title: Synchrotron imaging reveals bone healing and remodelling strategies in extinct and extant vertebrates.
abstract: Current understanding of bone healing and remodelling strategies in vertebrates has traditionally relied on morphological observations through the histological analysis of thin sections. However, chemical analysis may also be used in such interpretations, as different elements are known to be absorbed and used by bone for different physiological purposes such as growth and healing. These chemical signatures are beyond the detection limit of most laboratory-based analytical techniques (e.g. scanning electron microscopy). However, synchrotron rapid scanning-X-ray fluorescence (SRS-XRF) is an elemental mapping technique that uniquely combines high sensitivity (ppm), excellent sample resolution (20-100 µm) and the ability to scan large specimens (decimetre scale) approximately 3000 times faster than other mapping techniques. Here, we use SRS-XRF combined with microfocus elemental mapping (2-20 µm) to determine the distribution and concentration of trace elements within pathological and normal bone of both extant and extinct archosaurs (Cathartes aura and Allosaurus fragilis). Results reveal discrete chemical inventories within different bone tissue types and preservation modes. Chemical inventories also revealed detail of histological features not observable in thin section, including fine structures within the interface between pathological and normal bone as well as woven texture within pathological tissue.
authors.affiliation: School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Williamson Building, Oxford Road, , Manchester M13 9PL, UK.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Anné
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: Edwards
authors.forename: Roy A
authors.initials: RA
authors.lastname: Wogelius
authors.forename: Allison R
authors.initials: AR
authors.lastname: Tumarkin-Deratzian
authors.forename: William I
authors.initials: WI
authors.lastname: Sellers
authors.forename: Arjen
authors.initials: A
authors.lastname: van Veelen
authors.forename: Uwe
authors.initials: U
authors.lastname: Bergmann
authors.forename: Dimosthenis
authors.initials: D
authors.lastname: Sokaras
authors.forename: Roberto
authors.initials: R
authors.lastname: Alonso-Mori
authors.forename: Konstantin
authors.initials: K
authors.lastname: Ignatyev
authors.forename: Victoria M
authors.initials: VM
authors.lastname: Egerton
authors.forename: Phillip L
authors.initials: PL
authors.lastname: Manning
mesh_terms: D000818:Animals; D001717:Birds / Q000033:anatomy & histology*; D016723:Bone Remodeling; D001842:Bone and Bones / Q000033:anatomy & histology / Q000473:pathology / Q000502:physiology; D025061:Dinosaurs / Q000033:anatomy & histology; D005580:Fossils / Q000033:anatomy & histology; D017102:Fracture Healing; D017356:Synchrotrons
keywords: SRS–XRF; archosaur; bone; fracture healing; histology