Authors

  1. Chiarello, Cynthia M.

Article Content

Purpose/Hypothesis: Diastasis Recti Abdominis (DRA), a midline separation of the recti along the linea alba, may occur during pregnancy, with increasing age, and obesity. DRA diminishes the capacity of the abdominal muscles to stabilize the spine, support the abdomen, and act as prime movers of the trunk. Measuring DRA in cadavers makes it possible to quantify the full extent of this separation. This exploratory study measured length and width (Inter-Recti Distance (IRD)) of the linea alba in embalmed human cadavers to determine the prevalence of DRA, and relate dimensions of the linea alba to subject characteristics. Number of Subjects: Of the 47 cadavers examined, 17 (4 male, 13 female) were excluded due to surgical abdominal scars. Thirty cadavers, 22 male, 8 female, age 82 +/- 7.5 years were included. Materials/Methods: A midline dissection exposed the linea alba. Pins were placed at the medial borders of the rectus abdominis at the umbilicus, 4.5 cm above, and 4.5 cm below the umbilicus. A DRA was defined as an IRD > 27 mm at the umbilicus and > 15 mm above and below the umbilicus. Upon finding a DRA, a thorough dissection was performed to measure the length and width of the entire linea alba and the size of the separation. Digital caliper micrometers were used for all measurements. Intra and inter-rater reliability, established in a previous study, was excellent. Results: Twenty-two bodies (17 male, 5 female) did not exhibit DRA and were considered to be normal. Eight (5 male, 3 female) exhibited DRA with a significantly greater IRD than the normals at each site (p <.000 to .03). Abdominal circumference at the umbilicus was significantly greater in the cadavers that exhibited DRA (p=.000). Multiple regression analyses for each site revealed that 48% of the IRD at the umbilicus (R2 = 0.476, p < .001) and 36% above the umbilicus (R2 = 0.364, p < .007) was explained by age, sex, race, and abdominal circumference. Abdominal circumference was the only significant predictor of DRA ( = 0.634 @ umbilicus, = .607 above, p <.001). Multinomial logistic regression analysis revealed that age, sex, race, and abdominal circumference were appropriate predictors of a cadavers' status as either included or excluded from the study (p< .003). Sex was the only significant predictor of whether a cadaver would be included in the study (2 =16.15, p < .000). When DRA was present, the separation was longer in men and wider in women. However, sex did not distinguish those with from those without DRA (Wald = .846, p < .155). Conclusions: DRA may be more prevalent than previously thought, as 26.7% of the cadavers exhibited a DRA. Those with DRA tended to be older, Caucasian males with a larger abdominal circumference. Clinical Relevance: Understanding of the relationship between DRA, age, sex, race and abdominal circumference will aid the clinician in identifying patients at risk for DRA. While further research is needed, clinicians may be advised to examine patients with impaired abdominal muscle function for DRA.