Using CT-Based Pelvimetry and Visceral Obesity Measurements to Predict Total Mesorectal Excision Quality for Patients Undergoing Rectal Cancer Surgery.

BACKGROUND: A complete total mesorectal excision is the criterion standard in curative rectal cancer surgery. Ensuring quality is challenging in a narrow pelvis, and obesity amplifies technical difficulties. Pelvimetry is the measurement of pelvic dimensions, but its role in gauging preoperatively the difficulty of proctectomy is largely unexplored. OBJECTIVE: To determine pelvic structural factors associated with incomplete total mesorectal excision after curative proctectomy and build a predictive model for total mesorectal excision quality. DESIGN: Retrospective cohort study. SETTING: A quaternary referral center database of patients diagnosed with rectal adenocarcinoma (2009-2017). PATIENTS: Curative-intent proctectomy for rectal adenocarcinoma. INTERVENTIONS: All radiological measurements were obtained from preoperative CT images using validated imaging processing software tools. Completeness of total mesorectal excision was obtained from histology reports. MAIN OUTCOME MEASURES: Ability of radiological pelvimetry and obesity measurements to predict total mesorectal excision quality. RESULTS: Of the 410 cases meeting inclusion criteria, 362 underwent a complete total mesorectal excision (88%). Multivariable regression identified a deeper sacral curve (per 100 mm 2 [OR: 1.14; 95% CI, 1.06-1.23; p < 0.001]) and a greater transverse distance of the pelvic outlet (per 10 mm [OR:1.41, 95% CI, 1.08-1.84; p = 0.012]) to be independently associated with incomplete total mesorectal excision. An increased area of the pelvic inlet (per 10 cm 2 [OR: 0.85; 95% CI, 0.75-0.97; p = 0.02) was associated with a higher rate of complete mesorectal excision. No difference in visceral obesity ratio and visceral obesity (ratio >0.4 vs <0.4) between BMI (<30 vs ≥30) and sex was identified. A model was built to predict mesorectal quality using the following variables: depth of sacral curve, area of pelvic inlet, and transverse distance of the pelvic outlet. LIMITATIONS: Retrospective analysis is not controlled for the choice of surgical approach. CONCLUSIONS: Pelvimetry predicts total mesorectal excision quality in rectal cancer surgery and can alert surgeons preoperatively to cases of unusual difficulty. This predictive model may contribute to treatment strategy and aid in the comparison of outcomes between traditional and novel techniques of total mesorectal excision. See Video Abstract . USO DE MEDICIONES DE PELVIMETRA Y OBESIDAD VISCERAL BASADAS EN TC PARA PREDECIR LA CALIDAD DE TME EN PACIENTES SOMETIDOS A CIRUGA DE CNCER DE RECTO: ANTECEDENTES:Una escisión mesorrectal total y completa es el estándar de oro en la cirugía curativa del cáncer de recto. Garantizar la calidad es un desafío en una pelvis estrecha y la obesidad amplifica las dificultades técnicas. La pelvimetría es la medición de las dimensiones pélvicas, pero su papel para medir la dificultad preoperatoria de la proctectomía está en gran medida inexplorado.OBJETIVO:Determinar los factores estructurales pélvicos asociados con la escisión mesorrectal total incompleta después de una proctectomía curativa y construir un modelo predictivo para la calidad de la escisión mesorrectal total.DISEÑO:Estudio de cohorte retrospectivo.ÁMBITO:Base de datos de un centro de referencia cuaternario de pacientes diagnosticados con adenocarcinoma de recto (2009-2017).PACIENTES:Proctectomía con intención curativa para adenocarcinoma de recto.INTERVENCIONES:Todas las mediciones radiológicas se obtuvieron a partir de imágenes de TC preoperatorias utilizando herramientas de software de procesamiento de imágenes validadas. La integridad de la escisión mesorrectal total se obtuvo a partir de informes histológicos.PRINCIPALES MEDIDAS DE VALORACIÓN:Capacidad de la pelvimetría radiológica y las mediciones de obesidad para predecir la calidad total de la escisión mesorrectal.RESULTADOS:De los 410 casos que cumplieron los criterios de inclusión, 362 tuvieron una escisión mesorrectal total completa (88%). Una regresión multivariable identificó una curva sacra más profunda (por 100 mm2); OR:1,14,[IC95%:1,06-1,23,p<0,001], y mayor distancia transversal de salida pélvica (por 10mm); OR:1,41, [IC 95%:1,08-1,84,p=0,012] como asociación independiente con escisión mesorrectal total incompleta. Un área aumentada de entrada pélvica (por 10 cm2); OR:0,85, [IC95%:0,75-0,97,p=0,02] se asoció con una mayor tasa de escisión mesorrectal completa. No se identificaron diferencias en la proporción de obesidad visceral y la obesidad visceral (proporción>0,4 vs.<0,4) entre el índice de masa corporal (<30 vs.>=30) o el sexo. Se construyó un modelo para predecir la calidad mesorrectal utilizando variables: profundidad de la curva sacra, área de la entrada pélvica y distancia transversal de la salida pélvica.LIMITACIONES:Análisis retrospectivo no controlado por la elección del abordaje quirúrgico.CONCLUSIONES:La pelvimetría predice la calidad de la escisión mesorrectal total en la cirugía del cáncer de recto y puede alertar a los cirujanos preoperatoriamente sobre casos de dificultad inusual. Este modelo predictivo puede contribuir a la estrategia de tratamiento y ayudar en la comparación de resultados entre técnicas tradicionales y novedosas de escisión mesorrectal total. (Traducción- Dr. Ingrid Melo).

