Epiphyseal Ossification Center Research Articles

Ultrasonographic Measurement of Distal Femoral and Proximal Tibial Epiphyseal Ossification Centers in the Third Trimester and their Correlation to Gestational Age

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Sonographic Identification and Measurement of the Epiphyseal Ossification Centers in the Prediction of Fetal Lung Maturity in Pregnant Egyptian Women

Sonographic Identification and Measurement of the Epiphyseal Ossification Centers in the Prediction of Fetal Lung Maturity in Pregnant Egyptian Women

Characteristics of the length of the radius and ulna in children.

ObjectivesCongenital malformation, trauma, tumor, or metabolic disease can cause length deformity of the radius or ulna, affecting the appearance and function of the forearm. Osteotomy and lengthening with external fixation can obviously improve the length of the radius and ulna (LRU). However, the extent of lengthening required is still unclear. This study analyzed the LRU in children, to provide suggested standards for various orthopedic treatments.MethodsNormal LRUs were measured on X-ray images in children who came to hospital for emergency treatment, with measurements including anterior–posterior (AP) radiographs, lateral (LAT) radiographs, full LRU (total length), and LRU without the epiphysis (short length). Any cases of fracture or deformity affecting measurement were excluded. Three hundred twenty-six cases were divided into 16 groups according to age from 1 year old to 16 years old.ResultsThe earliest epiphyseal plate and ossification center were observed in the distal part of the radius at 1 year old, and in the proximal part at 3 years old in both boys and girls. In the ulna, at the distal end it was 6 years old in girls and 7 years old in boys, while in the proximal part ossification was observed at 9 years old in both boys and girls. The proximal epiphyseal plate of the ulna began to close on X-ray images at 12 years old in girls and 13 years in boys. LRU increased with age, and there was a strong positive correlation and consistent ratio between radius, ulna and age. In short length, the ratio of the length of radius to ulna (RLRU) ranged from 0.8941 to 0.9251 AP, from 0.8936 to 0.9375 LAT. In total length, RLRU ranged from 0.9286 to 0.9508 AP, and 0.9579 to 0.9698 LAT.ConclusionsThe length and epiphyseal ossification of the radius and ulna are associated with age. RLRU is also limited to a certain range and tends to remain stable with age. These characteristics have clinical significance for deformity correction of the forearm.

Epiphyseal Ossification Centers as Predictor of Fetal Lung Maturity By Ultrasound

Epiphyseal Ossification Centers as Predictor of Fetal Lung Maturity By Ultrasound

The Relationship between Pulmonary Artery Doppler and Non-Doppler Sonographic Parameters in the Fetal Lung Maturity According to Gestational Age

Background: The evaluation of ultrasonic parameters of the lungs, especially the pulmonary arteries for gestational age, is still the first assessment of fetal lung maturity. We aimed to assess the relationship between pulmonary artery Doppler and non-Doppler sonographic parameters in the lung maturation of a fetus according to gestational age. Methods: This cross-sectional study was performed on pregnant women at different gestational ages that were indicated for Doppler ultrasonography as an indication for assessing fetal lung maturity. The correlation between non-Doppler sonographic indices and fetal pulmonary artery Doppler indices was evaluated. Results: Epiphyseal ossification centers, BPD, pulmonary echogenicity and free particles immersed in amniotic fluid were significantly higher in the group with a gestational age of 34 to 40 weeks than the group with a gestational age of 25 to 32 weeks. There was a significant difference in the mean of peak systolic velocity (PSV), ejection time (ET), acceleration time (AT) as well as acceleration time/ejection time (AT/ET) ratio between the two groups with a gestational age of 34 to 40 weeks and the group with a gestational age of 25 to 32 weeks. PSV, AT, ET, and AT/ET ration could predict fetal lung maturity with high sensitivity and specificity. Conclusion: With increasing gestational age, an increase in PSV, increase in AT, decrease in ET, and increase in AT/ ET indices are expected. In this regard, PSA, AT, ET, and AT/ET values are able to predict neonatal lung maturity with acceptable sensitivity and specificity.

