First Documented Pathologies in Tenontosaurus tilletti with Comments on Infection in Non-Avian Dinosaurs

Abstract

In 2001, a nearly complete sub-adult Tenontosaurus tilletti was collected from the Antlers Formation (Aptian-Albian) of southeastern Oklahoma. Beyond its exceptional preservation, computed tomography (CT) and physical examination revealed this specimen has five pathological elements with four of the pathologies a result of trauma. Left pedal phalanx I-1 and left dorsal rib 10 are both fractured with extensive callus formation in the later stages of healing. Left dorsal rib 7 (L7) and right dorsal rib 10 (R10) exhibit impacted fractures compressed 26 mm and 24 mm, respectively. The fracture morphologies in L7 and R10 indicate this animal suffered a strong compressive force coincident with the long axis of the ribs. All three rib pathologies and the pathological left phalanx I-1 are consistent with injuries sustained in a fall. However, it is clear from the healing exhibited by these fractures that this individual survived the fall. In addition to traumatic fractures, left dorsal rib 10 and possibly left phalanx I-1 have a morphology consistent with post-traumatic infection in the form of osteomyelitis. The CT scans of left metacarpal IV revealed the presence of an abscess within the medullary cavity consistent with a subacute form of hematogenous osteomyelitis termed a Brodie abscess. This is only the second reported Brodie abscess in non-avian dinosaurs and the first documented occurrence in herbivorous dinosaurs. The presence of a Brodie abscess, known only in mammalian pathological literature, suggest mammalian descriptors for bone infection may be applicable to non-avian dinosaurs.

A limping dinosaur in the Late Jurassic: Pathologies in the pes of the neornithischianOthnielosaurus consorsfrom the Morrison Formation (Upper Jurassic, USA)

“…On the other hand, the impact fractures located in the phalanges III-1 and IV-4, which supported the weight of Othnielosaurus on the ground, might had causing chronic pain and, consequently, a limp. Similar cases of pedal pathologies affecting an individual's mobility have been described in the fossil record of dinosaurs, crocodyliforms and mammals, including hominoids (Hanna 2002;Farke and O'Connor 2007;Cabral et al 2011;Anné et al 2014;Foth et al 2015;McCrea et al 2015;Macdonald and Currie 2018;Hunt et al 2019). Survival of lesions of weight-bearing bone would have greater consequence for obligate bipeds and evidence of lesions healing in these bones is rare (Hearn and Williams 2019).…”

Case study of radial fibrolamellar bone tissues in the outer cortex of basal sauropods

“…[7]). Bracketing sauropods by reptilian and bird cases is the best option if comparative data are available, as the response of mammals and reptiles to the same pathology can significantly differ [43,46]. Nevertheless, palaeopathology needs to encompass fossil and medical literature to produce the most informative results.…”

“…However, a pedal phalanx of an individual of Tyrannosaurus rex described by Vittore & Henderson [65] matches the Brodie abscess differential diagnosis based on radiographic and computed tomography (CT) data (sclerotic bone reaction, involucrum and sequestra set-up and pus cavity development). Recently, Hunt et al [46] described some pathological bones of Tenontosaurus tilletti, including Brodie abscess in a metacarp. Even though Brodie abscess-like infection occurs within dinosaurs, no histological observation supports this pathology in the samples we studied here.…”

Description and etiology of paleopathological lesions in the type specimen of Parasaurolophus walkeri (Dinosauria: Hadrosauridae), with proposed reconstructions of the nuchal ligament

“…The identified lesions were compared with another specimen, referred to as cf. Parasaurolophus (TMP 1992.053.0021), as well as those included in the increasing database of fossilized injuries and diseases of dinosaurs and other extinct vertebrates (e.g., Bertozzo et al in prep; Barbosa et al, 2016, 2018; Molnar, 2001; Tanke & Rothschild, 2002, 2014; Senter & Juengst, 2016; Hunt et al, 2019). To facilitate description of the presence of the nuchal ligament in P .…”

“…The identified lesions were compared with another specimen, referred to as cf. Parasaurolophus (TMP 1992.053.0021), as well as those included in the increasing database of fossilized injuries and diseases of dinosaurs and other extinct vertebrates (e.g., Bertozzo et al in prep;Barbosa et al, 2016Barbosa et al, , 2018Molnar, 2001;Tanke & Rothschild, 2002Senter & Juengst, 2016;Hunt et al, 2019). To facilitate description of the presence of the nuchal ligament in P.walkeri, and its connection to the purported pathological neural spines, the origins, insertions, and structure of the nuchal ligament were created based on reconstructions for extant crocodiles and birds (Tsuihiji, 2004;Yasuda, 2002), sauropods (Woodruff, 2017), and mammals (Bertram & Gellman, 2002;Fielding et al, 1976;Kadri & Al-Mefty, 2007;May-Davis & Kleine, 2014).…”