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I Hershkovitz

Publications and source records attributed to I Hershkovitz.

At least 19 recordsLinked to original sources
PubMed2001

Three-dimensional finite element analysis of the facial skeleton on simulated occlusal loading.

Development of predictive models of occlusal loading of the facial skeleton will be of value for prosthetic design in oral rehabilitation. A 3-D finite element (FE) model of a human skull, based on CT scans, was constructed to analyse strain and stress distribution in the facial skeleton caused by simulated occlusal loading. Vertical loads were applied simulating loading of the full maxillary arch and unilateral single point occlusal loading of maxillary molar, pre-molar, canine and incisor sites. Strain and stress regimes from Von Mises (VM) failure criteria and extension and compression diagrams showed even distribution of strain following loading of the full maxillary arch throughout the facial elements. For individual points, the highest VM concentrations were consistently located on the facial aspect several mm above the loading site. Strain trajectories divided into a 'V-shaped' pattern, from the loading point into medial and lateral branches with higher VM values in the medial. As the same load was applied from the posterior to anterior region, VM values increased on all facial areas. Strain patterns were less symmetric and there was an increase in strain in the alveolar arch and around the rim of the nasal cavity. The overall picture of the facial skeleton is of a vertical plate enabling it to withstand occlusal stresses by in-plane loading and bending in its own plane. The most efficient distribution of load was on maxillary full arch loading with the most unfavourable strain concentrations occurring on loading in the anterior region.

Adult↗
PubMed1999

Metastatic cancer in the Jurassic.

Recognition of cancer in extreme antiquity has been limited to osteomas in mosasaurs and haemangiomas and growths of unclear origin in dinosaurs. We describe a metastatic cancer in a dinosaur.

Animal Diseases↗
PubMed1999

The elusive diploic veins: anthropological and anatomical perspective.

Diploic veins (Canales diploicae), which were identified in dogs by Dupuytren more than 200 years ago (Hecker [1845] Die anatomische Verhaltnisse und Krankheiten der Venae diploicae und Vasa emissaria. Erfahrungen und Abhandlungen im Gebiete der Chirurgie und Augenheilkunde. Erlangen), have remained inadequately understood and scantily referenced in the anatomical and anthropological literature. The tunnels formed by diploic veins are among the few known skeletal markers of soft tissue alteration. Protected by two bony laminae, diploic vein tunnels often resist postdepositional destruction and may provide a new way to assess living and extinct hominid populations. This basic research was carried out to enable future utilization of the diploic venous channels in anthropologic research. In the present study, diploic venous channels were observed radiographically in 108 human adults aged 19 years and above, 18 infants and children aged 1-18 years (Hamann-Todd Osteological Collection), eight fetuses aged 7-9 months (the Johns Hopkins Collection), and seven nonhuman primates (Hamann-Todd Osteological Collection). In addition, seven documented cases of parents and children were radiographed for genetic evaluation (Osteological Collection of The Hungarian Natural History Museum). Five distinct diploic distribution patterns were identified and described in this study. This was at variance with the impressions reported in dissection-based studies. Independence of diploic vein pattern from demographic (gender and age) and size factors and their tendency to be symmetrical make them amenable and reliable traits for skeletal population study. Diploic vein patterns appeared to be more complicated in humans than in nonhuman primates, raising the possibility of future phylogenetic applications.

Adolescent↗
PubMed1999

Hyperostosis frontalis interna: an anthropological perspective.

