Radiographic evaluation of breech presentation: is it necessary?

Abstract

The purpose of this study was to evaluate the use of ultrasound in identifying fetal position and cervical spine flexion in breech presentations. Radiographic and ultrasonographic determinations of the type of presentation (frank, complete or incomplete) and degree of cervical spine flexion in 52 breech presentations were compared. The angle of flexion was defined as the angle between the fetal mandible and main axis of the cervical spine and categorized as full flexion, military, partial extension and full extension. Ultrasound was concordant with radiographic assessment of the type of presentation in 77% and the angle of flexion in 64% of the subjects and was even more accurate in those in labor. All cases predicted as having full flexion (< 90 degrees C) of the cervical spine by ultrasound had an angle of flexion < or = 90 degrees C on radiographic assessment. Of subjects in labor, ultrasound accurately identified the type of breech presentation in all cases. In addition, sonographic identification of full flexion of the cervical spine excludes cases of fetal neck extension and precludes the need for radiographic assessment prior to a trial of labor.