RESUMEN
OBJECTIVES: Fractional thigh volume (TVol) and fractional arm volume (AVol) measurements by three-dimensional (3D) ultrasound can reveal valuable information on fetal soft tissue development. However, it is not clear whether TVol or AVol provides better estimates of fetal body proportion and adiposity, independent of routine two-dimensional (2D) ultrasound biometry. The primary objective of the current study was to determine the correlations between fractional limb volumes (FLVs) and neonatal anthropometric parameters. DESIGN: In this cross-sectional study, fetal FLVs were obtained within 24 h before term delivery from 40 medically and obstetrically uncomplicated pregnancies scheduled for elective cesarean section. TVol and AVol were determined using offline software. Postnatal morphometric data including birth weight; crown-heel, arm, and leg lengths; head, abdominal, mid-thigh, and mid-arm circumferences; and anterior thigh, biceps, and subscapular skinfold thicknesses were obtained. Pearson and partial correlation analyses were used to determine the relationships across antenatal volume calculations and neonatal indices. Correlation coefficients (r) were calculated. RESULTS: Mean maternal age, BMI, and parity were 29.1 ± 5.4 years, 29.7 ± 3.5 kg/m2, and 1.0 ± 1.3, respectively. AVol showed moderate correlations with most of the neonatal parameters, including mid-thigh circumference (r = 0.683), mid-arm circumference (r = 0.627), birth weight (r = 0.583), head circumference (HC, r = 0.560), and abdominal circumference (r = 0.542). However, TVol was weakly related to only some of the indices. After controlling for gestational age, maternal age, BMI, parity, and 2D ultrasound biometry, TVol was no longer associated with any of the parameters, while AVol was independently correlated with mid-thigh (r = 0.724) and mid-arm circumference (r = 0.560), birth weight (r = 0.502), ponderal index (r = 0.402), HC (r = 0.382), biceps (r = 0.384), and subscapular skinfold thickness (r = 0.350). LIMITATIONS: The current design includes limited number of pregnancies with only scheduled cesarean deliveries. Neonatal percent body fat was not calculated, and air-displacement plethysmography was not used to assess neonatal body composition. The study population was Caucasian with a relatively high maternal BMI, which may limit extrapolation of the results to other settings. CONCLUSIONS: AVoL measurements by 3D ultrasound before delivery are significantly correlated with most of the neonatal morphometric indices, independent of maternal characteristics and 2D biometric parameters. AVol may have advantages over TVol for assessing limb soft tissue development in term fetuses. Future research can focus on feasibility and predictive ability of AVol measurements in prospective studies that include serial biometry over time.
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Antropometría/métodos , Brazo/embriología , Peso al Nacer , Muslo/embriología , Ultrasonografía Prenatal/métodos , Adulto , Brazo/diagnóstico por imagen , Composición Corporal , Cesárea , Estudios Transversales , Femenino , Desarrollo Fetal , Feto , Edad Gestacional , Humanos , Recién Nacido , Embarazo , Muslo/diagnóstico por imagen , Adulto JovenRESUMEN
OBJECTIVE: Fetal fractional limb volume has been proposed as a useful measure for quantifying fetal soft tissue development. The aim of this study was to investigate the growth of fractional arm volume (AVol) and fractional thigh volume (TVol) of fetuses with maternal gestational diabetes (GDM) compared with those of fetuses with normal glucose tolerance (NGT). We hypothesised fetal fractional limb volume would be larger in the GDM group than in the NGT group in late gestation. DESIGN: Exploratory observational study. SETTING: Saitama Municipal Hospital. SAMPLE: A total of 165 (125 NGT and 40 GDM) singleton Japanese pregnant women. METHODS: AVol and TVol were assessed between 20 and 37 weeks' gestation as cylindrical limb volumes based on 50% of the fetal humeral or femoral diaphysis length. Women were diagnosed as GDM based on the criteria of the Japan Society of Obstetrics and Gynecology. MAIN OUTCOME MEASURES: AVol and TVol were compared between women with NGT and those with GDM at each gestational age period (2-week intervals from 20 to 37 weeks' gestation). RESULTS: Overall, 287 ultrasound scans were performed (NGT group, 205 scans; GDM group, 82 scans). There was no significant difference of AVol between the groups before 32 weeks' gestation. AVol was significantly larger in the GDM group than in the NGT group after 32 weeks' gestation (P < 0.05). TVol was not statistically different between the groups across gestation. CONCLUSIONS: Detection of variations in fetal AVol may provide greater insight into understanding the origins of altered fetal body proportion in GDM. TWEETABLE ABSTRACT: AVol, but not TVol, is significantly larger in fetuses with GDM than in those with NGT after 32 weeks' gestation.
