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Background: The sternum exhibits unique anatomical variations with major clinical and forensic implications. This study is devoted to providing baseline epidemiological information about the sternal foramen and variant xiphoid morphology in Ethiopia. Two extremely interesting and unusual variations of the sternal foramen are also discussed. Methods: This observational study was carried out using dried adult human sternum obtained from skeletal remains samples brought for medicolegal examination over a period of 4 years. A total of 94 dried adult human sternums (66 males (70.2%) and 28 females (29.8%)) were obtained with an age range of 21 to 57 years and a mean age at death of 38.383 ± 11.3480 years. Dried human sternum specimens were morphologically examined, and morphometric parameters were recorded and photographed. Results: A sternal foramen was found in 18 specimens (19.1%); 17 were male and one was female. A single sternal foramen was observed in 83.3% (n=15/18) of the sternal bodies and 11.1% (n=2/18) of the xiphoid processes (both males). In addition, a double sternal foramen was observed in a single male specimen on the mesosternum and xiphoid process. The most common sternal foramen site was at the fifth costochondral junction level. The xiphoid process was present in 77 samples and ended as a single process in 83.1% (n=64/77) of samples. In 15.6% (n=12/77) of the samples, the xiphoid process was bifurcated and trifurcated in a single male (1.3%) specimen. Conclusions: The sternal foramen and variation in xiphoid morphology are common anatomical variations in Ethiopia. The findings of the current study highlight the necessity of strict precautionary measures during sternal procedures in this study population. In addition, such incidental findings during radiologic and autopsy procedures should be properly evaluated to avoid misdiagnosis and misinterpretation of such findings as traumatic or pathologic conditions., Competing Interests: No competing interests were disclosed., (Copyright: © 2023 Lema AS.)

Anatomy of the first flying feathered dinosaurs, modern birds and crocodylians, proposes an ancestral flight system divided between shoulder and chest muscles, before the upstroke muscles migrated beneath the body. This ancestral flight system featured the dorsally positioned deltoids and supracoracoideus controlling the upstroke and the chest-bound pectoralis controlling the downstroke. Preserved soft anatomy is needed to contextualize the origin of the modern flight system, but this has remained elusive. Here we reveal the soft anatomy of the earliest theropod flyers preserved as residual skin chemistry covering the body and delimiting its margins. These data provide preserved soft anatomy that independently validate the ancestral theropod flight system. The heavily constructed shoulder and more weakly constructed chest in the early pygostylian Confuciusornis indicated by a preserved body profile, proposes the first upstroke-enhanced flight stroke. Slender ventral body profiles in the early-diverging birds Archaeopteryx and Anchiornis suggest habitual use of the pectoralis could not maintain the sternum through bone functional adaptations. Increased wing-assisted terrestrial locomotion potentially accelerated sternum loss through higher breathing requirements. Lower expected downstroke requirements in the early thermal soarer Sapeornis could have driven sternum loss through bone functional adaption, possibly encouraged by the higher breathing demands of a Confuciusornis -like upstroke. Both factors are supported by a slender ventral body profile. These data validate the ancestral shoulder/chest flight system and provide insights into novel upstroke-enhanced flight strokes and early sternum loss, filling important gaps in our understanding of the appearance of modern flight.

The sternum is a stabilizing element in the axial skeleton of most tetrapods, closely linked with the function of the pectoral girdle of the appendicular skeleton. Modern mammals have a distinctive sternum characterized by multiple ossified segments, the origins of which are poorly understood. Although the evolution of the pectoral girdle has been extensively studied in early members of the mammalian total group (Synapsida), only limited data exist for the sternum. Ancestrally, synapsids exhibit a single sternal element and previously the earliest report of a segmental sternum in non-mammalian synapsids was in the Middle Triassic cynodont Diademodon tetragonus. Here, we describe the well-preserved sternum of a gorgonopsian, a group of sabre-toothed synapsids from the Permian. It represents an ossified, multipartite element resembling the mammalian condition. This discovery pulls back the origin of the distinctive "mammalian" sternum to the base of Theriodontia, significantly extending the temporal range of this morphology. Through a review of sternal morphology across Synapsida, we reconstruct the evolutionary history of this structure. Furthermore, we explore its role in the evolution of mammalian posture, gait, and ventilation through progressive regionalization of the postcranium as well as the posteriorization of musculature associated with mammalian breathing., (© 2022. The Author(s).)

Abstract: There is a paucity of osteometric standards for sex estimation from unknown skeletal remains in Jordan and the sexual dimorphism of the sternum has not yet been investigated. The aim of this study was to evaluate the sexual dimorphism in sternal measurements using 3D multidetector computed tomography (MDCT), and to assess their reliability for sex estimation in a Jordanian population. A total of 600 MDCT scans (300 males and 300 females) were used and a total of 8 sternal measurements were studied (manubrium length, sternal body length, combined length of manubrium and body, corpus sterni width at 1st and 3rd sternebrae, sternal index and area). Sexual dimorphism was evaluated by means of discriminant function analyses. Significant sexual dimorphism was found mainly in middle-aged and older adults. Including all subjects, multivariate, and stepwise functions gave an overall accuracy of 83.0% and 84.0%, respectively. Additionally, multivariate and stepwise analyses were conducted separately for each age group. The accuracy of sex estimation in multivariate analysis (all variables) varied from 63.2% in the young, and 83.7% in the middle adults to 84.9% for older adults. In stepwise analysis, the highest accuracy rates were provided by only sternal area in young adults (81.6%), and sternal area combined with sternal body length in middle-aged and older adults (84.2% and 85.3%, respectively). The best sex discriminator using univariate analysis (single variable) was sternal area followed by sternal body length (84.0% and 80.8% respectively). Notably, univariate analyses for most variables gave relatively higher classification accuracies in females but were poor at predicting males in the sample (sex bias ranged between -6.4% and -20%). Our data suggest that dimorphism in the human sternum increases with advancing age and separate discriminant functions are needed for each age group in Jordanians. In addition, multivariate and stepwise analyses using sternum gave higher classification accuracies with comparatively lower sex biases compared to univariate analyses., Competing Interests: The authors have no conflicts of interests to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The origin of powered avian flight was a locomotor innovation that expanded the ecological potential of maniraptoran dinosaurs, leading to remarkable variation in modern birds (Neornithes). The avian sternum is the anchor for the major flight muscles and, despite varying widely in morphology, has not been extensively studied from evolutionary or functional perspectives. We quantify sternal variation across a broad phylogenetic scope of birds using 3D geometric morphometrics methods. Using this comprehensive dataset, we apply phylogenetically informed regression approaches to test hypotheses of sternum size allometry and the correlation of sternal shape with both size and locomotory capabilities, including flightlessness and the highly varying flight and swimming styles of Neornithes., Results: We find evidence for isometry of sternal size relative to body mass and document significant allometry of sternal shape alongside important correlations with locomotory capability, reflecting the effects of both body shape and musculoskeletal variation. Among these, we show that a large sternum with a deep or cranially projected sternal keel is necessary for powered flight in modern birds, that deeper sternal keels are correlated with slower but stronger flight, robust caudal sternal borders are associated with faster flapping styles, and that narrower sterna are associated with running abilities. Correlations between shape and locomotion are significant but show weak explanatory power, indicating that although sternal shape is broadly associated with locomotory ecology, other unexplored factors are also important., Conclusions: These results display the ecological importance of the avian sternum for flight and locomotion by providing a novel understanding of sternum form and function in Neornithes. Our study lays the groundwork for estimating the locomotory abilities of paravian dinosaurs, the ancestors to Neornithes, by highlighting the importance of this critical element for avian flight, and will be useful for future work on the origin of flight along the dinosaur-bird lineage., (© 2021. The Author(s).)

