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Ulna
Selected AbstractsA shortening of the manus precedes the attenuation of other wing-bone elements in the evolution of flightlessness in birdsACTA ZOOLOGICA, Issue 1 2010R. L. Nudds Abstract Nudds, R. L. and Slove Davidson, J. 2010. A shortening of the manus precedes the attenuation of other wing-bone elements in the evolution of flightlessness in birds. ,Acta Zoologica (Stockholm) 91: 115,122 This is the first study to present evidence for a general pattern of wing-bone attenuation during the early stages of the evolution of flightlessness. A comparative analysis using phylogenetic independent contrasts showed that in families that contain both flighted (volant) and flightless species, the volant species have shorter wings and total-arm (humerus + ulna + manus) lengths relative to their body masses than the species within their wholly volant sister families. A shortening of the manus may typify the early stages of the evolution of flightlessness, with the humerus and ulna attenuating later, perhaps because of their role in maintaining the position of the aerodynamically important alula. A shorter wing relative to body mass was not the result of the inverse (i.e. heavier body mass relative to wing length) because mean body masses of volant members of flightless families were similar to or lower than those of their wholly volant sister families. Despite finding a common trend in the wing morphologies of volant members of flightless families, it seems unlikely that a general model of selection pressures driving the evolution of flightlessness exists. At the very least, a dichotomy between those birds that have lost the ability to fly in order to gain the ability to swim and terrestrial forms, may persist. [source] Appendicular skeleton in Bachia bicolor (Squamata: Gymnophthalmidae): osteology, limb reduction and postnatal skeletal ontogenyACTA ZOOLOGICA, Issue 1 2009Adriana Jerez Abstract The osteology of the appendicular skeleton and its postnatal development are described in Bachia bicolor, a serpentiform lizard with reduced limbs. The pectoral girdle is well developed and the forelimb consists of a humerus, ulna, radius, five carpal elements (ulnare, radiale, distal carpals 4,3, centrale), four metacarpals (II, III, IV, V) and phalanges (phalangeal formula X-2-2-2-2). In the hindlimb, the femur is small and slender, and articulates distally with a series of ossified amorphous and extremely reduced elements that correspond to a fibula, tibia and proximal and distal tarsals 4 and 3. The pelvic girdle consists of ischium, pubis and ilium, but its two halves are widely separated; the ilium is the least reduced element. We describe the ossification and development during postnatal skeletal ontogeny, especially of epiphyseal secondary centres, ossifications of carpal elements, apophyseal ossifications and sesamoids. Compared to other squamates, B. bicolor shows an overall reduction in limb size, an absence of skeletal elements, a fusion of carpal elements, an early differentiation of apophyseal centres, and a low number of sesamoids and apophyseal centres. These observations suggest that the reductions are produced by heterochronic changes during postnatal development and probably during embryonic development; therefore the appendicular skeleton exhibits a pattern of paedomorphic features. [source] Fore limb bones of late Pleistocene dwarf hippopotamuses (Mammalia, Cetartiodactyla) from Madagascar previously determined as belonging to the crocodylid Voay Brochu, 2007FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 2 2010Oliver Hampe Abstract A humerus and two radii of juvenile dwarf hippopotamuses are redescribed. The subfossil bones from the collection of the Museum für Naturkunde Berlin were erroneously assigned to the horned crocodile Voay robustus (Grandidier & Vaillant, 1872) by Bickelmann & Klein (2009). All three limb bones presented here belong to immature animals. The epiphyses are not fused, except the proximal extremity of the right radius; and the radius and ulna are also unfused. The two radii are from individuals of different size, whereas the left radius and the humerus are from animals of similar size. Morphologically, the limb bones cannot be identified to species level. A tentative assignment to Hippopotamus madagascariensis is discussed based on the knowledge of the geographic origin on the island. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Fly or die: the role of fat stores in the growth and development of Grey-headed Albatross Diomedea chrysostoma chicksIBIS, Issue 2 2000KEITH REID Chicks of albatrosses, like other Procellariiformes, become independent at a mass similar to their parents but during growth attain a peak mass some 30% or more greater, before losing mass prior to fledging. The current views are that this high peak mass represents chicks storing fat reserves as an energy sink, or as an insurance against periodic food scarcity, or as a Consequence of natural stochastic variation in provisioning rate. We analysed growth and body composition of Grey-headed Albatross Diomedea chrysostoma chicks at Bird Island, South Georgia in 1984 and 1986, two years of very different food availability. In 1984 when overall breeding success was only 28% (the lowest in 20 years and less than halt that in 1986), chicks were significantly smaller in terms of peak mass (by 37%), primary length (by 25%), liver, lung, heart and kidney size (by 18,34%) and fat (by 75,80%) but not significantly different in terms of skeletal (tarsus, culmen, ulna, sternum) or muscle (pectoral, leg) size. Despite these differences, there were some important similarities in the patterns of growth in both years. Up to the attainment of peak mass, most of the growth of organs and of skeletal structures was completed and little fat was deposited. In the remaining part of the chick-rearing period, feather growth and acquisition of fat stores were undertaken. Thus Grey-headed Albatross chicks begin to acquire substantial fat stores only during the later part of the development period; this is contrary to the predictions of any of the existing hypotheses concerning provisioning patterns and the role of fat stores in