[p. 228]shortened,
and the atrophy of the flesh occurs, for the most part, on the side
opposite to the dislocation. In an adult the bones remain of their
natural size.
Part 29
Dislocation at the joint of a finger is easily recognized. Reduction
is to be effected by making extension in a straight line, and applying
pressure on the projecting bone, and counter-pressure on the opposite
side of the other. The treatment is with bandages. When not reduced,
callus is formed outside of the joint. When the dislocation takes
place at birth, during adolescence the bones below the dislocation
are shortened, and the flesh is wasted rather on the opposite than
on the same side with the dislocation. When it occurs in an adult
the bones remain of their proper size.
Part 30
The jaw-bone, in few cases, is completely dislocated, for the zygomatic
process formed from the upper jaw-bone (malar?) and the bone behind
the ear (temporal?) shuts up the heads of the under jaw, being above
the one (condyloid process?), and below the other (coronoid process?).
Of these extremities of the lower jaw, the one, from its length, is
not much exposed to accidents, while the other, the coronoid, is more
prominent than the zygoma, and from both these heads nervous tendons
arise, with which the muscles called temporal and masseter are connected;
they have got these names from their actions and connections; for
in eating, speaking, and the other functional uses of the mouth, the
upper jaw is at rest, as being connected with the head by synarthrosis,
and not by diarthrosis (enarthrosis?): but the lower jaw has motion,
for it is connected with the upper jaw and the head by enarthrosis.
Wherefore, in convulsions and tetanus, the first symptom manifested
is rigidity of the lower jaw; and the reason why wounds in the temporal
region are fatal and induce coma, will be stated in another place.
These are the reasons why complete dislocation does not readily take
place, and this is another reason, because there is seldom a necessity
for swallowing so large pieces of food as would make a man gape more
than he easily can, and dislocation could not take place in any other
position than in great gaping, by which the jaw is displaced to either
side. This circumstance, however, contributes