Distal femoral epiphyseal ossification center absence in congenital syphilis: A case series.

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Statistical Confirmation of a Method of US Determination of Bone Age

Background There is limited literature on conventional US to assess bone age. Purpose To determine the diagnostic performance of US in the assessment of abnormal bone age in Chinese children. Materials and Methods In this prospective study, children and young adults aged between birth and 19 years from a large provincial teaching hospital were enrolled from January to November 2020. Children without clinical diseases potentially affecting skeletal growth were included in the normal-value group. Children with clinically suspected growth disturbances who were undergoing bone age evaluation were included in the validation group. Ossification ratios (ie, the ratio of the height of the epiphyseal ossification center to the entire epiphysis, including the cartilaginous component) of the radius, ulna, and femur from all the children were measured using US. Ultrasonic skeletal maturity scores (ie, the summation of ossification ratios of the radius, ulna, and femur multiplied by 100) collected from children in the normal-value group were used for score-for-age curve fitting through Box-Cox power exponential distribution. Test performance characteristics for the ability of US to help diagnose abnormal bone age were determined using radiographic bone age as a reference standard. Statistically significant difference between groups was determined by using a paired-sample t test. Results A total of 1089 children (median age, 9 years [interquartile range, 3-14 years]; 578 boys) were enrolled, including 929 children (mean age, 8 years [interquartile range, 4-12 years]; 515 boys) in the normal-value group and 160 children (mean age, 9 years [interquartile range, 7-11 years]; 63 boys) in the validation group. Ultrasonic bone ages in the validation group were evaluated with use of the lists of normal score-for-age values. With radiographic bone age as a reference standard, US could help diagnose abnormal bone age with high sensitivity (93% [14 of 15 participants; 95% CI: 66, 100] for boys, 100% [14 of 14 participants; 95% CI: 73, 100] for girls) and specificity (98% [47 of 48 participants; 95% CI: 88, 100] for boys, 98% [81 of 83 participants; 95% CI: 91, 100] for girls). Conclusion The US scoring system established can be used to evaluate bone age with high sensitivity and specificity. Clinical trial registration no. ChiCTR1900027917 © RSNA, 2021 Online supplemental material is available for this article.

Морфогенез енхондральних осередків окостеніння кісток пташенят спортивних голубів у ранньому постнатальному періоді онтогенезу

Racing pigeons are potential carriers of zooanthroponic diseases, since they can travel considerable distances during their flight. The study of the formation features of the pigeon skeleton’s hematopoietic function on different levels of its structural organization with the determination of the relationship between the growth and development of hematopoietic components and the processes of osteohistogenesis is necessary to understand the immunity of pigeons, especially during the early stages of their development when young animals are in the greatest risk of disease, especially during processes of osteogenesis and haematopoiesis in chicks. The bones of the axial and peripheral skeleton of one-day-old, 5-, 10-, 15-, 20-, and 25-day-old pigeons (n = 5) were examined. The presence and degree of development of dia- and epiphyseal ossification centers (EOCs), their relative area (RA) and X-ray density in the organs of universal hematopoiesis were determined on radiographs made on an x-Ray-TW-102 x-ray machine with an Alpha 4600 receiver using the MultiVox Dicom Viewer program. It was established that in day-old pigeons the rudiments of the studied bones are completely built by cartilaginous tissue, have low radiographic density, and fuzzy contours on radiographs. On the 10th day of life, the axial skeleton of pigeon cubs has formed EOCs of head and a tubercle on the 5th rib (third «true rib»), while in the bones of the peripheral skeleton there is an enchondral EOC of the diaphysis. The spongy and compact bone structure (BS) of the bones were fuzzy. The body of the rib and the epiphyses of the limbs’ tubular bones were cartilaginous. The X-ray density of the humerus at this age remains unchanged, and the tibial-metatarsal increases by 1.5 times, reaching 12 HU. In 15-day-old chicks, the RA of the EOC in the skeleton was moderately increased due to an increase in the RA of previously formed EOCs at the age of 10 days, the appearance of individual EOCs in the body of 5th rib, and in the tubular bones of the limbs, the enchondral EOCs of the proximal and distal epiphyses. In the diaphysis of the extremities tubular bones, a strip-like compact BS was clearly distinguished, and in the epiphyses, a small-sized spongy BS. The X-ray density of the bones almost doubled, reaching 19–21 HU. In 20-day-old pigeons, the processes of osteohistogenesis in the skeleton were almost completed, in the studied bones, all the main and additional EOCs were well expressed, their RA increased sharply. X-ray density of bones did not change. For 25-day-old pigeons in the skeleton, there was a slight increase in RA of the EOC, a process of complete synostosis of the bones was characteristic. From the moment of the appearance of the EOC in 10-day-old chicks until they reach the age of 25 days, the bones of the axial skeleton and the skeleton of the limbs were formed by 95–100% of BS, and their X-ray density was increased almost 2.5 times, reaching 19–26 HU.