Procellariiformes. We propose that the deposition of fat in the later stages of chick growth is an adaptation to: (a) ensure against energy demands and/or nutritional stress affecting the quality of flight feathers (many of which are not renewed for up to three years after fledging); and (b) provide an energy reserve for chicks to use in the critical period immediately after independence. [source] Evidence of amputation as medical treatment in ancient EgyptINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2010T. L. Dupras Abstract The use of surgical techniques in ancient Egyptian medicine has only been suggested indirectly through ancient medical texts and iconography, and there is no evidence of amputation as a means of therapeutic medical treatment. This paper presents four cases of amputation from the archaeological site of Dayr al-Barsh,, Egypt. Two of the cases (dated to the First Intermediate and Middle Kingdom periods, respectively) are from individuals that display bilateral amputations of the feet, one through the metatarso-phalangeal joints, the other a transmetatarsal amputation. The exact reason for the amputation, perhaps from trauma or disease, is unknown. The particular healing patterns of the distal ends of the amputations suggest these individuals used foot binding or prosthetic devices. Another case represents a healed amputation of the left ulna near the elbow, dated to the Old Kingdom. The final case represents a perimortem amputation of the distal end of the right humerus. The exact date of this individual is unknown, but most likely pertains to the Old Kingdom or First Intermediate period. This individual seems to have suffered a traumatic incident shortly before death, sustaining many fractures, including a butterfly fracture on the right humerus. Several cut marks were identified on top of the butterfly fracture, indicating amputation of the arm at this point. All four cases support the hypothesis that the ancient Egyptians did use amputation as a therapeutic medical treatment for particular diseases or trauma. Copyright © 2009 John Wiley & Sons, Ltd. [source] The treatment of leprosy in 19th-century London: a case study from St Marylebone cemeteryINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2009D. WalkerArticle first published online: 19 MAY 200 Abstract A young adult male, context [825], exhibiting a suite of proliferative and erosive skeletal changes, was excavated from the old burial ground of St Marylebone, London, in 2005 by the Museum of London Archaeology Service (MoLAS). Although pathognomonic rhinomaxillary changes were absent, a number of lesions were of a type previously recorded in individuals suffering from lepromatous leprosy, including resorption of the alveolar process of the maxillae and the digits of the right hand, osteomyelitis in the left ulna and collapse of the left ankle. Whilst this infectious disease was widespread in medieval Britain, it had declined by the 19th century, and has been identified in only one other post-medieval archaeological context. The right leg of [825] had been surgically amputated. This form of intervention was a recognised treatment for the complications of the disease, where neuropathic damage of limbs led to life-threatening infection. The healing of the amputation demonstrates the success of the operation, and the skill of the surgeon. Although the identity of the affected individual is unknown, burial within St Marylebone cemetery implies a level of status not frequently associated with leprosy sufferers in the past. Copyright © 2008 John Wiley & Sons, Ltd. [source] Trauma in the city of Kerma: ancient versus modern injury patternsINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1 2004M. Judd Abstract Injuries, whether accidental or intentional, have incapacitated humans and their primordial ancestors throughout time, although the injury mechanisms have become increasingly more technologically sophisticated. Interpretation of injury aetiology among past peoples is challenging, and often impossible, however, clinical research from developing countries provides a useful analogy with which to evaluate trauma or health patterns of an ancient society. This paper presents a systematic analysis of cranial and postcranial skeletal trauma among 223 adults who were excavated by George Reisner in 1923 from the city of Kerma (1750,1550 BC), Egypt's ancient nemesis in the struggle for control of the Nile River trade route. A total of 156 injuries (fractures, dislocations and muscle pulls among the skull, long bones, extremities and torso) were observed among 88 individuals, 48 of whom had one injury only. The skull was the most frequently traumatized element (11.2%) followed by the ulna (8.3%); 2.4% (48/2029) long bones were fractured. The modal distribution of the Kerma fractures was compared to the fracture distributions of two samples from India and Nigeria where falls were the most common cause of injury. Some characteristics of the three injury patterns were shared: males suffered the greatest frequency of injury, the economically active people (25 to 50 years of age) presented the most injuries among adults, and a small proportion of the victims had more than one major injury. However, the Kerma distribution of the fractured bones varied dramatically from the clinical injury distributions: the ulna and skull were among the least frequently injured bones in the modern samples, while the radius, humerus and lower leg were the most commonly traumatized elements among the modern people, but rare among the ancients. The configuration of the ulna and skull injuries at Kerma was characteristic of those associated with blunt force trauma in other clinical assessments and the absence of these specific lesions from the modern samples where accident was the primary injury mechanism presents a persuasive argument for interpersonal violence among the ancient Kerma people. Copyright © 2004 John Wiley & Sons, Ltd. [source] Confirmation of the presence of Mycobacterium tuberculosis complex-specific DNA in three archaeological specimensINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2002Mark Spigelman Abstract This journal published the first reported identification of Mycobacterium tuberculosis