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Brazo/embriología , Diabetes Gestacional/diagnóstico por imagen , Desarrollo Fetal/fisiología , Feto/diagnóstico por imagen , Muslo/embriología , Adulto , Brazo/diagnóstico por imagen , Diáfisis/diagnóstico por imagen , Diáfisis/embriología , Femenino , Fémur/diagnóstico por imagen , Fémur/embriología , Edad Gestacional , Humanos , Húmero/diagnóstico por imagen , Húmero/embriología , Japón , Tamaño de los Órganos , Embarazo , Muslo/diagnóstico por imagen , Ultrasonografía PrenatalRESUMEN
Retinoic acid (RA) was one of the first molecules in the modern era of experimental embryology to be shown capable of generating profound effects on limb development. In this review, we focus on the earliest events of limb development and specifically on the role of RA in establishing the domain of cells that will go on to form the limb itself. Although there is some consensus on the role of RA during the earliest stages of limb formation, some controversy remains on the mechanism of RA action and the requirement for RA signaling in forming the hindlimb buds.
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Esbozos de los Miembros/embriología , Tretinoina/metabolismo , Animales , Brazo/embriología , Miembro Anterior/citología , Miembro Anterior/embriología , Miembro Anterior/metabolismo , Regulación del Desarrollo de la Expresión Génica , Humanos , Esbozos de los Miembros/citología , Esbozos de los Miembros/metabolismo , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismoRESUMEN
The anatomical variations of the proximal portion of the long head of the biceps brachii tendon (LHBT) are rarely observed in clinical practice. However, an increase in the rate of shoulder arthroscopic surgery has led to an increase in the observation of anatomical variations of this region. The aim of this work was to analyze the development of the LHBT in 23 human embryos ranging from the 6th to 8th weeks of development. The LHBT develops from the glenohumeral interzonal mesenchyme in the 6th week. By week 7, the myotendinous junction of the LHBT develops. The anlage of the LHBT is separated from that of the glenohumeral capsule during week 8. Our results suggest that the most important period for the LHBT development occurs between the 6th and 8th weeks of embryonic development. Alterations during this critical period may cause anatomical variations of the LHBT. An additional case report from our own experience is provided as Supplementary material.
