Predicting the shape of the obturator foramen in the surgical treatment of stress urinary incontinence in women

The aim of the study was to study the possibility of predicting the shape of the obturator foramen depending on the shape of the pelvic bone cavity in the aspect of the surgical treatment of stress urinary incontinence in adult women.

Materials and methods. 61 preparations of the female bone pelvis were studied. A pelviometric form was developed, according to which the linear and angular parameters of the pelvis and obturator foramen, indices of the pelvic cavity and obturator foramen were evaluated. A discriminant analysis was applied to classify the shapes of the obturator foramen.

Results. Based on the calculated pelvic cavity indices, the shape of the pelvic cavity was determined: narrowing to the bottom, cylindrical and widening to the bottom. Using discriminant analysis, a model was developed to predict the shape of the obturator foramen, depending on the shape of the pelvis. Two main forms of the obturator foramen are distinguished: triangular and elliptical. It was found that the triangular form of the obturator foramen is most characteristic of the cylindrical form of the pelvic cavity and to a lesser extent of the downwardly tapering form. The ellipsoidal shape of the obturator foramen predominated in the downwardly expanding pelvic cavity. It is also shown that a narrow under-pelvic angle is characteristic of the downward pelvic cavity and a wide under-pelvic angle is characteristic of the downward dilating pelvis.

Conclusion. The presented index of the lateral deviation of the ischial tubercles makes it possible to determine the shape of the pelvic cavity: narrowing to the bottom, cylindrical and dilating to the bottom. The method of discriminant analysis provides a high degree of certainty in predicting the shape of the obturator foramen, depending on the shape of the pelvic cavity.

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