complex (MTB) DNA in ancient human remains but concerns were raised about the article two years after publication. These were based on methodology which, in the field of ancient DNA, was still developing. Here we present a re-examination of the 1993 research conducted on three specimens which exhibited palaeopathologies indicative of tuberculosis. The specimens were: an ulna from pre-European-contact Borneo, a spine from Byzantine Turkey, and a lumbar-sacral spine from 17th century Scotland. There was insufficient material to permit re-examination of all of the original samples. The earlier results were confirmed in two independent laboratories using different methodologies. MTB DNA complex-specific DNA amplicons were obtained, and sequenced in both laboratories, in a re-analysis of samples which supported the earlier findings. Copyright © 2002 John Wiley & Sons, Ltd. [source] Distributional Patterns of Diatoms and Limnodrilus Oligochaetes in a Kenyan Dry Streambed Following the 1999,2000 Drought ConditionsINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 2 2005Jude M. Mathooko Abstract Drought is a natural phenomenon experienced by many intermittent and also seasonal lotic systems. It has diverse effects on the structure and distribution of biological communities through habitat transition from wetted to terrestrial conditions. The Njoro River, a tropical stream, was drought-stressed between late 1999 and mid 2000, providing an opportunity to sample and describe the distributional patterns of diatoms and Limnodrilus oligochaetes in the vertical sediment profile. The dispersion of Limnodrilus oligochaetes with sediment depth profile varied from quasi-random (i.e. exponent k of the negative binomial distribution >2.0 or <0) at the surface to strong aggregation (0 < k < 1.0) in the deeper sediments. Diatoms were heterogenous, with most species contributing less than 1% of all the diatoms collected from the riverbed. Contagious dispersion was a common feature among the diatom species. The distribution of Fragilaria ulna was largely quasi-random in all sites, with Nitzschia amphibia and Cocconeis placentula demonstrating quasi-random distribution in the Kerma vertical sediment profile. Escape from stranding to deeper sediment strata as the drought progressed was not a universal response among the diatom species. Our results showed that drought-stress altered the structure of biological assemblages and also emphasized the need for the management of tropical lotic systems and their catchments for flow permanence. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] An immunohistochemical study of the triangular fibrocartilage complex of the wrist: regional variations in cartilage phenotypeJOURNAL OF ANATOMY, Issue 1 2007S. Milz Abstract The triangular fibrocartilage complex (TFCC) transmits load from the wrist to the ulna and stabilizes the distal radioulnar joint. Damage to it is a major cause of wrist pain. Although its basic structure is well established, little is known of its molecular composition. We have analysed the immunohistochemical labelling pattern of the extracellular matrix of the articular disc and the meniscal homologue of the TFCC in nine elderly individuals (age range 69,96 years), using a panel of monoclonal antibodies directed against collagens, glycosaminoglycans, proteoglycans and cartilage oligomeric matrix protein (COMP). Although many of the molecules (types I, III and VI collagen, chondroitin 4 sulphate, dermatan sulphate and keratan sulphate, the oversulphated epitope of chondroitin 6 sulphate, versican and COMP) were found in all parts of the TFCC, aggrecan, link protein and type II collagen were restricted to the articular disc and to entheses. They were thus not a feature of the meniscal homologue. The shift in tissue phenotype within the TFCC, from a fibrocartilaginous articular disc to a more fibrous meniscal homologue, correlates with biomechanical data suggesting that the radial region is stiff and subject to considerable stress concentration. The presence of aggrecan, link protein and type II collagen in the articular disc could explain why the TFCC is destroyed in rheumatoid arthritis, given that it has been suggested that autoimmunity to these antigens results in the destruction of articular cartilage. The differential distribution of aggrecan within the TFCC is likely to be reflected by regional differences in water content and mobility on the radial and ulnar side. This needs to be taken into account in the design of improved MRI protocols for visualizing this ulnocarpal complex of the wrist. [source] Hand development and sequence of ossification in the forelimb of the European shrew Crocidura russula (Soricidae) and comparisons across therian mammalsJOURNAL OF ANATOMY, Issue 2 2004Jan Prochel Abstract Hand development in the European shrew Crocidura russula is described, based on the examination of a cleared and double-stained ontogenetic series and histological sections of a c. 20-day-old embryo and a neonate. In the embryo all carpal elements are still mesenchymal condensations, and there are three more elements than in the adult stage: the ,lunatum', which fuses with the scaphoid around birth; a centrale, which either fuses with another carpal element or just disappears later in ontogeny; and the anlage of an element that later fuses with the radius. Carpal arrangement in the neonate and the adult is the same. In order to compare the relative timing of the onset of ossification in forelimb bones in C. russula with that of other therians, we built up two matrices of events based on two sets of data and used the event-pair method. In the first analysis, ossification of forelimb elements in general was examined, including that of the humerus, radius, ulna, the first carpal and metacarpal to ossify, and the phalanges of the third digit. The second analysis included each carpal, humerus, radius, ulna, the first metacarpal and the first phalanx to ossify. Some characters (= event,pairs) provide synapomorphies for some clades examined. There have been some shifts in the timing of ossification apparently not caused by ecological and/or environmental influences. In two species (Oryctolagus and Myotis), there is a tendency to start