Effects of applying high-pass filtering in pelvimetry with Martius images.

AIM: The aim of this study is to investigate whether the results of pelvimetry using original radiographic Martius images and the same images with high-pass filtering applied ("edge images") would be consistent. METHODS: A total of 30 primagravidas were included in this study. Three obstetricians independently measured the anteroposterior and transverse diameters of the pelvic inlet in the original and the edge images, recording the x- and y-coordinates of the four endpoints. A Wilcoxon signed rank sum test was performed on the coordinate data to evaluate differences between the original and edge images. RESULTS: In the analysis of all coordinate data, statistically significant differences were found in both x- and y-coordinates of the sacral promontory point (SPP). In the y-coordinate of the SPP, a statistically significant difference was found in 9 of 30 pairs of images, and in all 9 the anteroposterior diameter was shorter in the edge images compared to the original images due to the more caudal placement of the SPP. CONCLUSIONS: The coordinates of the SPP on original radiographs and their edge images were not consistent in pelvimetry using Martius images. Our results suggest that improved image contrast will allow obstetricians to better assess pelvic narrowing and cephalopelvic disproportion and even reduce radiographic dose, thereby reducing risks for pregnant women and their fetuses.

Simple pelvimetry predicts the pelvic manipulation time in robot-assisted low and ultra-low anterior resection for rectal cancer.

PURPOSE: This study explored the difficulty factors in robot-assisted low and ultra-low anterior resection, focusing on simple measurements of the pelvic anatomy. METHODS: This was a retrospective analysis of the clinical data of 61 patients who underwent robot-assisted low and ultra-low anterior resection for rectal cancer between October 2018 and April 2023. The relationship between the operative time in the pelvic phase and clinicopathological data, especially pelvic anatomical parameters measured on X-ray and computed tomography (CT), was evaluated. The operative time in the pelvic phase was defined as the time between mobilization from the sacral promontory and rectal resection. RESULTS: Robot-assisted low and ultra-low anterior resections were performed in 32 and 29 patients, respectively. The median operative time in the pelvic phase was 126 (range, 31-332) min. A multiple linear regression analysis showed that a short distance from the anal verge to the lower edge of the cancer, a narrow area comprising the iliopectineal line, short anteroposterior and transverse pelvic diameters, and a small angle of the pelvic mesorectum were associated with a prolonged operative time in the pelvic phase. CONCLUSION: Simple pelvic anatomical measurements using abdominal radiography and CT may predict the pelvic manipulation time in robot-assisted surgery for rectal cancer.

Pelvic inlet area is associated with birth mode.

