Two types of bone necrosis in the Middle TriassicPistosaurus longaevusbones: the results of integrated studies

Abstract

Avascular necrosis, diagnosed on the basis of either a specific pathological modification of the articular surfaces of bone or its radiologic appearance in vertebral centra, has been recognized in many Mesozoic marine reptiles as well as in present-day marine mammals. Its presence in the zoological and paleontologic record is usually associated with decompression syndrome, a disease that affects secondarily aquatic vertebrates that could dive. Bone necrosis can also be caused by infectious processes, but it differs in appearance from decompression syndrome-associated aseptic necrosis. Herein, we report evidence of septic necrosis in the proximal articular surface of the femur of a marine reptile, Pistosaurus longaevus, from the Middle Triassic of Poland and Germany. This is the oldest recognition of septic necrosis associated with septic arthritis in the fossil record so far, and the mineralogical composition of pathologically altered bone is described herein in detail. The occurrence of septic necrosis is contrasted with decompression syndrome-associated avascular necrosis, also described in Pistosaurus longaevus bone from Middle Triassic of Germany.

Hematological convergence between Mesozoic marine reptiles (Sauropterygia) and extant aquatic amniotes elucidates diving adaptations in plesiosaurs

“…This indicates a more sophisticated diving profile in the former group. In accordance with this, avascular necrosis has repeatedly been reported for pistosauroids throughout their evolutionary history (Rothschild & Storrs, 2003; Surmik et al, 2017). In extant tetrapods, this type of bone tissue lesion is indicative of decompression syndrome (Carlsen, 2017).…”

Tuberculosis-like respiratory infection in 245-million-year-old marine reptile suggested by bone pathologies

“…They include post-traumatic malformation [ 5 , 6 ], congenital defects [ 7 , 8 ] and neoplasms [ 3 , 9 – 11 ]. Previous reports of Mesozoic marine reptile pathology have been limited to recognition of bone necrosis, of both aseptic [ 12 ] and infectious [ 13 ] aetiology. Aseptic avascular necrosis associated with decompression syndrome is quite common in ancient marine reptiles, including sea turtles [ 14 , 15 ], mosasaurs [ 16 ], ichthyosaurs [ 12 ] and sauropterygians [ 12 , 17 ].…”

“…Aseptic avascular necrosis associated with decompression syndrome is quite common in ancient marine reptiles, including sea turtles [ 14 , 15 ], mosasaurs [ 16 ], ichthyosaurs [ 12 ] and sauropterygians [ 12 , 17 ]. The fossil record of infectious disease in marine reptiles is scarce, limited to bacterial infections in Triassic sauropterygians [ 13 ] and Cretaceous mosasaurs [ 18 , 19 ]. Fossilization of actual microorganisms is exceptionally rare (e.g.…”

Peer Review #1 of "Hematological convergence between Mesozoic marine reptiles (Sauropterygia) and extant aquatic amniotes elucidates diving adaptations in plesiosaurs (v0.1)"

“…Therefore, its evolution coincided not only with the emergence of elevated metabolic rates but also changes in sensory ecology, locomotion, and diving profiles compared to pachypleurosaurids and nothosaurids (Sues, 1987;Neenan et al, 2017;Surmik et al, 2017). All of these traits prepared the emergence of the Plesiosauria in the Late Triassic.…”

“…Manuscript to be reviewed evolutionary history (Rothschild & Storrs, 2003;Surmik et al, 2017). In extant tetrapods, this type of bone tissue lesion is indicative of decompression syndrome (Carlsen, 2017).…”