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Brazo/embriología , Músculo Esquelético/embriología , Tendones/embriología , Adulto , Brazo/anatomía & histología , Femenino , Humanos , Masculino , Mesodermo/embriología , Músculo Esquelético/anatomía & histología , Embarazo , Hombro/anatomía & histología , Hombro/embriología , Tendones/anatomía & histologíaRESUMEN
OBJECTIVES: Neonatal adiposity is associated with chronic metabolic sequelae such as diabetes and obesity. Identifying fetuses at risk for excess neonatal body fat may lead to research aimed at limiting nutritional excess in the prenatal period. We sought to determine whether fetal arm and leg soft tissue measurements at 28 weeks' gestation were predictive of neonatal percent body fat METHODS : In this prospective observational cohort study of singleton term pregnancies, we performed sonography at 28 and 36 weeks' gestation, including soft tissue measurements of the fetal arm and thigh (fractional limb volume and cross-sectional area). We estimated the neonatal body composition (percent body fat) using anthropometric measurements and air displacement plethysmography. We estimated Spearman correlations between sonographic findings and percent body fat and performed modeling to predict neonatal percent body fat using maternal characteristics and sonographic findings. RESULTS: Our analysis of 44 women yielded a mean maternal age of 30 years, body mass index of 26 kg/m(2), and birth weight of 3382 g. Mean neonatal percent body fat was 8.1% by skin folds at birth and 12.2% by air displacement plethysmography 2 weeks after birth. Fractional thigh volume measurements at 28 weeks yielded the most accurate model for predicting neonatal percent body fat (R(2) = 0.697; P = .001), outperforming models that used abdominal circumference (R(2)= 0.516) and estimated fetal weight (R(2)= 0.489). CONCLUSIONS: Soft tissue measurements of the fetal thigh at 28 weeks correlated better with neonatal percent body fat than currently used sonographic measurements. After validation in a larger cohort, our models may be useful for prenatal intervention strategies aimed at the prevention of excess fetal fat accretion and, potentially, optimization of long-term metabolic health.
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Tejido Adiposo/diagnóstico por imagen , Peso Fetal/fisiología , Ultrasonografía Prenatal , Tejido Adiposo/embriología , Adulto , Brazo/diagnóstico por imagen , Brazo/embriología , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Pierna/diagnóstico por imagen , Pierna/embriología , Embarazo , Tercer Trimestre del Embarazo , Estudios ProspectivosRESUMEN
The purpose of this study was to document the reproducibility and efficiency of a semiautomated image analysis tool that rapidly provides fetal fractional limb volume measurements. Fifty pregnant women underwent 3-dimensional sonographic examinations for fractional arm and thigh volumes at a mean menstrual age of 31.3 weeks. Manual and semiautomated fractional limb volume measurements were calculated, with the semiautomated measurements calculated by novel software (5D Limb Vol; Samsung Medison, Seoul, Korea). The software applies an image transformation method based on the major axis length, minor axis length, and limb center coordinates. A transformed image is used to perform a global optimization technique for determination of an optimal limb soft tissue boundary. Bland-Altman analysis defined bias with 95% limits of agreement (LOA) between methods, and timing differences between manual versus automated methods were compared by a paired t test. Bland-Altman analysis indicated an acceptable bias with 95% LOA between the manual and semiautomated methods: mean arm volume ± SD, 1.7% ± 4.6% (95% LOA, -7.3% to 10.7%); and mean thigh volume, 0.0% ± 3.8% (95% LOA, -7.5% to 7.5%). The computer-assisted software completed measurements about 5 times faster compared to manual tracings. In conclusion, semiautomated fractional limb volume measurements are significantly faster to calculate when compared to a manual procedure. These results are reproducible and are likely to reduce operator dependency. The addition of computer-assisted fractional limb volume to standard biometry may improve the precision of estimated fetal weight by adding a soft tissue component to the weight estimation process.
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Brazo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Muslo/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Brazo/embriología , Estudios de Cohortes , Femenino , Humanos , Embarazo , Estudios Prospectivos , Reproducibilidad de los Resultados , Muslo/embriologíaRESUMEN
The pectoralis major consists of three parts: clavicular, sternocostal and abdominal. The first is usually separated from the deltoid by a deltopectoral triangular space, and often from the sternocostal part by another triangular space. The clavicular part is a new acquisition in Anthropoids, to optimize stabilization of the upper limb to the thorax thus permitting an increased limb mobility in Primates. It is synergetic with the deltoid in arm flexion and even more in adduction. This action is important in Humans, as the coracobrachialis becomes smaller in Mammals. Among non human Primates, those having cranially displaced shoulder joint show a significant clavicular origin of the pectoralis major. The clavicular origin might be necessary in flexion of the forelimb, when the humeral insertion of the muscle is on the same transverse plane as, or cranial to, the sternal manubrium. As to the blood and nerve supply, occurrence in Humans of a neuro-vascular pedicle for the clavicular part, shared with the deltoid, indicates a relatively morpho-functional independence of this part from the rest of the muscle. Under this regard, the width of the lateral pectoral nerve, which supplies the clavicular part of the muscle, may be related to a greater functional ability. Many manoeuvres for plastic and reconstructive surgery are performed by isolating the clavicular part of the pectoralis major. Indeed, this part may be considered as a true, self-standing anatomical entity. In fact, it has morphological individuality, peculiar bony attachments and functional autonomy, so that it is simply adjacent to the sternocostal part. Moreover, according to phylogenesis, this topographic relation develops secondarily, in parallel with the development of the clavicle. Therefore, it may be regarded not only as a simple part of an extrinsic muscle of the thorax, but also as an intrinsic muscle of the upper limb.
