Cone-shaped epiphyses in Japanese children

Cone-shaped epiphyses (CSE) are reported in left-hand radiographs of a sample of 1,399 otherwise normal Japanese children aged 5-11 years. CSE occurred in only three centers: distal thumb, mid-index finger, and mid-fifth finger. The overall frequency of 23% shows a female bias (32% to 16%), which disappears when mid-5 cones are excluded. Chi-squared analyses show significant gender bias for mid-5 cones alone or in combination with the other phalanges, and show significant center associations: CSE in distal-1 and/or mid-2 are more common in association with mid-5 cones than they are without mid-5 cones. The CSE female bias in mid-5 is essentially unchanged across age-cohorts when bone-age is controlled for precocity, and no significant trends in CSE frequency with age are noted for either gender.

Radiology of postnatal skeletal development. V. Distal humerus

Thirty-one pairs of distal humeri were obtained from human cadavers ranging in age from full-term neonates to fourteen years. These were studied morphologically and roentgenographically. Specimen roentgenography using air/cartilage interfacing demonstrated both osseous and cartilaginous components of the epiphyses. These roentgenographic aspects of development are discussed and illustrated to provide a basis reference index. The supracondylar region is characterized by a fossa which initially is in both metaphysis and epiphysis, but migrates to the metaphysis completely within the first year. On either side of the fossa are osseous columns, which contrast with the broad metaphyseal bone above the columns. Within the fossa, anteriorly and posteriorly, are fat pads which may be elevated by intraarticular hematoma or reactive joint fluid. The physeal contour initially is transverse and smooth. Lappet formation progressively demarcates the epicondylar physeal regions, with the medial one becoming a functionally, but not histologically separate region. The capitellum is the first region to develop a secondary ossification center. This progressively expands into the trochlear portion of the epiphysis, a factor which predisposes to lateral condyle fracture propagation across the trochlear articular surface. The trochlea characteristically ossifies by multiple foci which fuse over time, often creating an irregular appearance to the developing ossification center. Epicondylar ossification tends to be from solitary foci. The lateral epicondylar center fuses with the capitellar center, whereas the medial epicondyle tends to be functionally separate entity throughout development and does not normally fuse to the trochlear ossification center.

Growth behaviour of condylar cartilage and epiphyseal cartilage on the different medium of the organ culture

In order to compare histological differences between the condylar and epiphyseal cartilages, an organ culture system was employed. Materials from 36 neonatal rabbits were cultured for 7 days on three different, chemically defined media (Ham F12, Medium 199, and Eagle's minimum essential medium) with the addition of various concentrations of ascorbic acid, fetal calf serum and NaHCO3. The epiphyseal cartilage was maintained in situ histological and biochemical features better than the condylar cartilage on any of the medium used. The maximum sensitivity to Toluidine Blue staining of the cultured condylar cartilage was observed on Ham F12. For both the condylar and epiphyseal cartilages, Ham F12 with the addition of 50 microgram/ml ascorbic acid and higher concentration of NaHCO3 was more effective on the maintenance of cell organization. However, effect of the addition of fetal calf serum to the medium was quite different between the condylar and epiphyseal cartilages, that is, the former showed better histological features without the addition, but the latter showed features similar to that in situ with 20% addition of fetal calf serum.

Morphology of the perforating cartilage canals in the proximal tibial growth plate of the chick

Perforating canals arise exclusively from junctional canals just above the reserve zone and they do not branch after entering the proliferative zone. They are uniformly spaced and arranged in parallel array. The cartilage canals terminate near the beginning of the zone of hypertrophic cartilage cells. Vascular components within the perforating canals consist of a central arteriole surrounded by enlarged, interconnected capillaries which are individually in contact with the adjacent cartilage matrix. TEM shows that the capillary endothelium is extremely attenuated, possesses numerous fenestrations and lacks a continuous basement membrane. The central arteriole is enlarged through the midpart of the canal and then narrows to communicate with the capillaries near the bottom of the canal. The large capillaries ascend from their point of origin and recombine near the top of the growth plate to exit as a single venule. The vascular arrangement therefore describes a system in which the outgoing blood runs in close proximity, but counter to, the incoming blood. This vascular arrangement within the perforating cartilage canal would most likely allow the zone of maturing cartilage cells to receive the highest concentration of nutrients.

