The intraoperative use of a calliper predicts leg length and offset after total hip arthroplasty. Component subsidence influences the leg length.

BACKGROUND: The purpose of total hip arthroplasty (THA) post-surgery and proper physiotherapy is positive recovery for the patient. Consideration is given to hip replacement biomechanics by ensuring no discrepancies in limb length (LL) and a stable prosthesis. Therefore, the patient must have proper preoperative planning and communication and a clear understanding of what to expect. METHODS: A prospective series of 59 THA operated by a single surgeon via Hardinge approach was studied, using an intraoperative calliper (CAL) to predict the change of LL and offset. We compared the results of the intraoperative changes before and after THA implantation with the reference of these values on anteroposterior x-ray pelvis. The importance of leg length balance and a good offset restoration is questioned, and the effect of component subsidence on leg length is considered. RESULTS: The average preoperative leg length discrepancy was -6.0 mm, postoperatively +3.6 mm. There was a strong correlation between the CAL measurements and the values on the x-ray (LL, r=0.873, p<0.01; offset, r=0.542, p<0.01). Reliability is better for limb length than for offset. These results are comparable within the literature and the statistical results from other studies reviewed. In addition, we evaluate the importance of subsidence of the prosthesis components for long-term results. CONCLUSION: The intraoperative use of CAL gives excellent results in predicting the final LL and offset after THA. Considering subsidence of prosthesis components, a target zone around +5 mm might be more suitable for leg length directly postoperatively. Moreover, surgeons must discuss the topic of leg length discrepancy (LLD) intensively with the patient pre-operatively. LEVEL OF EVIDENCE: Level 4, prospective cohort study.

Pelvimetry in Squirrel Monkeys (Saimiri scireus Linnaeus, 1758) / Pelvimetria em macacos-de-cheiro (Saimiri scireus Linnaeus, 1758)

Saimiri sciureus is a neotropical primate widely used in research. However, there are still difficulties regarding their reproduction in vivaria due to the high incidence of dystocia. Dystocia in primates can be caused by cephalopelvic disproportion and in Squirrel Monkeys, pregnancy of large fetuses were reported. This paper describes pelvimetry data of adult females and subadults in specimens of Squirrel Monkeys, from a research colony of Para, Brazil. Pelvic radiographs were obtained in ventrodorsal projections and the following measurements were taken: superior bi-iliac diameter (SBID); inferior bi-iliac diameter (IBID); bi-iliac average diameter (BIAD); right diagonal diameter (RDD); left diagonal diameter (LDD); sacro-pubic diameter (SPD); Based on the obtained diameters, the entrance area of the pelvis (EAP) was also calculated. The average values of the pelvic diameters and EAP in adult females were SBID 1.714cm, BIAD 1.957cm, IBID 1.686cm, RDD 2.771cm, LDD 2.764cm, SPD 2.543cm and EAP 3.9056cm2; and subadult females: 1.588cm SBID, 1.850cm BIAD, 1.625cm IBID, 2.50cm RDD, LDD 2.474cm, 1.95cm SPD and 2.8293 cm2 EAP. Saimiri sciureus pelvis is characterized as dolichopelvic. There was statistical significance between the values for adult females and subadults to SBID, BIAD, RDD, LDD, SPD and EAP. The values of SBID and IBID were lower when compared to the published data for the same species. The result found on this paper will serve as a basis for future studies using pelvic measurements and dystocia prediction of neotropical primates and comparison between different vivaria.(AU)