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Clavícula/anatomía & histología , Clavícula/fisiología , Músculos Pectorales/anatomía & histología , Músculos Pectorales/fisiología , Brazo/anatomía & histología , Brazo/embriología , Brazo/fisiología , Cadáver , Clavícula/embriología , Disección , Humanos , Masculino , Músculos Pectorales/embriología , Filogenia , Tórax/anatomía & histología , Tórax/embriología , Tórax/fisiologíaRESUMEN
OBJECTIVES: This study aimed to determine whether antenatal ultrasound measurements of fetal soft-tissues and liver can predict macrosomia in women with pregestational diabetes. METHODS: Fetal biometry, soft-tissue thickness (anterior abdominal wall [STAW], thigh [STT], upper arm [STA], scapular [STS]) and liver size were measured sonographically at 23, 28, 31 and 34 weeks of gestation. Large for gestational age (LGA) was defined as a birth weight greater than 90th percentile for gestational age on standard curves adjusted for maternal height and weight, parity and fetal gender. The area (±standard error) under receiver operating characteristic (AUROC) curves were also calculated. RESULTS: A total of 29 pregnant women with pregestational diabetes were included, and a total of 663 measurements taken. Fifteen neonates were LGA. There was no significant difference in fetal soft-tissue thickness at 23, 28 and 31 weeks between the LGA and non-LGA neonates. In contrast, at 34 weeks, fetal soft-tissues were significantly thicker in LGA neonates (P<0.05), but with no difference in liver surface area between the two groups. The specificity and sensitivity of 34-week ultrasonography to detect macrosomia was 78.6% and 66.7%, respectively, for abdominal circumference (AC), 71.4% and 93.3% for STT, 85.7% and 80.0% for STA, and 71.4% and 86.7% for STAW. No parameter was more powerful than the others. The best AUROC curves were found for AC (0.807), STT (0.821), STA (0.855) and STAW (0.821). CONCLUSION: Third-trimester sonographic measurements of fetal soft-tissue may help to detect macrosomia in pregnancies complicated by pregestational diabetes.