Some vagaries of the capitellum

The capitellum is the first epiphyseal center of the elbow to ossify. Its normal position is easily subject to misinterpretation as a separation fracture because: (1) the ossification center for the capitellum is situated anteriorly, (2) it is often tilted downward during development, and (3) its epiphysis tends to be wider posteriorly than anteriorly. The capitellum frequently fuses with the trochlea and lateral epicondyle before uniting with the humerus. We reviewed the normal anatomical configuration of the elbow. Some useful methods for evaluating the position of the normally situated and minimally displaced capitellum and distal end of the humerus are presented.

Correlation of lysozyme activity with proteoglycan biosynthesis in epiphyseal cartilage

Pig epiphyseal cartilage (proximal ulna epiphysis) previously incubated into vitro in the presence of sodium [35S]sulfate or [3H]thymidine was either analyzed by autoradiography or separated into 9 morphologically defined consecutive layers and investigated for 35S-incorporation into the guanidinium chloride-extractable proteoglycans and for lysozyme activity. The lowest 35S incorporation and lysozyme activity were determined in the zone of resting cells, but there is a consecutive increase in the rate of proteoglycan synthesis and lysozyme activity toward the diaphyseal cartilage-bone junction, with the maximum at the lower columnar cell zone and a sharp reduction of both parameters at the hypertrophic zone. The maxima of 35S incorporation and [3H]thymidine incorporation do not coincide. The guanidinium chloride-soluble proteoglycans exhibit macromolecular polydispersity. Fractions excluded from as well as retarded by Sepharose 2B gel could be separated and were detected in all zones. The results indicate a correlation of proteoglycan biosynthesis and lysozyme activity in epiphyseal cartilage.

The effect of dynamic loading on the growth of epiphyseal cartilage in the rat

The Hueter-Volkmann law of epiphyseal pressures describes an inverse relationship between static compressive forces parallel to the axis of epiphyseal growth and the rate of growth of that cartilage. Studies of histological sections of the epiphyseal plate of the fourth metatarsals of (a) control, (b) bipedal and (c) bipedal rats with amputation of the fifth metatarsal show that dynamic compressive forces can stimulate epiphyseal cartilage growth. Within certain parameters, both the relief and increase of dynamic compression accelerate epiphyseal growth. It is the amount and kind of loading that are important factors to accelerate epiphyseal growth.

The spherical index. A measure of the roundness of the femoral head

The sperical index is introduced as a new, simple method of measuring the roundness of the femoral head and capital epiphysis. The index may be applied both in children and adults. Means and standard deviations are presented for both sexes in different age groups. The index increases with age until maturation. In adults the index is constant.

Influence of growth hormone and thyroxine on endochondral osteogenesis in the mandibular condyle and proximal tibial epiphysis

Interrelationships of growth hormone and thyroxine effects on endochondral osteogenesis have been investigated. Evidence is offered that thyroxine augments the effect of growth hormone on the mandibular condyle just as at other osteogenetic centers, for example proximal tibial epiphysis in hypophysectomized rats. This contrasts with previous reports of a unique thyroxine antagonism to the effect of growth hormone on condylar development. In a further study on tibial epiphysis, special attention was given to assure absence of the endogenous thyroid hormone by adding thyroidectomy to hypophysectomy and reducing the possibility of thyroteopin residues in growth hormone. By histochemical tests, the responses of both calcified and noncalcified regions of the epiphyseal cartilage plate were measured. Graded growth hormone doses stimulated graded response in a noncalcified region. Thyroxine augmented this response eightfold. The width of the calcified region of the plate did not vary with treatment.

Trabecular architecture of the knee joint

The trabecular architecture of the human knee joint was studied three dimensionally by microradiography. The trabecular arrangement of the two condylar wheels of the femur was divided into five types. The trabeculae are so arranged that both condyles are able to adjust to mechanical compression and rotary movement. In the tibia, each trabecular arrangement has a different mechanical function. The epiphyseal line can be considered a laminated structure interposed between the compressive forces acting from the articular surface and the forces supporting the architecture of the metaphysis. The mechanics and kinematics of the traecular architecture are discussed.

