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PubMedDate not supplied

A newly recognized pattern of canine osteochondromatosis.

Clinicopathological findings are described for a unique skeletal pattern of osteochondromatosis (syn. multiple osteochondromas) in three crossbred littermate dogs. Multiple nonpainful bilaterally symmetric skeletal lesions arose from focal semiannular and annular areas of periosteal thickening on the cortical surface of the metaphyses and diaphyses of long bones. Flat bones of the skull were spared. In radiographs osteochondromas in different stages of evolution were apparent. Grossly there were smoothly contoured, nodular subperiosteal masses of dense fibrocartilaginous and osseous tissue that were continuous with and overlying apparently normal but thin trabeculae of cancellous bone. Cortical compacta was attenuated or absent beneath exostoses. In histologic sections of the cartilage-capped exostoses a hyperplastic periosteum formed a focal semiannular or annular cap of proliferative hyaline cartilage tissue that underwent endochondral ossification and replacement by cancellous bone at its base. Intertrabecular spaces in the cancellous bone of exostoses were filled with fibro-osseous and hematopoietic tissue. A hereditary origin was suspected for the osteochondromas. Origin of some osteochondromas as semiannular or annular perturbations of the perichondrial ring of metaphyseal physes of long bones likely contributed to limb shortening and a pattern of billaterally symmetric angular limb deformities of all limbs as occurs in some children affected by osteochondromatosis.

Animals↗
PubMed2003

The ignis fatuus of reduction and unification: back to the rough ground.

Given the enormous variety of possible intertheoretical relations, the proliferation of definitions of reduction, supervenience, emergence, unification, and so on, as well as the fact that empirical studies have provided support for almost any metaphysical option or, alternatively, have shown rather conclusively that empirically the case is inconclusive, I suggest a moratorium on the use of words such as "reduction," "supervenience," and "unification" and to go back to the rough ground and give perspicuous renderings of the practice of chemistry. What is needed are very detailed case studies and further discussions about them, instead of bickering about whether chemistry can be reduced to physics, supervenes on it, can be unified with it, and similar "metaphysical" concerns.

Journal Article↗
PubMed1998

Measurement of mechanical characteristics of tibial periosteum and evaluation of local differences.

Stress-strain relationships of bovine tibial periosteum, harvested from anterior, medial, lateral, and posterior aspects of tibia, were successfully measured using a newly developed experimental system. Results showed a curvilinear stress-strain pattern having three regions, i.e., toe, almost linear, and rupture regions, which resembled those of biological soft tissues like ligaments, skin, etc. Tensile moduli in the toe region (Ee) and in the linear region (Ec) were obtained by linear regressional analyses. These values and the tensile strength (sigma t) showed clear local differences. The values of Ee, Ec, and sigma t in the longitudinal direction in the metaphyseal regions where ligaments or connective tissues attach were approximately two times larger than those in the diaphysis, where muscles or connective tissues attach. However, these properties in the metaphyseal and diaphyseal regions with muscle attachments were almost the same. In the transverse direction, these properties in the anterior proximal metaphysis were approximately two times larger than those in the diaphysis and in the distal metaphysis. In the other regions, these properties appeared not to be significantly different. These results clearly demonstrate that the mechanical properties of periosteum are strongly influenced by the ligament and muscle attachments.

Animals↗
PubMed1995

Physical activity, calcium intake, and bone mineral content in children in The Netherlands.

STUDY OBJECTIVE: To examine the relation between physical activity, calcium intake, and bone mineral content in children. DESIGN: Population based, cross sectional study. SETTING: Primary schools in Zoetermeer, The Netherlands. PARTICIPANTS: Altogether 1359 Dutch boys and girls, aged 7 to 11 years (response rate 88%). MEASUREMENTS: Bone mineral content was measured by quantitative roentgen microdensitometry of the midphalanx of the second digit at the diaphyseal and metaphyseal site. Maximal exercise testing, according to the Bruce treadmill protocol, was used to assess physical fitness. Habitual physical activity was assessed by use of a questionnaire on physical activities. Daily calcium intake from dairy products was estimated by use of a semiquantitative food frequency questionnaire. MAIN RESULTS: Bone mineral content in boys was not linearly associated with physical fitness after adjustments for differences in height, body weight, chronological age, and skeletal age. In girls a linear association was found at the metaphyseal site only. When extreme groups were compared, bone mineral content was found to be higher in "high fitness children" (upper decile) than "low fitness children" (lowest decile), with statistical significance reached in boys only. When analyses were performed in subgroups of skeletal age, a clear linear relation between physical fitness and bone mineral content was seen in the mature subgroup in both boys and girls. No linear association was found between habitual physical activity and bone mineral content, while the results in extreme groups (that is, upper versus lowest decile) and in subgroups of skeletal age were comparable to those on physical fitness in boys only. No association was found between daily calcium intake and bone mineral content in this age group. CONCLUSIONS: This cross sectional study in children aged 7 to 11 years suggests that an increased bone mineral content is found only in those with a high level of physical activity. This association is most pronounced in the more mature children. No evidence was found for an association between daily calcium intake and bone mineral content in childhood.

