Dens of the second vertebra.
A third attachment of the second vertebra to the first must now be added
to our account; this is effected with the first vertebra by the dens (g and n
in figure 5, h, i, k, l, n in figure 6, G in figure 10 and 11) of the second
vertebra of the neck.
Between the two
[processus articularis superior] of
the second vertebra, from the upper and middle region of its body, grows a
certain conspicuous, tall process, quite hard and solid, which because it
resembles a tooth — particularly a human canine tooth — the Greeks called
and o)dou/j; Hippocrates called the second
vertebra by this name,
but not the first (as Julius Pollux
ignorant of dissections, wrongly count it). Still others have named this
process from its resemblance to a spinning top or pinecone kwnoeidh=;
others, because it swells like a
spear-point or pyramid pu/rinon or purinoeidh=.
This process enters the cavity of the first vertebra (K and L
in figure 3) which we have written is located where the body
[arcus anterior atlantis] of the
first vertebra should be, and where we have written is carved the depression
[fovea dentis] which is lined with
cartilage and receives the anterior part
[facies articularis anterior] of the
dens that projects slightly with a smooth and slippery bulge (g in figure 5).
The back of the dens, placed opposite this swelling, bulges out more and is
thicker than where it first comes out of the second vertebra. For here the dens
makes a single depression on each side (k and l in figure 5 and 6) and a third
on the posterior side (i in figure 6).
Though this figure belongs to the second book, I have placed it here because it is no small aid to understanding what is said here. The first neck vertebra is marked A, B, C. The second is D and D. G is the body of the second, H the dens, I the smooth ligament [apical ligament of the dens] inserted from the dens to the occipital bone. K is the transverse ligament securing the dens to the first vertebra.