Effect of strontium on the epiphyseal cartilage plate of rat tibiae-histological and radiographic studies

Following dietary administration of strontium carbonate, histological and radiographic changes in the epiphyseal cartilage plate of the rat tibiae were examined in the present study. The weight gain of the rat fed a strontium diet was less than that of the control rats. Longitudinal growth of tibiae and endochondral ossification were inhibited by strontium administration. The widths of both proximal and distal cartilage plates increased enormously as has also been shown by other investigators. Sizes of chondroblasts in columns of proximal cartilage plate in rats fed a strontium diet were smaller than those of the control rats and were not different between upper and lower parts. It is suggested that strontium inhibits bone growth through the inhibitory action on the maturation process of chondroblasts and the succeeding endochondral ossification.

Variations in the relationship between the diaphysis and the epiphyses of the tibia

In all 56 tibiae from Lapps and 56 tibiae from Norwegians have been studied. These ethnic groups represent different weight bearing situations. Variables expressing adaptation to non-axial loading are dealt with. The bone is mainly studied in the AP and the ML planes, as well as in the three dimensional space. The material is analyzed statistically. The distribution form is examined and the deviations from normality are found to be moderate. Mainly positive skewness occurs. Platykurtosis is found as often as leptokurtosis. The deviations from a standard normal distribution are not supposed to affect the results significantly. There is a non-systematic pattern of distribution. The variability is generally lower in Lapps than in Norwegians. The standard deviation shows highest numerical values in indices, lowest in linear variables. Systematic group differences, especially in similar variables, are supposed to be of greater importance than isolated differences. The variables giving deviations from the reference planes or the diaphyseal axis, show the largest and the consistent left-right differences. In linear variables Lapps and females show lower mean values than males and Norwegians, respecitvely. In linear variables giving deviations from the reference planes, in angular variables and in indices, Lapps usually show the highest mean values. Lapps tend to show larger sex differences in variables giving deviations from the reference planes or the diaphyseal axis. However, the sex differences within the Lapps are small. The variations of the tibia are supposed to be the results of mechanical factors in bone remodelling. The epiphyseal-metaphyseal parts tend to have a constant shape, the adaptations to non-axial loading predominantly appearing in the diaphysis. The relation between the weight bearing line and the diaphyseal axis is discussed, particularly regarding the ML stability mechanism of the knee joint. The occurrence of torsion and its influence upon the AP and ML projected values regarding the relationship between the epiphyses and the diaphysis are discussed.

Growth plate defects in foals

Local disorders of bone growth form an important group of the orthopaedic problems that occur in foals. The recognition of the condition presented is essential so that the appropriate corrective measures may be instituted, and an accurate prognostication made. A knowledge of the applied anatomy of the growth plate is essential to the understanding of these cases. Consideration is given to epiphyseal separation and to angular deformity, from the point of view of diagnosis, prognosis and treatment.

Shear strength of the human femoral capital epiphyseal plate

After the determination of the shear strength and modes of failure of the capital femoral epiphyseal plates in twenty-five pairs of hips obtained post mortem from children five days to fifteen years and ten months old, with the plate intact on one side and with the perichondrial fibrocartilaginous complex removed on the other, the gross and microscopic morphology was studied. The shear strength of the human epiphyseal plate varied with age and was greatly dependent on the surrounding perichondrial complex in infancy and early childhood, but less so in adolescence. When this complex was excised, the strength of the epiphyseal plate was diminished, especially in specimens from younger children. The forces necessary to cause slipping were found to be within the physiological range of the force that would be generated in overweight children, suggesting that purely mechanical factors may play a major role in the etiology of slipped capital femoral epiphysis.