Age Determination by Skeleton↗
PubMed1990

Two philosophers in search of a contradiction: a response to Singer and Kuhse.

Peter Singer and Helga Kuhse reject my claim that because their views on the mortality of infanticide are metaphysically incommensurate with those of Paul Ramsey they cannot refute his position. According to them, I have failed to see that Ramsey contradicts himself. Once this is seen, no further refutation is needed. I argue that there is no contradiction and offer further thoughts on the metaphysically incommensurate.

Ethical Analysis↗
PubMed2000

The morality of abortion and the deprivation of futures.

In an influential essay entitled Why abortion is wrong, Donald Marquis argues that killing actual persons is wrong because it unjustly deprives victims of their future; that the fetus has a future similar in morally relevant respects to the future lost by competent adult homicide victims, and that, as consequence, abortion is justifiable only in the same circumstances in which killing competent adult human beings is justifiable. The metaphysical claim implicit in the first premise, that actual persons have a future of value, is ambiguous. The Future Like Ours argument (FLO) would be valid if "future of value" were used consistently to mean either "potential future of value" or "self-represented future of value", and FLO would be sound if one or the other interpretation supported both the moral claim and the metaphysical claim, but if, as I argue, any interpretation which makes the argument valid renders it unsound, then FLO must be rejected. Its apparent strength derives from equivocation on the concept of "a future of value".

Aborted Fetus↗
PubMed1990

The clinical features of osteogenesis imperfecta resulting from a non-functional carboxy terminal pro alpha 1(I) propeptide of type I procollagen and a severe deficiency of normal type I collagen in tissues.

The features of a baby with lethal perinatal osteogenesis imperfecta (OI II), owing to a frameshift mutation that resulted in the production of a truncated and functionless carboxy terminal propeptide of the pro alpha 1(I) chain of type I procollagen, were studied. The baby (OI26) was heterozygous for an insertion of a single uridine nucleotide after base pair 4088 of the prepro alpha 1(I) mRNA of type I procollagen. Only normal type I collagen was incorporated into the extracellular matrix of bone and dermis resulting in a type I collagen content of about 20% of control tissues. The baby was born at 35 weeks' gestation and died shortly afterwards. He was small and had the radiographical features most like those of OI IIB. The skeleton was poorly ossified. The ribs were discontinuously beaded and the femora were broad with multiple healed fractures of the diaphyses and metaphyses. Other long bones had broad metaphyses with overmodelled diaphyses. The calvarium contained many hundreds of wormian bones. Histological examination showed grossly deficient endochondral and intramembranous ossification. The bone was of a woven type without evidence of lamellar bone or Haversian systems and the osteoblasts did not mature into osteocytes. The cortex of the femur contained Haversian canals but they were surrounded by loose collagen fibres and a mosaic pattern of woven bone and islands of cartilage. We propose that OI IIB can be sub-classified into two groups, one with helical mutations and both normal and mutant type I collagen in the tissues, and the other with carboxy terminal propeptide mutations and a severe type I collagen deficiency, but without mutant collagen in the tissues.

Bone and Bones↗
PubMed1991

Short stature/short limb skeletal dysplasia with severe combined immunodeficiency and bowing of the femora: report of two patients and review.

