The anatomical growth of the thoracic cage in adolescents with specific reference to axial growth comparing the right and left hemithorax

This study has demonstrated the changing volume of both the anterior and posterior thorax in normal adolescents (without spinal or thoracic deformity), differentiating for both sex and age, to further understand how the thorax grows, along with the differences in growth between the anterior and posterior thorax. The thorax was measured on axial CT slices at every vertebral level from T3 to T12 in a series of scans previous taken for routine clinical care. Measurements taken were the anteroposterior thoracic distance and the area of the anterior and posterior rib prominences on either side of the thorax. Data was analyzed per vertebral level, differentiating for age and sex. There were 486 CT scans analyzed (257 males and 229 females) between the ages of 8 and 18 years. The analysis identified that for the anterior thorax, there are three phases of growth with an initial slow increase in volume, followed by a stabilization of little growth, followed by another phase of a more rapid increase in volume. For the posterior thorax, there was a gradual increase in area with increasing age. This study demonstrates that the shape of the thorax is age and sex dependent, with males having both a greater width and depth of thorax compared to females. Of particular note is the difference in patterns of growth between the anterior and posterior thorax. This information will add to the understanding of normal growth, which will aid in the management of conditions where that growth is disturbed.     

A Comparative Assessment of the Size of the Frontal Air Sinus in the Giraffe (Giraffa camelopardalis)

The current study examines the frontal air sinus of the giraffe (Giraffa camelopardalis) cranium with the aim of evaluating previously offered hypotheses as to why they have such an atypically voluminous frontal sinus relative to other artiodactyls. To date, no quantification of the frontal sinus in the adult or developing giraffe has been undertaken or compared to other artiodactyl species. Crania from eight species of adult artiodactyls, and giraffes varying in age from newborn to adult, were studied using CT scans to provide a volumetric assessment of the frontal sinus. Sinus volume was strongly correlated to cranial mass in the male giraffe ontogenetic series. The adult giraffe of both sexes were found to possess a far larger than predicted sinus volume relative to the relationship between frontal sinus volume and cranial mass observed in the other adult artiodactyls. Our results suggest that the volume of the frontal sinus in the giraffe is likely to be unique among artiodactyls, and the potential function and evolution we consider in light of several previously articulated hypotheses. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.     

Cervical vertebral body growth and emergence of sexual dimorphism: a developmental study using computed tomography

The size and shape of human cervical vertebral bodies serve as a reference for measurement or treatment planning in multiple disciplines. It is therefore necessary to understand thoroughly the developmental changes in the cervical vertebrae in relation to the changing biomechanical demands on the neck during the first two decades of life. To delineate sex‐specific changes in human cervical vertebral bodies, 23 landmarks were placed in the midsagittal plane to define the boundaries of C2 to C7 in 123 (73 M; 50 F) computed tomography scans from individuals, ages 6 months to 19 years. Size was calculated as the geometric area, from which sex‐specific growth trend, rate, and type for each vertebral body were determined, as well as length measures of local deformation‐based morphometry vectors from the centroid to each landmark. Additionally, for each of the four pubertal‐staged age cohorts, sex‐specific vertebral body wireframes were superimposed using generalized Procrustes analysis to determine sex‐specific changes in form (size and shape) and shape alone. Our findings reveal that C2 was unique in achieving more of its adult size by 5 years, particularly in females. In contrast, C3–C7 had a second period of accelerated growth during puberty. The vertebrae of males and females were significantly different in size, particularly after puberty, when males had larger cervical vertebral bodies. Male growth outpaced female growth around age 10 years and persisted until around age 19–20 years, whereas females completed growth earlier, around age 17–18 years. The greatest shape differences between males and females occurred during puberty. Both sexes had similar growth in the superoinferior height, but males also displayed more growth in anteroposterior depth. Such prominent sex differences in size, shape, and form are likely the result of differences in growth rate and growth duration. Female vertebrae are thus not simply smaller versions of the male vertebrae. Additional research is needed to further quantify growth and help improve age‐ and sex‐specific guidance in clinical practice.     