Hyperostosis frontalis interna (HFI) is manifested by the accretion of bone on the inner table of the frontal bone. Despite the vast literature on HFI, ambiguity exists as to its etiology, osteogenesis, demography, and history. This stimulated the present broad-scale study of HFI which included the evaluation of 1,706 early 20th century skulls (1,007 males and 699 females) from the Hamann-Todd and Terry human osteological collections, as well as 2,019 pre-19th century East-Mediterranean, Amerindian, and Central European skulls. In addition, 72 cadavers were dissected for gross inspection and histology. Special attention was paid to the relationship of the brain and meninges to endocranial lesions. HFI is an independent condition, not a symptom of a more generalized syndrome as suggested in the past. It can appear in a variety of forms but each is the result of the same process and probably of the same etiology. Investigators' previous failure to recognize the mild stages of HFI (types A and B) as an early form of the general HFI process led to erroneous statistics and interpretations of observations. HFI should also be considered a phenomenon separate from HCI, hyperostosis cranialis diffusa (HCD), and other endostoses, even when it appears in association with them. To avoid ambiguity and facilitate the description of cranial hyperostoses, uniform nomenclature (HFI, HCD) has been recommended. HFI is rarely seen in historic populations, regardless of geographical origin. It is most commonly found among females and is believed to be associated with prolonged estrogen stimulation. While its magnitude of manifestation and frequency are much higher in females, HFI is not a purely female phenomenon. Males with hormonal disturbances such as atrophic testis were found to manifest HFI type D. HFI is associated with age insofar as it is much less frequent in females under 40 years of age. Although advanced cases of HFI (types C and D) have been observed in individuals as young as 40 years of age, it is more frequently found after age 60. The frequency of HFI type D will not increase from age 60. Type-predicted analysis by cohort reveals significant ethnic differences. Changes in African American (AA) females appear earlier in life and progress more rapidly than in European American (EA) females. Analysis of radiographs shows a discrepancy between the anatomic prevalence of HFI and its radiological recognition, which is very poor for mild cases. This apparently resulted in the misconceptions that HFI is entirely an old-age phenomenon, and that it is exclusively female. Histological analysis shows that the inner table along with the closely attached dural layer play a major role in the osteogenesis of HFI. Contrary to previous models, no evidence for diploe or ectocranial plate involvement was found. Cadaver study suggests that the predilection for the frontal area may be related to an altered blood supply and/or vascular stretching.

Adult↗
PubMed1999

First rib metamorphosis: its possible utility for human age-at-death estimation.

Human first ribs demonstrate predictable, sequential changes in shape, size, and texture with increasing age, and thus, can be used as an indicator of age at death. Metamorphosis of the first rib's head, tubercle, and costal face was documented in a cross-sectional sample of preadult and adult first ribs of known age at death from the Hamann-Todd skeletal collection (Cleveland Museum of Natural History, Cleveland, Ohio). Blind tests of the usefulness of the first rib as an age indicator were conducted, including tabulation of intraobserver and interobserver inaccuracies and biases. First rib age estimates show inaccuracies and biases by decade comparable to those generated by other aging techniques. Indeed, the first rib method is useful as an isolated age indicator. When used in conjunction with other age indicators, the first rib improves the quality of summary age assessments.

Adolescent↗
PubMed1998

Clues potentially distinguishing lytic lesions of multiple myeloma from those of metastatic carcinoma.

This study was conducted to determine whether individual bony lesions are specific for recognizing multiple myeloma and thereby distinguish it from metastatic cancer and leukemia. The lytic skeletal lesions of multiple myeloma are characterized by sharply defined, spheroid lesions. They have smooth borders and effaced/erased trabeculae. Unique spheroid myeloma lesions appear to be responsible for the "punched out" appearance of affected bone. The total absence of remodeling in myeloma forms a contrast to irregular preservation of trabeculae and buttressing, isolated "fronts of" cortical bone "resorption" coalescing to confluence, and the "golf-ball surface" phenomenon observed in metastatic cancer. The uniform effacement of both cortical and trabecular bone in multiple myeloma also contrasts with some cortical preservation in metastatic cancer. Leukemic lesions are more numerous than those of myeloma, but they lack the latter's "space-occupied" appearance. The relatively small holes and "fronts of resorption" of leukemia are quite different from the "space-occupied" lesions of multiple myeloma. Uniform size is a characteristic traditionally attributed to the bone lesions of multiple myeloma. The occurrence of isolated examples of uniform size lesions in metastatic cancer and of variable size lesions in some individuals with multiple myeloma precludes unequivocal use of size in differential diagnosis. Fortunately, the newly recognized macroscopic characteristics appear to separate multiple myeloma from metastatic cancer, and also distinguish myeloma from leukemia.

Diagnosis, Differential↗
PubMed1998

Clues to recognition of fungal origin of lytic skeletal lesions.