Modified Serum ALP Values and Timing of Apparition of Knee Epiphyseal Ossification Centers in Preterm Infants with Cholestasis and Risk of Concomitant Metabolic Bone Disease of Prematurity.

The usefulness of serum alkaline phosphatase (ALP) and phosphorous in screening and monitoring of metabolic bone disease of prematurity (MBDP) still has some limitations, especially in preterm infants with concomitant conditions such as cholestasis. We aimed to assess a modification of serum ALP (M-ALP) as a biomarker for MBDP in preterm infants, and the use of ultrasound monitoring for the apparition of knee ossification centers as marker of bone mineralization. Biochemical and clinical registers were taken from 94 preterm newborns <32 weeks. A significant correlation existed between serum ALP and direct bilirubin (DB), expressed by the regression equation: M-ALP (IU/L) = 302.1 + 96.9 (DB (mg/dL)). The ratio ALP/M-ALP > 1 was demonstrated to be more specific (87.5%) in the diagnosis of MBDP than the cut-off value of serum ALP > 500 IU/L (62.5%). ALP/M-ALP > 1 showed 100% sensitivity and specificity for the diagnosis of MBDP, and a good correlation with specific bone ALP (B-ALP). Patients with the knee nucleus by post-menstrual week 37 had lower B-ALP compared to patients with no nucleus, and no patients with MBDP presented the nucleus by the 40th week. In the absence of reliable specific B-ALP, reinterpreting serum ALP values by M-ALP plus monitoring of knee ossification centers contribute to better management of MBDP in preterm infants with cholestasis.

The epiphyseal secondary ossification center: Evolution, development and function.

Bone age is used widely by pediatricians to assess the skeletal maturity of a child and predict growth potential. This entails measuring the size of secondary ossification centers (SOCs), which develop with age in the ends of long bones, which are initially cartilaginous. However, little is presently known about the developmental biology, evolution and functional role of these skeletal elements. Here, we summarize the knowledge currently available in this area and discuss potential primary functions of the SOC.

SONOGRAPHIC IDENTIFICATION AND MEASUREMENT OF THE EPIPHYSEAL OSSIFICATION CENTERS IN THE PREDICTION OF FETAL LUNG MATURITY IN EGYPTIAN WOMEN