Influence of age and sex on lumbar vertebral morphometry determined using sagittal magnetic resonance imaging.

We evaluated age-related changes in the morphometric features of lumbar vertebrae in both sexes using magnetic resonance imaging (MRI). Midsagittal MRI scans of 366 individuals (156 males, 210 females; 25-82 years old) were evaluated retrospectively. The anterior height (H(a)), central height (H(c)), posterior height (H(p)), and anteroposterior diameter (D) of the body of each lumbar vertebra were measured. These measurements were used to calculate three indices, namely, the anterior wedge index (H(a)/H(p)), the biconcavity index (H(c)/H(p)), and the compression index (H(p)/D). The values of each of the three indices for the upper lumbar vertebrae of females were higher than those of the same vertebrae in males. The values of the compression index for all lumbar vertebrae decreased with age in females, whereas in males the compression index of the L1-L4 vertebrae decreased with age. No significant changes were observed in the value of the anterior wedge index in either sex. The biconcavity indices of the L1 and L5 vertebrae decreased with age in males. These results may be useful for evaluating age-related morphological changes that occur in the lumbar vertebrae.     

Three-Dimensional Morphological Analysis of Sex,Age, and Symmetry of Proximal Femurs from Computed Tomography: Application to Total Hip Arthroplasty

The success of a total hip arthroplasty is directly related to the ability of the implant to match original femoral morphology. Given this critical relationship, we characterized normal proximal femoral morphology as it relates to sex, age, and symmetry. Sixty abdominopelvic computed tomography (CT) scans (30 male and 30 female, ages 20–85 years old) from patients without any osseous pathology or implants were utilized. Three-dimensional models were constructed from the CT scans using Mimics v19 (Materialize). Thirteen landmarks were placed on each femur model and yielded eight morphological measurements for each femur. Medullary cavity measurements were taken superior to, at the center of, and inferior to the lesser trochanter. Morphological measurements were analyzed by sex, age group, and left versus right. A significant difference was identified between males and females for femoral head height, inferior neck length, minimum neck diameter, neck shaft angle, mediolateral medullary cavity measurement superior to the lesser trochanter and the anteroposterior at the lesser trochanter (P < 0.05). Age was found to correlate with medullary cavity measurements. As previously identified in the literature, differences with respect to the right and left femur were not of practical significance. The results show that sex is critical in determining prosthesis fit with the examined morphological measurements of the proximal femur while age is more important with respect to the medullary cavity. It is also evident that the current practice of using one femur to approximate the opposite is a viable clinical assumption. Clin. Anat., 33:731–738, 2020. © 2019 Wiley Periodicals, Inc.     

Growth of the second metacarpal according to chronological age and skeletal maturation.

In relation to chronological age and skeletal maturation, the growth of the second metacarpal is discussed based on radiographs of the right hand and wrist in 499 male and 424 female Japanese aged 1 to 18 years. When plotted against age, bone length and width present the general growth pattern of Scammon, the adolescent spurt occurring at about 13 years in the males and 11 years in the females, and the mean values are significantly larger in the males than in the females at age 15 years for length, and age 13 years for width, and later. The growth curves of both sexes are almost parallel to each other for bone length plotted against skeletal maturation. Bone width progresses in parallel in males and females until about adolescence, whereafter there is a more rapid increase in growth in the males than in the females. The mean values for length and width are almost always significantly greater in the males than in the females. The width/length index decreases rapidly until a certain period, the minimum value being at about ten years or a maturity corresponding to that age, and then increase slightly again to reach an equilibrium state on the basis of both age and skeletal maturation. At any given age, the mean values are always greater in the males than in the females. However, according to skeletal maturation, the sex differences are steadily significant at and after the skeletal maturity corresponding to about 12 years in the males and 10 years in the females.     