The present study addresses the specificity of lytic osseous impact for distinguishing among metastatic cancer, tuberculosis, and fungal disease. Osseous impact is used in this manuscript as a convention to describe the macroscopic appearance of defleshed bones affected by the disease. Osseous changes in the skeleton of a 47-year-old black male, diagnosed in life as having blastomycosis, were characterized and compared to lytic lesions observed in ten individuals with tuberculosis and six with metastatic cancer in the Terry and Hamman-Todd Collections. Apparent distinguishing characteristics are identified. Eroded areas, present as fronts of resorption or the result of space-occupying masses in blastomycosis, with protruding, short, blunt, 1 x 2 mm spicules of new bone, are surrounded by periosteal reaction. These differed from smooth zones of resorption and coalesced lesions, with a smoothed marginal zone and space-occupied appearance--bone-displacing mass--in tuberculosis and lytic (nonpermeative) lesions of metastatic cancer. Displacing is a convention (an artificial term) denoting bone resorption and reformation at the outer edge of the tumor mass, giving the impression that the surrounding bone had expanded beyond its original margins. Irregular trabeculae are occasionally preserved in the margins, but remodeling in the form of blunting of those trabeculae is not observed macroscopically in either tuberculosis or metastatic cancer. Two apparently specific lesion types are noted in blastomycosis. Periosteal reaction surrounding fronts of resorption appears specific, at least for nonarticular osseous lytic lesions, among the three entities studied. Remodeling of isolated internal trabeculae in the space-occupying mass lesions of blastomycosis also appears unique among the three disorders studied. Comparison with coccidioidomycosis suggests that extrapolation of blastomycosis findings to other fungal diseases is feasible; description of additional clinically diagnosed cases is awaited.

Anthropology, Physical↗
PubMed1997

Identification of childhood arthritis in archaeological material: juvenile rheumatoid arthritis versus juvenile spondyloarthropathy.

The opportunity to examine the defleshed skeleton of an individual diagnosed in life (Hamann-Todd collection, individual 2036) afforded a unique opportunity to demonstrate the bone damage characteristic of at least one form of juvenile rheumatoid arthritis (JRA). Characteristics helpful for recognition of JRA in archaeological material include peripheral articular marginal and subchondral erosions, axial (e.g., zygapophyseal or sacroiliac) joint erosions, fusion of axial (cervical zygapophyseal) and/or peripheral joints, premature epiphyseal closure and/or ballooned epiphyses, growth retardation with underdeveloped (short and overtubulated) long bones, short mandibular rami with underdeveloped condyles and concomitant micrognathia, and demineralization (osteopenia). Distinguishing between JRA and juvenile spondyloarthropathy, however, is not always possible, as illustrated by this case.

Anthropology, Physical↗
PubMed1997

Recognition of leukemia in skeletal remains: report and comparison of two cases.

Recognition of disease in the archeologic record is facilitated by characterization of the skeletal impact of documented (in life) disease. The present study describes the osteological manifestations of leukemia as identified in the skeletons of two individuals diagnosed during life: a 3-year-old black girl with acute lymphocytic leukemia and a 60-year-old white male with acute myelogenous leukemia in the Hamann-Todd collection. Contrasting with the lack of specificity of radiologic findings, macroscopic skeletal changes appear sufficiently specific to allow distinguishing leukemia from other forms of cancer. While leukemia appears confidently diagnosable, distinguishing among the varieties (e.g., myelogenous and lymphocytic) does not appear possible at this time. Skeletal findings in leukemia are presented in tabular form to facilitate their application to future diagnosis of the disease in the archaeological record.

Archaeology↗
PubMed1997

The elusive petroexoccipital articulation.

In the present study, 1,869 skulls from the Hamann-Todd Collection were examined (macroscopically and by radiographs) for closure of the petroexoccipital articulation (jugular synchrondrosis). The results demonstrated the the petroexoccipital articulation underwent closure between 20 and 50 years of age in most human skulls evaluated. Approximately 7-10% of the human skulls underwent complete union of the petroexoccipital articulation before 20 years of age. In 5-9% of the population, the joint remained completely open. After 50 years of age, there was no increase in the frequency of individuals with incomplete closure. The frequency of "partial closure" was similar (4-8%) for all age groups (20-25, 30-35, 40-45, 50-55, 60-65, and 70+), excluding the 30-35 year old group (17.5%). The time interval necessary for closure to occur appeared to be very short. No significant differences in closure rates due to ethnic origin, gender, or laterality were noted. The utility of the pteroexoccipital articulation as an age estimator is discussed.

Adolescent↗
PubMed1997

Why do we fail in aging the skull from the sagittal suture?

The controversy over the reliability of ectocranial suture status (open vs. closed) as an age estimation stimulated the pursuit of Meindl and Lovejoy's suggestion (Meindl and Lovejoy [1985] Am. J. Phys. Anthropol. 68:57-66) for large scale analysis. The extent of the sagittal suture closure was assessed in 3,636 skulls from the Hamann-Todd and Terry collections. The debate over whether cranial suture ossification represents a pathologic or an age-predictable pathologic process also stimulated a comparison with age and two stress markers, hyperostosis frontalis interna and tuberculosis. Sagittal suture closure was found to be age-independent and sexually biased. The wide confidence intervals (for age) appear to preclude meaningful application of suture status for age determination. No correlation was found with the tested biological stressors.