We evaluated the applicability of the neck and sternal notch (SN) as anatomical landmarks for paediatric chest compression (CC) depth using chest computed tomography. The external anteroposterior diameter (EAPD) of the neck and chest at the SN level, mid-point between two landmarks (mid-landmark), and EAPD of the chest at the lower half of the sternum (EDLH) were measured. To estimate the depths of the landmarks from a virtual point at the same height as the position for CC, we calculated the differences between the EAPDs of the neck, SN, mid-landmark, and EDLH. We analysed the relationship between the depths of the landmarks and one-third EDLH using Bland-Altman plots. In all, 506 paediatric patients aged 1-9 years were enrolled. The depths of the neck, SN, and mid-landmark were 53.7 ± 10.0, 37.8 ± 8.5, and 45.8 ± 9.0 mm, respectively. The mean one-third EDLH was 46.8 ± 7.0 mm. The means of the differences between the depths of the neck and one-third EDLH, depths of the SN and one-third EDLH, and depths of the mid-landmark and one-third EDLH were 9.0, -6.9, and 1.0 mm, respectively. The SN and neck are inappropriate landmarks to guide compression depth in paediatric CPR.

In addition to the pelvis, cranium and phalanges, the sternum is also used for postmortem sex identification. Bone measurements may be obtained on cadaveric bones. Alternatively, computerized tomography may be used to obtain measurements close to the original ones. Moreover, usage of artificial neural networks (ANNs) in the field of medicine has started to provide new horizons. In this study, we aimed to identify sex by an ANN using lengths of manubrium sterni (MSL), corpus sterni (CSL) and processus xiphoideus (XPL) and sternal angle (SA) from computerized tomography (CT) images brought to an orthogonal plane. This study used the thin-slice thoracic CT images of 422 cases (213 female, 209 male) with an age range of 27-60 years brought to the orthogonal plane. Measurements of MSL, CSL, XPL and SA were analyzed with a multilayer artificial neural network that used stochastic gradient descent (SGD) for optimization and two hidden layers. MSL, CSL and XPL were longer, and SA was wider in men (MSL p = 0.000, CSL p = 0.000, XPL p = 0.000, SA p = 0.02). In the case of the two hidden layers of the network with 20 and 14 neurons in the hidden layers, respectively, learning rate of 0.1 and momentum coefficient of 0.9, the accuracy (Acc) of sex prediction was 0.906. In order to define a more realistic performance of the network, bootstrap was run with the confidence interval of 94%. A sensitivity (Sen) value of 0.91 and a specificity (Spe) value of 0.90 were calculated. The success rates that were achieved in sex identification with measurements on the skeleton using ANN were observed to be higher than those achieved by linear models. Also, sometimes all parts of the bones may not be found or might be deformed. In this case, the number of parameters used for the estimation will be incomplete. The ANN has the strong advantage to be able to estimate despite the missing parameter., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Preoperative airway evaluation in children is an important part of routine preanesthetic evaluation before surgery. External airway measurements, viz., thyromental, mentohyoid, and sternomental distances, while being growth dependent, could identify pediatric patients with potentially difficult airways., Objectives: This study was conducted to validate the age- and height-based formulae, derived from a previous study conducted in our institute, to predict thyromental distance, sternomental distance, and mentohyoid distance in relation with the height and age of pediatric patients., Design: Prospective cross-sectional single arm observational study., Setting: Tertiary level university teaching hospital from July 2015 to December 2016., Patients: Children (202) in the age group of 3-15 years with no obvious external airway anomaly scheduled for elective surgery under general anesthesia., Outcomes Measured: The thyromental, mentohyoid, and sternomental distances were measured preoperatively. The same parameters were then calculated based on age- and height-related formulae derived in the earlier study., Results: Bland-Altman analysis of the sample patients showed a mean difference (bias) between measured and calculated values ranging from 0.14 to -0.60 (3 - 13%). Overall agreement in terms of bias were found to be more with height-based equation for mentohyoid distance and thyromental distance and age-based equation for sternomental distance., Conclusion: Our study validates the formulae derived in the earlier study to predict thyromental, mentohyoid, and sternomental distances in children with no obvious external airway anomalies. Further studies are needed to extend the applicability of these formulae in obese children and those with craniofacial anomalies coming for general anesthesia and surgery., Competing Interests: There are no conflicts of interest.

Aim: To determine the sexual dimorphism of the sternum with standard measurements in a contemporary Croatian population sample using multi-slice computed tomography (MSCT) and to compare the data obtained by an automatic with those obtained by a manual approach., Methods: Five sternal measurements were obtained from MSCT images of 73 men and 55 women and three sternal indices were calculated. Custom image analysis software was developed for automatic segmentation and calculation of sternal measurements. Measurements of sexual dimorphism were automatically calculated and compared with manual measurements., Results: All of the sternal measurements exhibited significant differences between men and women. The discrepancies between manual and automatic measurements ranged from 2.8% to 3.6% of the mean average values obtained with the automatic approach. The most accurate single-variable discriminant function was sternal body length (82.8%), the most accurate index was sternal area (89.1%), and the discriminant function using three variables was manubrium width, sternal body length, and sternal body width (90.6%)., Conclusion: Sternal measurements are a reliable sex indicator and can be used in forensic casework. Computer-aided measurement methods can accelerate sex estimation and improve its precision and accuracy.

Keel bone damage may be painful to birds and affect their production. In order to better understand the frequency, position, and timepoint of keel bone damage that occur during production, the integrity of W-36 laying hen keel bones housed in enriched colony cages at 748.4 cm2 (116 in2) was evaluated. At four time points, 120 birds (10 per cage; three cages per each of four rooms) had keel bones evaluated. Each hen was placed in a motion limiting restraint, scanned using computed tomography (CT), fitted in vests containing tri-axial accelerometers, and placed back in their cages for 21 d. After 21 d, the hens were rescanned and returned to their cages. This process was repeated after 133 d. The CT scans were imported into Mimics analysis software (Materialise, Plymouth, MI, USA); 3D models were made of each keel bone at each time point and exported to 3-matic analysis software (Materialise, Plymouth, MI, USA). Each laying hen's keel bone model was superimposed onto scans from multiple time points resulting in four bone pairings representative of each 21-d period, the 133-d period, and the entire duration of the project. Next, the proximal portion of each bone pairing was edited to normalize bone shape according to a strict protocol. Additionally, each pairing was divided into three portions: distal aspect (3 cm), proximal aspect (2 cm), and middle portion (remaining). Whole bone pairing and each bone portion was analyzed using the Part Comparison tool in 3-matic. Raw data were compiled into three datasets and analyzed in SAS 9.3 using the GLIMMIX procedure using a three-level random intercept model. The model controlled for time, part, part(time), and system with random intercepts of bird(cage) and cage. Overall, results revealed that the greatest morphological changes occurred during the first 21-d period with regards to time (P = 0.03) and in the distal aspect of the keel with regards to part (P < 0.0001)., (© 2018 Poultry Science Association Inc.)