Growth of the second metacarpal according to chronological age and skeletal maturation

In relation to chronological age and skeletal maturation, the growth of the second metacarpal is discussed based on radiographs of the right hand and wrist in 499 male and 424 female Japanese aged 1 to 18 years. When plotted against age, bone length and width present the general growth pattern of Scammon, the adolescent spurt occurring at about 13 years in the males and 11 years in the females, and the mean values are significantly larger in the males than in the females at age 15 years for length, and age 13 years for width, and later. The growth curves of both sexes are almost parallel to each other for bone length plotted against skeletal maturation. Bone width progresses in parallel in males and females until about adolescence, whereafter there is a more rapid increase in growth in the males than in the females. The mean values for length and width are almost always significantly greater in the males than in the females. The width/length index decreases rapidly until a certain period, the minimum value being at about ten years or a maturity corresponding to that age, and then increase slightly again to reach an equilibrium state on the basis of both age and skeletal maturation. At any given age, the mean values are always greater in the males than in the females. However, according to skeletal maturation, the sex differences are steadily significant at and after the skeletal maturity corresponding to about 12 years in the males and 10 years in the females.     

Biological relationships and frontal sinus similarity in skeletal remains with known genealogical data

Frontal sinus analysis has potential utility for detecting biologically related individuals. However, the methodological approach to its evaluation, as well as its informative value, have been questioned. The aim of this work is to introduce a new approach to evaluating the frontal sinus using the ‘external supraorbital line’ (ESOL) and to determine whether there are sex differences within families in frontal sinus measurements and whether frontal sinus similarity reflects known genetic relationships in both measurements and morphology. We examined the skeletal remains of 41 adult individuals (25 males, 16 females), all members of one family over four generations (19th to 20th centuries), including individuals with very close consanguinity. CT images of skulls were acquired, and both the dimensions and morphology of the frontal sinuses were analyzed using their portions above the ESOL. No significant sex differences were found within families based on frontal sinus dimensions. Significant relationships were found between biological distance and the maximum height and morphology of the frontal sinuses. The greatest degree of similarity was found among closely related individuals. Additionally, in several cases, there was a greater degree of similarity between first cousins or grandparents and their grandchildren than among siblings or parents and their children. Total surface, volume and width are not significant indicators of relatedness. Known genetic relationships are also supported by individual morphological features. Variability within families with very close consanguineous relationships was lower than within families with common degrees of consanguinity, although differences are significant only for some variables.     

壮族人蛛网膜下池的CT观测

目的　获取壮族人蛛网膜下池的CT解剖数据及其变化规律。方法　对 2 5 4名健康壮族 (男 12 7,女 12 7)的头部CT片进行了测量 ,测量项目为 6项 ,并进行统计分析。结果　头部 6项指标平均值男大于女 ,性别差异有高度显著性。壮族脑池测量值 ,各年龄组间比较 ,大脑纵裂池和鞍上池各年龄组差异有显著性 (P <0 0 5鞍上池的 5 0～岁除外 ) ;环池除相邻年龄组间差异无显著性 (P >0 0 5 )外 ,各年龄组间均存在差异 (P <0 0 5 ) ;四叠体池 2 0～岁组与各年龄组及 30～组岁与 6 0～组岁间差异有显著性 ;大脑外侧窝池 5 0岁以前 3个年龄组间无显著性差异。结论　壮族人蛛网膜下池各年龄组间变化有自己的特点和一定的规律性 ;蛛网膜下池的解剖数据男大于女 ,存在性别差异     

Age and sex differences in bone density of the second metacarpal in its midshaft cross-section

On the basis of the midshaft cross-section of the second metacarpal in 102 male and 96 female Japanese, aged 30 to 98 years, age- and sex-related differences of bone mass and density are examined. Bone mass and density are almost always greater in males than in females. Cortical mass and apparent bone density decrease gradually with age after 45 years of age in both sexes. The decreasing rate is about twice as great in females as in males. The sex difference increases gradually with age, especially after the sixth decade. However, true bone density remains almost constant, regardless of age, until the seventh decade in both sexes. The maximum density layer is more deeply located at the radial side than at the ulnar, and also more so in males than in females, corresponding to the differences in cortical thickness. The relative depth of this layer to the bone width is about 15% at the radial side and 12% at the ulnar in males and about 12% and 10% at each side in females, respectively.     

