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Spondylo-epi-metaphyseal dysplasia with normal stature: a case followed from infancy to skeletal maturity.

Spondylo-epi-metaphyseal dysplasia is a rare skeletal dysplasia showing radiographic abnormalities in the epiphyses and metaphyses of the long and short tubular bones, and in the spine. There are very few reports of a case followed throughout the entire growth period. Here we report the case of a Japanese girl followed from 1 month old to skeletal maturity at 16 years old. She developed progressive kyphoscoliosis at 7 years old, and underwent a surgical correction of the spine at 14 years old. The diagnosis of spondylo-epi-metaphyseal dysplasia was made from examining all the follow-up radiographs showing abnormalities in the spine, long bones and hands involving epiphyses and metaphyses. She had normal stature--a rare finding in this condition.

Adolescent↗

Osseous integration of hydroxyapatite grafts in metaphyseal bone defects of the proximal tibia (CT-study).

PURPOSE OF THE STUDY: The purpose of the study was the examination of the osseous integration of hydroxyapatite grafts used for the filling of metaphyseal bone defects in tibia head fractures. MATERIAL: Four patients with lateral tibia plateau fractures AO-type B3 (12) were included in the study. Patients were treated by arthroscopically assisted reduction and percutaneous screw fixation. The metaphyseal bone defects were filled with prepared solid hydroxyapatite graft blocks (Endobon Fa. Merk Darmstadt, Germany). In all of the patients a CT study for the osseous integration of hydroxyapatite grafts used for the filling of metaphyseal bone defects in tibial head fractures was performed. Measurements of density were performed of the implant region, the periimplant region, the distant periimplant region and the fibula bone. Follow-up CT examinations of these specific regions were performed 6 and 12 months postoperative. RESULTS: In all cases an increase of density of the hydroxyapatite graft after 6 months and 12 months follow-up was detected. The periimplant region showed in all cases a decrease of density. A progressive decrease of the periimplant and the distant cancellous tibial bone region was also detectable after 6 and 12 months post-op. A similar decrease of density was visible in the region of the cancellous bone of the fibula. In the interface region a direct bone formation between the hydroxyapatite graft and the adjected cancellous bone was visible in all cases during follow-up. CONCLUSION: The increase of density of the hydroxyapatite grafts and the direct bone formation in the interface region between the hydroxyapatite graft and the adjacent cancellous bone are clear radiomorphological signs for an osteointegration of hydroxyapatite grafts in the metaphyseal region.

Adult↗

A case with spondylo-metaphyseal dysplasia type A4.

We present a case with spondylo-metaphyseal dysplasia type A4 characterized by ovoid vertebral bodies with anterior tongue-like deformities, widened irregular and sclerotic metaphyseal changes, short iliac wings, slightly short long bones and short tubular bones of the hands with irregular metaphyses. She also had bipartite trochlea and irregular patellar margins, which have not been described in spondylo-metaphyseal dysplasia types to date.

Child, Preschool↗

Metaphyseal enchondrodysplasia with 2-hydroxy-glutaric aciduria: observation of a third case and further delineation.

In the course of evaluating a 17 months old boy with waddling gait and swollen joints, we found generalized, severe ossification defects in the metaphyses of his long bones. The differential diagnosis included nutritional or genetic rickets, metaphyseal dysplasia, and enchondrodysplasia. Calcium, phosphate and alkaline phosphatase were normal, while targeted analysis of urinary organic acids repeatedly revealed excretion of 2-hydroxy-glutaric acid. Thus, this child appears to have an unusual combination of findings described in just two other patients so far, a girl and a boy, and called 'spondyloenchondrodysplasia with D-2-hydroxy-glutaric aciduria'. These three cases are similar in terms of severe metaphyseal lesions, mild vertebral involvement, and presence of 2-hydroxy-glutaric acid in the urine. We consider this a radiographically and biochemically distinct entity, for which we suggest the name of 'metaphyseal enchondrodysplasia with 2-hydroxy-glutaric aciduria'.

Glutarates↗

[Lacunae between metaphyses and growth cartilage].

Metaphyseal growth defects of the distal femur are usually bilateral and well delimited. There is no pain. They are different from the cortical defects because they are closer to the metaphyseal line and more central located. They disappear with growth and there is no complication. The images are different from those of the sub-acute osteomyelitis and of metastasis. These metaphyseal growth defects are variants of the normal metaphyseal resorption.