Adult↗
PubMed1997

Recognition of sickle cell anemia in skeletal remains of children.

The present study discusses in detail the osteological changes associated with sickle cell anemia in children and their importance in differential diagnosis. Posterior calcaneal and specific articular surface disruptive metacarpal lesions are diagnostic for sickle cell anemia. Calvarial thickening, tibial and femoral cortical bone thickening, and bowing are of more limited utility in differential diagnosis. Granular osteoporosis, pelvic demineralization and rib broadening are nonspecific. Localized calvarial "ballooning," previously not described, may have diagnostic significance. Bone marrow hyperplastic response (porotic hyperostosis) in sickle cell anemia produces minimal radiologic changes contrasted with that observed in thalassemia and blood loss/hemolytic phenomenon. Two other issues, the osteological criteria for discriminating among the anemias and the purported relationship between porotic hyperostosis and iron deficiency anemia, are also discussed. There is sufficient information to properly diagnose the four major groups of anemias, and further, to establish that iron deficiency is only indirectly associated with porotic hyperostosis. The hyperproliferative bone marrow response (manifest as porotic hyperostosis) to blood loss or hemolysis exhausts iron stores, resulting in secondary iron deficiency.

Adolescent↗
PubMed1997

[Variation of sphenoidal angle of human skull in the course of aging].

The degree of the cranial base flexion is a major parameter in the study of the evolution of verbal communication in mankind. The variability of this area among modern humans has received little attention. In the present study, a sample of 330 modern human skulls have been used to characterize the changes in the angle of the cranial base flexion with age, and its possible relationships with gender and ethnic origin. Statistical analysis of the results show significant changes with age. Two conclusions emerged: i) the debate regarding Neanderthal speech should also consider the effect of age on the cranial base; and ii) the sphenoidal angle can be used as an ageing criterion in forensic and anthropological studies.

Adolescent↗
PubMed1997

Evidence of pin implantation as a means of verifying death during the Great Plague of Marseilles (1722).

The evidence obtained for the methods used in verification of death during the Great Plague of Marseilles in 1722 is presented here. This evidence was gathered during the excavation of a mass grave dating from this epidemic, and is based on two adjacent interments. The technique used at that time was the implantation of bronze pins into the toes. This method is precisely described in the medical treatises dating from this period, which list different death verification methods. The fear of "false death" and the burial of still living people characterized the end of the 17th and the 18th centuries. It should be noted that the main cause of apparent death is presented in the same medical treatises as the plague. This observation is the first anthropological evidence of the use of this forensic method to verify the fact of death.

Adult↗
PubMed1996

Size and location of the human temporomandibular joint.

The literature abounds with conflicting data on various morphometric aspects of the temporomandibular joint (TMJ). The purpose of this study was to observe the effects of sex, ethnic group, and edentulism on TMJ osseous morphology and to define possible factors which might influence variation in this structure. TMJs and related craniofacial structures were measured directly on 229 dry skulls and matching mandibles. Analysis of variance, principal component analysis, and cluster analysis were performed. Our results indicate that 1) the anteroposterior-related TMJ dimensions are independent of sex, ethnic group, and edentulism; 2) the transverse TMJ dimension is related to cranial breadth measures; and 3) the projected distance, along a midsagittal plane, between the TMJ and foramen magnum is independent of sex, ethnicity, and edentulism. It is our assertion that the TMJ must not be considered as a single morphological structure but rather viewed as a functional unit with component parts which are subordinate to completely different sets of influences.

Africa↗
PubMed1996

Factors affecting the rate and pattern of the first costal cartilage ossification.

In the present study, the extent of costochondral ossification of the first rib was determined from 78 chest roentgenograms of 13 healthy male soldiers subjected to a periodic follow-up. Roentgenography was performed at a mean interval of 2.9 years over a 15-year period. Mean subject age was 24 years at the commencement of the study and 37 years at its termination. Our results show that ossification of the first costal cartilage may start early in adult life and progress at individual rates. The ossification process proceeded from the costal toward the sternal end of the cartilage in an anteromedial direction. The morphological age-related changes ranged from the formation of small osseous islands in the cartilage to a complete ossification between the first rib and the sternum. The main conclusion of the study is that the degree of ossification of the first costal cartilage as an indicator of age does not provide the precision necessary for anthropological or forensic studies.

Adult↗