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The flat-end surfaces of dinosaur vertebral centra led to the presumption that intervertebral discs occupied the space between their vertebrae. A set of fused hadrosaur vertebrae allowed that hypothesis to be tested. The Tyrannosaurus rex responsible for this pathology did not escape unscathed. It left behind a tooth crown that had fractured. Fragments of that tooth were scattered through the intervertebral space, evidencing that there was no solid structure to impede its movement. That eliminates the possibility of an intervertebral disc and instead proves the presence of an articular space, similar to that in modern reptiles, but at variance to what is noted in birds. While avian cervical vertebral centra appear to be separated by diarthrodial joints, the preponderance of their thoracic vertebral centra is not separated by synovial joints., (© 2020 Blackwell Verlag GmbH.)

Temnospondyls, the largest group of Palaeozoic and Mesozoic amphibians, primitively possess rhachitomous vertebrae with multipartite centra (consisting of one horse-shoe-shaped inter- and paired pleurocentra). In a group of temnospondyls, the stereospondyls, the intercentra became pronounced and disc-like, whereas the pleurocentra were reduced. We report the presence of congenital vertebral malformations (hemi, wedge and block vertebrae) in Permian and Triassic temnospondyls, showing that defects of formation and segmentation in the tetrapod vertebral column represent a fundamental failure of somitogenesis that can be followed throughout tetrapod evolution. This is irrespective of the type of affected vertebra, that is, rhachitomous or stereospondylous, and all components of the vertebra can be involved (intercentrum, pleurocentrum and neural arch), either together or independently on their own. This is the oldest known occurrence of wedge vertebra and congenital block vertebra described in fossil tetrapods. The frequency of vertebral congenital malformations in amphibians appears unchanged from the Holocene., (© 2013 Blackwell Verlag GmbH.)

Gorilla gorilla and the less-studied G. beringei occupy very different, geographically separate habitats. We studied the occurrence of various forms of arthritis to examine possible nature/nurture causality. The macerated skeletons of 38 G. beringei and 99 G. gorilla individuals were examined macroscopically for the presence of articular and osseous pathologies. Contrasting with only isolated osteoarthritis and infectious arthritis was the frequent occurrence of a form of erosive arthritis associated with joint fusion. Twenty-one percent of the G. beringei and 20% of G. gorilla specimens were afflicted, which are statistically indistinguishable frequencies. While both had prominent axial disease, they differed in patterns of peripheral arthritis. Whereas G. beringei showed a pauciarticular pattern, the pattern in G. gorilla was more often polyarticular. Susceptibility to spondyloarthropathy was apparently genetically imprinted before Gorilla separated into G. gorilla and G. beringei. However, the different patterns of peripheral joint involvement suggest a causality resulting from lifestyle (e.g., the presence/absence or extent of knuckle walking) or a habitat-related infectious agent., ((c) 2005 Wiley-Liss, Inc.)

The character of arthritis has not received the same attention in Pan paniscus as it has in P. troglodytes. Reactive arthritis (a form of spondyloarthropathy) in the latter has been considered to be either a sexually transmitted or an infectious-agent diarrhea-related disorder. The unique sexual promiscuity of P. paniscus enables us to distinguish between those hypotheses. The macerated skeletons of 139 adult P. paniscus, P. troglodytes troglodytes, and P. troglodytes schweinfurthii were macroscopically analyzed for osseous and articular pathologies. The sex of the animal was recorded at the time of acquisition. Twenty-one percent of the P. paniscus, 28% of the P. t. troglodytes, and 27% of the P. t. schweinfurthii specimens had peripheral and central joint erosive disease characteristic of spondyloarthropathy. Subchondral pauciarticular distribution and reactive new bone clearly distinguish this disease from rheumatoid arthritis, osteoarthritis, and direct bone/joint infection. The fact that P. paniscus and P. t. troglodytes were similar in terms of disease frequency makes the notion of sexual transmission unlikely. While the frequencies of spondyloarthropathy were indistinguishable among all species/subspecies studied, the patterns of joint involvement were disparate. The Pan paniscus and P. t. troglodytes home ranges are geographically separate. We assessed possible habitat factors (e.g., exposure to specific infectious agents of diarrhea) by comparing P. paniscus and P. t. troglodytes with P. t. schweinfurthii. The latter shared similar patterns and habitats (separated by the Congo River) with P. paniscus. The explanation offered for habitat-specific patterns is differential bacterial exposure-most likely Shigella or Yersinia in P. paniscus and P. t. schweinfurthii., ((c) 2005 Wiley-Liss, Inc.)