INTRODUCTION: To determine whether a pelvis is wide enough for spontaneous delivery has long been the subject of obstetric research. A number of variables have been proposed as predictors, all with limited accuracy. In this study, we use a novel three-dimensional (3D) method to measure the female pelvis and assess which pelvic features influence birth mode. We compare the 3D pelvic morphology of women who delivered vaginally, women who had cesarean sections, and nulliparous women. The aim of this study is to identify differences in pelvic morphology between these groups. MATERIAL AND METHODS: This observational study included women aged 50 years and older who underwent a CT scan of the pelvis for any medical indication. We recorded biometric data including height, weight, and age, and obtained the obstetric history. The bony pelvis was extracted from the CT scans and reconstructed in three dimensions. By placing 274 landmarks on each surface model, the pelvises were measured in detail. The pelvic inlet was measured using 32 landmarks. The trial was registered at the German Clinical Trials Register DRKS (DRKS00017690). RESULTS: For this study, 206 women were screened. Exclusion criteria were foreign material in the bony pelvis, unknown birth mode, and exclusively preterm births. Women who had both a vaginal birth and a cesarean section were excluded from the group comparison. We compared the pelvises of 177 women between three groups divided by obstetric history: vaginal births only (n = 118), cesarean sections only (n = 21), and nulliparous women (n = 38). The inlet area was significantly smaller in the cesarean section group (mean = 126.3 cm2 ) compared with the vaginal birth group (mean = 134.9 cm2 , p = 0.002). The nulliparous women were used as a control group: there was no statistically significant difference in pelvic inlet area between the nulliparous and vaginal birth groups. CONCLUSIONS: By placing 274 landmarks on a pelvis reconstructed in 3D, a very precise measurement of the morphology of the pelvis is possible. We identified a significant difference in pelvic inlet area between women with vaginal delivery and those with cesarean section. A unique feature of this study is the method of measurement of the bony pelvis that goes beyond linear distance measurements as used in previous pelvimetric studies.

BMI and pelvimetry help to predict the duration of laparoscopic resection for low and middle rectal cancer.

BACKGROUND: In rectal cancer surgery, recent studies have found associations between clinical factors, especially pelvic parameters, and surgical difficulty; however, their findings are inconsistent because the studies use different criteria. This study aimed to evaluate common clinical factors that influence the operative time for the laparoscopic anterior resection of low and middle rectal cancer. METHODS: Patients who underwent laparoscopic radical resection of low and middle rectal cancer from January 2018 to December 2020 were retrospectively analyzed and classified according to the operative time. Preoperative clinical and magnetic resonance imaging (MRI)-related parameters were collected. Logistic regression analysis was used to identify factors for predicting the operative time. RESULTS: In total, 214 patients with a mean age of 60.3 ± 8.9 years were divided into two groups: the long operative time group (n = 105) and the short operative time group (n = 109). Univariate analysis revealed that the male sex, a higher body mass index (BMI, ≥ 24.0 kg/m2), preoperative treatment, a smaller pelvic inlet (< 11.0 cm), a deeper pelvic depth (≥ 10.7 cm) and a shorter intertuberous distance (< 10.1 cm) were significantly correlated with a longer operative time (P < 0.05). However, only BMI (OR 1.893, 95% CI 1.064-3.367, P = 0.030) and pelvic inlet (OR 0.439, 95% CI 0.240-0.804, P = 0.008) were independent predictors of operative time. Moreover, the rate of anastomotic leakage was higher in the long operative time group (P < 0.05). CONCLUSION: Laparoscopic rectal resection is expected to take longer to perform in patients with a higher BMI or smaller pelvic inlet.

Impact of pelvic dimensions on anastomotic leak after anterior resection for patients with rectal cancer.

AIM: The impact of pelvis on the development of anastomotic leak (AL) in rectal cancer (RC) patients who underwent anterior resection (AR) remains unclear. The aim of this study was to evaluate the impact of pelvic dimensions on the risk of AL. METHODS: A total of 1058 RC patients undergoing AR from January 2013 to January 2016 were enrolled. Pelvimetric parameters were obtained using abdominopelvic computed tomography scans. RESULTS: Univariate analyses showed that pelvic inlet, pelvic outlet, interspinous distance, and intertuberous distance were significantly associated with the risk for AL (P < 0.05). Multivariate analysis confirmed that pelvic inlet and intertuberous distance were independent risk factors for AL (P < 0.05). Significant factors from multivariate analysis were assembled into the nomogram A (without pelvic dimensions) and nomogram B (with pelvic dimensions). The area under curve (AUC) of nomogram B was 0.72 (95% CI 0.67-0.77), which was better than the AUC of nomogram A (0.69, [95% CI 0.65-0.74]), but didn't reach a statistical significance (P = 0.199). Decision curve supported that nomogram B was better than nomogram A. CONCLUSION: Pelvic dimensions, specifically pelvic inlet and intertuberous distance, seemed to be independent predictors for postoperative AL in RC patients. Pelvic inlet and intertuberous distance incorporated with preoperative radiotherapy, preoperative albumin, conversion, and tumor diameter in the nomogram might provide a clinical tool for predicting AL.