Identification of deceased with unclear identity is a common problem in forensic science, whereby radiologic comparison can be applied as method for identification. As this comparison is mostly made on a visual basis, it is highly dependent on the examiner and often lacks standardized procedures and statistical support. The aim of this study therefore was to develop a reproducible and examiner independent method for radiologic identification (RADid) based on morphometric and morphological features of sternal bone computed tomography (CT). Furthermore, the feasibility of an automated comparison of a post-mortem (PM) case against a database of ante-mortem (AM) cases was evaluated. 44 in situ PM CT scans of sternal bone and their corresponding AM CT scans were analysed and reproducible features were selected based on intra- and interrater reliability assessments. The selected features were further tested by contrasting AM and PM data. Moreover, an automated identity evaluation was developed by calculating the number of matching features between each PM case and an AM database consisting of 94 cases including the 44 with corresponding PM scans. Several features showed to be reliable according to their resulting correlation coefficient values (greater or equal to 0.60). The suitability and stability of these features was confirmed by contrasting AM and PM CT scans. Finally, the automated comparison was successful in 76.7% of the cases, whereby an unambiguous identification was possible in 65.1%. The present study reflects the benefits of a standardized and statistically established identification method and demonstrates the high potential of the sternal bone as a suitable structure for RADid., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The sternum as an important part of the skeleton and not only provides a crucial attachment site for the pectoral muscles and protects internal organs such as the heart and lungs for meat duck, but may also be considered as the primary ventilator in the avian respiratory system. Therefore, this study focuses on the sternum growth and mineralization kinetics of ducks from 35 d to 63 d of age. A total of 72 one-d-old males and 72 females were chosen and fed with the same diet until the age of 9 weeks. The sternum and serum were harvested at 35 d, 42 d, 49 d, 56d, and 63 d of feeding. Results showed that the sternum width rapidly grew from 35 d to 42 d and the value changed little after 42 d, while the keel length and the sternum depth did not significantly change until 49 d age. The sternum defatted weight and density increased assumed to "S" with ducks' age and their plateau in the 56 d. The sternum ash content, calcium (Ca), and phosphate (P) levels increased with duck age, then all three reached a plateau in 49 days. Similarly, serum alkaline phosphatase (ALP) activity was higher in the ducks at both 35 and 42 days, followed by 49 days, and the value was lowered to a minimum on both days 56 and 63. Conversely, serum tartrate resistant acid phosphatase (TRAP) activity substantially increased until 49 days irrespective of duck gender. Results indicate that the dimensions of the sternum were already at the maximum in 49-day-old ducks and the sternum of the ducks rapidly mineralized from 42 d to 49 d of age and achieved a plateau phase after 49-days resulting from the high activity of ALP at the sternum early mineralization., (© 2017 Poultry Science Association Inc.)

Introduction: Various screening tests are done for predicting difficult laryngoscopy with variable diagnostic accuracy. Difficult laryngoscopy is being considered a surrogate indicator of difficult intubation, though it is not the exact measure of intubation difficulty. Our objectives were to find out the better predictor of difficult laryngoscopy amongst the routinely used tests and also to find the ability of difficult laryngoscopy to predict difficult intubation., Methods: This prospective, observational study involved 314, ASA I/II adult patients requiring endotracheal intubation. Measurement of sternomental, thyromental and inter-incisor distances and gradings of mandibular protrusion and modified Mallampati were done. Statistical values including sensitivity and specificity of these tests were calculated to find the better predictor of difficult laryngoscopy. Cormack and Lehane laryngoscopy grade III/IV was defined as difficult laryngoscopy. Requirement of >3 attempts for endotracheal intubation was defined as difficult intubation., Results: The sensitivity of the Modified Mallampatti Test for predicting difficult laryngoscopy was highest, 83% compared to other tests. Total 12 (3.8%) patients had difficult laryngoscopy. Intubation was difficult in 7 (2.2%) patients, of which four had difficult laryngoscopy (P<0.001)., Conclusions: Modified Mallampati test was better for predicting difficult laryngoscopy compared to other bedside screening tests. Difficult laryngoscop could significantly predict difficult intubation in our patients.

"Broiler-type" chickens are fast-grow-ing, heavy-bodied birds with high demands on bone quality. Phenamil increased mineralization in cultured murine mesenchymal stem cells. Phenamil effects were tested in 2 groups of weight and gender matched day-old broiler chickens (n = 13). Oral administration of 30 mg phenamil/kg body weight d 1 to 13 reduced growth of chicks d 5 to 14 (P = 0.002); with phenamil-treated (PT) chick body weight being 84% of vehicle-treated (VT) chicks' body weight on d 14. Tissues collected on d 15 showed that femur lengths and widths did not differ, but tibias from PT chicks were 6% shorter (P = 0.002) and 13% narrower (P = 0.012) with 18% thinner tibial cross-sections (P < 0.008) than in VT chicks. Angles of the caudal aspect of the anterior surface of keeled-sternums were 166° in PT chicks, flatter than the 148° found in VT chicks (P = 0.000). Total mineral content of both tibia and femur were lower in PT chicks (P = 0.005 for both). Bone Ca, P, and Mg (ppm) in ash were similar, but Ca:P was lower (1.70 vs 1.75) in PT versus VT chicks (P < 0.05). Osteocalcin was ∼20% lower (P = 0.020), PINP was ∼45% higher (P = 0.000) in PT chicks. Carboxy-terminal telopeptide type I collagen (ICTP) and cross-linked N-telopeptide of type I collagen (NTX1) were similar in the 2 groups. Phenamil had unexpected and detrimental effects on bone formation in growing broiler chicks, reducing linear skeletal growth and markedly changing bone architecture., (© 2017 Poultry Science Association Inc.)

Background: Patients undergoing coronary artery bypass graft (CABG) procedures have higher incidence of difficult laryngoscopy and intubation than general surgery population. Accurate prediction of difficult laryngoscopy in CABG patients is desirable to reduce the hemodynamic response and myocardial oxygen requirements. Recently, thyromental height test (TMHT) has been proposed as one of the highly sensitive and specific bedside tests to predict difficult airway. We, in our prospective observational study, evaluated the accuracy of the TMHT in predicting difficult laryngoscopy., Methodology: A total of 345 patients undergoing CABG of either sex, in the age group of 35-80 years, American Society of Anesthesiologists 111, undergoing CABG, were studied. Airway assessment was performed with modified Mallampati test with the addition of thyromental distance, sternomental distance, and TMHT. Intraoperatively, direct laryngoscopy was done in accordance with Cormack and Lehane grade of laryngoscopy. The preoperative data and laryngoscopic findings were used together to evaluate the accuracy of TMHT. The sensitivity, specificity, positive and negative predictive values of other three tests were calculated according to standard formula., Results: A total of 345 patients were in the group with mean age of study population at 56.7 (standard deviation 9.1) years (35-80 years). This study showed that almost all tests had good specificity, but sensitivity was poor. However, sensitivity of TMHT was 75% with accuracy of 95%. Receiver operating characteristic curve analysis of TMHT-derived cutoff was 52.17 which increased sensitivity to 81.25% and specificity to 92.3%., Conclusion: TMHT had a higher sensitivity compared to other tests along with good positive and negative predictive value and a very high specificity.

Aim of the Study:: Methods based on the positive linear relationship existing between stature and long bones are most commonly used to estimate living stature in forensic anthropology. The length of the sternum and its parts has been advanced as a plausible alternative to estimate stature when such long bones are missing or damaged., Material and Methods: This meta-analysis aims to quantify evidence on the correlation between the sternum/sternal parts length and stature. Nine studies were included with 1118 sternal bones., Results: Analyses showed that the length of the meso-sternum (manubrium + body) yielded the best correlation with stature; 53.5% and 55.42% for men and women, respectively. The second best variable is the total sternal length with correlations of 44.3% and 55% for men and women, respectively. Subgroup analysis of autopsy studies demonstrated even a higher correlation of 58.2% for the meso-sternal length. Manubrium and body lengths showed the least correlation values. Except for the body length, females exhibit a better correlation than man between all other sternal lengths and stature., Conclusions: While the meso-sternal length is found to be the most correlated variable with stature, all sternal lengths are to be considered with caution when estimating stature. The relatively low values of the weighted correlation results should raise the question of reliability and limit the use of sternal length when long bones are available. Future research using larger samples from different populations and taking into account the fusion status of the sternum are needed.