This paper describes a phenomenon in the endocranial plate, which we have termed "serpens endocrania symmetrica" (SES), and discusses its value as a diagnostic tool. The affected discolored bone area exhibits disruption of the endocranial surface, lending it a maze-like appearance. Histological sections demonstrate that the process is limited to the most superficial portion of the endocranium, with no diploic and ectocranial involvement (sinus areas excepted). Adult skulls (n = 1,884) from the Hamann-Todd collection (HTH), housed at the Cleveland Museum of Natural History, were utilized for the present study. SES was recognized in 32 of the 1,884 skulls studied (1.7%). The frequency of SES among individuals reported to have died from tuberculosis (TB) was 4.4%. The rate of SES in the non-TB sample was only 0.53%. The locations were as follows: limited to sinus area, 28.1%; calvarium (excluding the sinuses), 46.9%; sinus + calvarium, 25.0%. SES was bilateral in 90.9% of cases. Twenty-five of the 32 individuals (78.1%) with SES in the HTH collection had tuberculosis specifically listed as the cause of death. Six of the other 7 individuals had infections other than TB. In 29 of the 32 individuals with SES, infection involved structures within the thorax. As SES was also associated with another osteological phenomenon known to represent pulmonary disease, i.e., hypertrophic osteoarthropathy (HOA; 68.0% of SES individuals also had HOA), SES may be of diagnostic value in paleopathology for the recognition of intrathoracic disease, and perhaps tuberculosis., (Copyright 2002 Wiley-Liss, Inc.)

The present study investigates a circumscribed bony overgrowth on the cranial vault, known as button osteoma (BtO) and referred to here as button lesion (BtL). We discuss its anthropological implications. Data on its histology, location, and population distribution (by age, race, and gender) are provided. Microscopically, BtL is composed of well-organized dense lamellated bone which is poorly vascularized and with very few osteocytes. It forms a dome-shaped roof over an underlying diploeized area which includes the ectocranial table. The frequency of BtL is similar in modern (37.6%) and archaeological (41.1%) populations, in blacks, whites, males, and females, and correlates with age. It is rare in nonhuman primates. Fifty-five percent of the human skulls studied by us had BtL only on the parietal, 23.6% on the frontal, and 3.6% on the occipital bones. Fifteen percent had BtL on both the frontal and parietal bones. No lateral preference was found. Most skulls with BtL (64.1%) had only one lesion, 20.4% had two BtL, and 15.4% demonstrated multiple BtL. The average number of button osteomas on an affected skull was 1.97. The frequency of large osteomas (0.5-1.0 cm) was similar in young and old age groups. The demographic characteristics of BtL, mainly its high frequency among ancient and modern populations, its independence of sex and race, its scarcity in other primates, and the fact that its macro- and microstruture are indicative of an hamartoma (and not an osteoma or exostosis) suggest an evolutionary background to the phenomenon., (Copyright 2002 Wiley-Liss, Inc.)

This study was conducted to characterize macroscopically and by conventional radiography the bony lesions in a case of Waldenstrom's macroglobulinemia and to compare and contrast it with those of the other major hematologic lymphoproliferative disorders, multiple myeloma and leukemia. Two varieties of lytic skeletal lesions were found in Waldenstrom's macroglobulinemia. One was sharply defined, spheroid lesions with smooth borders and effaced/erased trabeculae. The second was in the form of coalescing pits (holes) with smooth, minimally remodeled edges. The appearance combined features of multiple myeloma and leukemia, but were mutually exclusive in those diseases. Spheroid lesions with effaced edges were absent in leukemia, while pits were absent in multiple myeloma. Fronts of resorption were not noted in Waldenstrom's macroglobulinemia. The combination of some of the features of leukemia and myeloma appear to allow recognition of Waldenstrom's macroglobulinemia., (Copyright 2002 Wiley-Liss, Inc.)