Adolescent↗

[Metaphyseal chondrodysplasia of the McKusick type (cartilage-hair hypoplasia)].

Cartilage-Hair-Hypoplasia is a rare form of metaphyseal chondrodystrophia. Its clinical picture is characterized by dysproportionate deficient growth shift to length of upper part of the body. The hair diameter is reduced, and the eyebrows are defectly marked. After stimulation by insulin, the levels of somatotropic hormone are found in the acromegalic range. The bone structure is rarefied at the distal metaphyses of the metacarpals and the proximal metaphyses of the finger basal phalanges. The most important roentgenologic symptoms to be found are clowdy, cystic rarefactions at the distal femoral metaphyses. As to the pathophysiology, deficient proliferation of cartilaginous cells is mentioned in literature.

Cartilage Diseases↗

Metaphysics and medical ethics.

I take issue with Frank Leavitt's sketch of a pragmatic criterion for the relevance of metaphysics to medical ethics. I argue that appeal to the potential for confusion generated by metaphysical subtlety establishes a need for better communication rather than shows philosophical insight beside the point. I demonstrate that the proposed Criterion of Relevance has absurd consequences, and I claim that the relevance of philosophical doctrines, whether ethical or metaphysical, is best accounted for in terms of improved understanding.

Decision Making↗

Mind, medicine, and metaphysics: reflections on the reclamation of the human spirit.

Following the publication of such works as Auguste Comte's Cour de Philosophie Positive (1830-1842), in which he argued the inherent immaturity of metaphysical discourse, metaphysics, for Western intellectuals--and especially for Western intellectuals committed to science--has largely been abandoned. In recent years, however, we have seen renewed interest in metaphysics among some researchers and clinicians, due, in part, to increasing attempts to integrate diverse fields of study into some unified and coherent understanding of human life. For many psychologists and psychiatrists, this renewed interest is accompanied by an implicit, and sometimes explicit, re-embrace of the notion of the "human spirit." In this paper we explore some of the processes animating this movement and some of the clinical implications that flow from it.

History, 18th Century↗

[Early diagnosis, variety of outcomes and prognosis of juvenile schizophrenia with over-value disorders of the "metaphysical intoxication" type onset (results of a late follow-up study)].

On the basis of follow-up findings about juvenile schizophrenia first expressed in superworship manifestations according to the type of metaphysical intoxication (98 observations), the authors established that most frequently these cases were characterized by a torpid course of the disease in the framework of slowly progressing juvenile schizophrenia. There was a high rate of favourable outcomes at the level of "clinical recovery" (in 42.5%). Favourable prognostic signs were as follows: the complete nature of the clinical picture of the syndrome, its similarity to pubertal crisis manifestations, the absence in its structure of other positive disturbances and a number of specific features of the premorbid picture. The authors determined the pattern of correlation between the typological characteristics of the state of juvenile metaphysical intoxication and the outcome of the disease, peculiarities of manifestations of this phenomenon at the initial stage of psychotic forms of juvenile schizophrenia, as well as distinctive features of superworship formations according to the type of juvenile metaphysical intoxication observed in the framework of pubertal decompensation in schizoid psychopathies.

Adolescent↗

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↗

Metaphyseal dysplasia: a new autosomal dominant type in a large German kindred.

We describe a new autosomal dominant type of metaphyseal dysplasia (MD) in five generations of a German kindred. The main characteristics are metaphyseal widening and undermodeling of the tubular bones with Erlenmeyer flask-like appearance of the distal femora (typical of MD), with unusually severe varus deformity of the radii and flat exostoses of the long bones localized in the metaphyses. The skull is unaffected. Allelism with craniometaphyseal dysplasia (CMD) was excluded by linkage analysis.

Child↗

Hand involvement in Schmid metaphyseal chondrodysplasia.

Schmid metaphyseal chondrodysplasia (Schmid MCD, MIM 156500) is caused by mutations in the COL10A1 gene and is clinically characterized by short stature, bowed legs, and a waddling gait. Radiographic findings include anterior cupping, sclerosis and splaying of the ribs, diffuse metaphyseal flaring, and irregularity that is most pronounced at the knees, coxa vara, and femoral bowing. We reviewed the radiographs of Schmid MCD patients at the International Skeletal Dysplasia Registry in Los Angeles for evidence of hand involvement. We found hand involvement in 47% (7/15) of cases included in our analysis. These changes were subtle and consisted of shortening of the tubular bones and metaphyseal cupping of the proximal phalanges and metacarpals. Mild hand involvement is a common feature of Schmid MCD.

