Abstract
Objective: To compare inter rectus distance (IRD) of pregnant women with pelvic girdle pain (PGP) with those with other types of pregnancy-related back pain (BP).
Study Design: Cross-sectional case-control design.
Background: Abdominal and pelvic muscular stability is reduced in PGP. Compromise to these muscles occurs in diastasis rectus abdominis (DRA), resulting in a larger IRD. There is minimal conflicting research relating to DRA and PGP.
Methods and Measures: The IRD of 66 pregnant women with self-reports of BP was first measured using nylon digital calipers with the abdominal muscles at rest and during a curl-up. All participants were evaluated using a pain location drawing, the numerical rating scale, the posterior pelvic pain provocation test, active straight leg raise, and the sacral compression test. Post hoc, a blinded research assistant classified subjects either into a PGP group if 3 of these tests were positive or into a nonspecific BP group.
Results: In both groups, the IRD was widest at the umbilicus, narrowest below the umbilicus, and decreased with a curl-up. Odds ratios (ORs) were adjusted for factors when a relationship with PGP was suggested as follows: pregnancies 2 or more (OR = 1.07; 95% confidence interval [CI] = 0.40-2.87), weeks of gestation more than 25 (OR = 1.28; 95% CI = 0.49-3.35), and abdominal circumference more than 103 cm (OR = 1.75; 95% CI = 0.65-4.72). The adjusted ORs were very close to 1 with CIs that contain 1, indicating that PGP does not seem to be related to the IRD.
Conclusions: There was no significant difference in the IRD of pregnant women with PGP compared with BP at any location or contraction condition.