Aim: The prevalence and definition of diastasis recti abdominis (DRA) is under debate. This retrospective cross-sectional study evaluated the interrectal distance and the prevalence of DRA in computed tomography (CT) in an asymptomatic population.
Materials and methods: Patients undergoing CT scans for suspected appendicitis or kidney stones from 01/2016 to 12/2018 were screened retrospectively to participate. A study population with equal distribution according to gender and age (18-90 years) was generated (n = 329 patients) and the interrectal distance was measured at six reference points.
Results: DRA (defined as > 2 cm at 3 cm above the umbilicus) was present in 57% of the population. The 80th percentile of the interrectal distance was 10 mm at the xiphoid (median 3 mm, 95% confidence interval (CI) 0-19 mm), 27 mm halfway from xiphoid to umbilicus (median 17 mm, 95% CI 0-39 mm), 34 mm at 3 cm above the umbilicus (median 22 mm, 95% CI 0-50 mm), 32 mm at the umbilicus (median 25 mm, 95% CI 0-45 mm), 25 mm at 2 cm below the umbilicus (median 14 mm, 95% CI 0-39 mm), and 4 mm halfway from umbilicus to pubic symphysis (median 0 mm, 95% CI 0-19 mm). In the multivariate analysis, higher age (p = 0.001), increased body mass index (p < 0.001), and parity (p < 0.037) were independent risk factors for DRA, while split xiphoid, tobacco abuse, and umbilical hernia were not.
Conclusion: The prevalence of DRA is much higher than commonly estimated (57%). The IRD 3 cm above the umbilicus may be considered normal up to 34 mm. To avoid over-treatment, the definition of DRA should be revised.
Keywords: Diastasis recti abdominis; Interrectal distance; Linea alba width; Normal width; Prevalence; Rectus abdominis diastasis.
© 2021. The Author(s).