Background: The most common cause of mortality and neonatal morbidity in preterm and early term fetuses is lung immaturity. Respiratory distress syndrome (RDS) is a major cause of neonatal mortality and morbidity where the lung cannot provide sufficient oxygen. Objective: Evaluating the distal femoral, proximal tibial and proximal humeral ossification centres as predictive tools of fetal lung maturity. Patients and methods: This study was conducted at Obstetrics and Gynecology Department, Damanhur Teaching Hospital, from May 2019 to January 2020 and included a sample of 100 pregnant women. The mean age of mother in our study was 25.35±3.75 years, the mean BMI was 32.85±4.33. The mean gestational age by U/S was 38.01±1.65 weeks, the mean epiphyseal ossification centers was ranged from 2.4-6.8 with a mean of 4.53±1.22, and the epiphyseal ossification centres were parallel to gestational age. Results: The results of this study showed that the relation between Mean Epiphyseal Ossification Centers and neonatal Respiratory distress syndrome. The mean Epiphyseal Ossification Centers were significantly low in neonatal with respiratory distress syndrome (p <0.05). It was found that there was a positive significant correlation between mean epiphyseal ossification centers and APGAR score at 5 min. It was found that the Mean Epiphyseal Ossification Centers were significantly increased with increasing gestational age. Conclusion: The distal femoral, proximal tibial and proximal humeral ossification centers have good predictive values of fetal lung maturity.

SONOGRAPHIC IDENTIFICATION AND MEASUREMENT OF THE EPIPHYSEAL OSSIFICATION CENTERS IN THE PREDICTION OF FETAL LUNG MATURITY IN EGYPTIAN WOMEN

Background: The most common cause of mortality and neonatal morbidity in preterm and early term fetuses is lung immaturity. Respiratory distress syndrome (RDS) is a major cause of neonatal mortality and morbidity where the lung cannot provide sufficient oxygen. Objective: Evaluating the distal femoral, proximal tibial and proximal humeral ossification centres as predictive tools of fetal lung maturity. Patients and methods: This study was conducted at Obstetrics and Gynecology Department, Damanhur Teaching Hospital, from May 2019 to January 2020 and included a sample of 100 pregnant women. The mean age of mother in our study was 25.35±3.75 years, the mean BMI was 32.85±4.33. The mean gestational age by U/S was 38.01±1.65 weeks, the mean epiphyseal ossification centers was ranged from 2.4-6.8 with a mean of 4.53±1.22, and the epiphyseal ossification centres were parallel to gestational age. Results: The results of this study showed that the relation between Mean Epiphyseal Ossification Centers and neonatal Respiratory distress syndrome. The mean Epiphyseal Ossification Centers were significantly low in neonatal with respiratory distress syndrome (p <0.05). It was found that there was a positive significant correlation between mean epiphyseal ossification centers and APGAR score at 5 min. It was found that the Mean Epiphyseal Ossification Centers were significantly increased with increasing gestational age. Conclusion: The distal femoral, proximal tibial and proximal humeral ossification centers have good predictive values of fetal lung maturity.

Prospects of circadian clock in joint cartilage development.

Altering the food intake, exercise, and sleep patterns have a great influence on the homeostasis of the biological clock. This leads to accelerated aging of the articular cartilage, susceptibility to arthropathy and other aspects. Deficiency or overexpression of certain circadian clock-related genes accelerates the cartilage deterioration and leads to phenotypic variation in different joints. The process of joint cartilage development includes the formation of joint site, interzone, joint cavitation, epiphyseal ossification center, and cartilage maturation. The mechanism by which, biological clock regulates the cell-cycle, growth, metabolism, and other biological processes of chondrocytes is poorly understood. Here, we summarized the interaction between biological clock proteins and developmental pathways in chondrogenesis and provided the evidence from other tissues that further predicts the molecular patterns of these protein-protein networks in activation, proliferation, and differentiation. The purpose of this review is to gain deeper understanding of the evolution of cartilage and its irreversibility seen in damage and aging.

