Introduction: Faecal incontinence (FI) represents an important psychological and social condition for an individual. There are several causes for FI, therefore its study and management is complex. Among different aetiologies, anatomical disruption of the external anal sphincter (EAS) as a consequence of anorrectal surgery or obstetric injury can be studied by endoanal ultrasound (EAUS). This study focus on anatomical assessment of sphincter muscle injury of EAS and its relationship with clinical presentation con FI. Objective: Compare anatomical and disruption of EAS features studied by 3D-EAUS between patients with FI, according to its severity. Methods: 3D-EAUS images were obtained from selected patients studied for FI between January 2008 and July 2010 at Clínica las Condes. Wexner Score (SW) was used to evaluate severity of FI, dividing patients into two categories: Mild FI (SW < 9) and Severe FI (SW ≥ 9). A single observer evaluated different morphological variables: width, length, percentage and angle of EAS disruption. Parametrical and non-parametrical analysis was used as appropriate. P-value < 0.05 was considered statistically significant. Results: From 31 female patients studied, mean SW was 11.7 ± 0.8 points, range from 5 to 20 points. When dividing into two groups, 9 patients had mild FI and 22 had severe FI. Studied variables in EAUS 3D cubes: width, length, percentage and angle of EAS disruption, did not reach statistical significance between groups. Conclusion: No relationship was found between external anal sphincter anatomic injury variables studied and severity of faecal incontinence.