Saimiri sciureus é uma espécie de primata neotropical muito utilizada como animal de pesquisa. No entanto ainda há dificuldades em biotérios quanto a sua reprodução devido à alta ocorrência de distocia. A distocia em primatas pode ter origem devido à desproporção cefalopélvica, sendo que em macacos-de-cheiro é relatada a gestação de fetos grandes. O presente trabalho descreve dados de pelvimetria em espécimes de macaco-de-cheiro, fêmeas adultas e subadultas provenientes de uma colônia de pesquisa do Pará, Brasil. Foram realizadas radiografias da pelve em projeção ventrodorsal e por meio destas mensurados os diâmetros biilíaco superior (DBIS); diâmetro biíliaco inferior (DBII); diâmetro biilíaco médio (DBIM); diâmetro diagonal direito (DDD); diâmetro diagonal esquerdo (DDE); diâmetro sacro-púbico (DSP); com base nos diâmetros obtidos também foi calculada a área de entrada da pelve (AEP). Os valores médios dos diâmetros pélvicos e da AEP em fêmeas adultas foram: DBIS 1,714cm, DBIM 1,957cm, DBII 1,686cm, DDD 2,771cm, DDE 2,764cm, DSP 2,543cm e AEP 3,9056cm2; e para fêmeas subadultas: 1,588cm DBIS, 1,850cm DBIM, 1,625cm DBII, 2,50cm DDD, 2,474cm DDE, 1,95cm DSP e 2,8293 cm2 AEP. Observou-se que a pelve de Saimiri sciureus é dolicopélvica. Houve diferença estatística significativa entre os valores para fêmeas adultas e subadultas para DBIS, DBIM, DDD, DDE, DSP e AEP. Em comparação com dados da literatura de pelvimetria para S. sciureus observaram-se menores valores de DBIS e DBII. O resultado deste trabalho servirá como base para futuros estudos utilizando-se mensurações pélvicas e predição de distocia em primatas neotropicais e referência para comparação entre S. sciureus de diferentes biotérios.(AU)

Comparative dose levels between CT-scanner and slot-scanning device (EOS system) in pregnant women pelvimetry.

PURPOSE: To estimate fetal absorbed doses for pregnant women pelvimetry, a comparative study between EOS imaging system and low-dose spiral CT-scanner was carried out. For this purpose three different studies were investigated: in vivo, in vitro and Monte Carlo calculations. METHODS: In vivo dosimetry was performed, using OSL NanoDot dosimeters, to determine the dose to the skin of twenty pregnant women. In vitro studies were established by using a cubic phantom of water, in order to estimate the out of field doses. In the latter study, OSLDs were placed at depths corresponding to the lowest, average and highest position of the uterus. Monte Carlo calculations of effective doses to high radio-sensitive organs were established, using PCXMC and CTExpo software suites for EOS imaging system and CT-scanner, respectively. RESULTS: The EOS imaging system reduces radiation exposure 4 to 8 times compared to the CT-scanner. The entrance skin doses were 74% (p-values <0.01) higher with the CT-scanner than with the EOS system. In the out of field region, the measured doses of the EOS system were reduced by 80% (p-values <0.02). Monte Carlo calculations confirmed that effective doses to organs are less accentuated for EOS than for CT pelvimetry. CONCLUSIONS: The EOS system is less irradiating than the CT exam. The out-of-field dose which is significant, is lower in the EOS than in the CT-scanner and could be reduced even further by optimizing the time used for image acquisition.

An evaluation of the EOS X-ray imaging system in pelvimetry.

OBJECTIVES: To demonstrate the reliability of the EOS imaging system in measuring the internal diameters of the bony pelvis. MATERIALS AND METHODS: A prospective study comparing the results of the pelvimetry of 18 dry pelvises carried out on the EOS imaging system to measurements taken manually and using the two current gold standard CT methods. Pelvimetric measurements of each pelvic bone were obtained using four methods and compared: direct manual measurements, spiral and sequential CT pelvimetry, and 2D-3D low-dose biplanar X-rays. The various obstetric diameters were measured to the millimetre and compared. RESULTS: There was no significant difference in the different diameters assessed, with the exception of the interspinous diameter. There was a highly significant correlation (P < 0.001) between the values measured manually and by EOS for the Magnin index (Pearson = 0.98), the obstetric conjugate diameter (Pearson = 0.99), and the median transverse diameter (Pearson = 0.87). CONCLUSION: The EOS imaging system allows for an ex vivo determination of the obstetrical diameters that is reliable enough to estimate obstetric prognosis, producing comparable measurements to CT. In view of concerns about protection from radiation, this low-dose imaging technique could become, after in vivo prospective validation, the new gold standard for pelvimetry and therefore a good alternative to CT.

[Relation between pelvis malposition and functional knee pain by long distance running]. / Zusammenhang zwischen einseitiger Beckenfehlstellung und funktionell bedingten Knieschmerzen am Beispiel des Langstreckenlaufs.