The prediction of fetal maturity and gestational age by ultrasonic measurement of distal femoral epiphyseal secondary ossification center

Objective: The aim of this study was to determine the diameters of the distal femoral epiphyseal secondary ossification center (DFOC) in the various gestational ages (GAs) as well as to create a novel equation, through which GA can be calculated from the measurement of DFOC. Materials and Methods: EDAN Digital ultrasonic diagnostic imaging system (model DUS 3 made by EDAN, Korea) and a 3.5MHz Convex transducer were used for the sonographic measurement. Ultrasonographic examinations were performed on 999 normal singleton pregnancies with GAs ranging from the 28th to the 41st weeks. Patients were recruited from the University of Calabar Teaching Hospital to Assurance Medical Diagnostic Center, where the ultrasonographic examinations were carried out. Images of the long axis of the fetal femur were taken. The DFOC was visualized as a small echogenic, ovoid structure lying adjacent to the distal femur. Three measurements of the DFOC diameter (in mm) were taken from outer to outer margins, and the largest diameter was recorded. Other measurements obtained include femur length, abdominal circumference biparietal diameter, head circumference, fetal weight (FW), and GA. Results: DFOC increased with GA. A strong positive relationship was observed between DFOC and GA with a correlation coefficient of r = 0.85. DFOC also increased with FW with a correlation coefficient of r = 0.83. The equation (GA = 30.84 + [1.25 × DFOC in mm]) relates GA to DFOC. Conclusion: The diameter of the distal femoral epiphyseal secondary ossification center is a useful parameter for estimating GA and assessment of fetal maturity in the third trimester.

Osteochondritis Dissecans of the Humeral Trochlea: Characterization of a Rare Disorder Based on 28 Cases

Background: Osteochondritis dissecans (OCD) of the humeral trochlea is very rare. It may cause pain, mechanical symptoms, and loss of elbow motion, typically in the adolescent athlete. However, little published information is available regarding this condition. Purpose: To describe the clinical presentation, radiographic features, and prognosis of trochlear OCD. Study Design: Case series; Level of evidence, 4. Methods: Over a 10-year period, 28 patients presented to a tertiary pediatric hospital with trochlear OCD. Medical records and imaging were analyzed to characterize presentation, lesions appearances, and outcomes. Results: Mean ± SD age at presentation was 13.4 ± 1.6 years, and 13 of the 28 patients were male. The most common presenting symptom was pain (93%), followed by crepitus (54%). Evidence of trochlear OCD could be seen on initial radiographs in 94% of cases but was commonly missed. Coexisting capitellar OCD lesions were the most common associated abnormalities seen on magnetic resonance imaging (21%). Investigators noted 2 predominant patterns: “typical” trochlear OCD lesions (89%) were located on the lateral crista of the trochlea, 3.1 ± 4.4 mm lateral to the apex of the trochlear groove. This location corresponded to the medial tip of the capitellar epiphyseal ossification center and was not actually on the trochlear ossification center. “Atypical” trochlear OCD lesions (11%) were located more posteromedially. Trochlear OCD lesions in 4 elbows were managed surgically, while the remainder were managed nonoperatively. At mean ± SD follow-up of 13 ± 8 months, 12 patients (43%) were asymptomatic. A further 5 patients had ongoing crepitus but no pain (18%), and 4 patients (14%) underwent surgical treatment for their trochlear OCD (osteochondral fixation, n = 1; drilling/curettage, n = 3); 3 of the 4 patients experienced some improvement in pain. Conclusion: Although rare, trochlear OCD can cause considerable elbow problems. Clinicians should be aware of this differential diagnosis. Plain radiographs should be carefully scrutinized for subtle signs of trochlear OCD, particularly in the repetitive or overhead athlete with elbow pain. Although most patients’ symptoms will improve with activity modification, some may require surgery.

The missing segment of the autopod 1st ray: new insights from a morphometric study of the human hand.

