Low back pain and motor control dysfunction after pregnancy: The possible role of rectus diastasis

Purpose: Pregnancy-related low back pain is a common condition. Persistent postpartum diastasis recti may cause back pain and motor control dysfunction. The role of diastasis in pregnancy-related back pain remains debatable. This study aimed to compare participants with increased symptoms after index pregnancy with those reporting no change in back pain or subjective movement control and to analyze inter-rectus distance. Materials and Methods: This case-control study included a cohort of women who delivered 1 year earlier. We recruited participants with increased symptoms (n = 14) after index pregnancy and controls (n = 41) and recorded their inter-rectus distance using ultrasound. A questionnaire was completed, and an ultrasound performed twice for each study group. Results: At the baseline, there was no significant difference in inter-rectus distance between cases and controls (mean 2.45 ± 1.01 cm and 2.09 ± 1.03 cm, respectively). A year after index pregnancy symptomatic cases had significantly wider inter-rectus distance than controls (mean 3.45 ± 0.90 cm and 2.40 ± 0.79 cm, respectively). Motor control dysfunction test results were not associated with core stability problems or back pain in this cohort. There was a difference in the sit-up test between cases and controls (mean 4.7 ± 4.2 and 8.2 ± 3.9, respectively). Conclusion: Women who reported increased back pain and core instability after index pregnancy had wider inter-rectus diameter than controls. In the case group with more symptoms after pregnancy, the classification of rectus diastasis (RD) changed from mild abdominal RD (2–3 cm) to moderate (>3–5 cm). RD may contribute to persistent pregnancy-related lumbopelvic pain.