the ossification of the carpals relatively earlier than in all other species examined, the sauropsid outgroups included. [source] Bisphosphonate-Induced Osteopetrosis: Novel Bone Modeling Defects, Metaphyseal Osteopenia, and Osteosclerosis Fractures After Drug Exposure Ceases,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2008Michael P Whyte Abstract In 2003, we reported on a 12-yr-old boy who had developed osteopetrosis (OPT) while receiving pamidronate (PMD) for idiopathic bone pain and enigmatic elevation in circulating bone alkaline phosphatase. Now 17 yr of age, he was re-evaluated 6.5 yr after PMD exposure stopped. Our patient described less bone pain but further limb fractures. His growth plates were fused, yet hyperphosphatasemia persisted. Radiographs documented interval fractures of a metacarpal, an osteosclerotic distal radius, and a dense diaphyseal segment of an ulna where a "chalkstick" break remained incompletely healed after 2 yr. There was new L4 spondylolysis, and previous L5 spondylolysis had caused spondylolisthesis. Modeling disturbances of OPT persisted, but partial recovery was shown by metaphyseal surfaces with a unique concave shape. Metaphyseal osteosclerosis had remodeled imperfectly to become focal areas of dense, diaphyseal bone. Newer metaphyseal bone was unexpectedly osteopenic, especially in his distal femurs where cortices were thin and a paucity of trabeculae was documented by CT. Femoral necks had become short and wide with an abnormal contour. A "bone-within-bone" configuration was now present throughout his skeleton. In vertebrae, endplates were thin, and trabecular osteopenia was present central and peripheral to the bands of osteosclerosis. BMD Z-scores assessed by DXA had decreased into the normal range in his spine, hip, and whole body. Iliac crest biopsy showed active bone formation, with much less accumulated primary spongiosa than during the PMD infusions. Osteoclasts that had been dysmorphic, round cells without polarization and off of bone surfaces were now unremarkable in number, location, and appearance. In conclusion, bisphosphonate toxicity during childhood can impair skeletal modeling and remodeling with structural changes that evolve and carry into adult life. [source] The Effect of In Vivo Mechanical Loading on Estrogen Receptor , Expression in Rat Ulnar Osteocytes,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2002P. J. Ehrlich Abstract The presence of estrogen receptor , (ER,) in osteocytes was identified immunocytochemically in transverse sections from 560 to 860 ,m distal to the midshaft of normal neonatal and adult male and female rat ulnas (n = 3 of each) and from adult male rat ulnas that had been exposed to 10 days of in vivo daily 10-minute periods of cyclic loading producing peak strains of either ,3000 (n = 3) or ,4000 microstrain (n = 5). Each animal ambulated normally between loading periods, and its contralateral ulna was used as a control. In animals in which limbs were subject to normal locomotor loading alone, 14 ±1.2% SEM of all osteocytes in each bone section were ER, positive. There was no influence of either gender (p = 0.725) or age (p = 0.577) and no interaction between them (p = 0.658). In bones in which normal locomotion was supplemented by short periods of artificial loading, fewer osteocytes expressed ER, (7.5 ± 0.91% SEM) than in contralateral control limbs, which received locomotor loading alone (14 ± 1.68% SEM; p = 0.01; median difference, 6.43; 95% CI, 2.60, 10.25). The distribution of osteocytes expressing ER, was uniform across all sections and thus did not reflect local peak strain magnitude. This suggests that osteocytes respond to strain as a population, rather than as individual strain-responsive cells. These data are consistent with the hypothesis that ER, is involved in bone cells' responses to mechanical strain. High strains appear to decrease ER, expression. In osteoporotic bone, the high strains assumed to accompany postmenopausal bone loss may reduce ER, levels and therefore impair the capacity for appropriate adaptive remodeling. [source] An Evaluation of Determination of Handedness Using Standard Osteological Measurements,JOURNAL OF FORENSIC SCIENCES, Issue 4 2008Marie Elaine Danforth Ph.D. Abstract:, Numerous studies have assessed side dominance assuming arm bones on the side of handedness will be larger, but concerns over sample size or replicability of measurements usually emerged. Attempting to improve upon these limitations, this investigation analyzes patterns of side difference for standard length and transverse dimensions of the scapula, clavicle, humerus, ulna, and radius for 137 individuals of known handedness. The results showed that with few exceptions, the right side of the skeleton was consistently larger in most individuals regardless of side dominance. Combinations of other measurements previously suggested to be indicative of handedness as well as the use of discriminant analysis also failed to provide reliable estimators. These findings are likely related to the fact that activities of modern individuals are generally not sufficiently unilateral in their stresses to cause asymmetrical development in the arm bones. Therefore, it is recommended that other means be developed to assess side dominance. [source] The lissamphibian humerus and elbow joint, and the origins of modern amphibiansJOURNAL OF MORPHOLOGY, Issue 12 2009Trond Sigurdsen Abstract The origins and evolution of the three major clades of modern amphibians are still a source of controversy, and no general consensus exists as to their relationship to the various known Paleozoic taxa. This may indicate that additional character complexes should be studied to resolve their phylogenetic relationship. The salamander elbow joint has been fundamentally misinterpreted in previous morphological descriptions. In caudates and anurans, both the radius and ulna (fused in anurans) articulate with the characteristically large capitulum (radial condyle), although part of the ulnar articulating surface fits into to the smooth trochlear region. The salamander "ulnar condyle" of previous descriptions is in fact the entepicondyle. The condition seen in batrachians (i.e., salamanders and frogs) may be a