We report two patients with severe combined immunodeficiency and short stature/short limb skeletal dysplasia. Case 1 presented at birth with rhizomelic shortening of the extremities and bowing of the femora. She developed clinical signs of severe combined immunodeficiency at 13 months and died at 21 months. Case 2 had severe prenatal shortening and bowing of the extremities and a small, malformed chest. Symptoms of severe combined immunodeficiency and severe failure to thrive developed soon after birth and she died at 5 months. The diagnosis of severe combined immunodeficiency in our patients was based on their clinical course and necropsy findings, supported in case 1 by the results of immune function tests. The results of investigation of immune function (immunoglobulins, lymphocyte subpopulations, lymphocyte function) are very variable in this syndrome as in other variants of severe combined immunodeficiency. Bone histopathology in both patients showed grossly irregular costochondral junctions, but normal transition of proliferating to hypertrophic chondrocytes. These cases belong to early lethal type 1 short limb skeletal dysplasia with severe combined immunodeficiency. Review of previously published cases with severe combined immunodeficiency and well documented skeletal findings show eight patients with prenatal onset of bowing and shortening of the extremities and metaphyseal abnormalities. These include two sib pairs concordant for the skeletal changes. In these cases, adenosine deaminase levels were not reported. An additional four published cases with associated adenosine deaminase deficiency had only mild metaphyseal abnormalities, but subsequently showed no linear growth.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Deaminase↗
PubMed1996

Arachnoid cyst and chronic subdural haematoma in a child with osteogenesis imperfecta type III resulting from the substitution of glycine 1006 by alanine in the pro alpha 2(I) chain of type I procollagen.

The features of a child with osteogenesis imperfecta type III (OI III) resulting from the heterozygous substitution of glycine 1006 by alanine in the pro alpha 2(I) chain of type I procollagen were studied. He was born at term with the clinical features of severe OI, including deep grey-blue sclerae. He had severe osteopenia and all long bones were smaller than normal with cortical thinning, metaphyseal expansion, poor metaphyseal modelling, and multiple fractures. However, the vertebrae, pelvis, and shoulder girdle were of normal shape and there were few rib fractures. Histological examination of the calvarium and tibial shaft showed woven bone without lamellar bone or Haversian systems. The shafts of the long bones were widened owing to repeated fractures. Progressive enlargement of the calvarium occurred between 3 and 4.5 months of age owing to bilateral chronic subdural haematomata and a large arachnoid cyst in the Sylvian fissure. The cyst was probably developmental in origin while the subdural collections were probably the result of perinatal skull trauma. The cyst and the subdural collections resolved following drainage but ventricular dilatation with normal cerebrospinal fluid pressure followed. The proband is the first reported case of OI with a glycine substitution by alanine in the pro alpha 2(I) chain of type I procollagen.

Adult↗
PubMed1987

Haematogenous osteomyelitis in cattle.

The examination of 70 cattle with haematogenous osteomyelitis resulted in the classification of the bone lesions into two main groups: the physeal type, in which an infection, usually of metaphyseal bone, originated at or near the growth plate, usually in the distal metacarpus, metatarsus, radius or tibia, and the epiphyseal type, in which an infection originated near the junction of the subchondral bone and the immature epiphyseal joint cartilage, most often in the distal femoral condyle epiphysis, the patella and the distal radius. Combinations of physeal and epiphyseal defects and even diaphyseal involvement were occasionally seen. Epiphyseal osteomyelitis was mostly caused by salmonella infection, physeal by Corynebacterium pyogenes, salmonella and other bacteria. The salmonella affected animals were with one exception less than 12 weeks old and the majority had had some previous illness or came from a problem herd. The C pyogenes affected calves were in almost all cases more than six months old. The prognosis of the metaphyseal infection was in general satisfactory, and surgical intervention (osteotomy or sequestrectomy) was often required. The prognosis of the epiphyseal type was grave but two of the three animals in which physeal and epiphyseal defects were accompanied by diaphyseal lesions recovered.

Animals↗
PubMedDate not supplied

Skeletal complications in pediatric oncology patients.

Pediatric oncology patients are at risk for the development of numerous skeletal complications, and radiologic studies are important in the identification and evaluation of these conditions. Methotrexate osteopathy manifests as osteopenia, dense provisional zones of calcification, pathologic fractures, and sharply outlined epiphyses. Hypertrophic osteoarthropathy may occur with nasopharyngeal carcinoma or tumors of the lungs or pleura and manifests as cortical thickening, lamellar periosteal new bone formation, and soft-tissue swelling. Biomechanical abnormalities are often seen at bone scintigraphy in patients who have undergone surgery for bone tumors. Growth plate injury may manifest as marked deformity, sclerotic metaphyseal bands, metaphyseal fraying, and longitudinal striations. Radiation "osteitis" is seen as an initial decrease in bone density with subsequent development of a mixed radiolucent and sclerotic appearance. Ischemic necrosis of the femoral heads is best demonstrated at magnetic resonance (MR) imaging and has low signal intensity on T1-weighted images and a high-signal-intensity rim on T2-weighted images. Bone infarcts are seen as well-demarcated, often ring-shaped areas of decreased signal intensity on T1-weighted MR images and as areas of increased signal intensity on short-inversion-time inversion recovery images. Radiographic signs of infection include bone destruction, periosteal new bone formation, and sclerotic changes. Short-inversion-time inversion recovery MR imaging is particularly useful in evaluating posttherapy changes in bone marrow. Osteochondroma may demonstrate a cartilaginous cap at MR imaging, whereas the most important finding in radiation-induced sarcoma is a soft-tissue mass. Radiologists who work with children with cancer need to be familiar with these complications and their imaging appearances.

