Clinical evaluation of x-ray pelvimetry: A study of 1,000 patients in private practice

Abstract

1.1. One thousand patients were studied to evaluate x-ray pelvimetry.2.2. These were all private patients delivered by an associated group, with procedure thereby standardized.3.3. The method of obtaining x-ray mensuration was not as important as the interest and experience of the roentgenologist.4.4. The Johnson and Snow methods were used to obtain pelvic data and the Ball method to obtain fetal data. One roentgenologist in 880 cases used the Johnson method and two, in 120 cases, used the Snow method.5.5. There were 850 primigravidas and 150 multiparas.6.6. Thirty-two inlet, 197 midplane, and 17 outlet contractions were found. Twenty-eight were in combination. No outlet contraction was found to exist alone.7.7. Inlet contractions were no problem. Outlet contractions were not found alone. Midplane contractions, the most common, were studied in detail.8.8. Midplane bi-ischial diameters of less than 9.4 cm., a Mengert Index of less than 84, and the transverse-posterior sagittal index of less than 13.3 cm. in this series were found to be critical. There were exceptions to all indices.9.9. A more consistent curve was found in considering cephalopelvic relationship. When the cephalopelvic disproportion was distinguished in normal and contracted pelves, an even finer dividing line was drawn in the prognosis for safe vaginal delivery.10.10. A large fetal head can be expected to mold to a greater amount than a small fetal head. Disproportion in normal pelves is due to the large fetal head, in contracted pelves to the small pelvic diameters. This explains why greater disproportions are tolerated in normal pelves.11.11. In normal pelves vaginal delivery was the rule until the cephalopelvic disproportion exceeded −200 c.c. In contracted pelves vaginal delivery was limited if the disproportion exceeded −51 c.c.12.12. A successful approach has been to consider the fetal skull volume, the pelvic volumetric capacity, and the clinical appraisal of a given patient.13.13. In no instance, other than frank pelvic deformity, should the roentgenologist dictate obstetrical procedure.14.14. There was a stillbirth rate of 0.7 per cent which included three monstrosities. The neonatal death rate was 0.2 per cent. Prematurity and a cerebral hemorrhage accounted for the two. In no fetal death was a contracted pelvis responsible. Three of these fetal deaths are considered preventable.15.15. There was no maternal mortality.