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At least 19 recordsLinked to original sources
PubMed1991

Metaphyseal anadysplasia: a metaphyseal dysplasia of early onset with radiological regression and benign course.

We report on 4 boys (including 2 maternally related first cousins) with a metaphyseal dysplasia of early onset and regressive evolution. Diagnosis is possible in the first months. Distal metaphyses of long bones are very irregular. Femoral necks seem hypoplastic and the edges of the metaphyses are almost vertical; femoral shaft is bowed. Those anomalies disappear after 2 years. The main manifestations are slight shortness and a light varus deformity of the lower limbs. Stature is not affected. The upper tibial growth cartilage, studied in one case, showed wide proliferative and hypertrophic zones with an unusual appearance of the last hypertrophic cells and an abnormal zone of cartilage calcification and resorption. The name "metaphyseal anadysplasia" is suggested for this early and regressive disorder. We are aware of other forms of regressive metaphyseal dysplasia which deserve further delineation. Therefore infants whose radiological changes of metaphyseal dysplasia do not fall into one of the well-defined types should be followed and prediction of the adult height should not be made on the basis of the findings on the initial examination.

Bone Diseases, Developmental↗
PubMed1992

The fibrous metaphyseal defect in early stage. Differential diagnosis to metaphysitis.

In a 22-month-old boy a fibrous metaphyseal defect (FMD) was diagnosed by radiological follow-up examinations. The initial radiological finding could not be differentiated from metaphysitis because of its early manifestation and stage. Eleven months later, magnetic resonance imaging (MRI) with Gadolinium (Gd)-DTPA demonstrated a small central area of increased signal intensity. Based on known angiographic findings with fibrous metaphyseal defects, one may hypothesize that this is best explained by a hypervascularized area.

Bone Diseases, Developmental↗
PubMed1991

Metaphyseal acroscyphodysplasia.

Based on two independent personal cases and a pair of sibs from the literature, we delineate a new category of bone dysplasia with cup-shaped large metaphyses, for which the name metaphyseal acroscyphodysplasia is suggested. The main clinical features are severe growth retardation, micromelia predominating in the lower limbs, knee flexion, and severe brachydactyly. The radiological aspect of the knees is very specific: the lower femoral and upper tibial epiphyses embed themselves in their metaphyses, which are severely cup-shaped. Premature central epiphyso-metaphyseal fusion and gross deformation, or even coalescence, of the femoral condyles may occur. The femoral diaphyses are very short and broad, and there is progressive coxa valga. Bowed and/or short stubby tibiae with cone-shaped metaphyses, and varus deformity of the tibio-astragalian joint are other features. Slight deformations of the long bones occur in the upper limb. Severe brachydactyly, brachymesophalangy, phalangeal and metacarpal cone-shaped epiphyses and irregular, bent and shortened diaphyses are the main signs of hand involvement. Psychomotor retardation is present in 3/4. Autosomal recessive inheritance is likely.

Bone and Bones↗
PubMedDate not supplied

Metaphyseal and spondylometaphyseal chondrodysplasias.

Diseases characterized by defective metaphyseal ossification, (metaphyseal chondrodysplasias) and defective spinal and metaphyseal ossification (spondylometaphyseal chondrodysplasias) constitute an important group of congenital intrinsic diseases of bones in which orthopedic treatment is of utmost interest. The most common types of metaphyseal chondrodysplasias (Jansen, Schmid, McKusick, and Metaphyseal Chondrodysplasia with Pancreatic Insufficiency and Neutropenia) and spondylometaphyseal chondrodysplasias (Kozlowski) have characteristic well-defined diagnostic features. The importance of proper diagnosis for practical reasons--appropriate medical and psychological treatment, professional training and genetic counseling--cannot be overemphasized. Elucidation of the pathogenesis in this group of diseases is bound to emerge from future histochemical and biochemical research.

Adolescent↗
PubMedDate not supplied

"Metaphyseal" cysts in Legg-Calve-Perthes' disease.

Radiographic changes in the femoral metaphysis in Legg-Calve-Perthes' (LCP) remain poorly understood. Our hypothesis was that these "cysts" are not truly metaphyseal but are metaphyseal changes radiographically projected onto the metaphysis. Surface epiphyseal changes were made on a normal hip and a hip with LCP. These "lesions" appeared metaphyseal on radiograph, and in the specimen with LCP, projected deep within the metaphysis due to flattening and three-dimensional distortion. "Metaphyseal" cysts in LCP may be epiphyseal changes superimposed on the metaphysis. This would explain the correlation between the presence of a "metaphyseal" lucency and final result, since it is simply another indicator of the extent of epiphyseal involvement.

