Related Experiment Video
Updated: Jan 29, 2026

Quantification of Levator Ani Hiatus Enlargement by Magnetic Resonance Imaging in Males and Females with Pelvic Organ Prolapse
Published on: April 17, 2019
Anatomic and functional evaluation of the levator ani muscle after an obstetric anal sphincter injury
Eva Martínez Franco1, José Luís López Negre2, David Parés3
1Obstetrics and Gynecology Department, Parc Sanitari Sant Joan de Déu, Universitat de Barcelona, Camí Vell de la Colonia num 25, 08830, Sant Boi de Llobregat, Spain. eva.martinez@pssjd.org.
Purpose:
To study the relationship between symptoms of anal incontinence (AI) and the anatomy and functionality of the levator ani muscle in women with a history of obstetric anal sphincter injury (OASI).
Methods:
This is a cohort study including patients with OASI from 2013 to 2016. Patients were assessed by a physical examination, endoanal ultrasound using Starck Scale, perineometry and 4D transperineal ultrasound. AI in all patients was measured with the Wexner scale. Correlation between variables has been analyzed in these patients.
Results:
72 patients were analyzed: 28 with a IIIA degree tear, 26 with a IIIB, 13 with a IIIC and 5 with a IV. 38 patients showed a residual anal sphincter (AS) defect on endoanal ultrasound with an average Starck score of 6.5 ± 3.7. 21 patients expressed AI, with an average Wexner score of 4.1 ± 2.4. In 27 (37.5%) patients, a levator ani avulsion was observed: 17 unilateral and 10 bilateral. Patients with a levator ani defect had weaker pelvic floor muscle (PFM) function. These differences were statistically significant with perineometry (p = 0.01 and p = 0.03) but not for the Oxford test (p = 0.08). Patients with a residual AS defect as well as an injury to the levator ani muscle expressed greater AI symptomatology than patients with residual sphincter injury who maintain the integrity of the levator ani: Wexner 4.9 0.9 vs 3.3 1 (p = 0.02).
Conclusions:
The PFM has correlation with AI symptom development in patients with a history of OASI. Therefore, we suggest a key role of anatomical and functional assessments of the levator ani muscle in these patients.
More Related Videos
Related Concept Videos
Functions of Smooth Muscles
Function of visceral smooth muscles
Visceral smooth muscle is found in the walls of all hollow organs, except the heart, and is a key player in the involuntary movements that drive the functioning of these internal organs. This tissue is arranged in...
Psychosexual Stages of Personality: Anal
Anatomical Positions
The body is upright, facing forward, and standing erect.
The feet are parallel and flat on the floor.
The arms are hanging by the...
Anatomical Terminology
Anatomical Movements
Here are some common anatomical movements:
Flexion and extension motions are in the sagittal (anterior–posterior) plane of motion. These movements take place at the shoulder, hip, elbow, knee, wrist,...
Cerebrum: Anatomical Overview II