Clinical evaluation of labor: an evidence- and experience-based approach.

During labor mother and fetus are evaluated at intervals to assess their well-being and determine how the labor is progressing. These assessments require skillful physical diagnosis and the ability to translate the acquired information into meaningful prognostic decision-making. We describe a coordinated approach to the assessment of labor. Graphing of serial measurements of cervical dilatation and fetal station creates "labor curves," which provide diagnostic and prognostic information. Based on these curves we recognize nine discrete labor abnormalities. Many may be related to insufficient or disordered contractile mechanisms. Several factors are strongly associated with development of labor disorders, including cephalopelvic disproportion, excess analgesia, fetal malpositions, intrauterine infection, and maternal obesity. Clinical cephalopelvimetry involves assessing pelvic traits and predicting their effects on labor. These observations must be integrated with information derived from the labor curves. Exogenous oxytocin is widely used. It has a high therapeutic index, but is easily misused. Oxytocin treatment should be restricted to situations in which its potential benefits clearly outweigh its risks. This requires there be a documented labor dysfunction or a legitimate medical reason to shorten the labor. Normal labor and delivery pose little risk to a healthy fetus; but dysfunctional labors, especially if stimulated excessively by oxytocin or terminated by complex operative vaginal delivery, have the potential for considerable harm. Conscientiously implemented, the approach to the evaluation of labor outlined in this review will result in a reasonable cesarean rate and minimize risks that may accrue from the labor and delivery process.

MRI pelvimetry-based evaluation of surgical difficulty in laparoscopic total mesorectal excision after neoadjuvant chemoradiation for male rectal cancer.

PURPOSE: Laparoscopic total mesorectal excision (LaTME) is technically demanding in rectal cancer after neoadjuvant chemoradiotherapy (NCRT). This study aimed to predict the surgical difficulty of LaTME after NCRT based on pelvimetric parameters. METHODS: This study enrolled 147 patients who underwent LaTME after NCRT. The surgical difficulty was graded as high or low according to the operative time, estimated blood loss, conversion to open surgery, postoperative hospital stay, and postoperative complications. Pelvimetry parameters were collected based on preoperative MRI. A logistic regression analysis was performed to identify predictors of high surgical difficulty, and a nomogram was developed. RESULTS: Totally, 18 (12.2%) patients were graded as high surgical difficulty. High surgical difficulty was correlated with a shorter interspinous distance (P = 0.014), a small angle α and γ (P = 0.008, P = 0.008, respectively), and a larger mesorectal area and mesorectal fat area (P = 0.041, P = 0.046, respectively). Tumor distance from the anal verge (OR = 0.619, P = 0.024), tumor diameter (OR = 3.747, P = 0.004), interspinous distance (OR = 0.127, P = 0.007), and angle α (OR = 0.821, P = 0.039) were independent predictors of high surgical difficulty. A predictive nomogram was developed with a C-index of 0.867. CONCLUSION: A shorter tumor distance from the anal verge, larger tumor diameter, shorter interspinous distance, and smaller angle α could help to predict high surgical difficulty of LaTME in male LARC patients after NCRT.

Asymmetric pelvis and term breech presentation: is planned vaginal delivery still a safe option?

PURPOSE: To evaluate the obstetrical prognosis of term breech delivery in case of asymmetric pelvis. METHODS: An observational, comparative, retrospective, bi-centric study of 559 patients who had a computer tomography pelvimetry prior to delivery of a term breech presentation was conducted between August 2013 and August 2019. Patients with an attempted vaginal delivery were divided into two groups: a group of asymmetric pelvis (AP) when the difference between the lengths of both oblique diameters was ≥ 1 cm and a group of symmetric pelvis (SP) when the two oblique diameters differed by < 1 cm. The primary outcome was the rate of vaginal delivery. Secondary outcomes were a composite variable of neonatal and maternal morbidity and mortality. RESULTS: Of the 370 patients who attempted a vaginal breech delivery, 8% (n = 29) had an AP and 92% (n = 341) had a SP. In the AP group, the vaginal delivery rate was higher (93% versus 78%, p = 0.05). There was no statistically significant difference in neonatal (3% versus 1% in the AP and SP groups, respectively, p = 0.4) and maternal (17% versus 23% in the AP and SP groups, respectively, p = 0.5) morbidity and mortality. CONCLUSION: When a pelvimetry is performed before an attempt of vaginal breech delivery, a difference of less than two centimetres between both oblique diameters does not seem to reduce the rate of vaginal birth and is not an indication for an elective caesarean section.