正常成人锁骨形态的CT影像学研究

目的 观察测量锁骨CT影像学形态,为锁骨骨折锁定接骨板的治疗及改进提供解剖学参考。方法 回顾性研究2014年3—12月南京鼓楼医院排除锁骨骨折及其他可影响锁骨形态疾病的32例行肺部或颈部CT扫描患者的影像学资料,其中男16例,女16例;年龄20~75岁,平均年龄41.4岁。通过CT扫描及3D重建,分别测量32例64侧投影位锁骨的长度,近端、中段和远端宽度,锁骨近端和远端的曲率半径,锁骨水平面、冠状面的两端最大宽度及中间最小宽度等,采用成组t检验,分别比较不同侧别及性别间测量数据的差异。结果 男性锁骨的平均长度为(153.9±7.5)mm、女性锁骨的平均长度为(135.4±7.6)mm。男女的锁骨近端曲率半径均明显较远端曲率半径大,垂直投影的锁骨中段最小宽度男性为(11.7±1.9)mm,女性为(9.3±1.0)mm。左右侧各观察测数据差异均无统计学意义(P值均>0.05);男女性别间比较,除中远段曲率半径、中近段角度、中远段角度、冠状面近端最大宽度、上缘曲度差异均无统计学意义(P值均>0.05),其他指标差异均有统计学意义(P值均<0.05)。结论 锁骨的形态存在较大的性别差异,表现为女性锁骨的总长度及各部分长度较短、水平面和冠状面近端最大宽度较小,有必要根据性别差异改进器械;此外,测量结果还可为锁定接骨板术前预弯提供依据。     

Morphometric variations of the 7th cervical vertebrae of Zulu,White, and Colored South Africans

The 7th cervical vertebrae of 240 cadavers of South African Zulu, White, and Colored population groups were examined to determine morphometric variation. White and Colored females had statistically significant narrower cervical anteroposterior diameters than their male counterparts, whereas no statistically significant difference between sexes of the Zulu population group was observed in this variable. In addition, although Zulu and Colored females had statistically significant narrower cervical transverse diameters than their male counterparts, there was no statistically significant variation between South African white males and females in this respect. The findings indicate that sexual dimorphism is more apparent in the vertebral centrum, across the three population groups, where males had significantly larger dimensions in centrum anteroposterior diameter, height, and width than their female counterparts. The study further reveals that sexual dimorphism is more apparent when one compares aspects of the 7th cervical vertebra between sexes within the same population group. Overall, the dimensions of the various variates of the vertebra are substantially smaller in women than in men. The smaller dimensions, particularly of the centrum, may be the result of lower skeletal mass in women and render them more vulnerable to fractures resulting from compression forces. Clin. Anat. 23:399–406, 2010. © 2010 Wiley‐Liss, Inc.     

Growth and sexual dimorphism of the hyoid bone and its relationship to the mandible from birth to 19 years: A three-dimensional computed tomography study