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Diabetes Gestacional/diagnóstico por imagen , Macrosomía Fetal/diagnóstico por imagen , Feto/ultraestructura , Hígado/diagnóstico por imagen , Hígado/embriología , Pared Abdominal/diagnóstico por imagen , Pared Abdominal/embriología , Adulto , Brazo/diagnóstico por imagen , Brazo/embriología , Diabetes Mellitus Tipo 1/diagnóstico por imagen , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Femenino , Humanos , Paridad , Valor Predictivo de las Pruebas , Embarazo , Tercer Trimestre del Embarazo , Curva ROC , Escápula/diagnóstico por imagen , Escápula/embriología , Muslo/diagnóstico por imagen , Muslo/embriología , Ultrasonografía PrenatalAsunto(s)
Anemia de Diamond-Blackfan/genética , Hidropesía Fetal/genética , Mutación , Proteínas Ribosómicas/genética , Anemia de Diamond-Blackfan/embriología , Anemia de Diamond-Blackfan/metabolismo , Anemia de Diamond-Blackfan/fisiopatología , Brazo/anomalías , Brazo/embriología , Codón sin Sentido , Exones , Femenino , Muerte Fetal , Retardo del Crecimiento Fetal/etiología , Heterocigoto , Humanos , Hidropesía Fetal/etiología , Hidropesía Fetal/metabolismo , Deformidades Congénitas de las Extremidades/embriología , Deformidades Congénitas de las Extremidades/etiología , Embarazo , Proteínas Ribosómicas/metabolismoRESUMEN
OBJECTIVES: To prospectively validate the use of fractional limb volume measurements for estimated fetal weight (EFW) during the second and third trimesters of pregnancy and to summarize the medical literature regarding application of fractional limb volume for fetal weight estimation. METHODS: One hundred and sixty-four women prospectively underwent three-dimensional ultrasonography within 4 days of delivery. Birth weights (BWs) ranged from 390 to 5426 g. Fetal measurements were extracted using volume datasets for biparietal diameter, abdominal circumference, femur diaphysis length, fractional arm volume and fractional thigh volume. Fractional limb volumes were manually traced from a central portion of the humerus or femur diaphysis. Mean percentage differences and SDs of the percentage differences were calculated for EFW. The proportion of newborns with EFW within 5 or 10% of BW were compared with an estimate obtained using a Hadlock formula that was modified using model coefficients from the same local population sample. RESULTS: Ultrasound scans were performed between 21.7 and 42 weeks' menstrual age. Optimal model performance (1.9 ± 6.6%) resulted from using a combination of biparietal diameter, abdominal circumference and fractional thigh volume. The precision of this model was superior to results obtained using a modified Hadlock model (1.1 ± 8.4%), although accuracy of these predictions was slightly decreased for female infants. For all fetuses, the prediction model that incorporated fractional thigh volume correctly classified a greater proportion of EFW within 5% (55.1 vs 43.7%; P = 0.03) or 10% (86.5 vs 75.9%; P < 0.05) of BW when compared with the modified Hadlock model. CONCLUSIONS: Fractional thigh volume can be added to two-dimensional sonographic measurements of the head and trunk to improve the precision of fetal weight estimation. This approach permits the inclusion of soft tissue development as part of a weight estimation procedure for the assessment of generalized fetal nutritional status.
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Brazo/embriología , Peso Fetal/fisiología , Muslo/embriología , Adulto , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Imagenología Tridimensional , Tamaño de los Órganos , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal/métodosRESUMEN
OBJECTIVE: To compare fetal upper arm and thigh volume measurements acquired by three-dimensional (3D) ultrasound using the multiplanar and the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) methods with different number of sectional planes. METHODS: This study enrolled 40 healthy pregnant women between 20 and 40 weeks of gestation. The volume of fetal limbs was calculated using the multiplanar (with 5.0 mm intervals) and the XI VOCAL (with 5, 10, 15, and 20 slice planes) methods. Comparison between the techniques was made by analysis of variance and Bonferroni statistical tests. RESULTS: Mean fetal upper arm volume measured by the 15 sectional planes XI VOCAL method was lower than the same method using 5 and 10 planes instead (pâ=â0.025 and 0.039, respectively). Fetal thigh volume showed no statistically significant differences among all studied methods. CONCLUSION: The XI VOCAL using 15 sectional planes method underestimated the fetal upper arm volume by 5 and 10 planes XI VOCAL techniques.