PURPOSE: During endurance run knee problems often appear. This study wants to show the connection between a one- sided malposition of the pelvis and knee joint pain during endurance running. METHOD: We tested endurance runners which had pelvis malposition and knee pain. Therefore 100 athletes were tested, 50 with knee pain and 50 without knee pain. Manual examination and clinical instruments were used for examination of sacroiliac joints for measurement of vertical distances between spinae iliacae anteriores superiores. Collected data were analyzed by appropriate statistical methods. RESULTS: The results show that there is a connection between a one- sided pelvic malposition and knee pain during endurance running. These relations are probably realized by changes in lower extremity dysfunction as a result of pathological chains. The one sided pelvis malposition was in the control group significant higher (0.9 ± 0.4 cm) than in the control group (0.3 ± 0.2 cm). CONCLUSION: There is a correlation between knee pain and os coxae malposition. (It is necessary in examine and treat the the cause- and effect chain to prevent injuries).

Estudio prospectivo, aleatorizado y controlado para evaluar la utilidad de la radiopelvimetría en la inducción de parto en primigrávidas / Prospective, randomised and controlled study to evaluate the usefulness of radiopelvimetry in induced labour in primigravidae

Introducción: Existen muy pocos estudios publicados en la literatura científica que evalúen la utilidad real de la radiopelvimetría (RPM). Las recomendaciones actuales acerca de su empleo están basadas en un único metaanálisis que incluye tan sólo 4 estudios con muy escaso nivel de evidencia científica. Objetivos: Evaluar la utilidad de la RPM en la inducción del parto en mujeres primíparas para el diagnóstico de la desproporción pélvico-cefálica y analizar su influencia en la duración del parto, la mortalidad neonatal y la tasa de cesáreas. Material y métodos: Se ha realizado un estudio observacional prospectivo, aleatorizado y doble ciego en una población de 264 gestantes primigestas en las que estaba indicada la inducción del parto. Resultados: La RPM no influye en la tasa de cesáreas ni en los resultados perinatales y presenta un valor predictivo bajo como factor pronóstico de la vía del parto (AU)

Introduction: There are very few studies published in the scientific literature to assess the real value of the x-ray pelvimetry (X-PM). The current recommendations on its use are based on a single meta-analysis that includes only four studies with a very low level of scientific evidence. Objectives: To evaluate the usefulness of the X-PM in induction in primiparous women for the diagnosis of pelvic-cephalic disproportion and analysing its influence on the duration of pregnancy, neonatal mortality and the rate of caesarean sections. Materials and methods: The observational, prospective, randomised, double-blind, study, in a population of 264 primigravid pregnant women in whom induction of labour was an indication. Results: X-ray pelvimetry did not influence the rate of caesarean section or the perinatal results, and has a low predictive value as a prognostic factor in the method of delivery (AU)

Intrinsic measurement bias on computed tomography scout view is unpredictable: Computed tomography pelvimetry using a phantom.

Our aim was to determine the degree of bias in CT scanogram measurements. We obtained standard lateral and anteroposterior (AP) pelvimetry scanograms of a phantom pelvis after placing ball bearings or aluminium rods to mark bony landmarks. Computed tomography pelvimetry was carried out at the manufacturer-recommended table height on two commercial CT scanners and at 10-mm increments up to 50 mm above and below this height. The AP inlet, AP outlet, interspinous distance and transverse diameters were each measured three times for each scanogram. The true measurements were obtained directly from the disassembled phantom. Bias was defined as the difference between the CT measurement and the true measurement. Observer error was negligible. The transverse diameter was overestimated at high table positions and underestimated at low table positions on both scanners (+6 to -10 mm). After correcting for geometric distortion, up to 6 mm bias was still present. The point at which no bias occurred was different for each scanner and did not correspond to the manufacturers' recommended table height. The outlet was overestimated on both scanners by up to 5 mm. The true inlet measurement was overestimated by 1.2 mm. The interspinous distance was minimally underestimated on both scanners. The measurements on CT scanogram were underestimated or overestimated in an inconsistent and unpredictable fashion, varying from one type of measurement to another and from CT scanner to CT scanner. This has implications for the accuracy and clinical utility of measurements obtained from a CT scanogram.

[Low dose helical CT pelvimetry: evaluation of radiation dose and image processing]. / Pelviscanner hélicoïdal en basse dose: évaluation de la dose d'irradiation et du traitement d'images.

