ObjectiveTo investigate changes in anal dynamics and anorectal sensory function in patients with irritable bowel syndrome with constipation (IBS-C) and detect its status of basin’s myoelectric pressure. MethodsThirty-six patients with IBS-C (IBS-C group) and 28 healthy volunteers (control group) were collected. The rectal-anal canal pressure and the change of the basin’s myoelectric status were detected by the ZJ-D3 gastrointestinal motility tester and bio-stimulus feedback instrument, respectively. The anal canal resting pressure, rectal resting pressure, anorectal pressure difference, length of anal canal high pressure area, rectal sensation threshold, rectal compliance, and basin’s myoelectric voltage were compared between these two groups. ResultsThere were no significant differences in the rectal resting pressure and anal canal resting pressure between the IBS-C group and the control group (t=–2.312, P=0.851; t=–5.464, P=0.283), but the difference value of anorectal pressure of the IBS-C group was significantly higher than that of the control group (t=4.371, P=0.017), and the length of the anal canal hypertension area in the IBS-C group was significantly longer than that of the control group (t=6.180, P=0.042). The maximal and minimum basin’s myoelectric voltage and frequency of the basin’s myoelectric voltage in the IBS-C group were significantly higher than those in the control group (t=3.386, P=0.031; t=5.763, P=0.042; t=8.410, P<0.001). ConclusionAnorectal dynamics and rectal sensory dysfunction are one of important causes of IBS-C, it might be existed abnormal changes in basin’s myoelectric voltage.