Puborectalis Syndrome as a Phenotype of Dyssynergic Defecation in Chronic Constipation: a Comparative Study of Defecography,High-resolution Anorectal Manometry, and Pelvic Floor Ultrasound

Patients with suspected DD who met the Rome IV criteria were divided into the DD group and other types of constipation groups. The differences between the two groups were analyzed to explore the precise diagnostic scheme for DD.

Study Overview

• Status: Completed
• Conditions: Dyssynergic Defecation; Puborectalis Syndrome; Impaired Rectal Evacuation
• Intervention / Treatment: Other: Analysis of inter-group differences

Detailed Description

This study was conducted solely at the Army Specialized Medical Center and was a single-center, bidirectional cohort study. Patients with suspected dyssynergic defecation who visited the constipation specialty clinic of Daping Hospital were collected. After the patients signed the informed consent form, they were asked to fill out the questionnaire (general clinical data questionnaire, Wexner constipation rating scale, ODS rating scale, and constipation patient quality of life scale (PAC-QOL)). The baseline data of the patients (such as age, gender, symptoms, constipation scale scores, intestinal satisfaction scores, etc.) and the results of anorectal manometry, defecography, and perineal ultrasound were statistically analyzed. Patients meeting the Rome IV criteria were grouped through DFG, ARM, and pelvic floor ultrasound examination. The differences in clinical main symptoms, constipation scores, defecography, perineal ultrasound, etc. between the two groups were observed, and the roles and correlations of each parameter in diagnosis were analyzed.

• Study Type: Observational
• Enrollment (Actual): 164

Contacts and Locations

Study Locations

• China
  • Chongqing Municipality
    • Yuzhong, Chongqing Municipality, China, 400042
      • Army Medical Center (Daping Hospital)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

patients with suspected PRS-related DD

Description

Inclusion Criteria:

1. Age ranges from 16 to 85 years old.
2. Constipation patients should meet the Rome Ⅳ criteria for chronic constipation (must include two or more of the following: ① At least 25% of bowel movements are strenuous; ② At least 25% of bowel movements are lumpy or hard stools; ③ At least 25% of bowel movements are accompanied by a sense of incomplete evacuation; ④ At least 25% of bowel movements are associated with a feeling of anorectal obstruction or blockage; ⑤ At least 25% of bowel movements require manual assistance; ⑥ Fewer than 3 bowel movements per week). The healthy volunteer group has no above - mentioned constipation symptoms.
3. Participants should be able to understand and complete relevant questionnaires.
4. Participants should be willing to follow the research protocol and sign the informed consent form.

Exclusion Criteria:

1. Pregnant women and lactating women
2. Suffering from gastrointestinal and other malignant tumors
3. Suffering from diseases such as diabetes and Parkinson's disease
4. Currently participating in other clinical trials

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
patients with suspected PRS-related DD	Other: Analysis of inter-group differences; Analysis of inter-group differences

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rectal emptying rate，（%）	Rectal emptying rate is defined as the reduction in rectal area from pre-evacuation to post-evacuation, expressed as a percentage of the pre-evacuation area, as assessed by defecography.	Baseline assessment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Obstructed Defecation Syndrome score，（ODS score）	the minimum value is 0,and maximum value is 31; a higher scores mean a worse outcome.	Baseline assessment
Cleveland Clinic Constipation Score,(CCCS)	the minimum value is 0,and maximum value is 30; a higher scores mean a worse outcome.	Baseline assessment
Patient Assessment of Constipation Quality of Life total score，（PAC-QOL score）	the minimum value is 0,and maximum value is 112; a higher scores mean a worse outcome.	Baseline assessment
Self-Rating Anxiety Scale score，（SAS score）	the minimum value is 25,and maximum value is 100; a higher scores mean a worse outcome.	Baseline assessment
Bristol Stool Form Scale score	the minimum value is 1,and maximum value is 7; a higher scores mean a worse outcome.	Baseline assessment
Body Mass Index		Baseline assessment
Disease duration,(year)		Baseline assessment
ARA change on DFG，(°)	changes in anorectal angle during defecography	Baseline assessment
Anal canal diameter on DFG，（mm）	anal canal diameter during straining on DFG	Baseline assessment
PRS on DFG	Puborectalis syndrome indicated by the defecography diagnostic report.	Baseline assessment
IRP on DFG	Internal rectal prolapse indicated by the defecography diagnostic report.	Baseline assessment
Rectocele on DFG	Rectocele indicated by the defecography diagnostic report.	Baseline assessment
Anal Resting Pressure，（mmHg）	Anal Resting Pressure measured by High-resolution Anorectal Manometry	Baseline assessment
Anal Squeeze Pressure,(mmHg)	Anal Squeeze Pressure measured by High-resolution Anorectal Manometry	Baseline assessment
Rectal propulsive pressure,(mmHg)	Rectal propulsive pressure measured by High-resolution Anorectal Manometry	Baseline assessment
Anal relaxation rate,(%)	Anal relaxation rate measured by High-resolution Anorectal Manometry during defecation	Baseline assessment
DD on HR-ARM	Dyssynergic defecation(DD) reported by high-resolution anorectal manometry parameters, with diagnostic criteria of rectal pressure during straining >45mmHg and anal canal relaxation rate <20%.	Baseline assessment
ARA change on TPUS,(°)	changes in anorectal angle during evacuation measured by Transperineal Ultrasound	Baseline assessment
Right PRM thickness change on TPUS,(mm)	Changes in right puborectalis muscle thickness during defecation measured by Transperineal Ultrasound	Baseline assessment
Left PRM thickness change on TPUS,(mm)	Changes in left puborectalis muscle thickness during defecation measured by Transperineal Ultrasound	Baseline assessment
PRS on TPUS	Puborectalis syndrome(PRS) indicated by the transperineal ultrasound diagnostic report	Baseline assessment

Collaborators and Investigators

• Sponsor: Third Military Medical University
• Investigators: Study Director: Weidong Tong, MD, Army Medical Center (Daping Hospital)

Study record dates

Study Major Dates

• Study Start (Actual): July 21, 2023
• Primary Completion (Actual): May 31, 2026
• Study Completion (Actual): May 31, 2026

Study Registration Dates

• First Submitted: June 16, 2026
• First Submitted That Met QC Criteria: June 28, 2026
• First Posted (Actual): July 6, 2026

Study Record Updates

• Last Update Posted (Actual): July 6, 2026
• Last Update Submitted That Met QC Criteria: June 28, 2026
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: Defecography; Dyssynergic defecation; Puborectalis syndrome; High-resolution anorectal manometry; Pelvic Floor Ultrasound
• Other Study ID Numbers: PRS202409

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No