis to umbilicus measurement was shorter in the African American group (15.7 [2.1] vs 17.1 [2.0]; P < 0.001) and intra-anterior superior iliac spine distance was narrower (21.4 [1.2] vs 23.8 [2.0]; P = 0.003), creating an overall smaller lower abdomen in African American women. Total abdominal length was the same between groups (36.6 [2.6] vs 36.7 [2.8]; P = 0.851). Using linear regression, height, weight, and body mass index did not affect lower abdominal dimensions, whereas age (P < 0.001) had a significant inverse relationship with the symphysis pubis to umbilicus measurement.
Conclusions:
Lower abdominal dimensions between races vary, with the umbilicus serving as an inconsistent landmark. Variance exists that can be attributed to racial differences. Assessment of these dimensions at the time of robotic surgery could lead to improved port spacing and therefore fewer arm collisions, improving robotic efficiency.