lissamphibian synapomorphy because the elbow region of the primitive fossil caecilian Eocaecilia resembles those of frogs and salamanders. In addition to the large and bulbous capitulum, all lissamphibian humeri lack an entepicondylar foramen, and possess a distally pointing entepicondyle, a low and rounded ectepicondyle, and an elongated shaft. These characters are identified in key fossil forms to assess the support for the different hypotheses proposed for the evolutionary origins of lissamphibians. Temnospondyli is the only group of early tetrapods that shows a progressive evolution of lissamphibian traits in the humerus and elbow joint. Furthermore, among Paleozoic taxa, the dissorophoid temnospondyl Doleserpeton annectens is the only taxon that has the full set of humeral features shared by all lissamphibians. These results add support for the theory of a monophyletic origin of lissamphibians from dissorophoidtemnospondyls. J. Morphol., 2009. © 2009 Wiley-Liss, Inc. [source] Mathematical modeling of appendicular bone growth in glaucous-winged gullsJOURNAL OF MORPHOLOGY, Issue 1 2009James L. Hayward Abstract Development of locomotor activity is crucial in tetrapods. In birds, this development leads to different functions for hindlimbs and forelimbs. The emergence of walking and flying as very different complex behavior patterns only weeks after hatching provides an interesting case study in animal development. We measured the diaphyseal lengths and midshaft diameters of three wing bones (humerus, ulna, and carpometacarpus) and three leg bones (femur, tibiotarsus, and tarsometatarsus) of 79 juvenile (ages 0,42 days) and 13 adult glaucous-winged gulls (Larus glaucescens), a semiprecocial species. From a suite of nine alternative mathematical models, we used information-theoretic criteria to determine the best model(s) for length and diameter of each bone as a function of age; that is, we determined the model(s) that obtained the best tradeoff between the minimized sum of squared residuals and the number of parameters used to fit the model. The Janoschek and Holling III models best described bone growth, with at least one of these models yielding an R2 , 0.94 for every dimension except tarsometatarsus diameter (R2 = 0.87). We used the best growth models to construct accurate allometric comparisons of the bones. Early maximal absolute growth rates characterize the humerus, femur, and tarsometatarsus, bones that assume adult-type support functions relatively early during juvenile development. Leg bone lengths exhibit more rapid but less sustained relative growth than wing bone lengths. Wing bone diameters are initially smaller than leg bone diameters, although this relationship is reversed by fledging. Wing bones and the femur approach adult length by fledging but continue to increase in diameter past fledging; the tibiotarsus and tarsometatarsus approach both adult length and diameter by fledging. In short, the pattern of bone growth in this semiprecocial species reflects the changing behavioral needs of the developing organism. J. Morphol., 2009. © 2008 Wiley-Liss, Inc. [source] The effects of partial and total interosseous membrane transection on load sharing in the cadaver forearmJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2001Michael F. Shepard This study was performed to examine the effects of partial and total transection of the interosseous membrane (IOM) on load transfer in the forearm. Twenty fresh frozen forearms were instrumented with custom designed load cells placed in the proximal radius and distal ulna. Simultaneous measurements of load cell forces, radial head displacement relative to the capitellum, and local tension within the central band of the IOM were made as the wrist was loaded to 134 N with the forearm at 90° of elbow flexion and in neutral pronation supination. For valgus elbow alignment (radial head contacting the capitellum), mean force carried by the distal ulna was 7.1% of the applied wrist force and mean force transferred from radius to ulna through the IOM was 4.4%. For varus elbow alignment (mean 2.0 mm gap between the radial head and capitellum), mean distal ulna force was 28% and mean IOM force was 51%. Section of the proximal and distal one-thirds of the IOM had no significant effect upon mean distal ulnar force or mean IOM force. Total IOM section significantly increased mean distal ulnar force for varus elbow alignment in all wrist positions tested. The mean level of applied wrist force necessary to close the varus gap (89 N) decreased significantly after both partial IOM section (71 N) and total IOM section (25 N). The IOM became loaded only when the radius displaced proximally relative to the ulna, closing the gap between the radius and capitellum. As the radius displaced proximally, the wrist becomes increasingly ulnar positive, which in turn leads to direct loading of the distal ulna. This shift of force to the distal ulna could present clinically as ulnar sided wrist pain or as ulnar impaction after IOM injury. © 2001 Orthopaedic Research Society. Punlished by Elsevier Science Ltd. All rights reserved. [source] CURRENT VARIABILITY SHAPES MORPHOLOGICAL COMPLEXITY IN COLONIAL STREAM DIATOMSJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Passy, S. I.1,2 & Freehafer, D.2 1Department of Biology, Rensselaer Polytechnic Institute, Troy, NY 12180; 2US Geological Survey, 425 Jordan Rd., Troy, NY 12180-8349 USA On August 27, 1999 diatoms were sampled, and current velocity was measured at 81 locations on a regular square sampling grid in an unshaded, cobble-bottom reach of White Creek, NY. The grid had an extent of 16 m2, interval, the distance between neighboring sampling points, of 0.5 m, and grain size, the size of the elementary sampling unit, of 0.01 m2. Six of the seven dominant benthic diatoms were colonial forms, including Diatoma vulgaris, Fragilaria capucina, F. crotonensis, Gomphoneis minuta, Melosira varians, and Synedra ulna. Their morphology and distribution were investigated from the perspective of fractal geometry and stream ecology, respectively. Fractal dimension of diatom colonies, indicative of their shape complexity, ranged from 1.06 to 1.54, demonstrating vast morphological variation from simple geometric