Page 43 - My FlipBook

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we shall find that these two lines are so nearly parallel,
that the condyle moves almost directly forwards, in passing
from the cavity to the eminence ; and the parallelism of the
motion is also preserved by the shape of an intermediate car-
tilage.
In this joint there is a moveable cartilage which though
common to both condyle and cavity, ought to be considered
rather as an appendage of the former than of the latter, be-
ing more closely connected with it ; so as to accompany it in
its motion along the common surface of both the cavity and
the eminence. This cartilage is nearly of the same dimen-
sions with the condyle, which it covers ; is hollowed in its in-
ferior surface to receive the condyle ; on its upper surface
it is more unequal, being moulded to the cavity and eminence
of the articulating surface of the temporal bone, though it is
considerably less and is therefore capable of being moved
with the condyle from one part of that surface to another.
Its texture is ligamenta-cartilaginious. This moveable car-
tilage is connected with both the condyle of the jaw, and the
articulating surface of the temporal bone, by distinct liga-
ments, arising from its edges all round. That by which it is
attached to the temporal bone is the most free and loose
;
though both ligaments will allow an easy motion, or sliding
of the cartilage on the respective surfaces of the condyle
and the temporal bone.
These attachments of the cartilage are strengthened, and
the whole articulation secured, by an external ligament,
which is common to both, and which is fixed to the temporal
bone, and to the neck of the condyle. On the inner surface
of the ligament, which attaches the cartilage of the tem-
poral bone, and backwards in the cavity, is placed what is
commonly called the gland of the joint ; at least, the liga-
ment is there much more vascular than at any other part.
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