The hyoid bone and the hyomandibular complex subserve the functions of respiration, deglutition, and speech. This study quantified the growth of the hyoid bone and the hyomandibular relationships in males and females from birth to 19 years. Using 97 computed tomography (CT) scans, from a previous study (Kelly et al., 2017) on mandibular growth from 49 individuals (16 with longitudinal scans), landmarks were placed on 3D CT models and used to calculate four distance, and three angular measurements. A general increase in growth trend was observed in hyoid bone linear measurements—length, width, and depth—as well as relational mandible-to-hyoid distance, throughout the developmental ages examined in both males and females, with most variables having larger measurements for females up to age 10 years. A general decrease in all three angular measurements was observed in both males and females up to approximately age 12 years, at which time male angular measurements gradually increased with significant sexual dimorphism emerging after age 15 years. As expected, postpubertal males had greater hyoid angle than females; they also had greater hyoid angle of inclination than mandible body inclination (with inclination relative to the anterior–posterior nasal plane), likely related to hyo-laryngeal descent. This study contributes to normative data on hyoid bone and hyomandibular relational growth in typically developing individuals and provides a baseline against which structural and functional influences on anatomic growth may be examined by clinical disciplines that address the aerodigestive and speech functions, as well as the fields of anatomy, forensics, and anthropology.     

Race and sex differences and contribution of height: a study on bone size in healthy Caucasians and Chinese.

Osteoporosis is characterized by a loss of bone strength, of which bone size (BS) is an important determinant. However, studies on the factors determining BS are relatively few. The present study evaluated the independent effects of height, age, weight, sex, and race on areal BS at the hip and spine, measured by dual-energy X-ray absorptiometry, while focusing on the differential contributions of height to BS across sex, race, and skeletal site. The subjects were aged 40 years or older, including 763 Chinese (384 males and 379 females) from Shanghai, People's Republic of China, and 424 Caucasians (188 males and 236 females) from Omaha, Nebraska. Basically, Caucasians had significantly larger BS than Chinese. After adjusting for height, age, and weight, the Chinese had similar spine BS, but significantly larger intertrochanter BS in both sexes and larger total hip BS in females compared with Caucasians. Males had significantly larger BS than females before and after adjustment in both ethnic groups. The effects of age, weight, and race varied, depending on skeletal site. As expected, height had major effects on BS variation in both sexes and races. Height tended to account for larger BS variation at the spine than at the hip (except for Chinese females), and larger BS variation in Caucasians than in Chinese of the same sex (except for the trochanter in females). We conclude that height is a major predictor for BS, and its contributions vary across sex, race, and skeletal site.     

A radiological method on the classification of human mandibular condyles

A radiological quantitative method applied in the classification of 210 mandibular condyles from 105 male and female subjects, aged 18-62 with no temporomandibular disorders has been taken up in this study. Through coronal sections, types of condyles were first determined by computer tomography (CT) per anterio-posterior aspects and then divided into four main groups described as flat, convex, angled and round. Then, using the parameters, every condyle type was divided into three subgroups. Finally, the percentage of each group has been estimated as follows: flat, 14.3%; convex, 35.2%; angled, 35.7% and round, 14.8%. When the condylar type was compared with sex, it was observed that the angled type (39.6%) in males and the convex type (40.3%) in females were higher than the other types. In the analysis of the relationship between age and condylar types, there appeared to be a trend toward an increase in the incidence of flat and a decrease in the incidence of convex with an increase in the age of males. In addition, following the determination of bilateral symmetry and asymmetry the bilateral asymmetry was determined to be higher in both sexes (56.2%).     

Morphometric characteristics of the sphenoid sinus and potential influencing factors: a retrospective assessment using cone beam computed tomography (CBCT)

The present study aimed to evaluate the morphological characteristics of the sphenoid sinus (SS), and the impact of potential influencing factors on the morphometric features using CBCT imaging. CBCT scans of 148 patients, aged between 15 and 85 (32.88 ± 15.33) years were retrospectively evaluated. DICOM files from the CBCT scans were imported into semi-automatic software and the SS of each patient was assessed for the morphological characteristics including configuration, symmetry, extension, shape, septation, volume, and maximum diameter. Furthermore, potential influencing factors such as age, gender, side, and sinus condition were analysed. A significant association was observed between sinus extension and age. Septation was also found to be significantly associated with age, gender and sinus condition. Besides, sinus volume was significantly associated with gender and sinus condition. No significant influence of shape and side on the morphometric features was noticed. The average volume and diameter of the SS were 6576.92 ± 3748.12 mm³ and 30.48 ± 9.28 mm, respectively. In conclusion, the present findings indicate that age, gender and sinus condition have a significant impact on the morphometric characteristics of the SS. Mature sinuses exhibit a post-sellar extension pattern until middle age. In addition, males, and sinuses with healthy sinus condition have larger volumes compared to females and pathological sinuses.

