The Dinosaurs of Wyoming - Wyoming State Geological Survey ...

54 THE DINOSAURS OF 'WYOMING
Microscopical study (Figures 15, 17) shows the presence
of scattered lacunae, once occupied by the bone cells; spindleshaped
bodies with short canaliculi. A section of bone taken
from the very middle of the tumor shows more compact bony
structure than exists at the periphery (Figure 17).
Other accidents to the enormously elongated tail of the
amphibious (sauropod) dinosaurs are known, and have been
described by Hatcher, Holland and Osborn (Figures 9, 10,
12 c, 13 a, b, d). These injuries indicate that the tail was
either dragged over rough ground, was used as a flail, or was
used in swimming, or perhaps all three. One type of pathological
change often seen in the tail of the sauropod dinosaurs
was a thickening, or ossification of the longitudinal ligaments,
producing a condition called Spondylitis deformans, which is a
very ancient diseased condition, known from early Mesozoic
times, and extremely common at the present time.
An infected injury is seen in the tail of a large dinosaur
mounted in the Carnegie Museum at Pittsburgh.
Lesions similar to those associated with rheumatism are
known in the dinosaurs, and some of them had tooth troubles.
A large dinosaur skeleton, mounted in the United States
Tational Museum (Figures 24, 40, a), shows in one hip a huge
bone abscess, due doubtless to a bone injury.
A large hook-like exostosis, following an infection, is seen
on the inner face of a shoulder-blade of a three-horned dinosaur
(Figure 40). The pathological growth was partly covered
by muscle, but it may have rubbed against the ribs.
Pathological outgrowths exactly like this are often seen on
modern human bones.
All together there is a known array of fifteen different
types of pathological processes found among Mesozoic reptiles.
Some of these conditions are called arthritides, multiple
arthritis, arthritis deformans, tumors of two types, necrosis,
hyperostoses and various kinds of fractures and slight injuries.