Antineoplastic Agents↗
PubMed2004

Skeletal development in fetal pig specimens: MR imaging of femur with histologic comparison.

PURPOSE: To evaluate the magnetic resonance (MR) imaging features of the developing femur in fetal pig specimens. MATERIALS AND METHODS: MR images of 15 fetal pig femurs, which were categorized into three groups of specimens representing each third of the gestational period, were used to compare increasing femoral length (as an indication of gestational age) with epiphyseal growth in multiple dimensions by using Pearson product moment correlation. Physeal-epiphyseal demarcation, visibility of the secondary ossification center and its physis, prominence of the perichondrial structures (ie, groove of Ranvier and bone bark), metaphyseal undulation, and corticomedullary differences were evaluated qualitatively. These features were also evaluated on histologic sections. RESULTS: With femoral length measurements used as indications of gestational age, there were three, five, and seven fetal pig specimens in each gestation group. During fetal development, the cartilaginous epiphysis of the distal femur transformed from an oval to a bicondylar structure, with most of the growth occurring sagittally (P < .001). Physeal-epiphyseal demarcation, visibility of the secondary ossification center and its physis, and metaphyseal undulation increased later in gestation. Detection of perichondrial structures, however, was greatest during the middle third of gestation and decreased thereafter. During the fetal period, the perichondrial groove of Ranvier and the bone bark were easily identifiable at MR imaging. Marrow cavitation increased with gestation. CONCLUSION: MR imaging depicts fetal pig skeletal features that can be confirmed histologically and that may prove to be useful at human prenatal skeletal imaging.

Animals↗
PubMed1991

MR imaging of diffuse bone marrow replacement in pediatric patients with cancer.

In the magnetic resonance (MR) imaging examinations of three children with tumors (two neuroblastoma, one rhabdomyosarcoma) and three with leukemia, the marrow demonstrated a diffuse, uniform pattern of hypointensity on T1-weighted images and hyperintensity on T2-weighted images. The authors observed that this reversal ("flip-flop") of the usual MR characteristics of fatty marrow was seen in the epiphyses, metaphyses, and diaphyses. The purpose of this study was to establish the radiographic and clinicopathologic correlates of this MR finding on the basis of findings from plain radiographs, bone scans, and bone marrow aspirates. Plain radiographs and bone scans demonstrated either normal findings or changes limited to the metaphyses. In all patients, analysis of bone marrow aspirates demonstrated metastases. The authors concluded that even in the absence of evidence of discrete bone metastases on a plain radiograph or a bone scan, this diffuse and uniform "flip-flop" pattern reflects diffuse marrow replacement by tumor cells.

Bone Marrow↗
PubMed1992

Are long bone radiographs necessary in neonates suspected of having congenital syphilis?

The frequency of appendicular bone abnormalities was prospectively evaluated in 93 newborns suspected of having congenital syphilis. The evaluation of each newborn included prenatal history, physical examination, serologic tests, and long bone radiography, which was performed during the first week after birth. In all patients, results of at least one serologic test for syphilis were positive or proof of syphilis was found at autopsy. In 75 patients (81%), the long bone radiographs were normal. The nonspecific finding of lucent metaphyseal bands was the most common abnormality on long bone radiographs; only five newborns had more specific changes of syphilis in the metaphyses and periosteal reaction. In view of the low frequency of relatively specific radiographic findings in the long bones, the authors recommend that long bone radiography not be a part of the routine evaluation of full-term newborns suspected of having congenital syphilis.

Bone Diseases↗
PubMed1995

Soft-tissue sarcomas: MR imaging findings after treatment in three pediatric patients.