Whether the 1st segment of the human autopod 1st ray is a 'true' metapodial with loss of the proximal or mid phalanx or the original basal phalanx with loss of the metacarpal has been a long-lasting discussion. The actual knowledge of the developmental pattern of upper autopod segments at a fetal age of 20-22 weeks, combined with X-ray morphometry of normal long bones of the hand in the growing ages, was used for analysis of the parameters, percentage length, position of epiphyseal ossification centers and proximal/distal growth rate. The symmetric growth pattern in the fetal anlagen changed to unidirectional in the postnatal development in relation to epiphyseal ossification formation. The percentage length assessment, the distribution of the epiphyseal ossification centers, and differential proximal/distal growth rate among the growing hand segments supported homology of most proximal segment of the thumb with the 2nd-5th proximal phalanges and that of the proximal phalanx of the thumb with the 2nd-5th mid phalanges in the same hand. Published case reports of either metanalysis of 'triphalangeal thumb' and 'proximal/distal epiphyseal ossification centers' were used to support the applied morphometric methodology; in particular, the latter did not give evidence of growth pattern inversion of the proximal segment of the thumb. The presented data support the hypothesis that during evolution, the lost segment of the autopod 1st ray is the metacarpal.

Accuracy Of Ultrasound Prediction Of Fetal Maturity By Ossification Center Of Long Bones in The Cases Of Elective Cesarean Section At 38 Week Gestation

Fetal lung maturity can be assessed by biochemical analysis of amniotic fluid, but it carries the potential for serious complications of amniocentesis .Efforts have been made to use prenatal diagnostic ultrasonography as a means of evaluating lung maturity. Ultrasonography, a non invasive and widely available method, would be more acceptable.Objective: The aim of this study is to determine accuracy of sonographic prediction of fetal maturity by ossification center of long bone(femur ,tibia and humerus) ,to determine most accurate one in estimation of gestational age(GA) at 38 weeks to do elective cesarean section and evaluate if gestational age by obstetric ultrasound is corresponding to evaluation by neonatology specialist. Methods: The study was conducted on 200 pregnant woman were delivered by elective cesarean section in General Monof and AL-Zahraa University Hospitals in the period from Februrary2017 to August2017.All the mother where subjected to full history, examination(general-local),ultrasound examination for detection of(GA) by fetal biometry ,visualize and measure proximal ossification center of (tibia, humerus) and distal(femur).Then reassessment of (GA)and fetal maturity after delivery by neonatology specialist .We have 2 groups (mature &immature) fetus according to(GA) of neonates , Apgar Score and the need of the neonates to NICU. Results: We studied prospectively 200 pregnant women scheduled for elective cesarean section at 38 wks gestation and compared the sonographicepiphyseal findings with the results showing after delivery. we found 187 mature fetus with mean age (38)wks and 13 immature fetus with mean age(36 wks ) admitted in NICU. Immature group having distal femur epiphysis(DFE) (13/13) and proximal tibia epiphseal (PTE) ossification present in (12/13cases)but absent in(1/13)case while Proximal ossification center of humerus (PHE) was absent in (0/13) immature fetus but(PHE) was present in 168 and absent in19 maturefetus. While ossification center of femur and tibia present(187/187) mature fetus. Using cut off point of size distal Epiphyseal Ossification Center(EOC) of femur ( 6.25mm) or more as good predictor of fetal maturity with sensitivity of 86.1% & specificity of 70.4%&area under the curve0.878.While cut off point of size proximal (EOC) of tibia( 38)gestation but its absence not indicate fetal immaturity because it was absent in 19 case of mature fetus ,so can depends on size of distal (EOC) of femur >( 6.25mm) and total size of(EOC) of 3 long bones >14mm , as tool for estimating of fetal maturity in the absence(EOC) of humerus. Conclusion: Confirmation of fetal maturity obtained by fetal biometry and ultrasound visualization and measurement of size of the epiphyseal ossification centers of long bones (femur-tibia-humerus) can be used as a tool for estimation of fetal maturity at 38 wks before elective cesarean section.