shapes to complex outlines. The relative abundance of the six diatoms was regressed against current regime, which ranged from 0.03 to 0.66 m, s -1. All regression models were significant at P < 0.05 and explained between 55% and 94% of the variation in diatom distribution. The diatom niche breadth, i.e. the amount of environmental variability a species can tolerate, was defined from these models and showed substantial variation, from 5 to 14. The regression model of fractal dimension against niche breadth was significant and explained 76% of colonial shape variation, revealing a strong relationship between diatom colonial complexity and habitat variability. This finding suggests that environmental variability could create highly complex colonial morphologies in benthic diatoms as an evo-lutionary strategy for survival in unpredictable environments. [source] Ulnocarpal arthrodesis and limb lengthening for the management of radial agenesis in a dogJOURNAL OF SMALL ANIMAL PRACTICE, Issue 10 2007W. M McKee Radial agenesis was diagnosed in a nine-week-old boxer. An ulnocarpal arthrodesis was performed when six months of age to improve limb alignment and enable weight bearing. When the dog was 10 months old, a hinged circular fixator was applied to the limb to gradually lengthen the ulna and correct angular and rotational deformity. The fixator was removed at 16 months of age. At this time, there was 1·7 cm (6 per cent) shortening of the affected antebrachium-metacarpus and 2·6 cm (15 per cent) compensatory overgrowth of the humerus compared with the contralateral limb. Inability to extend the digits was a complication that improved with physiotherapy. Follow-up at 23 months of age showed good limb use when walking and running. Radiographs of the elbow showed periarticular osteophytes and subcoronoid sclerosis of the ulna. [source] Co-existence of ununited anconeal process and fragmented medial coronoid process of the ulna in the dogJOURNAL OF SMALL ANIMAL PRACTICE, Issue 2 2006A. Meyer-Lindenberg Objectives: To determine the incidence of fragmented medial coronoid process of the ulna in dogs with ununited anconeal process. The efficacy of presurgical radiography to diagnose the co-existence of these diseases was also investigated. Methods: One hundred and fifty-five joints from 137 dogs with ununited anconeal process were included in the study. For the radiographic examinations, an extended mediolateral projection and a craniolateral-caudomedial oblique projection of each elbow joint were taken before surgery. Inspection of the medial part of the joint was carried out either by arthrotomy or arthroscopy. Results: Seventy-two per cent of the dogs were German shepherd dogs. In 25 joints (16 per cent) a fragmented medial coronoid process was diagnosed and removed via arthrotomy or arthroscopy. The co-existence of a fragmented medial coronoid process was diagnosed correctly in only 13 cases (52 per cent) by radiography. In five of these cases with advanced osteoarthritis, the fragment was directly visible because of its dislocation. Compared with published information, the occurrence of ununited anconeal process with fragmented medial coronoid process is noted more frequently in the present study. Clinical Significance: It can be summarised that if ununited anconeal process is present, it is not usually possible to clearly identify fragmented medial coronoid process by radiography. Therefore, it is important to be able to inspect the medial aspect of the joint concerned during surgery. [source] Maintenance of bone mass and architecture in denning black bears (Ursus americanus)JOURNAL OF ZOOLOGY, Issue 4 2004Connor K. Pardy Abstract Bone mass is dramatically compromised during periods of weightlessness, inactivity, or bed rest. Animals that hibernate reduce their body temperature, heart rate and metabolic activity, and likewise lower bone turnover activity during their immobile state. Black bears Ursus americanus, however, do not hibernate, but rather overwinter by denning during which they maintain a nearly normal functional heart rate, cardiac output and temperature. Furthermore, markers of bone turnover in black bears are maintained during denning periods. Thus, the purpose of this work was to determine if the denning state of relative immobility in black bears results in changes in bone mass and bone architectural structure. Harvested forelimbs (ulna and radius) were compared between pre- and post-denning black bears using X-ray imaging, dual energy X-ray absorptiometry, and micro-computed tomography to quantify total distal forelimb bone mineral density, cancellous bone mineral density, bone mineral content, bone volume fraction, degree of anisotropy, structure model index, and trabecular thickness. No significant differences in any of the measured parameters were found in comparing radius and ulna from autumn and spring bears in this cross-sectional sample, suggesting that black bears did not experience a significant change in bone mass or architecture during denning. The statistical power for detecting a significant difference (P, 0.05) for this sample was 0.8. The specific mechanism by which the preservation of bone was attained may be related to skeletal muscle interaction or circulating systemic hormones. [source] BILATERAL DIRECTIONAL ASYMMETRY OF THE APPENDICULAR SKELETON OF THE HARBOR PORPOISE (PHOCOENA PHOCOENA)MARINE MAMMAL SCIENCE, Issue 3 2005Anders Galatius Abstract Directional asymmetry (DA) of the lengths, diameters, and masses of the scapula, humerus, radius, and ulna were analyzed on a sample of 213 harbor porpoises from Denmark and West Greenland. The levels of DA were consistent across yearlings and older animals, mature and immature animals, sexes, and populations. All investigated variables showed significant DA favoring the right side. For the pooled sample, DA of lengths ranged from 0.2% SE 0.1 (ulna) to 1.2% SE 0.1 (scapula). DAs of diameters were 1.5% SE 0.2 for the humerus, 0.6% SE 0.1 for the radius, and 1.3% SE 0.2 for the ulna. DA of mass ranged from 2.8% SE 0.5 (humerus) to 4.3% SE 0.7 (ulna). The humerus and ulna had significantly larger mean diameter/ length ratios on the right side than the left, making them more robust. The large DA of