The intubation difficulties in obese patients are not a new problem. They may result from an accumulation of fat in the oral cavity and cheeks. A thick tongue is also a significant factor. The literature reports that some tests to determine the intubation difficulties in obese people may be unreliable. The observed predictors of difficult intubation were the thyromental and sternomental distance and the intubation difficulty scale: FRONT score.The aim of this study was to assess the degree of difficult intubation in obese patients by the parameters such as the thyromental and sternomental distance. The authors also tried to evaluate the frequency of the guidewire usage and the number of intubation attempts in obese patients in the research sample.The study included the group of 153 patients intubated in prehospital conditions. The research was conducted in 3 clinical centers receiving patients from prehospital care. Among the members of the research sample, obese patients with body mass index >35 were selected and evaluated for various predictors of intubation difficulties. Quantitative analysis of differences in the incidence of the variables was assessed using the chi-squared test for P < 0.05. Analyses were performed in STATISTICA.Complications such as postintubation hematomas were more frequent in obese patients of the research sample. The frequency of the guidewire usage observed in that group was also higher. As anticipated by the adopted predictors, most of the obese patients were classified as difficult to intubate.There is a correlation between the occurrence of injuries and the prevalence of obesity in the research sample and the same dependency has been demonstrated in the issue concerning the use of the guidewire. Although the majority of predictors indicated patients with intubation difficulties, many predictors could show falsely positive results. The greater amount of intubation attempts was observed in obese patients. Further studies devoted to explain those correlations would be needed., Competing Interests: The authors have no funding and conflicts of interest to disclose.

Background: Biplanar muscle-splitting (BMS) breast augmentation is a relatively new technique for which the safe regions of dissection have not been delineated., Objectives: The authors performed cadaver dissections to elucidate the surgical anatomy of the BMS pocket and to infer the safety of this method., Methods: The breasts and chest regions of 5 female cadavers were dissected to identify anatomic landmarks and to ascertain the optimal split site in the pectoralis major. CS was defined as the lateral junction of the middle and caudal one-third of the sternum, and the sternal index was defined as the ratio of the length of the sternum to the distance from CS to the most medial major nerve branch., Results: Initiating the muscle split at CS is likely to avoid nerve injury. The mean distance from CS to the most medial nerve branch was 15.36 cm. The sternal index is a reproducible marker of the extension of the nerve branches in relation to chest size. The sternal length and the cranio-caudal length of the pectoralis major were similar, enabling reliable planning of the muscle split site., Conclusions: If dissection is limited to the safe regions delineated herein, BMS breast augmentation is likely to be a safe procedure for most patients. By maintaining the connections between the pectoralis major and its origins, a breast deformity associated with muscle contraction may be avoidable., (© 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.)

Eight new species of Charinus Simon, 1892 are described for the Brazilian Amazon, from the states of Pará (C. bichuetteae sp. n., C. bonaldoi sp. n., C. carajas sp. n., C. ferreus sp. n., C. guto sp. n. and C. orientalis sp. n.) and Amazonas (Charinus brescoviti sp. n. and C. ricardoi sp. n.). All new species can be differentiated from the other species of the genus by the number of pseudo-articles in basitibia IV, the presence/absence of median eyes, and the shape of the female gonopod. Brazil now becomes the country with the largest diversity of Amblypygi in the world, with 25 known species. Half of the new species described here have a high degree of endangerment: C. bichuetteae sp. n. is threatened by the flood caused by the hydroelectric dam of Belo Monte, and C. carajas sp. n., C. ferreus sp. n. and C. orientalis sp. n. are endangered by the iron mining in Carajás municipality and surroundings. The Charinus species here described are endemic to the Amazon Region, so in order to assure their preservation, it is strongly recommended a special care with their habitats (type localities) which are facing increasing rates of destruction and deforestation.

The sternum bone lies at the ventral midline of the thorax where it provides a critical attachment for the pectoral muscles that allow the forelimbs to raise the body from the ground. Among tetrapods, sternum morphology is correlated with the mode of locomotion: Avians that fly have a ventral extension, or keel, on their sterna, which provides an increased area for flight muscle attachment. The sternum is fused with the ribs attaching on either side; however, unlike the ribs, the sternal precursors do not originate from the somites. Despite the crucial role of the sternum in tetrapod locomotion, little attention has been given to its acquisition, evolution, and embryological development. We demonstrate an essential role for the T-box transcription factor gene Tbx5 in sternum and forelimb formation and show that both structures share an embryological origin within the lateral plate mesoderm. Consistent with this shared origin and role of Tbx5, sternum defects are a characteristic feature of Holt-Oram Syndrome (OMIM 142900) caused by mutations in TBX5. We demonstrate a link between sternum size and forelimb use across avians and provide evidence that modulation of Tbx5 expression underlies the reduction in sternum and wing size in a flightless bird, the emu. We demonstrate that Tbx5 is a common node in the genetic pathways regulating forelimb and sternum development, enabling specific adaptations of these features without affecting other skeletal elements and can also explain the linked adaptation of sternum and forelimb morphology correlated with mode of locomotion.

Sex estimation is one of the first steps in forensic anthropology to identify human remains. In absence of the skull or the pelvis, any skeletal remain becomes fundamental for identification, especially in mass-disaster cases. The sternum is a potentially useful element in anthropological analysis with a high recovery rate in both forensic-and archaeological context. This study aims to develop classification functions for use in Spanish population. For this, sternum sexual dimorphism is studied in a sample of 105 individuals, known age-at-death, ancestry and sex, from San José Municipal Cemetery of Granada (Spain). Lin's concordance correlation coefficient was used to estimate intra-and inter-observer error. In discriminant analysis for estimating sex, cross-validation shows accuracy rates exceeds 90% for sternum body length and maximum width (91.8%), or total length with maximum width (90.7%). Isolated variables with higher accuracy rates are total sternum length (89.1%), and sternum body length (87%). Although there is compliance with Hyrtl's law it is not useful for estimating sex in Spanish population. These discriminant functions have also been validated successfully in two samples from Portugal (Coimbra identified skeletal collection--CISC, and 21st century identified ckeletal collection--Santarém XXI): the variables with higher accuracy rates sternum total length with its maximum width (92.3% the correctly classified individual in the sample CISC; and 83.5% in the sample of Santarém XXI) and the sternum total length (92.1% and 78.5%, respectively). The discriminant functions achieved with the collection of the San Jose cemetery of Granada can be applied to current remains, provided that study populations present a similar sexual dimorphism, like the two samples from Portuguese population presented in this study., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Background: The pectoralis major typically is manipulated for implant coverage and pocket design in subpectoral breast augmentation. An understanding of its anatomy can guide successful creation of the implant pocket., Objectives: The authors evaluated the anatomy of the sternal origin of the pectoralis major to inform surgical planning, help establish a technique for subpectoral augmentation mammaplasty, and identify the most common locations of perforators., Methods: The sternal origins of 24 pectoralis major muscles were dissected and examined in 15 female cadavers to determine the structure and width of the pectoralis major sternal origin and its relationship to the locations of internal mammary perforators., Results: The average width of the sternal origin of the pectoralis major was 7.1 mm (range, 3 mm-1.8 cm). This width decreased slightly from the second rib to the second intercostal space and then increased progressively in the caudal direction toward the fifth rib. The sternal origin terminated an average of 5.4 mm (range, 1-16 mm) from the midline, with the greatest distance at the fifth rib and large variability throughout. A row of perforators from the internal mammary artery traversed the subpectoral space an average of 2.7 cm from the midline (range, 1-3.7 cm)., Conclusions: The sternal origin of the pectoralis major was thin and highly variable, suggesting that its partial release for implant medialization during subpectoral augmentation is unsafe., (© 2014 The American Society for Aesthetic Plastic Surgery, Inc.)

Anchiornis (Deinonychosauria: Troodontidae), the earliest known feathered dinosaur, and Sapeornis (Aves: Pygostylia), one of the basalmost Cretaceous birds, are both known from hundreds of specimens, although remarkably not one specimen preserves any sternal ossifications. We use histological analysis to confirm the absence of this element in adult specimens. Furthermore, the excellent preservation of soft-tissue structures in some specimens suggests that no chondrified sternum was present. Archaeopteryx, the oldest and most basal known bird, is known from only 10 specimens and the presence of a sternum is controversial; a chondrified sternum is widely considered to have been present. However, data from Anchiornis and Sapeornis suggest that a sternum may also have been completely absent in this important taxon, suggesting that the absence of a sternum could represent the plesiomorphic avian condition. Our discovery reveals an unexpected level of complexity in the early evolution of the avian sternum; the large amount of observable homoplasy is probably a direct result of the high degree of inherent developmental plasticity of the sternum compared with observations in other skeletal elements.