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Brazo/diagnóstico por imagen , Imagenología Tridimensional/métodos , Muslo/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Adulto , Anatomía Transversal/métodos , Brazo/embriología , Brazo/crecimiento & desarrollo , Estudios Transversales , Femenino , Feto/anatomía & histología , Edad Gestacional , Humanos , Tamaño de los Órganos , Embarazo , Muslo/embriología , Muslo/crecimiento & desarrollo , Adulto JovenRESUMEN
The purpose of this morphologic study is to investigate the course and the branching pattern of motor branches of musculocutaneous nerve (MCN) in human fetuses. Twenty upper limbs (10 right, 10 left) of spontaneously aborted formalin-fixed fetuses were dissected under a stereomicroscope to determine motor branches for the biceps brachii and brachialis and the communicating branches between the MCN and median nerve (MN). The MCN entered the proximal and middle part of coracobrachialis in 13/20 and 5/20 of arms, respectively, and the remaining 2/20 did not pierce coracobrachialis. The communication between MCN and MN was observed in 5/20 of the arms and detected only in the distal part of the coracobrachialis. The most frequently observed innervation is the type wherein a single branch to biceps brachii, which bifurcated for supplying the short and long heads (12/20). For the innervation of brachialis, the most frequent type was a single branch from the main trunk of the MCN (15/20). During the dissections, the distance between the acromion and the emerging point of the motor branches was measured. The mean distance between the acromion and the emerging point of the all motor branches for biceps brachii in all types of specimens was 33.8 ± 6.1% of acromion-lateral epicondyle length and for brachialis was 50.6 ± 11.5% of acromion-lateral epicondyle length. The data of the MCN variations in the human fetus may be useful for the clinicians and pediatric surgery.
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Brazo/embriología , Feto/embriología , Neuronas Motoras/citología , Músculo Esquelético/embriología , Nervio Musculocutáneo/embriología , Aborto Espontáneo , Brazo/inervación , Femenino , Desarrollo Fetal , Edad Gestacional , Humanos , Masculino , Músculo Esquelético/inervación , Nervio Musculocutáneo/citologíaRESUMEN
PURPOSE: To assess the value of fetal soft tissue volume (STV) of the upper arm in predicting small-for-gestational-age (SGA) fetuses using three-dimensional (3D) ultrasound (US). METHODS: We used 3D US to test the accuracy of fetal STV of the upper arm measurement in predicting SGA in a prospective cross-sectional study. RESULTS: Fetal STV of the upper arm assessed by 3D US can differentiate SGA fetuses from appropriate-for-gestational-age (AGA) fetuses. Using the 5th percentile as the cutoff, the sensitivity of fetal upper arm STV in predicting SGA fetuses was 84.1%, specificity, 93.4%, positive predictive value, 71.1%, negative predictive value, 96.8%, and overall accuracy, 91.9%. In addition, the diagnostic accuracy of fetal arm STV was better than that of the biparietal diameter, abdominal circumference, and femur length. CONCLUSION: Fetal STV of upper arm assessment by 3D US is a novel method to predict SGA fetuses.
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Brazo/diagnóstico por imagen , Brazo/embriología , Retardo del Crecimiento Fetal/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Estudios Transversales , Femenino , Humanos , Imagenología Tridimensional/métodos , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Curva ROC , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadAsunto(s)
Brazo/embriología , Animales , Brazo/crecimiento & desarrollo , Hormonas/fisiología , HumanosRESUMEN
OBJECTIVES: The main goal of this study was to determine the accuracy and precision of new fetal weight estimation models, based on fractional limb volume and conventional two-dimensional (2D) sonographic measurements during the second and third trimesters of pregnancy. METHODS: A prospective cross-sectional study of 271 fetuses was performed using three-dimensional ultrasonography to extract standard measurements-biparietal diameter (BPD), abdominal circumference (AC) and femoral diaphysis length (FDL)-plus fractional arm volume (AVol) and fractional thigh volume (TVol) within 4 days of delivery. Weighted multiple linear regression analysis was used to develop 'modified Hadlock' models and new models using transformed predictors that included soft tissue parameters for estimating birth weight. Estimated and observed birth weights were compared using mean percent difference (systematic weight estimation error) and the SD of the percent differences (random weight estimation error). The proportion of newborns with estimated birth weight within 5 or 10% of actual birth weight were compared using McNemar's test. RESULTS: Birth weights in the study group ranged from 235 to 5790 g, with equal proportions of male and female infants. Six new fetal weight estimation models were compared with the results for modified Hadlock models with sample-specific coefficients. All the new models were very accurate, with mean percent differences that were not significantly different from zero. Model 3 (which used the natural logarithms of BPD, AC and AVol) and Model 6 (which used the natural logarithms of BPD, AC and TVol) provided the most precise weight estimations (random error = 6.6% of actual birth weight) as compared with 8.5% for the best original Hadlock model and 7.6% for a modified Hadlock model using sample-specific coefficients. Model 5 (which used the natural logarithms of AC and TVol) classified an additional 9.1% and 8.3% of the fetuses within 5% and 10% of actual birth weight and Model 6 classified an additional 7.3% and 4.1% of infants within 5% and 10% of actual birth weight. CONCLUSION: The precision of fetal weight estimation can be improved by adding fractional limb volume measurements to conventional 2D biometry. New models that consider fractional limb volume may offer novel insight into the contribution of soft tissue development to weight estimation.
