“Calcification ventral to the dens” means that there is calcification (calcium deposition) in the area right in front of the C2 vertebra. The dens belongs to the C2 vertebra and the C1 vertebra arch is right in front of C2. This area of calcification could be between the C1 ring and the C2 dens or in front of the C1 ring but inadvertantly called “in front of the dens”.
Calcification can occur from injury, inflammation, infection or simple “wear and tear”. I cannot tell you the significance of this calcification but more likely than not, it is not causing your lower neck pain or arm pain.
The CT scan is reliable to look for foraminal stenosis (see website for description) but does not demonstrate as well the presence of a disc herniation. An MRI would be a much better imaging test for herniations.
Dr. Corenman