Introduction: The sternocleidomastoid (SCM) muscle is a major muscle of the neck. Classically, this muscle is attached below the sternum and clavicle, although the mode of attachment might vary. As the SCM is related to numerous important neurovascular structures, its variable anatomy is clinically relevant, particularly for neck surgeries. A cadaveric study was performed to establish the variations present in the mode of attachment of the SCM muscle in an Indian population., Methods: We studied the variations in the attachment of the SCM muscle during the dissection of 18 cadavers for undergraduate teaching in two medical colleges in West Bengal, India., Results: Variations in the attachment of the SCM muscle were found in 5 (27.8%) specimens. Of these five specimens, three had unilateral variations and two had bilateral variations. In each specimen, the modes of presentation of the SCM and its fusion with the major bulk were also different., Conclusion: In this study, we found variations in the attachment of the SCM muscle in more than a quarter of the specimens dissected. Surgeons should bear in mind such variations when performing neck surgeries.

Examined bones were obtained from eight adult African giant rats, Cricetomys gambianus Waterhouse. Animals used had an average body mass of 730.00 ± 41.91 gm and body length of 67.20 ± 0.05 cm. The vertebral formula was found to be C7, T13, L6, S4, Ca31-36. The lowest and highest points of the cervicothoracic curvature were at C5 and T2, respectively. The spinous process of the axis was the largest in the cervical group while others were sharp and pointed. The greatest diameter of the vertebral canal was at the atlas (0.8 cm) and the lowest at the caudal sacral bones (2 mm). The diameter of the vertebral foramen was the largest at C1 and the smallest at the S4; the foramina were negligibly indistinct caudal to the sacral vertebrae. There were 13 pairs of ribs. The first seven pairs were sternal, and six pairs were asternal of which the last 2-3 pairs were floating ribs. The sternum was composed of deltoid-shaped manubrium sterni, four sternebrae, and a slender processus xiphoideus. No sex-related differences were observed. The vertebral column is adapted for strong muscular attachment and actions helping the rodent suited for speed, agility, dexterity, and strength which might enable it to overpower prey and escape predation.

Nonmetric traits are quasi-continuous skeletal traits that cannot be measured, but are observed as ranks or scores. In the present study, 8 nonmetric traits of sternum were examined from 343 sternums collected from the autopsy cases. More males, particularly older subjects, had a mesosternal foramen. The frequency of mesosternal foramen, arch-shaped prominence on the manubrium and radial strips on mesosternum significantly increased but that of lateral projection of manubrium decreased in the 30+ year age-group (older individuals). The denticulate costal incisures were found mostly in females and younger subjects; however, the crescent incisures and arch shaped prominence of manubrium were noticed mainly in males and older subjects. Majority of subjects had 'deep and narrow' jugular notch and xiphi-sternum was 'bifid' or 'oblong' in males and 'small sized' in females and younger subjects. Xiphi-sternum was generally found absent in females and younger subjects. The different shapes of costal incisures, jugular notch and xiphoid process were found to have significant sex and age differences. The number of cases with fused elements significantly increased with advancing age in both sexes. The sternal elements' fusion showed a variable pattern and hence was not found to be a reliable criterion. Chi-square analysis revealed significant differences between two age-groups of individual sex in the distribution of 3 of the 8 nonmetric traits. Significant sex and age differences were noticed in the frequency of occurrence of mesosternal foramina between the younger and older age groups in both the sexes. The logistic regression analysis of the scores classified 73.8% sternums to their sex category and 70.0% sternums to their age-group. Though present findings may not be enough for absolute personal identification, these traits can still serve as important identification tools if antemortem radiographs/CT or MRI scans are available for comparisons, or help classify an unknown sternum to its sex or age category based on the morphological features discussed in present study., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Forensic anthropologists have proposed different sex determination methods based on metric and non-metric skeletal features of various bones. The main objective of the present investigation was to evaluate sexual dimorphism in human sternum and make comparative analysis based on studies by several workers who used different methodologies and techniques. For this study, 343 sternums were collected and examined from 252 male and 91 female cadavers of a north Indian population. Significant differences were noticed between the mean sternal measurements measured directly on bone specimens in present study and those measured indirectly on radiographs or CT scan images reported by previous researchers. Comparative analysis of absolute sternal measurements showed concordance with some earlier Indian studies but discordance with most other population studies conducted worldwide. Limiting points gave much higher sex accuracy levels than the demarking points. The calculated multivariate DFA equation (y=-14.222+0.076MBL+0.137WS&#95;1) and regression equation (y=36.675-0.198MBL-0.405WS&#95;1) correctly estimated sex of 84.8% and 89.8% sternums, respectively. Multivariate analyses gave more striking results than the univariate ones. Though logistic regression analysis gave higher accuracy rates but discriminant function analysis was found to be a more reliable statistical tool for sex determination because of low sex biases. The sexing efficacies of the dry and wet sternums did not differ significantly, so bone specimens are equally reliable as the radiographs or CT scans for sex determination. The sternal area and the combined length were found the best parameters among all the criteria and methods considered. The changes in the body proportions, nutritional, environmental, climatic changes, etc., are attributable to secular changes in sterna measurements when compared to Jit et al. [13]. The osteometric techniques are better representative of biological identity of the deceased because of some inherent defects associated with radiographic methods. Like other sex-predictive bones of the human skeleton, the sternum can also be a valuable adjunct for sex determination of unknown subjects., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

The sternalis muscle is an accessory muscle located in the anterior thoracic region, which is relatively unfamiliar to clinicians and surgeons. To date, no data from the Iranian population have been published. Here, a rare case of a sternalis muscle is presented. In addition, this anomalous muscle was observed along with other visceral and vascular anomalies. This case is unique and provides significant information to radiologists, angiologists and surgeons seeking to apply safer interventions. It is also imperative for better interpretation of mammographic images and in reconstructive surgery.

Ossified gastralia, clavicles and sternal ribs are known in a variety of reptilians, including dinosaurs. In sauropods, however, the identity of these bones is controversial. The peculiar shapes of these bones complicate their identification, which led to various differing interpretations in the past. Here we describe different elements from the chest region of diplodocids, found near Shell, Wyoming, USA. Five morphotypes are easily distinguishable: (A) elongated, relatively stout, curved elements with a spatulate and a bifurcate end resemble much the previously reported sauropod clavicles, but might actually represent interclavicles; (B) short, L-shaped elements, mostly preserved as a symmetrical pair, probably are the real clavicles, as indicated by new findings in diplodocids; (C) slender, rod-like bones with rugose ends are highly similar to elements identified as sauropod sternal ribs; (D) curved bones with wide, probably medial ends constitute the fourth morphotype, herein interpreted as gastralia; and (E) irregularly shaped elements, often with extended rugosities, are included into the fifth morphotype, tentatively identified as sternal ribs and/or intercostal elements. To our knowledge, the bones previously interpreted as sauropod clavicles were always found as single bones, which sheds doubt on the validity of their identification. Various lines of evidence presented herein suggest they might actually be interclavicles - which are single elements. This would be the first definitive evidence of interclavicles in dinosauromorphs. Previously supposed interclavicles in the early sauropodomorph Massospondylus or the theropods Oviraptor and Velociraptor were later reinterpreted as clavicles or furculae. Independent from their identification, the existence of the reported bones has both phylogenetic and functional significance. Their presence in non-neosauropod Eusauropoda and Flagellicaudata and probable absence in rebbachisaurs and Titanosauriformes shows a clear character polarity. This implicates that the ossification of these bones can be considered plesiomorphic for Sauropoda. The proposed presence of interclavicles in sauropods may give further support to a recent study, which finds a homology of the avian furcula with the interclavicle to be equally parsimonious to the traditional theory that furcula were formed by the fusion of the clavicles. Functional implications are the stabilizing of the chest region, which coincides with the development of elongated cervical and caudal vertebral columns or the use of the tail as defensive weapon. The loss of ossified chest bones coincides with more widely spaced limbs, and the evolution of a wide-gauge locomotor style., (© 2012 The Authors Journal of Anatomy © 2012 Anatomical Society.)