Prediction of transabdominal total mesorectal excision difficulty according to the angle of pelvic floor muscle.

BACKGROUND: Total mesorectal excision (TME) is challenging to perform in a deep, narrow pelvis. While previous studies used pelvimetry to assess bony pelvic structures, there is no consensus on exact definition of deep, narrow pelvis. We hypothesized that the shape of pelvic floor muscle may impact the performance of transabdominal pelvic dissection. We aimed to evaluate which parameters of the shape of pelvic floor muscle impact the difficulty of TME and present a predictive reference value for TME difficulty. METHODS: From January 2015 to December 2015, 85 consecutive patients who had undergone curative resection for middle to lower rectal cancer were retrospectively studied. Pelvimetry was performed using preoperative T2-weighted magnetic resonance imaging. Predictive factor analysis for surgical duration was studied using linear regression. Mann-Whitney U test, comparing surgical duration between two groups classified by predictive factor, was used for the analysis of reference value. RESULTS: Multivariate analysis revealed that body mass index, protective stoma, number of surgeon, and incline angle of pelvic floor muscle (ß) were independent predictors of surgical duration. Test statistics of Mann-Whitney U for the difference in surgical duration between groups above and below a ß of 54° were maximized. CONCLUSIONS: The incline angle of pelvic floor muscle is an independent predictor of surgical duration. In patients with steeper incline of PFM, transabdominal TME is expected to be difficult. This index is novel, but needs to be further validated.

Reliability of pelvimetry is affected by observer experience but not by breed and sex: A cross-sectional study in beef cattle.

Pelvis size plays an important role to prevent dystocia in cattle caused by the foeto-maternal disproportion in commonly primiparous females. The reproducibility and repeatability are two important aspects for the reliability of the measurements to use in the selection of cattle for culling. Pelvic measures were taken with a Rice pelvimeter from 224 young cattle (180 females and 44 males) of four beef breeds in South Africa. One experienced and two inexperienced observers each measured pelvic height and width twice. The proportion measurements with a maximum difference of 0.5 cm within animal compared with the first measurement by the experienced observer are around 80% and by the inexperienced observers around 50% for pelvic height and around 60% for pelvic width. Breed and sex do not affect the reliability of pelvimetry by an experienced observer. Under- and overestimation of pelvis size were observed in inexperienced observers, which seems to be unrelated to breed and sex.

Pelvic inlet shape measured by three-dimensional pelvimetry is a predictor of the operative time in the anterior resection of rectal cancer.

PURPOSE: We evaluated pelvic shape as a predictor of the surgical outcome of anterior resection in patients with rectal cancer. METHODS: In total, 228 patients who had undergone anterior resection (R0 resection and double-stapling anastomosis) for rectal cancer from 2005 to 2014 were included in this study. The anteroposterior (AP) and transverse (T) diameters of the pelvic inlet and outlet and pelvic depth were analyzed on three-dimensional volume-rendered images, and the AP/T ratio was calculated. Univariate and multivariate analyses were performed to determine the predictive significance of the operative time and intraoperative blood loss as surgical outcomes. RESULTS: No difference was observed between the inlet AP/T and patient sex ratios, but the other pelvic dimensions were significantly shorter in males than in females. The univariate analysis revealed that the operative time was significantly correlated with the inlet T diameter and that it tended to be correlated with the outlet T diameter and the inlet AP/T ratio. A multivariate analysis adjusted for operation-related factors revealed that the inlet AP/T ratio was the only independent risk factor for an extended operative time (p = 0.036). None of the pelvic dimensions were independent risk factors for increased blood loss. CONCLUSION: The shape of the pelvic inlet may be useful for predicting the operative time.

Magnetic resonance-based pelvimetry and tumor volumetry can predict surgical difficulty and oncologic outcome in locally advanced mid-low rectal cancer.

