Inclusion Criteria:  4-14 years old; Meeting the Roman IV criteria for childhood constipation; After one course of PEG and one course of Chinese medicine treatment, it was ineffective; Pelvic floor surface electromyography (EMG) and 3-D manometry of the anus revealed pelvic floor dysfunction  Exclusion Criteria:meet one of the following criteria to be excluded:  The onset of intestinal stenosis due to organic diseases (such as anal fissure, inflammation, intestinal polyps, intestinal adhesion, Crohn's disease, intestinal tuberculosis, tumor, etc.); constipation due to congenital diseases (such as congenital megacolon, sigmoid colon, etc.); Caused by metabolic endocrine diseases, neurological diseases and mental diseases; Those caused by systemic organic diseases; Patients diagnosed as outlet obstructive constipation and mixed functional constipation; Children with severe systemic diseases; Children with positive occult blood in stool routine examination; Children who refused to participate in PTNS combined with PFR.