PURPOSE: to estimate from phantom measurements the radiation dose and the accuracy of helical ct pelvimetry. MATERIALS AND METHODS: Eight helical CT acquisitions using different tube current (100, 50, 25 or 10mAs) and pitch factor (1.125 or 1.375) settings but identical collimation (2mm) and kilovoltage (120 kVp) were evaluated using a four-channel MDCT scanner and compared with conventional CT pelvimetry including a single scout and two transverse images. A plexiglas phantom combined with an ionization chamber was used to calculate the CTDIw and DLP for each acquisition. Then, an ex vivo phantom of bony pelvis was used to evaluate the accuracy of helical acquisitions for the measurement of pelvic diameters (i.e. the antero-posterior inlet, the transverse inlet and the interspinous distance). Reconstructions of helical acquisitions were performed using 2D MPR, 3D MIP and 3D SSD algorithms. RESULTS: CTDIw and DLP of conventional pelvimetry were 26 mGy and 42 mGy.cm respectively. The radiation dose of helical acquisitions decreased linearly with tube current (CTDIw: from 13 to 1.3 mGy, DLP: from 218.3 to 18.7 mGy.cm). Compared to conventional CT, the dose was nearly similar at 25 mAs and reduced at 10 mAs. Helical acquisitions provided accurate measurements of pelvic diameters with a pitch of 1.125 and a 2D MPR algorithm to evaluate the AP inlet and a 3D MIP algorithm to evaluate the transverse inlet and the interspinous distance. Variations of tube current did not influence the accuracy of pelvic diameter measurement. CONCLUSION: Our results suggest that accurate low-dose helical CT pelvimetry using 10-25 mAs and a pitch factor of 1.125 combined with 2D MPR and 3D MIP reconstructions is possible.

[Computerized tomography pelvimetry: recent advances]. / Lapelvimétrie par scanner: récentes évolutions.

We describe a new technique of pelvimetry by computerized tomography (CT), using multislice-CT. This new technique can provide measurements of the classical diameters and is able to bring new informations on anatomical aspect of the bony pelvis, especially of the superior strait, with images easier to understand by obstetricians and midwives. It is a simple technique to perform, without increasing cost. No additional irradiation is needed, but this point has to be confirmed by multicenter evaluation.

The accuracy of the Palpation Meter (PALM) for measuring pelvic crest height difference and leg length discrepancy.

STUDY DESIGN: Test-retest reliability and validity. OBJECTIVE: To determine the validity and reliability of the Palpation Meter (PALM). BACKGROUND: Leg length discrepancy (LLD) has been associated with a variety of musculoskeletal disorders. Therefore, the clinical measurement of LLD has become a routine and important part of the physical examination. The PALM is an instrument that was recently developed to indirectly measure LLD, but little is known about its measurement properties. METHODS AND MEASURES: Fifteen healthy and 15 symptomatic subjects with suspected LLD participated in this study. Measurements of pelvic crest height difference (PD) were obtained by 2 examiners using the PALM. A standing antero-posterior (AP) radiograph of each subject's pelvis was taken, and PD and LLD (femoral head height difference) were determined from the radiograph for comparison with the PALM values. Intraclass correlation coefficients (ICCs) were calculated to determine the validity and reliability estimates of the PALM. RESULTS: For all subjects, the validity estimates (ICC2,3) of the PALM for PD were excellent (0.90 for rater 1 and 0.92 for rater 2) when compared with the standing AP radiograph of the pelvis. The PALM was less accurate (ICC2,3 of 0.76 and 0.78 for rater 1 and 2, respectively) as an indirect estimate of LLD. Intrarater reliability for each rater was excellent (ICC3,3 = 0.97 and 0.98) and interrater reliability was very good (ICC2,3 = 0.88). CONCLUSION: The PALM is a reliable and valid instrument for measuring PD. Clinicians should consider this convenient, cost-effective clinical tool as an alternative to radiographic measurement of pelvic crest height difference.

An appraisal of computed tomography pelvimetry in patients with previous caesarean section.

This study was conducted to determine the value of computed tomography (CT) pelvimetry in patients with previous caesarean section. Of 219 pregnant women with one previous caesarean section, 100 had antenatal CT pelvimetry and a control group of 119 women had no CT pelvimetry. In the CT pelvimetry group, 51.0% delivered by caesarean section, 28.0% underwent elective caesarean section for contracted pelvis based on the findings of CT pelvimetry and 23% underwent emergency caesarean section after a trial labour. In the control group, 21.8% underwent emergency caesarean section. The differences in birth weight and Apgar scores between the groups were not statistically significant. CT pelvimetry increased the rate of caesarean delivery, suggesting that CT pelvimetry before a vaginal birth after a previous caesarean delivery is of limited value.

Radiation doses and image information in digital pelvimetry with a phosphorous screen.