scapula length indicates larger muscle mass associated with the right flipper, while the generally more robust right humerii and ulnae may be designed for higher levels of mechanical stress. These DAs and the examples of lateralized behavior recorded in cetaceans, point to the existence of lateralized use of the flippers at the population level in harbor porpoises and possibly other cetacean species. [source] Reconstruction of large posttraumatic skeletal defects of the forearm by vascularized free fibular graft,MICROSURGERY, Issue 6 2004Roberto Adani M.D. Vascularized bone graft is most commonly applied for reconstruction of the lower extremity; indications for its use in the reconstruction of the upper extremity have expanded in recent years. Between 1993,2000, 12 patients with segmental bone defects following forearm trauma were managed with vascularized fibular grafts: 6 males and 6 females, aged 39 years on average (range, 16,65 years). The reconstructed site was the radius in 8 patients and the ulna in 4. The length of bone defect ranged from 6,13 cm. In 4 cases, the fibular graft was harvested and used as a vascularized fibula osteoseptocutaneous flap. To achieve fixation of the grafted fibula, plates were used in 10 cases, and screws and Kirschner wires in 2. In the latter 2 cases, an external skeletal fixator was applied to ensure immobilization of the extremity. The follow-up period ranged from 10,93 months. Eleven grafts were successful. The mean period to obtain radiographic bone union was 4.8 months (range, 2.5,8 months). Fibular grafts allow the use of a segment of diaphyseal bone which is structurally similar to the radius and ulna and of sufficient length to reconstruct most skeletal defects of the forearm. The vascularized fibular graft is indicated in patients with intractable nonunions where conventional bone grafting has failed or large bone defects, exceeding 6 cm, are observed in the radius or ulna. © 2004 Wiley-Liss, Inc. Microsurgery 24:423,429, 2004. [source] Absent ductus venosus associated with skeletal anomalies of the ulna and radiusPRENATAL DIAGNOSIS, Issue 1 2010Graziano Clerici No abstract is available for this article. [source] Fetal size charts for the Italian population.PRENATAL DIAGNOSIS, Issue 6 2005Normative curves of head, abdomen, long bones Abstract Objective To describe size charts developed from fetuses of Italian couples. Method Prospective cross-sectional investigation conducted in three referral centers for prenatal diagnosis. The population of the study included fetuses between the 16th and the 40th week of gestation recruited prospectively and examined only once for the purpose of this study. Exclusion criteria comprised all maternal and/or fetal conditions possibly affecting fetal biometry. The following biometric variables were measured: biparietal diameter, head circumference, abdominal circumference, femur, tibia, humerus, ulna and radio length. The statistical procedure recommended for analyzing this type of data set was employed to derive normal ranges and percentiles. Birthweight was also recorded. Our centiles were then compared with results from other studies. Results The best-fitted regression model to describe the relationships between head circumference and abdominal circumference and gestational age was a cubic one, whereas a simple quadratic model fitted BPD, and length of long bones. Models fitting the SD were straight lines or quadratic curves. Neither the use of fractional polynomials (the greatest power of the polynomials being 3) nor the logarithmic transformation improved the fitting of the curves. Conclusion We have established size charts for fetuses from Italian couples using the recommended statistical approach. Since the mean birthweight in this study is not statistically different from the official birthweight reported for the Italian population, these reference intervals, developed according to the currently approved statistical methodology, can be employed during second- and third-trimester obstetric ultrasound of fetuses from Italian couples. Copyright © 2005 John Wiley & Sons, Ltd. [source] Functional anatomy of the olecranon process in hominoids and plio-pleistocene homininsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2004Michelle S.M. Drapeau Abstract This study examines the functional morphology of the olecranon process in hominoids and fossil hominins. The length of the bony lever of the triceps brachii muscle (TBM) is measured as the distance between the trochlear articular center and the most distant insertion site of the TBM, and olecranon orientation is measured as the angle that this bony lever makes with the long axis of the ulna. Results show that Homo, Pan, Gorilla, most monkeys, and the Australopithecus fossils studied have similar relative olecranon lengths. Suspensory hominoids and Ateles have shorter olecranons, suggesting, in some instances, selection for greater speed in extension. The orientation that the lever arm of the TBM makes with the long axis of the ulna varies with preferred locomotor mode. Terrestrial primates have olecranons that are more posteriorly oriented as body size increases, fitting general models of terrestrial mammalian posture. Arboreal quadrupeds have more proximally oriented lever arms than any terrestrial quadrupeds, which suggests use of the TBM with the elbow in a more flexed position. Olecranon orientation is not consistent in suspensory hominoids, although they are all characterized by orientations that are either similar or more posterior than those observed in quadrupeds. Homo and the fossils have olecranons that are clearly more proximally oriented than expected for a quadruped of their size. This suggests that Homo and Australopithecus used their TBM in a flexed position, a position most consistent with manipulatory activities. Am J Phys Anthropol, 2003. © 2003 Wiley-Liss, Inc. [source] Biomechanics of the Fractured Medial Coronoid Process and the Isolated Anconeal Process in the Canine Elbow JointANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005J. Maierl Introduction:, Elbow dysplasia is one of the most important orthopaedic diseases of the canine elbow joint. The medial coronoid process (MCP) and the anconeal process (AP) are