     

Sinus septi nasi: Anatomical study

The aim of this study was to perform a pioneering investigation into the incidence of pneumatization in human skulls. A total of 93 human skulls (≥20 years of age, 69 males, 24 females) were included in the study. The skulls were scanned in a fixed position using cone beam computed tomography (CBCT). The pneumatized space parameters within the nasal septum—width, length, and height—were measured. Two types of finding were identified: (a) Pneumatization, named “sinus septi nasi” (SSN), and (b) “spongy bone” (SB). The results showed SSN in 32 of the 93 skulls (34.4%). The SSN formations were from 0.5 to 4.2 mm wide, 3.5 to 18.8 mm long, and 3.8 to 17.7 mm high. Tumefactions filled with SB were found in 61 of the 93 skulls (65.59%). These were not suitable for precise measurements since the outer borders were not strictly and well defined on CT scans (perhaps because of the preparation process). In conclusion, the perpendicular plate of the ethmoidal bone is not always compact bone; in 34.4% of cases, it shows a degree of pneumatization. In contrast, an enlarged formation filled with SB is present in 65.59% of cases. The possible sources of pneumatization of this little‐investigated region are discussed: sphenoid sinus, frontal sinus, and vomeronasal organ. Clin. Anat. 30:312–317, 2017. © 2017 Wiley Periodicals, Inc.     

Sex differences in the genetic and environmental influences on the development of antisocial behavior

The present study uses a population-based sample of 6.806 adult twins from same-sex and opposite-sex twin pairs to examine sex differences in the underlying genetic and environmental architecture of the development of antisocial behavior (AB). Retrospective reports of AB during three different developmental periods were obtained: prior to age 15 years (childhood), age 15-17 years (adolescent), and age 18 years and older (adult). Structural equation modeling analyses revealed that there was no evidence for sex-specific genetic or sex-specific shared family environmental influences on the development of AB; that is, the types of genetic and environmental influence were similar for males and females. For both sexes, a model that allowed for genetic influences on adolescent and adult AB that were not shared with childhood AB fit better than a model with a single genetic factor. In contrast, shared environmental influences on adolescent and adult AB overlapped entirely with shared environmental influences on childhood AB. Genetic factors played a larger role in variation in childhood AB among females, whereas shared environmental factors played a larger role among males. However, heritability of AB increased from childhood to adolescence and adulthood for both sexes, and the magnitude of genetic and environmental influences on adolescent and adult AB was approximately equal across sex. We speculate that sex differences in timing of puberty may account for the earlier presence of genetic effects among females.     

Enlargement of the frontal sinus

The enlargement of the frontal sinus has been analysed in a longitudinal study of 49 males and 47 females for whom a first lateral cephalogram was available at from 2 to 5 years of age for 88 subjects and from 6 to 11 years for 8 subjects. Thereafter the cephalograms were taken at approximately yearly intervals and in 28 subjects a last cephalogram was taken at 24 years or older. In only six subjects was enlargement of the sinus still proceeding at the time of the last cephalogram . The enlargement was assessed by a standardized measurement of the maximum vertical height of the sinus. The median age for the first appearance of the frontal sinus was 3 X 25 years for the boys and 4 X 58 years for the girls. It enlarged on average to 32 X 60 mm (SD 9 X 10) in the males and 26 X 60 mm (SD 7 X 50) in the females. The median age at which the main increase in size of the sinus ceased was 15 X 68 years for boys and 13 X 72 years for girls, thus suggesting that the enlargement of the frontal sinus, a mainly osteoclastic activity, follows very closely the trends for growth in bone lengths.