ieve it was in the majority of cases
the result of irregular impact on the part of the projectile. In support
of this view it may be added that such injuries were most common in the
bones of the tarsus, bones especially liable to be struck by ricochet
bullets.
It was generally believed that bullets travelling at a very high degree
of velocity were liable to cause severe comminution of the short bones,
but I never saw any cases supporting this opinion; in point of fact, all
the short-range lesions of this nature that I saw were of the clean
perforating variety. I believe that this is capable of satisfactory
explanation on the ground of the thin character of the layer of compact
tissue which for the most part ensheaths the short bones; this decreases
the resistance offered to the bullet and so tends to localise the
lesion. This statement may be supported by two observations with regard
to the long and flat bones. First, if the shaft of a long bone be hit
above the junction of diaphysis and epiphysis, the cancellous tissue in
and extending from the medullary cavity is pulverised, and examination
of fragments from such fractures gives the impression of the inner
aspect having been scraped clean. Secondly, I saw one fracture of the
ilium produced by a bullet taking a course between its compact layers
for 3 inches from the notch between the anterior superior and anterior
inferior spines; the bone to the extent of 2-1/2 square inches was
pulverised, the cancellous tissue blown away as dust, and the compact
tissue only represented by scales still adhering by their periosteum to
the muscles attached to the two surfaces of the bone. This injury was
produced from a rifle fired at five yards distance, and was an extreme
example; but, on the other hand, it illustrates only what we are
thoroughly well acquainted with in the case of flat bones, such as those
of the cranium, where the compact element is abundant in comparison with
the cancellous, and the resistance offered to the bullet is consequently
great.
Some remarks on transverse fractures of the patella will be found under
the heading devoted to that bone.
Lesions of the flat bones are considered at some length in Chapter VII.,
which deals with injuries to the head, and their special features are
there described; some further remarks on these injuries will be found
under the headings of the individual bones.
_Special characters of the symptoms observed, and of the course
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