Analysis of multisite surface electromyography characteristics of pelvic floor muscles in postpartum patients with diastasis recti abdominis

Aim: To explore the electrophysiological characteristics of the independent muscles in the pelvic floor muscle (PFM) group of postpartum women with diastasis recti abdominis (DRA) and analyze the correlation between the rectus abdominis interval and PFM function. Methods: A total of 133 women who underwent postpartum re-examination from August 2021 to July 2022 were collected. The participants were divided into DRA and control groups based on the occurrence of DRA on ultrasonography. General data of the participants were collected, and the multisite surface electromyography (sEMG) assessment of the PFMs was performed using a intravaginal novel airbag-type stretchable electrode array device developed by the team. The sEMG characteristics of the different PFMs in the two groups were compared, and the correlation between the maximum rectus abdominis interval and the sEMG parameters of different PFMs was analyzed. Results: There were no differences in the baseline demographics and incidence of pelvic floor dysfunction between the two groups (p > 0.05). The mean amplitude of vaginal sphincter endurance contraction in the DRA group was significantly lower than that in the control group (28.44 +/- 15.59 vs. 22.03 [12.22, 28.00], p < 0.05). Spearman's rank correlation analysis showed a weak negative correlation between the maximum rectus abdominis interval and the endurance contraction mean amplitude of the urethral and external anal sphincters (r = -0.173, -0.217, p < 0.05). Conclusions: Patients with DRA had weakened PFM endurance, and there was a weak negative correlation between the maximum rectus abdominis interval and the endurance contraction mean amplitude of the PFM.