Bone Diseases↗
PubMed1990

Biomechanical factors in the metaphyseal- and diaphyseal-lengthening osteotomy. An experimental and theoretic analysis in the ovine tibia.

A post hoc comparison of the mechanical factors that affected the outcome of experimental metaphyseal- and diaphyseal-lengthening osteotomies in sheep tibiae was performed. The resulting motions between bone segments at the metaphyseal and diaphyseal levels were estimated using measured fixator stiffnesses, postural muscle activity, ground reaction forces, and calculated internal and external loads. Relative displacements of bone segments of up to 2.8 degrees were estimated in postural activities; displacements were up to 4.9 times larger at the metaphyseal than at the diaphyseal osteotomy level. The results suggest that due to these increased motions, mechanically inferior conditions for healing at the metaphyseal-lengthening osteotomy level may counteract any supposedly superior biologic healing potential that the metaphyseal region of the bone may have compared with the diaphyseal region. These results correlate well with the clinical findings of the earlier animal study.

Animals↗
PubMed1989

[Radius-femoral dysplasia. A new form of hereditary metaphyseal dysplasia].

Höhle and Braun described a new form of hereditary metaphyseal dysplasia. It is characterized by changes in distal metaphyses of femoral bones which are formed as Erlenmeyer flasks, further by club-shaped dysplasias of the metaphyses of the other long bones, absence of skeletal hyperostosis and by characteristic varus-deformations of radial bones. An extensive family history research showed that the oldest carriers of these anomalies came from a small town in northern Bohemia. Completely identical case reports were published describing the carriers of metaphyseal dysplasia characters whose origin was also traced to the same region. The authors aim at drawing attention to this new disease, finding more carriers of metaphyseal dysplasia characters and at giving an impulse to an extensive research into this extremely systemic rare bone disease.

Adult↗
PubMed1991

Rearrangement of the metaphyseal vasculature of the rat growth plate in rickets and rachitic reversal: a model of vascular arrest and angiogenesis renewed.

The morphology of the metaphyseal microvasculature at the epiphysis was examined at both the light and electron microscopic level in rickets and rachitic reversal. The animals studied were normal, rachitic, and rachitic reversed at 8, 24, and 96 hours post-vitamin D administration. The overall architecture of the metaphyseal vessels was significantly altered throughout the intervals examined. In the rachitic animal, arterioles, venules, and capillaries were found adjacent to the growth plate, either directly apposed to the hypertrophic chondrocytes or separated from them by bone-forming cells. These vessels are in many ways similar to the larger arterioles and venules that normally supply the metaphyseal capillary sprouts, but in the normal growing animal are usually located 350-500 microns from the epiphyseal cartilage. The rachitic capillaries appear relatively well differentiated with a partial basement membrane and a perivascular cell lining. In early rachitic reversal, small vascular projections are induced to grow from the large diameter venules that border upon the hypertrophic chondrocytes. These vascular sprouts that invade the epiphyseal cartilage are quite undifferentiated, with no basement membrane or pericyte lining at the sprout apex and occasional abluminal endothelial cell projections. Within 96 hours, the metaphyseal microvasculature has returned to an apparently normal state with only capillaries at the cartilage-vascular interface and larger vessels (arterioles and venules) located several hundred microns deeper into the metaphysis. The sequential processes of differentiation and cessation of capillary growth followed by dedifferentiation and reinitiation of microvascular growth make the rachitic system a unique one in which to study angiogenesis.

Animals↗
PubMed1989

Fibrous metaphyseal defects. Magnetic resonance imaging appearances.

Sixteen patients with fibrous metaphyseal defects were examined with both plain radiography and magnetic resonance (MR) imaging. Depending on the age of the fibrous metaphyseal defects, characteristic radiomorphologic changes were found which correlated well with MR images. Following intravenous Gadolinium-DTPA injection, fibrous metaphyseal defects invariably exhibited a hyperintense border and signal enhancement. Healed lesions exhibited a transition to normal bone marrow. A line through the maximum longitudinal diameter of a fibrous metaphyseal defect invariably led to a point of tendinous or ligamentous insertion. Coronal MR images demonstrated the maximum longitudinal extension and the respective inserting tendon or ligamentous structure at the epiphyseal line.

Adolescent↗
PubMedDate not supplied

Capital necrosis, metaphyseal cyst and subluxation in coxa plana.