PURPOSE: To investigate the impact of the pelvic dimensions and tumor volume on surgery in locally advanced rectal cancer. METHODS: Patients who underwent open surgery after neoadjuvant long-course chemoradiation for primary rectal cancer were included. The predictive value of magnetic resonance-based pelvic measurements and tumor volume on the surgical difficulty and oncologic outcome were analyzed. RESULTS: 125 patients were included. The independent risk factors related to the circumferential resection margin status were the pT stage [odds ratio (OR) 3.64, confidence interval (CI) 1.409-7.327] and tumor volume after neoadjuvant chemoradiotherapy (OR 1.59, CI 1.018-2.767). The operative time (p = 0.014, OR 1.453) and pelvic depth (p = 0.023, OR 1.116) were independent predictive factors for anastomotic leak. The median follow-up was 72 (2-113) months. Local recurrence was seen in 17 (14.1%) patients. Anastomotic leak (OR 1.799, CI 0.978-3.277), the circumferential resection margin status (OR 3.217, CI 1.262-7.870) and the relative tumor volume rate (OR 1.260, CI 1.004-1.912) were independent prognosticators of local recurrence. The 5-year overall survival was 66.7%. The circumferential resection margin status (hazard ratio: 4.739, CI 2.276-9.317), pN stage (OR 3.267, CI 1.195-8.930) and relative tumor volume rate (OR 2.628, CI 1.042-6.631) were independent prognostic factors for the overall survival. CONCLUSIONS: Relative dimensions of the tumor in the pelvis influence the local recurrence and overall survival rates. Magnetic resonance-based measurements can predict the difficulty of surgery and allow surgeons to consider the appropriate surgical approach.

Study on the cephalopelvic relationship with cephalic presentation in nulliparous full-term Chinese pregnant women by MRI with three-dimensional reconstruction.

PURPOSE: To analyze the relationship between fetal head size and maternal pelvis size using magnetic resonance imaging (MRI) with a 3-D reconstruction technique. METHODS: A total of 301 nulliparous full-term Chinese pregnant women with cephalic presentation were enrolled and received MRI examinations before labor onset. Data were collected and imported into Mimics software to reconstruct the maternal pelvis and fetus. RESULTS: Of 301 pregnant women, 212 underwent vaginal delivery and 32 received cesarean section. The body mass index (BMI) was significantly different between the vaginal delivery group and the suspected cephalopelvic disproportion (CPD) group; the larger the BMI, the higher was the risk of CPD. The transverse diameter of the pelvic inlet and the posterior sagittal diameter of the midpelvis were significantly larger in the vaginal delivery group, compared with the suspected CPD group. Fetal weight > 3.5 kg could be used as a diagnostic indicator for CPD. CONCLUSIONS: BMI is a risk factor for CPD, and fetal weight < 3.5 kg is an important diagnostic indicator for natural delivery in Chinese pregnant women.

The pelvic radius technique in the assessment of spinopelvic sagittal alignment of degenerative spondylolisthesis and lumbar spinal stenosis.

BACKGROUND: Degenerative spondylolisthesis (DS) and lumbar spinal stenosis (LSS) are the most common degenerative spinal diseases. The evaluating of spinopelvic sagittal alignment of the two diseases using pelvic radius (PR) technique have not been reported. The purpose of this study was to use PR measurement technique to compare the differences in spinopelvic sagittal alignment between DS and LSS. METHODS: A total of 145 patients with DS or LSS were retrospectively reviewed. Seventy patients with DS (DS group) and 75 age-matched patients with LSS (LSS group) were enrolled. Spinopelvic parameters including pelvic angle (PA), regional lumbopelvic lordosis (PR-L1, PR-L2, PR-L3, PR-L4 and PR-L5), total lumbopelvic lordosis (PR-T12), pelvic morphology (PR-S1), sagittal vertical axis from the C7 plumb line (SVA), lumbar lordosis (LL), thoracic kyphosis (TK), L4 slope and L5 slope were assessed in the two groups. Several parameters of DS and LSS group were compared with the normal population (NP). RESULTS: The PR-L4, PR-L5 and PR-S1 in the DS group were significantly smaller than those in the LSS group. There was no difference in PR-T12 between the DS group and NP (p > 0.05), while PR-T12 of the LSS group were significantly lower (p < 0.01). Degree of correlations among spinopelvic parameters differed between the two groups. PR-T12 of the DS group was more strongly correlated with PA (r = -0.829, p < 0.001) than with LL (r = 0.664, p < 0.001), TK (r = 0.582, p < 0.001). PR-T12 of the LSS group was more strongly correlated with LL (r = 0.854, p < 0.001), TK (r = 0.616, p < 0.001) than with PA (r = -0.582, p < 0.001). CONCLUSIONS: PR-L4 and PR-L5 may be the predisposing factors for DS development. Spinopelvic morphology differed in patients with DS and LSS compared to NP. The compensatory mechanisms to maintain spinopelvic sagittal alignment in DS and LSS patients may be different.

