of the tibia, and the importance of the
overhanging prominent margins in the production of somewhat irregular
injuries (p. 170). Putting these peculiarities on one side, the
cancellous ends are subject to the type forms of injury; thus
perforations either of the head of the bone or the malleolus were common
injuries. The fractures of the shaft also deviated from the type in so
far as the broad flat surfaces in the upper two thirds of the bone
rendered it especially liable to the results of lateral impact, and to
the production of the extreme wedge-shaped types of fracture. Plate
XXII. illustrates the different result of a bullet striking the dense
and strong spine at a low rate of velocity, a notch only resulting. If,
on the other hand, the lateral surfaces were struck, a wedge with the
base corresponding to the posterior surface was the most common injury,
the spine in many cases remaining intact and maintaining the continuity
of the bone. Wedge-shaped fractures of this bone were apt to show
multiple secondary wave fissures concentric with the main line, and
consequently free comminution. I saw several examples, the loose
fragments being remarkably numerous. Plate XIX. is an example of an
oblique fracture produced by a bullet which has ploughed across the
bone, displacing large fragments anteriorly, but finely comminuting the
bone in its course, and leaving small fragments of the mantle on its
way. Plate XX. is an example of the rare condition of transverse
fracture.
[Illustration: PLATE XXIII
Skiagram by H. CATLING.
Engraved and Printed by Bale and Danielsson, Ltd.
(41) SPURIOUS PERFORATION OF THE FIBULA
Moderate range, 'about 1,000 yards.'
The injury was caused by an 8 mm. bullet, which entered base foremost
and lodged in the calf. The fracture is really an incomplete stellate
form, two well-marked transverse fissures extending from the point
struck. The position of the bullet suggests its entry into the limb base
foremost, and as it is retained low velocity may be assumed.]
This fracture was produced by a bullet travelling at a high rate of
velocity, which struck the posterior surface of the tibia, and caused a
grooving, accompanied by a horizontal fissure through the whole
thickness of the bone; later it struck the fibula more directly, and
produced an ordinary comminuted fracture two inches above the malleolus.
Perforations of the shaft were far more common than in the case of the
femur, and I saw
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