Evaluation of the Association between Pelvic Diameters and Pelvic Types on Computed Tomography Images in Healthy Turkish Females/Evaluacion de la Asociacion entre Diametros Pelvicos y Tipos de Pelvis en Imagenes de Tomografias Computarizadas en Mujeres Turcas Sanas

Pelvis contributes to both human locomotion and obstetrics, and normal vaginal delivery is associated with a spacious inlet, a large interspinosus diameter. This paper aimed to measure crucial diameters of pelvic ring, and to determine both the prevalence of pelvic types, and labor types including normal vaginal delivery or caesarean section in Turkish healthy females. Additionally, it was aimed to evaluate presence of relationship between pelvic types and pelvic diameters. Labor shape of subjects was obtained from hospital records. This retrospective study was carried out on 165 healthy subjects aged between 18 and 45 years. Anteroposterior diameter of the pelvic inlet (APDI), anteroposterior diameter of the pelvic outlet, sacrum length (SL), sacrum depth, conjugata vera, obstetrical conjugate, the diagonal conjugate, diameter transversa, diameter bispinous, intertuberous diameter were measured. From these measurements, brim index was calculated and decided to gynecoid, anthropoid and platypelloid type. Also, the andoid type was calculated to the ratio of posterior sagittal diameter of the inlet to conjugata obstetrica. 50.91 % of participants has gynecoid type pelvis, followed by 24.85 % anthropoid type, 14.55 % platypelloid, and 9.70 % android type pelvis. There was a significant difference in APDI, SL, SD, Conjugata vera, Conjugata obstetrica, Conjugata diagonalis, Conjugata transversa, diameter bispinous, diameter intertubercularis and Brim index measurements according to pelvic types. the first degree of narrowing (conjugata vera from 11 to 9) was found in 18 pelvises and 12 pelvises with the pathological degree of narrowing bellonged to the platypelloid type followed by android type pelvis with 6 pelvices. The android type pelvis is not appropriate for natural labor and a good assessment of birth canal can reduce the labor risks. Also, only 7 females who delivered with cesarean have gynecoid type pelvic type. The APDI and SL were significantly lower in subjects having pathological narrowing according to conjugata obstetrica values. KEY WORDS: Pelvis diameter; Pelvic shape; Conjugate obstetrica; Caserean or natural labor; Brim index.