Pelvimetry for fetal cephalic presentations at or near term for deciding on mode of delivery.

BACKGROUND: Pelvimetry assesses the size of a woman's pelvis aiming to predict whether she will be able to give birth vaginally or not. This can be done by clinical examination, or by conventional X-rays, computerised tomography (CT) scanning, or magnetic resonance imaging (MRI). OBJECTIVES: To assess the effects of pelvimetry (performed antenatally or intrapartum) on the method of birth, on perinatal mortality and morbidity, and on maternal morbidity. This review concentrates exclusively on women whose fetuses have a cephalic presentation. SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2017) and reference lists of retrieved studies. SELECTION CRITERIA: Randomised controlled trials (including quasi-randomised) assessing the use of pelvimetry versus no pelvimetry or assessing different types of pelvimetry in women with a cephalic presentation at or near term were included. Cluster trials were eligible for inclusion, but none were identified. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the quality of the evidence using the GRADE approach. MAIN RESULTS: Five trials with a total of 1159 women were included. All used X-ray pelvimetry to assess the pelvis. X-ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that examined other types of radiological pelvimetry or that compared clinical pelvimetry versus no pelvimetry.The included trials were generally at high risk of bias. There is an overall high risk of performance bias due to lack of blinding of women and staff. Two studies were also at high risk of selection bias. We used GRADEpro software to grade evidence for our selected outcomes; for caesarean section we rated the evidence low quality and all the other outcomes (perinatal mortality, wound sepsis, blood transfusion, scar dehiscence and admission to special care baby unit) as very low quality. Downgrading was due to risk of bias relating to lack of allocation concealment and blinding, and imprecision of effect estimates.Women undergoing X-ray pelvimetry were more likely to have a caesarean section (risk ratio (RR) 1.34, 95% confidence interval (CI) 1.19 to 1.52; 1159 women; 5 studies; low-quality evidence). There were no clear differences between groups for perinatal outcomes: perinatal mortality (RR 0.53, 95% CI 0.19 to 1.45; 1159 infants; 5 studies; very low-quality evidence), perinatal asphyxia (RR 0.66, 95% CI 0.39 to 1.10; 305 infants; 1 study), and admission to special care baby unit (RR 0.20, 95% CI 0.01 to 4.13; 288 infants; 1 study; very low-quality evidence). Other outcomes assessed were wound sepsis (RR 0.83, 95% CI 0.26 to 2.67; 288 women; 1 study; very low-quality evidence), blood transfusion (RR 1.00, 95% CI 0.39 to 2.59; 288 women; 1 study; very low-quality evidence), and scar dehiscence (RR 0.59, 95% CI 0.14 to 2.46; 390 women; 2 studies; very low-quality evidence). Again, no clear differences were found for these outcomes between the women who received X-ray pelvimetry and those who did not. Apgar score less than seven at five minutes was not reported in any study. AUTHORS' CONCLUSIONS: X-ray pelvimetry versus no pelvimetry or clinical pelvimetry is the only comparison included in this review due to the lack of trials identified that used other types or pelvimetry (other radiological examination or clinical pelvimetry versus no pelvimetry). There is not enough evidence to support the use of X-ray pelvimetry for deciding on mode of delivery in women whose fetuses have a cephalic presentation. Women who undergo an X-ray pelvimetry may be more likely to have a caesarean section.Further research should be directed towards defining whether there are specific clinical situations in which pelvimetry can be shown to be of value. Newer methods of pelvimetry (CT, MRI) should be subjected to randomised trials to assess their value. Further trials of X-ray pelvimetry in cephalic presentations would be of value if large enough to assess the effect on perinatal mortality.

MR pelvimetry: prognosis for successful vaginal delivery in patients with suspected fetopelvic disproportion or breech presentation at term.