involved with a high incidence. Aims:, The aim of this study was to clarify whether these processes are especially loaded resulting in osteoarthrosis. Material and Methods:, Elbow joints were examined from dogs of various breeds, with a body weight over 20 kg and an age ranging from 1 to 12 years. Only joints without damage to the articular cartilage have been included in this investigation. Articular surfaces have been evaluated macroscopically, subchondral bone density (long-term loading) and split-lines (long-term tensile loading) have been determined. Results:, In the humeral fossa olecrani, there was a distinct impression on the inner side of the lateral compared to the medial epicondyle. In the ulna, the MCP was much greater than the lateral coronoid indicating that the medial process has to support the humeral condyle to a higher extent. Subchondral split lines with a transverse orientation in the fossa olecrani gave evidence of long-term transverse tensile loading in this area. Split lines on the MCP were oriented radially as if the lateral edge was bent downwards. Subchondral bone density in the fossa olecrani was higher towards the lateral epicondyle in comparison to the medial. Furthermore, there was a bone density maximum on the medial part of the humeral condyle opposite of the MCP with its very high density. Discussion:, Gait analyses showed that there is a transverse, medially oriented force of up to 4% bodyweight acting on the paw during midstance. As the carpus is stable when slightly hyperextended during midstance loading there is a long lever arm from the ground up to an assumed rotation centre in the depth of the trochlear notch. The medially directed ground reaction force slightly rotates the forearm inwards causing a bending moment about the elbow joint, which leads to an increased pressure of the AP and the MCP. This bending in addition to sagittal loading is the reason for the high susceptibility of the MCP and AP. [source] A New Non-Pterodactyloid Pterosaur from Qinglong County, Hebei Province of ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2009Junchang LÜ Abstract: A new basal non-pterodactyloid pterosaur, Changchengopterus pani gen. et sp. nov., is erected, on the basis of a nearly complete postcranial skeleton. The new taxon is distinguished by relatively short extensions of the prezygapophyses, postzygapophyses and haemal arches of the caudal vertebrae; a humerus that has a subtriangular deltopectoral crest; limb elements that decrease in length in the following order: ulna> wing-phalange 2 > wing-phalange 3 = wing-phalange 1>humerus >tibia>femur>wing-metacarpal. Phylogenetic analysis suggests that Changchengopterus is a basal member of rhamphorhynchoids, and more closely related to Dorygnathus than to other rhamphorhychoids. The geological age of the Changchengopterus -bearing sediments is no latter than the end of the Late Jurassic and it is possible Middle Jurassic. [source] A Baby Pterodactyloid Pterosaur from the Yixian Formation of Ningcheng, Inner Mongolia, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2009Junchang LÜ Abstract: A new baby pterodactyloid pterosaur with soft tissue preserved, Ningchengopterus liuae gen. et sp. nov., is erected based on a nearly complete skeleton with a skull. It was characterized by the skull, slightly longer than the combined length of the dorsal and sacral vertebrae; 50 teeth (including upper and lower jaws); short mid-cervical vertebrae; the humerus and the scapula, equal to that of the wing metacarpal in length; the ulna and the femur, equal to that of the first and third wing phalanx in length, respectively. The similar ratio of the wing phalanx 2 to wing phalanx 1 of Ningchengopterus and Eosipterus implies that Ningchengopterus may be close to the ctenochasmatid pterosaur. However, it may also imply that the isometrically growing of the first two wing phalanges exists among some pterosaurs. [source] The concomitant occurrence of multiple epidermal cysts, osteomas and thyroid gland nodules is not diagnostic for Gardner syndrome in the absence of intestinal polyposis: a clinical and genetic reportBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2003S.-M. Herrmann Summary Gardner syndrome, a phenotypic variant of familial adenomatous polyposis, is characterized by the classical clinical triad of skin and soft tissue tumours, osteomas and intestinal polyposis, but disease patterns with pairs of these findings have also been reported. Different mutations in the adenomatous polyposis coli (APC) gene have been shown to be associated with Gardner syndrome disease phenotypes. A 36-year-old patient presented with multiple epidermal cysts on the face, left ear lobe and neck, and the possible diagnosis of Gardner syndrome was based on the additional findings of two classical osteomas in the left radius and ulna and a cold non-malignant nodule of the thyroid gland. Intestinal polyposis was lacking at the time of examination. Major deletions but not microdeletions were excluded by a cytogenetic analysis with 650 chromosomal bands per haploid set. Systematic sequencing of the entire coding region of the APC gene (> 8500 bp) of the patient and five healthy controls was also performed. As a results, new APC gene polymorphisms were identified in exons 13 [A545A (A/G)] and 15 [G1678G (A/G), S1756S (G/T), P1960P (A/G)]. We also detected D1822V (A/T) which has recently been reported to be potentially related to colorectal carcinoma, and genotyped 194 randomly chosen healthy individuals from the Glasgow area for this as well as for the above variants in exons 13 and 15. Interestingly, of the 194 controls, 112 carried the DD (57·7%), 71 the DV (36·6%), and the remaining 11 (5·7%), including our patient, the VV genotype. It is therefore unlikely that APC D1822V serves as an important marker for colorectal carcinoma. In conclusion, we failed to identify obvious germline candidate mutations in >,8500 bp of the coding region of the APC gene in a patient with multiple epidermal cysts, osteomas and a thyroid gland nodule; major chromosomal deletions were excluded. Therefore, we assume that only the presence of intestinal polyposis is a marker for Gardner syndrome. [source] | ||||||||||||||||||||||||||||