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Brazo/diagnóstico por imagen , Desarrollo Fetal , Peso Fetal/fisiología , Adulto , Brazo/embriología , Biometría , Peso al Nacer , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Muslo/diagnóstico por imagen , Muslo/embriología , Ultrasonografía Prenatal/métodosRESUMEN
A paper published in 1925 reported that human fetuses with anencephaly have arms that are longer than normal. This finding was accepted as true through the early 1990s. An analysis of body dimensions done in 1996 and enlarged and updated here shows that the arms of human fetuses with anencephaly are appropriate for gestational age and normal in proportion to their leg lengths. A subtle difference in measurement technique was found to explain the discordant findings.
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Anencefalia/patología , Brazo/anomalías , Brazo/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Anencefalia/diagnóstico por imagen , Brazo/embriología , Femenino , Feto/anomalías , Feto/anatomía & histología , Feto/embriología , Humanos , Pierna/anomalías , Pierna/diagnóstico por imagen , Pierna/embriología , Embarazo , Diagnóstico PrenatalRESUMEN
Both brachialis and biceps brachii are primary flexors of the arm and elbow from the biomechanical perspective. Numerous reports exist in anatomical literature regarding accessory heads of biceps brachii, although such accessory bellies in relation to brachialis muscle are less frequently elucidated. We report a unilateral case of a rare accessory muscle interposed between the biceps brachii and brachialis, having the musculocutaneous nerve (MCN) entrapped between the two. Furthermore, the muscle divided into two slips, upper slip was attached to biceps brachii and the other gained insertion to the brachial fascia. Innervation to this accessory muscle was derived from MCN. The embryological basis for such supernumerary muscle is discussed. Additionally, the case is considered under surgical and clinical perspective, highlighting the importance of familiarity with such variations. Anatomical variations of the brachial musculature may cause diagnostic perplexities while interpreting MRI or CT scans.
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Músculo Esquelético/anomalías , Nervio Musculocutáneo/patología , Síndromes de Compresión Nerviosa/patología , Brazo/embriología , Cadáver , Humanos , Músculo Esquelético/embriologíaRESUMEN
OBJECTIVES: The main goals were to provide normal reference ranges for fractional limb volume as a new index of generalized fetal nutritional status, to evaluate the reproducibility of fractional fetal limb volume measurements during the second and third trimesters of pregnancy, and to demonstrate technical considerations for this technique. METHODS: This was a prospective, cross-sectional study of gravid women during mid to late pregnancy. Fractional limb volumes were based on either 50% of humeral or femoral diaphysis length. Each partial volume was subdivided into five equidistant slices that were centered along the mid-arm or mid-thigh. Slices were traced manually to obtain fractional arm (AVol) or fractional thigh (TVol) volume. Reproducibility studies were performed, using Bland-Altman plots, to assess blinded interobserver and intraobserver measurement bias and agreement. Selected images were chosen to demonstrate technical factors for the acquisition and analysis of these parameters. Reference charts were established to describe normal ranges for AVol and TVol. RESULTS: Three hundred and eighty-seven subjects were scanned to include 380 AVol (range, 1.1-68.3 mL) and 378 TVol (range 2.0-163.2 mL) measurements between 18.0 and 42.1 weeks' menstrual age. No gender differences were found in these soft tissue measurements (AVol, P = 0.90; TVol, P = 0.91; Mann-Whitney test). Intraobserver mean bias +/- SD and 95% limits of agreement (LOA) for fractional limb volumes were: 2.2 +/- 4.2% (95% LOA, - 6.0 to 10.5%) for AVol and 2.0 +/- 4.2% (95% LOA, - 6.3 to 10.3%) for TVol. Interobserver bias and agreement were - 1.9 +/- 4.9% (95% LOA, - 11.6 to 7.8%) for AVol and - 2.0 +/- 5.4% (95% LOA, - 12.5 to 8.6%) for TVol. Technical factors were related to image optimization, transducer pressure, fetal movement, soft tissue compression and amniotic fluid volume. CONCLUSIONS: Fractional limb volume assessment may improve the detection and monitoring of malnourished fetuses because this soft tissue parameter can be obtained quickly and reproducibly during mid to late pregnancy. Careful attention should be placed on technical factors that can potentially affect optimal acquisition and analysis of these volume measurements.