Three specific elements associated with a poor prognosis in Legg-Calvé-Perthes disease, i.e., capital necrosis, metaphyseal cyst and subluxation, have been selected for study to determine the effect of each on the end result. A retrospective analysis was made of 337 children who received non-weight-bearing treatment. Half of the patients were treated in abduction splints, over a third with bed rest and traction and the remainder with a variety of routines including sling and crutches, wheelchair or bed rest alone. The group was treated as representing a common pool of therapy and was analyzed statistically in this overall manner. End results were graded by the Knud Mose method (concentric circle matching plus epiphyseal quotient determinations). Good and fair results were combined into an acceptable category while the poor results were considered unacceptable. Femoral capital necrosis was present either segmentally or totally. A classification was devised of three grades of partial epiphyseal involvement and one of total necrosis. The patients with total necorsis (Group IV) had a higher percentage of poor results than those with segmental involvement (Groups I, II and III). The lowest percentage of poor results correlated with the least involvement of the femoral head (Group III). Total head involvement occurred in the unacceptable group one and one half times as frequently as it did in the acceptable group. Metaphyseal cyst formation exhibited a close relationship to the fragmentation of the capital epiphysis. It is suggested that the metaphyseal lesion itself is part of the overall necrotic process and that the "cyst" is resorption associated with revascularization as healing is taking place. We noted twice the frequency of metaphyseal cysts in patients with poor results in comparison to that found in the acceptable group. Subluxation is defined as loss of acetabular centration of the femoral head due to upward and outward displacement. Increased distance between the medial margin of the metaphysis and the lateral limb of the "tear drop" figure is practically a universal finding on early roentgenograms and was not considered "subluxation" in this prognostic evluation. In the series under study there were three times as many subluxations in the poor result group as in the group with acceptable results. A prognostic profile revealing three of the above-listed features was associated with a poor result and should constitute an objective basis of evaluation of new forms of therapy.

Bone Cysts↗
PubMed1992

Limb deformity and metaphyseal abnormalities in thalassaemia major.

Regular bone survey radiographs have allowed identification of limb deformity and metaphyseal changes in several patients with thalassaemia major treated at the Adelaide Children's Hospital. Following the progression of limb deformity in five of these patients who were receiving human growth hormone therapy, the records of 25 thalassaemia patients were reviewed. Six patients had evidence of limb deformity, four of whom also had metaphyseal changes. Three additional patients had metaphyseal changes alone. Patients with either type of skeletal change shared similar characteristics, including younger age, earlier commencement of desferrioxamine therapy, better compliance and, in general, lower levels of ferritin. Females predominated in both groups. The frequency of sensorineural hearing loss was similar in affected and nonaffected groups and biochemical parameters, especially plasma calcium, phosphate, alkaline phosphatase, and zinc, which were normal in all patients. The cause of these skeletal changes is not clear; however, several potential factors need to be considered. Among these are focal marrow expansion in the metaphyseal region due to incomplete suppression of erythropoiesis and possible effects of desferrioxamine, including direct interference with bone growth, altered response of bone to inflammation or infection, and altered bone metabolism related to chelation of trace metals. While we can only speculate on aetiological factors, it is clear that human growth hormone therapy has resulted in exaggeration of deformity due to an increased rate of bone growth or decreased rate of mineralization of physeal cartilage. We believe that bone survey radiographs are useful in early identification of skeletal changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Dense metaphyseal bands and growth arrest associated with isotretinoin therapy.

A 9-year-old boy, treated with high-dose isotretinoin therapy for fibrodysplasia ossificans progressiva, developed dense metaphyseal bands and growth arrest. Discontinuance of isotretinoin therapy was followed by gradual decrease of metaphyseal bands and resumption of clinical growth. The dense metaphyseal bands may be related to the known action of retinoids as modulators of chondrocyte phenotype and gene expression.

Adolescent↗
PubMed1990

Vascular invasion of the epiphyseal growth plate: analysis of metaphyseal capillary ultrastructure and growth dynamics.