PURPOSE: The aim of the investigation was to determine the patient dose in digital pelvimetry by means of a phosphorous screen as compared to a screen-film combination of very high sensitivity. MATERIAL AND METHODS: Entrance dose measurements and absorbed dose determinations in a series of patient exposures were made. In the first series the exposure reduction was achieved by reducing the mAs (tube current x exposure time) for the lateral and the a.p. views as compared with those used for the screen-film system. In the second series the tube potential, kV, was increased for both projections in order to increase the penetration capacity of the radiation. RESULTS AND CONCLUSION: The imaging plate technique can be used in pelvimetry with a dose reduction (and a corresponding reduction of the radiation risk to the foetus) to less than 50% of that achieved with a screen-film system of the very highest sensitivity.

CAD modeling of the birth process. Part II.

We are engaged in studying the process of human birth by developing a computer-based dynamic model that can be adapted to specific birth scenarios. The individual characteristics of a given pregnant woman and fetus, embedded in their clinical measurements and CT and MRI images, are captured in the model. One can thereby predict adverse events that might happen during labor and delivery. Based on our findings from a preliminary design and execution of this model, we believe it holds great promise as an accurate, cost-effective diagnostic and teaching tool that will help predict conditions during individual labor scenarios that might cause traumatic birth injuries, and thereby enable us to make the most informed clinical decisions possible.

[A knowledge-based system for the interpretation of pelvimetric findings]. / Ein wissensbasiertes System zur Interpretation pelvimetrischer Befunde.

Digital Image Intensifier Radiography (DIR) as well as Nuclear Magnetic Resonance Tomography (NMR) using an especially developed imaging routine for pelvimetry are suitable tools for the assessment of the anatomical conditions when mechanical problems are supposed to occur during birth (cephalopelvic disproportion, breech presentation). A concept for an optimised evaluation procedure of these imaging techniques has been developed, including: a more elaborate measuring protocol, easily and precisely executable due to appropriate software packages being implemented in the diagnostic units, calculation of obstetrically relevant parameters not deriving immediately from the imaging procedures. This is possible by means of multiple regression analysis of a data base from 467 evaluated female pelvis computed tomograms, calculation of intrapelvic soft tissue place requirements by means of correlative analysis of female computed tomograms and weight-/height-index, empirical determination of cut off values in borderline pelvi-fetometric constellations evaluating 190 births by means of logistic regression of the according pelvic-fetometric data. The calculations necessary to obtain all these parameters are implemented in a software package which also contains an algorithm for the general characterisation of an individual pelvis. Thus, a rather sophisticated knowledge base for pelvic assessment becomes easily accessible.

[Intraobserver and interobserver variation in measurement of the pelvic diameter using DeLee's internal pelvimeter in Cesarean section]. / Intra- og interobservatørvariation ved måling af conjugata vera obstetrica med DeLee's interne pelviometer ved sectio caesarea.

The method of measuring the true conjugata with DeLee's Internal Pelviometer at caesarean section was evaluated. In 58 women the true conjugata were blindly measured three times by the surgeon and also, in fifty cases, three times by the assistant. Only a slight intraobserver difference was found: median range was 0.42 cm. There was no significant interobserver variation. We conclude that DeLee's Internal Pelviometer can be used to measure the true conjugata at caesarean section, but the use of pelviometry in modern obstetrics is questioned.

[Apple-Macintosh compatible software for documentation, management and evaluation of ultrasound findings in obstetrics]. / Eine Apple-Macintosh-kompatible Software zur Dokumentation, Verwaltung und Auswertung von Sonographiebefunden in der Geburtshilfe.

The advantage of using a computer to automate routine calculations and print out charts of the obstetrical ultrasound examination is obvious. This report describes a software designed to simplify the documentation and analysis of ultrasound data in obstetrics. The system is easy to use, even for persons with little computer knowledge. The programme was written in FoxBase+/Mac (Fox Software, Inc., USA). FoxBase+/Mac takes full advantage of the easy-to-learn, easy-to-use Macintosh interface and is also very fast. Another advantage of this software is that it can be used in teaching. Non-experienced examinators can double-check the correctness of their scanning planes by observing the ultrasound pictures with the markers indicating the right measurement sites and the lists of standard values of biometrical parameters for the corresponding gestational age on the screen. In routine obstetrical ultrasound examinations it takes less than 5 min to enter the foetal biometry data and print out reports. These reports are informative and easy to interpret.