Asunto(s)
Brazo/diagnóstico por imagen , Composición Corporal , Desarrollo Fetal , Muslo/diagnóstico por imagen , Adulto , Antropometría/métodos , Brazo/anatomía & histología , Brazo/embriología , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Variaciones Dependientes del Observador , Embarazo , Valores de Referencia , Reproducibilidad de los Resultados , Muslo/anatomía & histología , Muslo/embriología , Ultrasonografía Prenatal/métodosRESUMEN
PURPOSE: to evaluate the accuracy of fetal upper arm volume, using three-dimensional ultrasound (3DUS), in the prediction of birth weight. METHODS: this prospective cross-sectional study involved 25 pregnancies without structural or chromosomal anomalies. Bidimensional parameters (biparietal diameter, abdominal circumference and femur length) and the 3DUS fetal upper arm volume were obtained in the last 48 hours before delivery. The multiplanar method, using multiple sequential planes with 5.0-mm intervals, was used to calculate fetal upper arm volume. Polynomial regressions were used to determine the best equation in the prediction of fetal weight. The accuracy of this new formula was compared with Shepard's and Hadlock's formulas. RESULTS: fetal upper arm volume was strongly correlated to birth weight (r=0.83; p<0.005). Linear regression was the best equation [birth weight=681.59 + 43.23 x fetal upper arm volume]. The fetal upper arm volume mean error (0 g), mean absolute error (196.6 g) and mean percent absolute error (6.5%) were lower than using Shepard's formula; however, the difference did not reach significance (p>0.05). Birth weight predicted by fetal upper arm volume had a mean error lower than Hadlock's formula, but this difference was not statistically significant (p>0.05). CONCLUSIONS: the accuracy of fetal upper arm volume obtained through 3DUS is similar to the accuracy of bidimensional ultrasound in the prediction of birth weight. These findings need to be confirmed by larger studies.
Asunto(s)
Brazo/diagnóstico por imagen , Brazo/embriología , Peso al Nacer , Imagenología Tridimensional , Ultrasonografía Prenatal/métodos , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Adulto JovenRESUMEN
LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Describe the terminology and classification of congenital hand anomalies. 2. Describe the incidence and embryogenesis of some common congenital hand anomalies. 3. Discuss the general principles and goals for treatment of congenital hand anomalies. 4. Describe the management of five of the more common congenital hand anomalies (syndactyly, short digits, thumb duplication, hypoplastic thumb, and radial dysplasia). SUMMARY: Congenital hand anomalies can cause substantial emotional and functional problems. This article reviews the etiology, classification, and management of some of the more common hand anomalies. A general approach to the patient and the goals of treatment are reviewed, as is the approach to five specific congenital hand anomalies: syndactyly, short digits, thumb duplication, hypoplastic thumb, and radial dysplasia.