Collagen Type X↗

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↗

Biological effects of calcium sulfate as a bone graft substitute in ovine metaphyseal defects.

Calcium sulfate has been used as a bone graft substitute in many fields, from dentistry to orthopedics. However, the results of many studies have yielded inconclusive results. In the present study, a sheep model was used with tibial and femoral metaphyseal defects to determine whether calcium sulfate was as effective as autograft and allograft in promoting new bone formation in a critical size defect. Medical-grade calcium sulfate pellets, autograft bone, allograft bone, or nothing was used to fill the metaphyseal defects. The sheep were allowed to heal for 12 weeks. Sagittal sections from the bones were analyzed with high-resolution contact radiographs, backscattered electron microscopy, and light microscopy. The volume fractions of bone within the defect perimeter were determined, and the histologic quality of the bone was observed. The volume fraction of new bone in the autograft, calcium sulfate, and allograft were not statistically different, but all were significantly different than the untreated control. The majority of the calcium sulfate had been resorbed at 12 weeks, and the histologic quality of the bone appeared similar to the autograft-treated bone. Calcium sulfate appears to be a useful biocompatible bone graft substitute that yields results similar to autograft bone in sheep metaphyseal defects.

Animals↗

Stress analysis of a condylar knee tibial component: influence of metaphyseal shell properties and cement injection depth.

We generated three-dimensional finite element models of the proximal tibia with an implanted tibial component. The component features a cobalt-chromium tray with four short vertical posts and a porous-coated surface for improved fixation to polymethylmethacrylate (PMMA). We examined the stresses after varying: the structural rigidity of the metaphyseal cortical shell; the surface area of the cobalt-chromium tray; and the depth of pressure-injected PMMA bone cement. Our results indicate that previous finite element models of prosthetic tibial components have overestimated the structural contribution of the metaphyseal cortical shell by a factor of approximately 6. A standard size tray, in contrast to a tray that extends to the cortical shell, does not significantly alter the axial load distribution but could result in bone resorption beyond the tray periphery. An important consequence of the component peg locations is that they direct the compressive stresses into dense regions of trabeculae that run from the subchondral articular surface to the metaphyseal-diaphyseal junction. The use of a modified von Mises failure criterion suggests that at excessive load levels the most likely location of material failure is at the bone cement-trabecular bone interface immediately distal to the fixation posts. Due to its added rigidity, injection of cement beyond the fixation posts results in slightly increased stresses in this region, but these stress increases are compensated for by an increased strength of the cement-bone composite.

Bone Cements↗

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↗

Studies on extractable and resistant proteoglycans from metaphyseal and cortical bone and cartilage.

Soluble proteoglycans (SPG) were extracted from bovine (BCC) and human (HCC) costal cartilages by the dissociative method using 4 M guanidinium chloride (GuHCl). Proteoglycans which are resistant to extraction (RPG) were obtained following collagenase digestion or hydroxylamine treatment of the cartilage residues. Similarly, SPG were extracted from bovine metaphyseal and cortical bone using EDTA. The RPG were extracted from the bones using hydroxylamine. Density gradient fractionation under dissociative conditions of cartilage SPG and RPG followed by chromatography on Sepharose 2B revealed that A1D1 RPG are smaller than the SPG. SPG reacted with either collagenase or hydroxylamine are also smaller than the parent SPG. A1D1 fractions obtained from BCC-SPG and RPG or from mixtures of SPG and acid-soluble collagen are free of hydroxyproline. Hydroxyproline is not completely separated from HCC-RPG. Density gradient fractionation of bone proteoglycans and Sepharose chromatography of the A1 and A1D1 fractions showed that those obtained from metaphysis are larger than those from cortical bone. This was attributed to the presence of calcified cartilage in metaphyseal bone. The A1D1 fractions of the metaphyseal proteoglycans seemed to undergo self-association since this fraction is larger than the A1 fraction from which it is derived. Cortical bone proteoglycans do not behave similarly. Density gradient purification under dissociative conditions failed to separate hydroxyproline from the proteoglycans obtained from bone. It is hypothesized that in bone proteoglycans and collagen might be linked.

Animals↗