Stature estimation is one of the four attributes of the biological profile obtained from human skeletal remains. The length of the long bones has been consistently used to estimate stature from regression equations, but these may be useless when dealing with fresh or decomposed mutilated remains. Until recently, there was no consistent assessment of the reliability of measurements of the sternum for stature estimation. The purpose of this paper is to test previously developed regression formulae for stature based on measurements of the dry sternum and to assess the reliability of measurements of the fresh sternum in estimating stature. The formulae developed by Menezes et al. and Singh et al. were applied to a sample of 5 known stature skeletons from the identified human skeletal collection curated at the National Museum of Natural History, in Lisbon, Portugal. Testing of these formulae showed that estimated stature confidence intervals do not allow discrimination between individuals with similar stature. The length of the fresh sternum was measured on a sample of 45 male individuals autopsied at the National Institute of Legal Medicine - North Delegation (Porto, Portugal). Cadaver length was regressed on sternum length and a simple linear regression formula was obtained. The regression model provided a 95% confidence interval of 13.32 cm and a correlation coefficient of only 0.329. Compared to other studies, regression formulae based on the length of the sternum provided considerably larger standard errors than that based on long bone lengths. These results suggest that the length of the sternum has limited forensic value and relatively low reliability in estimating stature from mutilated human skeletal remains, either skeletonized or fresh., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Estimating the sex of skeletal remains is critical in creating the biological profile of an adult individual. Previous research has shown that analyzing the sternum may lead to an accurate estimation of sex based on studies performed on various populations around the globe, such as Indian, European, African, Canadian and North American. The motivation of the current study is to develop classification functions and sectioning points for use in forensic investigations in the United States. The majority of previously published methods are population specific, meaning the data would not prove useful in the United States. For this study, sternal measurements were collected from the William M. Bass Donated Skeletal Collection located at The University of Tennessee, Knoxville following the metric definitions provided by Schwartz and Bass. This collection consists of recent skeletal remains with known age at death, ancestry and sex. Material for the present study consisted of 410 human sterna: 285 male (256 American White/29 American Black) and 125 female (120 American White/5 American Black). Previous studies analyze the applicability of Hyrtl's law in the estimation of sex. This law follows that the mesosternum is greater than twice the length of the manubrium in males and in females the length of the manubrium is greater than half the length of the mesosternum. In this study, comparisons of the proportion of the length of the manubrium to the length of the mesosternum were performed to determine if Hrytl's law is applicable in an American population. Comparisons of these measurements between individuals identified as American Black and American White were analyzed to determine whether this method could be used on both population groups. Further, discriminant function analysis was used to estimate sex and provide a population specific classification function for use in the United States. The discriminate function analysis produced an overall cross-validation classification rate of 84.12% for sex estimation. The cross-validation classification rate for males and females was 80.00% and 88.24%, respectively., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: A greater structural expansion of the rib cage in females compared with males has been described in cystic fibrosis (CF) patients; however, conflicting data exist as to whether an elongation of the bony ribs and sternum contributes to this expansion., Objectives: To compare height-adjusted anthropometric measures and sternum length between a group of normal subjects and a group of CF patients of both sexes., Methods: Anthropometric measurements including body weight, height, upper and lower limb lengths, biacromial distance and pelvic width were measured in the standing position in 30 CF patients (13 males) and 28 normal subjects (14 males). Body surface measurements of anterior-posterior and lateral diameters of the rib cage at functional residual capacity, and sternum length were also obtained., Results: Compared with normal subjects, CF patients had lower body weight, shorter standing height and shorter height-adjusted upper and lower limb lengths. Rib cage diameters were greater in CF patients than in normal subjects of either sex, but height-adjusted sternum length was not different., Conclusion: Significant differences in bodily proportions were found between normal subjects and CF patients, suggesting a differential growth pattern for the trunk and limbs. However, increased rib cage dimensions with lung hyperinflation and airway obstruction was not associated with an elongation of the sternum.

In Australia, particularly Western Australia, there is a relative paucity of contemporary population-specific morphometric standards for the estimation of sex from unknown skeletal remains. This is largely a historical artefact from lacking, or poorly documented, repositories of human skeletons available for study. However, medical scans, e.g. MSCT (multislice spiral computed tomography) are an ingenious and practical alternative source for contemporary data. To that end, this study is a comprehensive analysis of sternal sexual dimorphism in a sample of modern Western Australian (WA) individuals with a main purpose to develop a series of statistically robust standards for the estimation of sex. The sample comprises thoracic MSCT scans, with a mean of 0.9 millimeter (mm) slice thickness, on 187 non-pathological sterna. Following 3D volume rendering, 10 anatomical landmarks were acquired using OsiriX(®) (version 3.9) and a total of 8 inter landmark linear measurements were calculated using Morph Db (an in-house developed database application). Measurements were analyzed using basic descriptive statistics and discriminant function analyses, with statistical analyses performed using SPSS 19.0. All measurements are sexually dimorphic and sex differences explain 9.8-47.4% of sample variance. The combined length of the manubrium and body, sternal body length, manubrium width, and corpus sterni width at first sternebra contribute significantly to sex discrimination and yield the smallest sex-biases. Cross-validated classification accuracies, i.e., univariate, stepwise and direct function, are 72.2-84.5%, with a sex bias of less than 5%. We conclude that the sternum is a reliable element for sex estimation among Western Australians., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Fossil hominin mesosterna, while scarce, can provide useful morphological data in addition to rib remains regarding aspects of thoracic size and shape. These data, in turn, can address hypotheses related to respiratory dynamics, climatic adaptation, and ecogeographical patterning. In this study, we re-evaluate the anatomical representation of the mesosternum of the Regourdou 1 Neandertal individual that alters key aspects of the original description of the fossil remains. We compare this specimen together with the mesosterna of the Kebara 2 Neandertal male individual and the Tabun C1 Neandertal female individual to a large extant modern sample. Our study shows that the current evidence available for Neandertals indicates longer mesosterna, reflecting larger thorax sizes among Neandertals, in comparison with extant humans. Additionally, while this study weakens previous suggestions of ecogeographically mediated differences in the size and shape of upper thorax between Neandertals from the Mediterranean Levant and those deriving from Western Europe, we cannot unambiguously disprove the notion of such clinal differences., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The sternum is one of the most important and characteristic skeletal elements in living birds, highly adapted for flight and showing a diverse range of morphologies. New exceptional material of young juvenile specimens from the Early Cretaceous Jehol Group in northeastern China reveals the unique sequence of development in the sternum of Enantiornithes, the dominant clade of Cretaceous birds. We recognize six ossifications that together form the sternum, three of which were previously unknown. Here we show that although basal living birds apparently have retained the dinosaurian condition in which the sternum develops from a bilateral pair of ossifications (present in paravian dinosaurs and basal birds), the enantiornithine sternal body primarily develops from two unilateral proximo-distally arranged ossifications. This indicates that although superficially similar, the sternum formed very differently in enantiornithines and ornithuromorphs, suggesting that several ornithothoracine sternal features may represent parallelism. This highlights the importance of ontogenetic studies for understanding homology and the evolution of skeletal features in palaeontology.