PURPOSE: The purpose of this study was to correlate MR pelvimetric pelvic inlet measurements with mode of delivery and neonatal outcome in patients with suspected fetopelvic disproportion or breech presentation. METHODS: For this retrospective monocentric study, 237 consecutive MR pelvimetry reports (1999-2016) of pregnant women due to either suspected fetopelvic disproportion, pelvic deformation after trauma, or persistent breech presentation were retrieved from the radiologic database and matched with corresponding information from the obstetric database. RESULTS: Of 223 included women, 95 (42.6%) underwent planned cesarean section (pCS) and 128 (57.4%) underwent a trial of vaginal labour (TOL), of whom 93 (72.7%) delivered vaginally. Vaginal delivery was successful in 45 out of 64 (70.3%) cephalic cases and in 48 out of 64 (75.0%) breech cases. We found statistically significant differences in conjugata vera obstetrica (CV) and diameter transversalis (DT) between the groups TOL and pCS (CV: 12.5 ± 1.0 vs 12.1 ± 1.2 cm, p value 0.001; DT: 13.3 ± 0.9 vs 12.7 ± 0.9 cm, p value <0.001, respectively). However, there was no significant difference between successful VD and cesarean section after TOL (CV: 12.5 ± 0.9 vs 12.3 ± 1.1 cm, p value 0.194; DT: 13.4 ± 0.9 vs 13.2 ± 0.9 cm, p value 0.358, respectively). CONCLUSIONS: In our cohort, MR pelvimetry was a useful tool for prepartal assessment of the female pelvis in the selection of TOL candidates. Yet, it does not seem to yield additional predictive value for women with a previous vaginal delivery.

Determining the Incidence of Gynecoid Pelvis Using Three-Dimensional Computed Tomography in Nonpregnant Multiparous Women.

OBJECTIVES: To determine the incidence of gynecoid pelvis by using classical criteria and measured parameters obtained from three-dimensional computed tomography (3D CT) pelvimetry in nonpregnant multiparous women who delivered vaginally. SUBJECTS AND METHODS: Our hospital's picture archiving and communication system was reviewed retrospectively. All adult women who had undergone CT examination with routine abdominal protocols were identified. In the pelvic inlet, midpelvis, and pelvic outlet, classical criteria and measured parameters, both alone and in combination, were used to determine the presence of gynecoid pelvis. RESULTS: 3D CT pelvimetry was performed on 226 women aged 23-65 years without any history of cephalopelvic disproportion and who had at least one delivery of an average fetal size (>2,500 g). The median parity was 4, and the mean (±SD) birth weight was 3,700 ± 498 g. Compared to the classical criteria, measured parameters and their combined use with the classical criteria significantly reduced the frequency of gynecoid pelvis (51.3 and 47.8%, respectively, vs. 71.6%; p = 0.001); however, there was no significant difference between the measured parameters and their combined use with classical criteria with regard to the frequencies of gynecoid pelvis (p > 0.05). CONCLUSIONS: With the use of measured parameters of 3D CT pelvimetry, the incidence of gynecoid pelvis reduces to a more acceptable level (51.3%) in accordance with obstetric knowledge. Since there is no considerable decrease with the addition of classical criteria, 3D CT pelvimetry alone has merit for determining a woman's pelvic capacity for obstetric needs after the improvement and standardization of measured parameters.

X-ray exposure in utero and school performance: a population-based study of X-ray pelvimetry.

AIM: To investigate the association between exposure to ionising radiation from pelvimetric examinations in utero and school performance. MATERIAL AND METHODS: This was a population-based cohort study comprising 46,066 children born in the county of Östergötland, Sweden, from 1980 through 1990. Through record linkage between Swedish registers, children exposed in utero to X-ray pelvimetry examination were compared to other children born in the same county during the study period, as well as to their unexposed siblings. Outcome variable was primary school grades, expressed in centiles and calculated through linear regression. RESULTS: In the univariate analysis, children exposed to X-ray pelvimetry in utero had higher school grades compared to unexposed children (point estimate 3 centiles, 95% confidence interval [CI]: 1.5 to 4.6). When sex, mother's education and income, birth order, and birth position were included in the analysis; however, the difference was reduced and the association was no longer statistically significant (PE 1.4, 95% CI: -0.1 to 2.8). Comparing exposed children with their siblings showed no statistical difference in univariate analysis or in multivariate analysis. CONCLUSION: No suggestion was found of a negative effect on school performance from in utero exposure of diagnostic X-ray pelvimetry.