The prevalence and ossification pattern of the biphalangeal and triphalangeal lateral toes

PurposeBiphalangealism of the toes is an exclusively human phenomenon. The aim of this study was to evaluate the development of the lateral toes in childhood by following the ossification pattern of the phalanges.MethodsFoot radiographs of 913 adults have been evaluated for biphalangealism of 3rd to 5th toe. The pediatric group, aged 6–15 years of age, was assessed for the number of ossification centers in the foot.ResultsIn adults, the mean prevalence of biphalangealism in the 5th toe was 41.39%, in the 4th toe was 2.15%, and in the 3rd toe was 0.48%. In children, 45% feet had four ossification centers in the 5th toe. The epiphysis center of the middle and distal phalanx was missing. In the 4th toe, four centers were present in of 2.47% of cases. Those values are similar to the prevalence of the biphalangeal toes in adult population. The remaining toes had 5 or 6 ossification centers. In the 5-center toe, the epiphysis of the middle phalanx was missing.ConclusionA missing distal phalanx epiphyseal ossification center is considered indicative of a biphalangeal toe, and the toes with 5 or 6 ossification centers are indicative of triphalangeal toes. The reason for such evolution of the lateral toes is still debated, but the differences in anatomy most likely have no impact on foot function.

The completely fused medial clavicular epiphysis in high-frequency ultrasound scans as a diagnostic criterion for forensic age estimations in the living.

The assessment of ossification of the medial clavicular epiphysis plays a decisive role in the forensic age estimation of living subjects. Primarily for reasons of minimizing the radiation exposure currently associated with such evaluations, non-ionizing methods would be an advance.This study pursued the question whether full union of the medial clavicular epiphysis, visualized by high-frequency sonography, is a reliable criterion for age-threshold determinations. The ossification stage of the medial clavicular epiphysis of 215 female and 195 male volunteers, aged between 14 and 26years, was evaluated in bilateral sonograms. Stage 4, defined as complete fusion by Schulz et al. (Int J Legal Med 122:163-167, 2008), was observed on at least one body side in 48 of 334 individuals younger than 21years (14.4%) and in 32 of 264 individuals younger than 18years (12.1%).With the high-frequency ultrasound used in this study, even the smallest convexities of the medial clavicular ending can be visualized. This may have led to overestimation of the ossification stage. It is not clear whether any observed roundings in the sonograms should actually be interpreted in terms of stages 3 and 4 as defined by Schulz. Also, due to the low penetration depth of high-frequency ultrasound waves, epiphyseal plate residues and ossification centers may have remained undetected. Reliable differentiation of the stages 1-4 with high-frequency sonography is thus difficult, and the results suggest that this method is not a radiation-free alternative to computed tomography, the current gold standard for determining age thresholds.

Relationship between the chondrocyte maturation cycle and the endochondral ossification in the diaphyseal and epiphyseal ossification centers.

The chondrocyte maturation cycle and endochondral ossification were studied in human, fetal cartilage Anlagen and in postnatal meta-epiphyses. The relationship between the lacunar area, the inter-territorial fibril network variations, and calcium phosphorus nucleation in primary and secondary ossification centers were assessed using light microscopy and scanning electron microscopy (SEM) morphometry. The Anlage topographic, zonal classification was derived from the anatomical nomenclature of the completely developed long bone (diaphysis, metaphyses and epiphyses). A significant increase in the chondrocyte lacunar area was documented in the Anlage of epiphyseal zones 4 and 3 to zone 2 (metaphysis) and zone 1 (diaphysis), with the highest variation from zone 2 to zone 1. An inverse reduction in the intercellular matrix area and matrix interfibrillar empty space was also documented. These findings are consistent with the osmotic passage of free cartilage water from the interfibrillar space into the swelling chondrocytes, which increased the ion concentrations to a critical threshold for mineral precipitation in the matrix. The mineralized cartilage served as a scaffold for osteoblast apposition both in primary and secondary ossification centers and in the metaphyseal growth plate cartilage, though at different periods of bone Anlage development and with distinct patterns for each zone. All developmental processes shared a common initial pathway but progressed at different rates, modes and organization in diaphysis, metaphysis and epiphysis. In the ossification phase the developing vascular supply appeared to play a key role in determining the cortical or trabecular structure of the long bones. J. Morphol. 277:1187-1198, 2016. © 2016 Wiley Periodicals, Inc.