Metaphyseal blood vessels which invade the calcifying epiphyseal growth plate were examined by a variety of techniques to determine their morphology, cell division, and growth patterns as they relate to endochondral ossification. Four regions of these vessels were characterized: 1) sprout tips--the terminal ends of the capillary sprouts which impinge upon the hypertrophic chondrocytes of the growth plate; 2) region of extended calcified cartilage--those deeper vessels within the metaphysis which are surrounded by an extracellular matrix predominantly composed of extended septa of calcified cartilage; 3) region of bone deposition--further still from the epiphysis these microvessels are contained within a network of active bone deposition laid upon a scaffold of calcified cartilage; 4) region of primary vessels--at a distance of 350-500 microns from the epiphysis are dilated vessels with one or two layers of smooth muscle in their walls, which supply and drain the metaphyseal capillary plexus. The sprout tips are continuous blind-ended vessels lined with an attenuated endothelium with no underlying basement membrane. Dividing endothelial cells are most frequently found in the region of bone deposition 175-200 microns behind the apices of the growing sprout tips. A time-coursed, autoradiographic examination of cytokinesis revealed radio-labelled endothelial cells to appear at the epiphysis after a 24 hr period. The metaphyseal capillary sprouts represent a continuous, unidirectional angiogenic vascular network which grows by elongation from the region of bone deposition; this region remains a fixed distance behind the sprout tips. These findings are discussed in light of the growth dynamics between this vascular plexus and the epiphyseal growth plate.

Animals↗
PubMed1991

Evaluation of orthogonal mechanical properties and density of human trabecular bone from the major metaphyseal regions with materials testing and computed tomography.

We evaluated the orthogonal mechanical properties of human trabecular bone from the major metaphyseal regions with materials testing and quantitative computed tomography (CT). The proximal tibia, distal femur, proximal femur, distal radius, and proximal humerus from fresh cadaver specimens between the ages of 55 and 70 years were excised and prepared for experimentation. The bones were embedded and scanned at 1 or 1.5 mm intervals on a Technicare HPS 1440 and GE 9800 CT scanner. After scanning, the bones were sectioned, producing 8-mm cubes of trabecular bone which were mechanically tested in uniaxial compression at a strain rate of 1%. The testing sequence consisted of preyield tests in two of the three orthogonal directions and failure in the third. After testing, the cubes were evaluated for apparent density and ash weight. The results of the study show that the strength and stiffness of trabecular bone varies significantly within metaphyseal regions and from metaphysis to metaphysis. The power and significance of relationships between density and modulus varied as a function of metaphyseal location. Both linear and nonlinear models were significant, suggesting that trabecular deformation occurs in response to both axial and bending loads. Finally, the need for architectural measures of trabecular bone to predict mechanical properties is emphasized.

Aged↗
PubMed1987

Loss of proteoglycans during decalcification of fresh metaphyses with disodium ethylenediaminetetraacetate (EDTA).

Recent immunofluorescent and histochemical data did not detect changes in the concentration of proteoglycans between noncalcified and calcified cartilage in fetal bovine growth plate or metaphyseal bone. These findings were constant, regardless of prior fixation before demineralization with disodium ethylenediaminetetraacetate (EDTA) or prior demineralization before fixation. Previous experience has shown that EDTA can extract proteoglycans from calcified cartilage. With this in mind, we determined the amount of proteoglycan extracted from calcified cartilage in metaphyseal bone and uncalcified growth plate cartilages during decalcification of unfixed fresh tissues with EDTA. To this end, fresh growth plate cartilages and metaphyses were decalcified at 5 degrees C for 48 hours in a buffered solution of EDTA to which several protease inhibitors were added. Under these conditions 20-25% of the total proteoglycan (measured as uronic acid and hexosamine) was extracted from mineralized cartilage but only about 1% from the uncalcified (growth plate) cartilages. Thus, histochemical and immunohistochemical studies appear to be insensitive measures of proteoglycan concentrations in histological sections of mineralized tissue and may not give quantitative information.

Animals↗
PubMed1990

Microspherophakia-metaphyseal dysplasia: a 'new' dominantly inherited bone dysplasia with severe eye involvement.

We report a father and son affected by a hitherto unpublished bone dysplasia with moderately severe dwarfism. On initial radiographs, thickening of the diaphyses of the long bones was striking. The small bones of the extremities were almost unaffected. With age, the metaphyseal deformation became more prominent. The epiphyses became irregular and their growth was delayed (particularly the femoral heads). The femoral neck showed an unusual 'lip' on the inner edge. Later, the stubby appearance of the long bones faded and, in adulthood, only enlarged metaphyses and deformed femoral necks persisted. The vertebrae showed moderate deformation with irregular flattening, and narrowing of the spinal canal with a shortened interpedicular distance. The eye defects consisted of high grade myopia, microspherophakia, lens coloboma, lens luxation, and retinal detachment. The name 'microspherophakia-metaphyseal dysplasia' is suggested for this probably autosomal dominant bone dysplasia.

Adult↗