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

Area of Science:

• Paleontology
• Vertebrate Paleontology
• Paleopathology

Background:

• A sub-adult Tenontosaurus tilletti specimen was discovered in the Antlers Formation.
• The specimen exhibits exceptional preservation, allowing for detailed analysis.

Purpose of the Study:

• To document and analyze pathological elements in a Tenontosaurus dinosaur.
• To investigate the nature and implications of traumatic injuries and infections in non-avian dinosaurs.

Main Methods:

• Physical examination of the fossil specimen.
• Computed tomography (CT) scanning to analyze bone structure and internal pathologies.
• Comparative analysis with existing paleontological and pathological literature.

Main Results:

• Four of the five pathological elements showed signs of trauma, including fractured ribs (L7, R10) and a pedal phalanx (I-1), indicating survival from a fall.
• Evidence of post-traumatic osteomyelitis was found in left dorsal rib 10 and possibly left phalanx I-1.
• A Brodie abscess, a type of hematogenous osteomyelitis, was identified in the left metacarpal IV, representing the first documented case in a herbivorous dinosaur.

Conclusions:

• The Tenontosaurus individual survived significant traumatic injuries.
• The presence of a Brodie abscess suggests mammalian descriptors for bone infection may apply to non-avian dinosaurs.
• This finding expands our understanding of dinosaur health and disease, particularly in herbivorous species.