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.

Slight variation in manifestation of different diseases may allow a single individual with one disease to mimic the "classic" appearance of another, as evidenced by the frequent confusion of spondyloarthropathy with rheumatoid arthritis. Analysis of population occurrence of arthritis (rather than isolated skeletons) facilitates more precise diagnosis. Northeast Africans living around 2,000 years before present were clearly afflicted with a form of spondyloarthropathy. Lack of inclusion of spondyloarthropathy in the differential diagnosis of erosive arthritis led to past misclassification of Nubians as having rheumatoid arthritis. While evidence of spondyloarthropathy abounds in the literature of human skeletal disease, pre-Columbian Old World rheumatoid arthritis is still elusive. The current study further documents the absence of rheumatoid arthritis in Nubians, supporting the hypothesis that rheumatoid arthritis began in the New World.

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.

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.

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.

A controlled study of the relationship of two standard clinical indicators of osteoarthritis and porosity failed to demonstrate a relationship. Porosity appears to be a curiosity that has no clinical correlation and is not a sign of an identifiable rheumatologic disorder. It should be deleted as an identifier for osteoarthritis.

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.

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.

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.

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.

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.

Characterization of the nature and skeletal distribution of gout was accomplished in a Chamoru (Chamorros) population with predilection to the disease. Uniform excavation by the gouty diathesis produces a punched-out appearance to these predominantly monarticular lesions. The lesion is distinct from that seen in rheumatoid arthritis, spondyloarthropathy, or infection. Reactive new bone formation in some gouty lesions also has an apparently unique, ivory-like discoloration (contrasted with the adjacent bone), which facilitates diagnosis.

The reliability of visual examination of defleshed bones was assessed for detection of postcranial metastatic disease in individuals known to have had cancer. This was compared with standard clinical radiologic techniques. The skeletons of 128 diagnosed cancer patients from an early 20th century autopsied skeletal collection (Hamann-Todd Collection) were examined. Radiologic examination detected evidence of metastatic disease in 33 individuals, compared to 11 by visual examination of the postcranial skeletons. Four of these cases were detected by both techniques. Blastic lesions were most commonly overlooked on visual examination, because they were localized to trabecular (internal bone) structures. The ilium was the most commonly affected bone, with lytic or blastic lesions detected in 30 of 33 individuals. While the proximal femur was affected in only nine individuals, x-ray of the proximal femur and ilium detected all individuals with postcranial evidence of metastatic disease. Skeletal distribution of metastases provides no clue to the location of origin or histologic subtype of the cancer. Survey of archeological human remains for metastatic cancer requires radiologic examination. Such skeletal surveys should x-ray at least the ilia and femora.

The paleopathological study of human osteological remains from the site of Semna South, of northern Sudan, revealed that about thirteen percent of this ancient Nubian population had diffuse idiopathic skeletal hyperostosis (DISH). As in modern cases, males were more affected than females. Two thousand years ago, ancient Nubian males had the same spinal problems elderly men have today.