Radiology is an important diagnostic instrument in avian medicine, but standard measurement ranges for the objective evaluation of radiographs of birds are rare. To establish radiographic reference ranges for the critically endangered Spix's macaw (Cyanopsitta spixii), we measured radiographic silhouettes of the heart, liver, kidneys, spleen, proventriculus, and keel of the sternum on 29 radiographs taken under standardized conditions in adult and juvenile, clinically healthy birds. Ratios were determined for the proventricular diameter-to-keel height, the width of the heart to the width of the thorax, and for the "hourglass shape" (ratio of the width of the heart to the width of the liver). No significant differences were found between the sexes among the adult birds. Compared with adult birds, juvenile females had a significantly larger heart width (19.8 +/- 1.4 mm versus 21.2 +/- 0.7 mm), ratio of the heart width to the thorax width (0.86 +/- 0.08 versus 0.94 +/- 0.09), and horizontal width of the spleen (7.7 +/- 0.6 mm versus 8.5 +/- 0.4 mm). Results of radiographic measurements in the Spix's macaws were comparable to those published from other psittacine species. These reference ranges will facilitate a more objective radiographic evaluation of captive Spix's macaws.

Aim: This study was conducted to determine normal ranges of sterno-mental distance (SMD) and thyromental distance (TMD) and to examine the relationship of these measurements to each other and the body mass index (BMI)., Methods: The SMD, TMD and BMI were assessed in a total of 409 apparently healthy adult subjects comprising 218 male and 190 female participants who volunteered for the study. The parameters were measured by standard methods and the obtained data analysed for the degree of association using Pearson Correlation Statistics., Results: Mean values of SMD and TMD were significantly higher in males than in females. The BMI was statistically same in both sexes. Sterno-mental distance correlated positively with TMD in both sexes (r = 0.86, p = 0.005) while BMI correlated negatively with SMD (r = -0.166, p = 0.108) as well as to the TMD (r = -0.147, p = 0.04) in both sexes., Conclusion: In young healthy adult populations the SMD and TMD are strongly related to each other but are unrelated to the BMI. Males tend to have on average longer SMD and TMD as compared to females. Our findings could be a useful tool during pre-anaesthetic airway assessment of patients.

Skeletal height estimation from regression analysis of eight sternal lengths in the subjects of Chandigarh zone of Northwest India is the topic of discussion in this study. Analysis of eight sternal lengths (length of manubrium, length of mesosternum, combined length of manubrium and mesosternum, total sternal length and first four intercostals lengths of mesosternum) measured from 252 male and 91 female sternums obtained at postmortems revealed that mean cadaver stature and sternal lengths were more in North Indians and males than the South Indians and females. Except intercostal lengths, all the sternal lengths were positively correlated with stature of the deceased in both sexes (P < 0.001). The multiple regression analysis of sternal lengths was found more useful than the linear regression for stature estimation. Using multivariate regression analysis, the combined length of manubrium and mesosternum in both sexes and the length of manubrium along with 2nd and 3rd intercostal lengths of mesosternum in males were selected as best estimators of stature. Nonetheless, the stature of males can be predicted with SEE of 6.66 (R(2) = 0.16, r = 0.318) from combination of MBL+BL&#95;3+LM+BL&#95;2, and in females from MBL only, it can be estimated with SEE of 6.65 (R(2) = 0.10, r = 0.318), whereas from the multiple regression analysis of pooled data, stature can be known with SEE of 6.97 (R(2) = 0.387, r = 575) from the combination of MBL+LM+BL&#95;2+TSL+BL&#95;3. The R(2) and F-ratio were found to be statistically significant for almost all the variables in both the sexes, except 4th intercostal length in males and 2nd to 4th intercostal lengths in females. The 'major' sternal lengths were more useful than the 'minor' ones for stature estimation The universal regression analysis used by Kanchan et al. [39] when applied to sternal lengths, gave satisfactory estimates of stature for males only but female stature was comparatively better estimated from simple linear regressions. But they are not proposed for the subjects of known sex, as they underestimate the male and overestimate female stature. However, intercostal lengths were found to be the poor estimators of stature (P < 0.05). And also sternal lengths exhibit weaker correlation coefficients and higher standard errors of estimate., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Sternalis is an anomalous muscle found occasionally in the anterior part of the thorax. During routine dissection sternalis muscle was found in a male cadaver. This rare anatomic variant is reported in 8% of the population. In the present case, the muscle was found bilaterally, placed obliquely on either side of the sternum. It originated by tendinous fibres from the lower costal cartilages and inserted to the manubriosternal junction. The right side muscle was well developed whereas the left one was reduced in size. The pectoralis major and minor were normal. The knowledge of sternalis is important for radiologists and surgeons.

Purpose: To evaluate the mammographic findings of the sternalis muscle and discuss appropriate diagnostic approaches., Materials and Methods: Ten years of records from our mammography unit were retrospectively examined for the presence of the sternalis muscle. This variant was seen in 10 women out of the 52,930 examined, and the mammograms of these patients were reevaluated. The size, shape and contours of the muscle were reviewed on the craniocaudal (CC) and mediolateral oblique (MLO) views. Yearly mammograms were assessed to evaluate follow-up changes. Extra examinations were reviewed, including ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI)., Results: The prevalence of the sternalis muscle was 0.018%. Its contours were well-defined, irregular or spiculated, and the diameter ranged from 3-4 mm to 15 mm. The shape of the muscle varied from slightly bulging to round or triangular. The muscle was detected on MLO projections in three patients as an inferior soft tissue density at the posterior edge of the breast, continuous with the pectoralis muscle. Distinct pulling of the breast led to variations in the appearance of the muscle on yearly mammograms. US examinations were normal in all patients. CT and MRI showed the muscle clearly., Conclusion: The appearance of the sternalis muscle may vary on CC views. It may also be detected on MLO projections. The ability to visualize the muscle depends on proper positioning. Knowledge of its detectability on mammograms will prevent the misdiagnosis of a mass and prevent further unnecessary investigations.

The correct assessment of sex from the human skeleton is of fundamental importance in forensic medicine and bioarchaeology. In South Africa, unidentified remains are often fragmentary, making it necessary to estimate sex from a variety of skeletal elements. The purpose of the present study was to evaluate the sex discriminating potential of the sternum in black South Africans using standard osteometric techniques. A sample of 123 males and 83 females drawn from the Raymond A. Dart Collection of Human Skeletons and the Pretoria Bone Collection was used. The results demonstrated that all eight sternal variables, including both dimensions and indices, were highly sexually dimorphic in this population. A stepwise discriminant function procedure, which selected corpus sterni length and manubrium width, correctly identified 86.4% of the individuals in the study sample. Additional multivariate discriminant equations incorporating dimensions for either the manubrium or corpus sterni yielded sex prediction rates of 80.6% and 84.5%, respectively. Sternal area, when used in isolation, produced the highest sex classification accuracy with 86.9% of specimens correctly assigned. The remaining single variable functions, which can be applied when well-preserved or complete sterna are not available for analysis, provided classification accuracies ranging from 68.4% to 83.5%. These classification results are comparable to those reported in previous investigations concerning sex estimation of black South Africans for other postcranial elements., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Introduction: One of the most important data that can be obtained from bones is sex determination for which the recommended method is taking metric measurements. Metric measurements can be performed directly on dried bones obtained from the cadaver or indirectly from their radiographs., Aim: We assessed the accuracy of sex determination and the applicability of previously defined rules using the sternum and 4th rib measurement data from chest multislice computed tomography (MSCT) imaging of 340 patients and developed a model/formula that would provide the best way to determine sex., Methods: We analyzed the chest MSCT of 340 patients (143 females, 197 males; mean age: 57.6+/-15.2 years) and created a coronal image parallel to the sternal long axis and a coronal image at the level of sternal ending of the 4th rib. The 5 sternal measurements [length of the manubrium and sternal body, combined length of the manubrium and sternal body (CL), manubrium width and corpus sterni width] and 4th rib width (FRW) described in the literature were obtained. Sternal index (SI) and sternal area (SA) were calculated from these measurements., Results: The left FRW values were used for sex determination as the left FRW was found to be more significant than the right FRW. An accuracy of over 80% was achieved for sex determination when the "142 rule" was used for CL only, a cut-off value of 5600 mm(2) for SA only and a cut-off value of 16 mm for FRW only. We found that Hyrtl's law and SI did not provide adequate accuracy for sex determination in our patients. The model with the highest accuracy (88.2%) for sex determination used SA and FRW together. We also believe that the best predictors for sex determination using the sternum and 4th rib are SA and FRW, similar to the Torwalt and Hoppa report., Conclusion: Radiological methods such as MSCT are useful in making reliable measurements to be used in various anthropological and forensic investigations and determining their accuracy., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)