PURPOSE: To characterize the skeletal and bone marrow magnetic resonance (MR) imaging changes during and after treatment of childhood soft-tissue tumors. MATERIALS AND METHODS: Three boys with soft-tissue sarcomas of the popliteal fossa underwent surgery, radiation therapy, and chemotherapy. Plain radiographic and MR imaging findings were correlated with the effect of treatment. RESULTS: After radiation therapy, MR images revealed findings that resembled those of rickets at sites of irradiation in the three patients. These findings included metaphyseal sclerosis, metaphyseal fraying, and epiphyseal plate widening. Bone marrow imaging changes were temporally related to therapy. During chemotherapy, reconversion to hematopoietic marrow was noted in nonirradiated areas in two patients, but after cessation of all treatment, these areas converted back to fatty marrow. Irradiated areas of bone marrow remained fatty throughout therapy in the three patients. CONCLUSION: Awareness of the MR imaging findings related to antineoplastic treatment of soft-tissue tumors is important to distinguish these changes from progression of primary disease.

Adolescent↗
PubMed1995

Chronically stressed wrists in adolescent gymnasts: MR imaging appearance.

PURPOSE: To investigate the magnetic resonance (MR) imaging appearance of a chronically stressed wrist and to assess the utility of MR imaging for evaluation of injuries to the growth plate. MATERIALS AND METHODS: Coronal T1-weighted spin-echo and gradient-echo MR images were obtained of 93 wrists in 47 high-risk gymnasts of a Chinese opera school. MR imaging and radiographic findings were correlated in 93 wrists. RESULTS: The major MR imaging abnormalities of 47 radii with abnormal radiographic findings were horizontal fractures (n = 23), physeal cartilage extension to metaphysis (n = 17), and physeal widening (n = 17). The major MR abnormalities of 46 radii with normal radiographs included physeal cartilage extension (n = 12), metaphyseal bone bruise (n = 8), and vertical fractures (n = 4). CONCLUSION: Physeal cartilage extension into the metaphysis represents a healing sign in chronically stressed adolescent wrists. MR imaging findings including horizontal fracture and physeal cartilage extension to the metaphysis suggest that physeal widening occurred secondary to metaphyseal injury.

Adolescent↗
PubMedDate not supplied

From the archives of the AFIP. Child abuse: radiologic-pathologic correlation.

In the United States, roughly one of every 100 children is subjected to some form of neglect or abuse; inflicted injury is responsible for approximately 1,200 deaths per year. Child physical abuse may manifest as virtually any injury pattern known to medicine. Some of the injuries observed in battered children are relatively unique to this population (especially when observed in infants) and therefore are highly suggestive of nonaccidental, or inflicted, injury. Worrisome injuries include rib fracture, metaphyseal fracture, interhemispheric extraaxial hemorrhage, shear-type brain injury, vertebral compression fracture, and small bowel hematoma and laceration. As noted, however, virtually any injury may be inflicted; therefore, careful consideration of the nature of the injury, the developmental capabilities of the child, and the given history are crucial to determine the likelihood that an injury was inflicted. The majority of these injuries are readily detectable at imaging, and radiologic examination forms the mainstay of evaluation of child physical abuse. Detection of metaphyseal fracture (regarded as the most specific radiographically detectable injury in abuse) depends on high-quality, small field-of-view radiographs. The injury manifests radiographically as a lucent area within the subphyseal metaphysis, extending completely or partially across the metaphysis, roughly perpendicular to the long axis of the bone. Acute rib fractures (which in infants are strongly correlated with abuse) appear as linear lucent areas. They may be difficult to discern when acute; thus, follow-up radiography increases detection of these fractures. For skull injuries, radiography is best for detecting fractures, but computed tomography and magnetic resonance imaging best depict intracranial injury.

Archives↗
PubMed1983

Effects of spaceflight on trabecular bone in rats.

Alterations in trabecular bone were observed in growing male Wistar rats after 18.5 days of orbital flight on the COSMOS 1129 biosatellite. Spaceflight induced a decreased mass of mineralized tissue and an increased fat content of the bone marrow in the proximal tibial and humeral metaphyses. The osteoblast population appeared to decline immediately adjacent to the growth cartilage-metaphyseal junction, but osteoclast numbers were unchanged. These results suggested that bone formation may have been inhibited during spaceflight, but resorption remained constant. With the exception of trabecular bone mass in the proximal tibia, the observed skeletal changes returned to normal during a 29-day postflight period.

Animals↗