The histology of epiphyseal union in mammals

Epiphyses of man and dog in various stages of union are described. As union approaches, new cartilage is added to the epiphyseal surface of the cartilaginous epiphyseal plate by chondrification of the epiphyseal marrow. Before and during early union the cellular arrangement of the cartilaginous epiphyseal plate is well preserved, with good cartilage columns. Mineralization of the cartilage, demarcated by tide-lines, spreads from both surfaces, engulfing the cartilage columns. The first union of an epiphysis is by such mineralized tissue, a form of metaplastic bone. In the smaller and earlier-uniting epiphyses, the mineralized cartilage and the sheets of lamellar bone that cover its surfaces are first removed in one restricted area and replaced by new bone and marrow. The original perforation is later enlarged until all the cartilage is destroyed and union in complete, leaving no scar. In the larger and later-uniting epiphyses there are multiple perforations in the epiphyseal plate and remnants of epiphyseal bone often persist as an epiphyseal scar. In both types of union remnants of the peripheral parts of the plates may be found for a while with the cartilage columns set at right angles to the axis of the bone as a whole, an unexplained peculiarity. At full union all such "residual" cartilage is destroyed.

Morphological studies of the canine intervertebral disc. The assignment of the beagle to the achondroplastic classification

The morphological development of the epiphyseal growth plate and intervertebral discs of newborn and nine-month-old beagles, greyhounds and dachshunds have been studied. On the basis of the cellular and matrix development of these canine tissues together with the known characteristics associated with achondroplasia it is concluded that the beagle should be assigned to the chondrodystroid breed classification.

Action of 1,25-dihydroxyvitamin D3 and a diphosphonate on calcium metabolism in rats

The effect of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) on Ca balance, 45Ca kinetics, and bone morphology has been studied in control rats and rats given disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP), 10 mg P/kg sc per day. This large dose of EHDP is known to inhibit bone mineralization and intestinal calcium absorption and to depress the endogenous production of 1,25-(OH)2D3. In conctrol rats, 1,25-(OH)2D3 increased intestinal calcium absorption. However, in contrast to the enhanced calcium absorption that results from an augmentation of dietary calcium, the 1,25(OH)2D3-induced augmentation of calcium absorption does not lead to a rise in calcium retention, the intestinal effect being matched by an increased excretion of urinary calcium. The EHDP-induced decrease of intestinal calcium absorption could be completely prevented by the concomitant administration of 1,25-(OH)2D3 but not the inhibition of bone mineralization. Therefore, in contrast to the impairment of calcium absorption, that of bone mineralization brought about by large doses of EHDP cannot be merely attributed to a decreased production of 1,25-(OH)2D3.

A system of grading ossification in limbs of foals to assist in radiologic interpretation

Tetracycline-labeled bones of 23 foals from 52 to 104 days old were sectioned and macroscopically examined to assess the extent of ossification or fusion of ossification centers. A grading system was devised with which to record information about the ossification centers and growth plates. The objective was to define anatomic standards which could contribute toward obtaining an accurate radiologic interpretation. Labeled limb bones of 3 neonatal foals were similarly treated, but grading of these was limited to the consideration of whether each site was still cartilaginous or had commenced to ossify.

The pseudoepiphysis of the first metacarpal of man

Images

Stimulation of bone resorption by increasing dietary protein intake in rats fed diets low in phosphorus and calcium

The effect of three levels (3.3, 11, and 33%) of dietary protein on bone resorption was studied in young rats fed diets deficient in P and Ca. Plasma P decreased and plasma Ca rose with an increase in dietary protein and returned to near normal values 8 h after food withdrawal. Urinary Ca rose linearly with increasing levels of dietary protein while urinary P was insignificant in the animals fed 11 and 33% protein. Assuming a molar ratio of Ca/P of 8.13/6 in young bones, estimates of the amount of P liberated from bone were calculated from urinary Ca and evaluated at 0.07,1.05, and 3.29 mg/100 g body weight per 8 h for the animals fed 3.3, 11, and 33% protein, respectively. Histological sections of the tibia revealed a progressive widening of the epiphyseal plate. Correlations between Ca excretion, levels of dietary protein, and width of epiphyseal plate were linear. Plasma P and Ca variations and Ca and P excretions in thyroparathyroidectomized and thyroxin replaced and in parathyroidectomized rats fed diets deficient in P and Ca containing 33% protein were similar to those of sham-operated controls. From this study we concluded that dietary protein independently of parathormone or calcitonin determines the magnitude of the physiological and histological changes observed in growing animals fed diets inadequate in P and Ca.

The germinal zone of the growth cartilage at the upper ends of the tibia and fibula in Gallus domesticus

Images