Presence of spine and sacroiliac involvement and the nature and distribution of the erosive lesions allow definitive diagnosis of spondyloarthropathy. Thus, spondyloarthropathy was identified in Theropithecus, Papio, Cercopithecus, Macaca, Colobus, Presbytis, and Hylobates. Only monarticular erosive disease was present in prosimians, precluding a diagnosis of spondyloarthropathy for that group. The distribution of erosive disease and axial joint involvement in 1,349 non-prosimian Old World primates is quite characteristic of that noted in human psoriatic arthritis. While Reiter's syndrome must also be considered, the histologic appearance of skin lesions in Macaca is characteristic of psoriasis. Evidence of spondyloarthropathy abounds in the literature of primate skeletal disease. Environmentally based contagions may be important in the pathophysiology of spondyloarthropathy. The wide geographic distribution of the phenomena in monkeys suggests a "panendemic," with limited individual susceptibility (compared to that noted in gorillas and chimpanzees). Identical occurrence of erosive arthritis/spondyloarthropathy in free-ranging and artificially restrained animals suggests that spondyloarthropathy can validly be studied in artificially restrained populations. This perspective should allow application of human therapeutic approaches to and perhaps improve the quality of life for artificially restrained, afflicted individuals.

Uncertainties as to the nature and implications of osteoarthritis and calcium pyrophosphate deposition disease (CPPD) in primates were subject to critical review through examination of 153 prosimians and 1,250 Old World non-prosimian primates. Osteoarthritis, calcium pyrophosphate deposition disease, and infectious arthritis/osteomyelitis were relatively rare phenomena, affecting only 1.7% and 2.5%, respectively, of free-ranging prosimians and other Old World non-prosimian primates. Frequency of infection in Indri and Presbytis appears to reflect a unique susceptibility or exposure. Papio may have a unique predisposition to CPPD. The dichotomy (frequency and joint distribution) between free-ranging and artificially restrained animals suggests caution in interpretation of osteoarthritis or CPPD in non-free-ranging animals.

Erosive changes and syndesmophyte formation, characteristics of spondyloarthropathy, were present in 79/2906 skeletons in the Todd Collection. Holistic assessment of this defined population allowed it to be distinguished from rheumatoid and other erosive forms of arthritis. Characterization of the nature and distribution of osseous alterations in a contemporary skeletal population allowed development of a standard for recognition of the disease in skeletal populations.

Diagnosis of diseases of bone, without benefit of soft tissue, in vivo observation, or blood component analysis requires the development of new criteria for diagnosis. Analyzing chimpanzee skeletal populations, applying such criteria (e.g., lesion character, distribution, radiologic appearance, and sex ratios), revealed a picture indistinguishable from human spondyloarthropathy. As Africa has been shown to manifest this condition in indigenous human, chimpanzee, and lowland gorilla populations, the possibility of a non-species specific etiology is suggested., (Copyright © 1991 Wiley‐Liss, Inc., A Wiley Company.)

Examination of isolated bones from patients with unequivocal rheumatoid arthritis provides only a glimpse of the disease but has been the only "gold standard" for recognition of osseous lesions as compatible with the diagnosis of rheumatoid arthritis. Documentation of skeletal pathologic changes in confidently diagnosed individuals has been a major missing link in the transition from clinical to skeletal analysis. Availability of appropriate skeletal material from two patients with long-standing, well-documented rheumatoid arthritis provided the opportunity for acquiring such information. The osseous appearance, skeletal distribution, and distinguishing features of rheumatoid arthritis "in the buff" were delineated in two contemporary patients and in a skeletal population of 2,906 individuals. The preconceived notion of anticipated severity of disease has hereby been tested and found wanting. Severe lesions are not recognizable or distinguishable from artifact in relatively fragile rheumatoid arthritis-affected bones, whether freshly prepared or remotely sampled. Characterization of the nature and epidemiology of osseous alterations in two contemporary skeletal populations permitted the development of a standard for recognition of the disease in skeletal populations.

We have characterized 52 consecutive patients fulfilling 4 or more of the American Rheumatism Association criteria for systemic lupus erythematosus in order to provide, for the first time, a homogeneous sample for statistical comparison of antinuclear antibody (ANA)-positive and ANA-negative groups. Ten patients (19%) were seronegative. There was no significant difference in age, disease activity, organ system involvement, erythrocyte sedimentation rate, immune complex levels, or C3 levels. The ANA-negative group showed a higher incidence of involvement for whites and men. Leukopenia, lower levels of antibody to DNA, and higher C4 levels were also characteristic of the ANA-negative group.