Pelvic floor magnetic stimulation combined with biofeedback-based electrical stimulation for obstructed defecation syndrome: a retrospective cohort study

Background Obstructed defecation syndrome (ODS) is a clinical syndrome of impaired rectal evacuation that may involve functional and/or structural anorectal abnormalities. Biofeedback-based electrical stimulation (BF-ES) is commonly used in conservative management, while pelvic floor magnetic stimulation (PFMS) is sometimes added in clinical practice. Comparative evidence for the combined regimen remains limited. Methods A retrospective study was conducted in patients with ODS who received systematic treatment at our Pelvic Floor Treatment Center between January 2021 and January 2026. Patients were divided according to their treatment regimen into the BF-ES group and the PFMS plus BF-ES group. A total of 260 patients ( n = 130 per group) were included. All patients underwent an 8-week standardized rehabilitation intervention. Primary outcomes included weekly complete spontaneous bowel movement (CSBM) responder rate and pelvic-floor surface electromyography (sEMG) parameters. Secondary outcomes included weekly laxative-use days, the Constipation Symptom Score (CSS), Traditional Chinese Medicine (TCM) constipation syndrome score, the Patient Assessment of Constipation Quality of Life questionnaire (PAC-QOL), and adverse-event incidence. Results Most baseline covariates met the prespecified balance criterion (SMD < 0.2), although a modest residual imbalance remained in baseline weekly laxative-use days (SMD = 0.243). Compared with BF-ES alone, the PFMS plus BF-ES group had higher CSBM responder and overall response rates (91.5% vs. 80.0% and 97.69% vs. 82.31%, respectively; both P < 0.05), with greater improvements in weekly laxative-use days, TCM constipation syndrome score, PAC-QOL, and selected sEMG parameters (all P < 0.05). Regression analyses showed that baseline laxative use was associated with greater improvement in the TCM constipation syndrome score improvement, whereas laxative use during treatment was associated with less improvement (both P < 0.001). Sex was independently associated with PAC-QOL change ( P < 0.05). Conclusions PFMS plus BF-ES was associated with better clinical outcomes than BF-ES alone in patients with ODS. Prospective randomized controlled trials are warranted to confirm these findings.