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At least 19 recordsLinked to original sources

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

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

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

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

"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

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

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

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

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

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

The use of the powered metaphyseal stapler for reconstructive procedures in the adult foot.

We have evaluated the Powered Metaphyseal Stapler in various procedures in the adult foot to determine the effectiveness of this form of internal fixation. Thirty-five patients had 40 operations (five bilateral). In all but one case there was both clinical and radiographic evidence of a solid bony union. Backing out of the staples has been a minor problem that has required staple removal in three patients. The Powered Metaphyseal Stapler appears to offer a most satisfactory option for internal fixation in the foot, when used in metaphyseal or cancellous bone, as either primary or adjuvant fixation.

Adult

Metaphyseal multifocal osteosarcoma.

Two patients, aged six and eight years, having metaphyseal osteolytic and osteoblastic multifocal osteosarcoma are described. The condition is named "metaphyseal multifocal osteosarcoma". The metaphyseal areas are the sites of the pathological process. It can be postulated that a certain intensity of growth activity is the predominant factor in this condition and that this accounts for its multicentered presentation.

Arm

Hematogenous osteomyelitis of metaphyseal-equivalent locations.

Flat and irregular bones have anatomic subdivisions comparable to long bones. This concept is useful in the radiograpic evaluation of solitary bone lesions. Areas adjacent to cartilage are metaphyseal-equivalent locations. Prior to skeletal maturation, metaphyseal-type vascular anatomy predisposes these sites to involvement by hematogenous osteomyelitis. Approximately 30% of cases of hematogenous osteomyelitis affect these metaphyseal-equivalent sites and often present difficult diagnostic challenges. Forty-nine patients with this condition are described.

Adolescent

Oblique metaphyseal osteotomy for the correction of Tailor's bunions: a 3-year review.

This study presents a 3-year review of patients undergoing a fifth metaphyseal osteotomy for the treatment of Tailor's bunions. Postoperative analysis consisted of patient's subjective appraisal, activity level, physical examination, and radiographic studies. The fifth metaphyseal osteotomy, in this study, reduced lateral deviation and fourth-fifth intermetatarsal angles to less than or equal to normal values, while decreasing intermetatarsal head distance and returning the fifth metatarsophalangeal joint to congruency. Patient satisfaction was high while providing a low incidence of transfer lesions. This manuscript demonstrates the fifth metaphyseal osteotomy to be a viable treatment for Tailor's bunions.

Adolescent

Fibrous metaphyseal defect.

The tendon and ligaments inserted into the perichondrium of the epiphyseal plate were examined in 152 autopsy specimens of tubular long bones. In the region of two areas where tendons were inserted (Ranvier's nodes), the normal medullary tissue is replaced by fibroblastic tissue. A retrospective radiological examination of 155 fibrous metaphyseal defects shows that they are situated at characteristic sites on the circumference of the metaphysis of long tubular bones. This can be related to the insertion of a tendon or ligament near the epiphyseal growth plate which corresponds to areas found in the morphological study and is the site of origin of fibrous metaphyseal defects.

Bone Diseases, Developmental

Metaphyseal sclerosis in patients with chronic renal failure.

We reviewed radiographs of the hands and wrists of 33 patients with immature skeletons and chronic renal disease. Various radiographic manifestations of renal osteodystrophy were seen, including osteopenia in 23 patients (70%), subperiosteal resorption in 20 (61%), distal tuft resorption in 14 (42%), sclerosis of vertebral bodies in 2 (6%), and soft-tissue calcification in 1 (3%). We also noted that 13 patients (39%) exhibited metaphyseal sclerosis adjacent to the growth plates. Five of these 13 showed persistent sclerosis years after the growth plates had fused. None of the patients showed other radiographic changes of rickets, and there was no correlation between the serum calcium, phosphorus, or aluminum levels and the presence of metaphyseal sclerosis. Neither was there any association with the underlying cause of renal failure, method of treatment, presence of a transplant, or type of dialysis. We view this finding as another manifestation of renal osteodystrophy. The importance of distinguishing it from other sclerotic lesions is discussed.

Adolescent