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Right Radius (right + radius)
Selected AbstractsFore 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] Prenatal identification of isolated bilateral radial dysplasiaJOURNAL OF CLINICAL ULTRASOUND, Issue 3 2009Alfredo Mancuso Abstract Radial aplasia or hypoplasia is characterized by complete or partial absence of the radius and/or radial ray structure occurring in 1:30,000 live births. It may be unilateral or bilateral of varying severity, and may be isolated or associated with other anomalies. We report an unusual case of isolated radial aplasia at 20 weeks' gestation with complete absence of the right radius and thumb associated with marked hypoplasia of the left radius. The intrauterine 2- and 3-dimensional findings, postnatal radiographic evaluation, and autopsy results are reported. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009 [source] Repair of rabbit segmental defects with the thrombin peptide, TP508JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2004Michael R. Sheller Abstract The synthetic peptide, TP508 (Chrysalin®), was delivered to rabbit segmental bone defects in biodegradable controlled-release PLGA microspheres to determine its potential efficacy for enhancing healing of non-critically and critically sized segmental defects. Non-critically sized radial defects were created in the forelimbs of New Zealand White rabbits, which were randomized into three treatment groups receiving 10, 50 and 100 ,g doses of TP508 in the right radius and control microspheres (without TP508) in the left radius. Torsional testing of the radii at six weeks showed a significant increase in ultimate torque, failure torque, ultimate energy, failure energy, and stiffness when treated with TP508 compared to controls (p < 0.01 for all measures). Thus, TP508 appeared to enhance or accelerate bone growth in these defects. In a second set of experiments, critically sized ulnar defects were created in the forelimbs of New Zealand White rabbits, which were randomized into two groups with each rabbit receiving microspheres with 100 or 200 ,g of TP508 into the right ulnar defect and control microspheres (without TP508) alone into the left ulnar defect. Bone healing was evaluated with plain radiographs, synchrotron-based microtomography, and mechanical testing. Radiographs of the rabbit limbs scored by three blinded, independent reviewers demonstrated a significantly higher degree of healing when treated with TP508 than their untreated control limbs (p < 0.05). Three-dimensional synchrotron tomography of a limited number of samples showed that the new bone in TP508-treated samples had a less porous surface appearance and open marrow spaces, suggesting progression of bone remodeling. Torsional testing of the ulnae at nine weeks showed a significant increase in maximum torque and failure energy when treated with TP508 compared to controls (p < 0.01 for both measures). These results suggest that TP508 in a controlled release delivery vehicle has the potential to enhance healing of segmental defects in both critically and non-critically sized defects. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Effects of a Mechanical Barrier on the Integration of Cortical Onlay Bone Grafts Placed Simultaneously with Endosseous ImplantCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2002Luiz Z. Salata DDS ABSTRACT Background: Previous experimental studies on onlay bone graft integration have shown either advantages or disadvantages to the use of mechanical barriers. This indicates that the role played by the biologic properties of transplanted bone and membrane in graft revascularization and bone remodeling has not yet been established. The outcomes regarding osseointegration of titanium dental implants applied in such a condition are still contradictory. Purpose: The rabbit's radius model that is grafted onto the mandibular lower border and covered by membrane can reproduce a challenging experimental situation to preliminarily study the factors involved in osseointegration under deprived blood vessels source. Materials and Methods: Fourteen New Zealand White rabbits had a 2.5-cm segment of the right radius osteoectomized and fixed onto the right mandibular lower border using titanium screws. Two screw-shaped titanium implants (2.5 mm wide 2.5 mm long) were installed 7 mm apart in the mid length of the grafted bone. In experimental sites, the graft with the implants and graft-host bone junction were covered by expanded polytetrafluoroethylene (e-PTFE) membrane; control sites were left uncovered. Eight animals from the experimental group and six animals from the control group were sacrificed at 6 and 24 weeks after surgery. Ground sections obtained from en bloc tissues containing graft, implants, and recipient bone were subjected to histologic evaluation and histomorphometric analysis (area occupied by the graft and bone-to-implant contact). Results: The graft showed significantly more resorption after 24 weeks than at 6 weeks (p .05) irrespective of the treatment (with or without membrane), although the amount of new bone was greater at 24 weeks in sites where a membrane was covering the graft. Compared with 6 weeks postoperatively, the bone-to-implant contact was considerably improved at 24 weeks (p .05), and the membrane seemed beneficial for implant osseointegration when compared with unprotected sites (p .05). As a result of graft resorption, the amount of soft tissue was considerably expanded in sites beneath membrane, accompanied by a sustained process of trabecular bone deposition close to the barrier. Conclusions: Cortical onlay grafts covered by membrane demonstrated delayed remodeling, probably as a consequence of a hindered process of graft revascularization. Grafts covered by membrane might rely on previous host bone resorption both to become revascularized and to remodel. The findings that the membrane-protected grafts were most resorbed at 24 weeks might be attributable to better implant osseointegration, because the fixtures were exposed to greater mechanical stimulation in these sites. [source] | |||||||||||||