Mögliches Potential der digitalen Volumentomographie zum Nachweis von Calcaneusfrakturen

Cone beam computed tomography is a state-of-the-art imaging tool, initially developed for dental and maxillofacial application. With its high resolution and low radiation dose, cone beam tomography has been expanding its application fields, for example, to diagnosis of traumata and fractures in the head and neck area. In this study, we demonstrate superior and satisfactory performance of cone beam tomography for the imaging of a calcaneus fracture in comparison to conventional X-ray and computed tomography.Die digitale Volumentomographie ist ein etabliertes Verfahren in der Zahnheilkunde und Mund- Kiefer- und Gesichtschirurgie. Aufgrund der hohen Bildqualität sowie einer hohen Ortsauflösung wird diese Technik mittlerweile ebenfalls in der Traumadiagnostik und im Bereich des Gesichtsschädels erfolgreich eingesetzt. Das Ziel der Arbeit ist eine vergleichende Darstellung zwischen konventioneller Röntgendiagnostik, der Computertomographie und der digitalen Volumentomographie am Beispiel der Beurteilung einer Calcaneusfraktur

Mice over-expressing salmon calcitonin have strongly attenuated osteoarthritic histopathological changes after destabilization of the medial meniscus

SummaryObjectiveCalcitonin is well-known for its inhibitory actions on bone-resorbing osteoclasts and recently potential beneficial effects on cartilage were shown. We investigated effects of salmon calcitonin (sCT) on the articular cartilage and bone, after destabilization of the medial meniscus (DMM) in normal and sCT over-expressing mice.DesignBone phenotype of transgenic (TG) C57Bl/6 mice over-expressing sCT at 6months and 12months was investigated by (1) serum osteocalcin and urinary deoxypyridinoline and (2) dynamic and normal histomorphometry of vertebrae bodies. In subsequent evaluation of cartilage and subchondral bone changes, 44 10-week old TG or wild-type (WT) mice were randomized into four groups and subjected to DMM or sham-operations. After 7weeks animals were sacrificed, and knee joints were isolated for histological analysis.ResultsTrabecular bone volume (BV/TV) increased 150% after 6months and 300% after 12months in sCT-expressing mice when compared to WT controls (P<0.05). Osteoblast number, bone formation rate and osteocalcin measurements were not affected in TG mice over-expressing sCT. In WT animals, a 5-fold increase in the quantitative erosion index was observed after DMM, and the semi-quantitative OARSI score showed over 400% (P<0.001) increase, compared to sham-operated WT mice. DMM-operated TG mice were protected against cartilage erosion and showed a 65% and 64% (P<0.001) reduction, respectively, for the two histopathological evaluation methods.ConclusionssCT over-expressing mice had higher bone volume, and were protected against cartilage erosion. These data suggest that increased levels of sCT may hamper the pathogenesis of osteoarthritis (OA). However more studies are necessary to confirm these preliminary results