Chondrocyte differentiation is strictly regulated by various transcription factors, including Runx2 and Runx3; however, the physiological role of Runx1 in chondrocyte differentiation remains unknown. To examine the role of Runx1, we generated mesenchymal-cell-specific and chondrocyte-specific Runx1-deficient mice [Prx1 Runx1(f/f) mice and alpha1(II) Runx1(f/f) mice, respectively] to circumvent the embryonic lethality of Runx1-deficient mice. We then mated these mice with Runx2 mutant mice to obtain mesenchymal-cell-specific or chondrocyte-specific Runx1; Runx2 double-mutant mice [Prx1 DKO mice and alpha1(II) DKO mice, respectively]. Prx1 Runx1(f/f) mice displayed a delay in sternal development and Prx1 DKO mice completely lacked a sternum. By contrast, alpha1(II) Runx1(f/f) mice and alpha1(II) DKO mice did not show any abnormal sternal morphogenesis or chondrocyte differentiation. Notably, Runx1, Runx2 and the Prx1-Cre transgene were co-expressed specifically in the sternum, which explains the observation that the abnormalities were limited to the sternum. Histologically, mesenchymal cells condensed normally in the prospective sternum of Prx1 DKO mice; however, commitment to the chondrocyte lineage, which follows mesenchymal condensation, was significantly impaired. In situ hybridization analyses demonstrated that the expression of alpha1(II) collagen (Col2a1 - Mouse Genome Informatics), Sox5 and Sox6 in the prospective sternum of Prx1 DKO mice was severely attenuated, whereas Sox9 expression was unchanged. Molecular analyses revealed that Runx1 and Runx2 induce the expression of Sox5 and Sox6, which leads to the induction of alpha1(II) collagen expression via the direct regulation of promoter activity. Collectively, these results show that Runx1 and Runx2 cooperatively regulate sternal morphogenesis and the commitment of mesenchymal cells to become chondrocytes through the induction of Sox5 and Sox6.

Background: The holotype of the theropod non-avian dinosaur Microraptor gui from the Early Cretaceous of China shows extensive preservation of feathers in a halo around the body and with flight feathers associated with both the fore and hindlimbs. It has been questioned as to whether or not the feathers did extend into the halo to reach the body, or had disassociated and moved before preservation. This taxon has important implications for the origin of flight in birds and the possibility of a four-winged gliding phase., Methodology/principal Findings: Examination of the specimen under ultraviolet light reveals that these feathers actually reach the body of the animal and were not disassociated from the bones. Instead they may have been chemically altered by the body tissues of the animal meaning that they did not carbonise close into the animal or more likely were covered by other decaying tissue, though evidence of their presence remains., Conclusions/significance: These UV images show that the feathers preserved on the slab are genuinely associated with the skeleton and that their arrangement and orientation is likely correct. The methods used here to reveal hidden features of the specimen may be applicable to other specimens from the fossil beds of Liaoning that produced Microraptor.

The excavated type of rhomboid fossa of the clavicle is a relatively neglected anatomical structure that can potentially cause diagnostic problems. Its unilateral occurrence may be confused by the physician as avascular necrosis, osteomyelitis, or even a tumour. We studied 80 routine chest radiographs and identified the clavicles with excavated type of rhomboid fossa. The sex, sidedness, and handedness were recorded. An excavated type of rhomboid fossa was present in 43 clavicles (26.88%), appearing more frequently in males than in females. In addition, the incidence of the excavated type of rhomboid fossa was greater on the right side than on the left. That type of fossa was also present more frequently on the right side in right-handed specimens and on the left side in left-handed specimens. The high incidence of the excavated type of rhomboid fossa on the dominant hand supports the mechanical theory of fossa formation. Radiologists and physicians should be aware of this fossa, as it may resemble a pathological condition.

The aims of the study were to identify factors that may result in difficulties in intubation, and to compare the results obtained when an experienced and when a less experienced anaesthesiologist was involved. The 96 patients included in the study were evaluated for difficult intubation according to the following scales: Mallampati, upper lip bite test (ULBT) and Patil. The mobility of the cervical segments of the vertebral column, the distance between the jugular notch of the sternum and the chin and the anatomical constitution of the body were other factors that were taken into consideration. Statistical analysis was performed in order to identify factors that may result in difficulties in intubation for an experienced and for a less experienced anaesthesiologist.

The functional significance of the uncinate processes to the ventilatory mechanics of birds was examined by combining analytical modeling with morphological techniques. A geometric model was derived to determine the function of the uncinate processes and relate their action to morphological differences associated with locomotor specializations. The model demonstrates that uncinates act as levers, which improve the mechanical advantage for the forward rotation of the dorsal ribs and therefore lowering of the sternum during respiration. The length of these processes is functionally important; longer uncinate processes increasing the mechanical advantage of the Mm. appendicocostales muscle during inspiration. Morphological studies of four bird species showed that the uncinate process increased the mechanical advantage by factors of 2-4. Using canonical variate analysis and analysis of variance we then examined the variation in skeletal parameters in birds with different primary modes of locomotion (non-specialists, walking and diving). Birds clustered together in distinct groups, indicating that uncinate length is more similar in birds that have the same functional constraint, i.e. specialization to a locomotor mode. Uncinate processes are short in walking birds, long in diving species and of intermediate length in non-specialist birds. These results demonstrate that differences in the breathing mechanics of birds may be linked to the morphological adaptations of the ribs and rib cage associated with different modes of locomotion.

Purpose: To identify the lymph nodes positioned along the internal mammary vessels in isolated sternum of human cadaver and to standardize the surgical approach to those nodes, in order to establish anatomical landmarks to be used with the current techniques of mammary gland sentinel lymph node detection., Methods: Ten sternum plates removed from unclaimed cadavers were used in this study. Sternal plates were removed using bilateral incisions of the ribs at the midclavicular lines. The characterization of the internal mammary vessels and the anatomical integrity of the parietal pleura were indispensable requirements during the procedure., Results: A total of 29 lymph nodes were removed from the 2nd (13) and the 3rd (16) intercostals spaces. Almost 50% of all nodes collected were located medially to the vessels., Conclusion: The approach used is a reliable surgical technique for removing lymph node from sternal plates. The model is therefore valuable for breast surgeons training in sentinel node biopsy, an important procedure for breast cancer patients.

The inspiratory intercostal muscles enhance the force generated by the diaphragm during lung expansion. However, whether the diaphragm also alters the force developed by the inspiratory intercostals is unknown. Two experiments were performed in dogs to answer the question. In the first experiment, external, cranially oriented forces were applied to the different rib pairs to assess the effect of diaphragmatic contraction on the coupling between the ribs and the lung. The fall in airway opening pressure (deltaPa(O)) produced by a given force on the ribs was invariably greater during phrenic nerve stimulation than with the diaphragm relaxed. The cranial rib displacement (Xr), however, was 40-50% smaller, thus indicating that the increase in deltaPa(O) was exclusively the result of the increase in diaphragmatic elastance. In the second experiment, the parasternal intercostal muscle in the fourth interspace was selectively activated, and the effects of diaphragmatic contraction on the deltaPa(O) and Xr caused by parasternal activation were compared with those observed during the application of external loads on the ribs. Stimulating the phrenic nerves increased the deltaPa(O) and reduced the Xr produced by the parasternal intercostal, and the magnitudes of the changes were identical to those observed during external rib loading. It is concluded, therefore, that the diaphragm has no significant synergistic or antagonistic effect on the force developed by the parasternal intercostals during breathing. This lack of effect is probably related to the constraint imposed on intercostal muscle length by the ribs and sternum.