[Prevention of human birth trauma I. Computer-assisted simulation of delivery using magnetic resonance tomography and finite element analysis]. / Zur Prävention des menschlichen Geburtstraumas I. Mitteilung: Die computergestützte Simulation des Geburtsvorganges mit Hilfe der Kernspintomographie und der Finiten-Element-Analyse.

Imaging procedures suitable for diagnosis of cephalopelvic disproportion, such as radiological pelvimetry, computer- or magnetic resonance imaging (MRI) fail to reflect the dynamics of delivery, including deformations of the birth channel as well as of foetal structures. In order to validate findings of imaging procedures in this respect, a method has been developed to perform dynamic, biomechanical postprocessing of the static information obtained from MRI. Using a specially developed software MRI pixel, matrices of the maternal pelvis and the foetal head were colour-coded and--according to the principle of equal density--line data were created. After sectional attribution of the resulting polygones, a three-dimensional mesh of so called Finite Elements (FE) was created, which can then be used for deformation analysis. The foetal head was then moved through the birth channel by means of computed simulation. This allows not only ongoing deformations to be visualised, but also resulting forces can be calculated at any time of the delivery process for any point of the anatomical model. Furthermore, these calculations can be performed assuming various conditions such as different cephalopelvic dimensions and various labour forces or biomechanical properties of the tissues involved. This paper aims at presenting the method and its mode of working by means of one example of a computed birth simulation.

[Obstetric pelvimetry using nuclear magnetic resonance tomography (MRI): clinical experiences with 150 patients]. / Geburtshilfliche Beckenmessung mittels Kernspintomographie (MRI): Klinische Erfahrungen bei 150 Patientinnen.

Between Oct. 1987 and Oct. 1991 150 patients of the Frauenklinik Freiburg were examined by MR pelvimetry (MRI), 135 of which were "ante partum", i.e. just before delivery. The indications were: earlier operative or strongly protracted delivery, clinical suspicion of disproportion between head and pelvis, or obstetrical "problem pelvis" indicated by manual pelvic examination or ultrasonic foetometry. Previous experimental measurements with a phantom and the comparison with conventional radiograms by Guthmann and Martius of 10 patients in puerperium have shown, that the mean divergence was +/- 2 mm, the maximum divergence 5 mm. The MRI method for pelvimetry "ante partum" or in childbed, proved to be a method of high accuracy and a very good option to judge the pelvic shape, whilst being well accepted by the patients. Furthermore, it allows to determine the foetal BIP (biparietal head-diameter), to judge the pelvic soft-tissue, as well as the visualisation of the birth canal, all without any exposure to radiation. MR pelvimetry is thus part of today's clinical routine. The disadvantages are still the high costs as well as the fact, that only few centres have access to MRI equipment. Nevertheless, the pelvimetry "post partum" can be safely practised radiologically due to the very low radiation exposure.

[Cephalic index: a neglected parameter of standard fetal biometry]. / Der Kopfindex: ein vernachlässigter Parameter der fetalen Standardbiometrie.

From 1.1.1990 to 15.3.1991, in 1074 women between the 13th and 40th weeks of pregnancy, the biparietal diameter (BIP), fronto-occipital diameter (FOD) and kephalic index (KI = BIP/FOD) were measured. The median of the kephalic index varied between 0.81 and 0.84 during different pregnancy weeks, with a range between 0.67 and 1.00. Correction to normokephaly (KI = 0.84) produced differences of up to 10 mm to measured values of BIP. We believe it necessary to determine the kephalic index in each kephalometry and to correct the measured value of BIP at least in those cases where the measured kephalic index differs significantly from normokephaly (KI = 0.84).

A comparative study of X-ray pelvimetry and CT pelvimetry.

In this study 24 patients who had conventional erect lateral X-ray pelvimetry had a CT pelvimetry done after delivery to complete the pelvimetry views. The erect lateral pelvimetry was read independently by a Consultant Radiologist, Consultant Obstetrician and a Medical Officer training in Obstetrics and Gynaecology. Using CT pelvimetry as the 'gold standard' (as the error of measurement was known with the machine used) the 3 readings were compared. There was no statistical difference in the values suggesting that X-ray pelvimetry is comparable to CT pelvimetry. However CT pelvimetry is preferred, if available, because of the lower dose of radiation involved, more comfort for the patient and shorter time in performing the procedure. Measurements done are easily read directly from the CT console.