Question

What is Os Odontoideum, and what characterizes it in terms of the normally developed cephalic part of the dens not fusing with the C2 body and the presence of a smooth, wide lucent defect between the body of C2 and dens?

Answer 1

Os Odontoideum is a rare anomaly in which the cephalic part of the dens in the second cervical (C2) vertebra does not fuse with the C2 body, leading to a distinctive defect between the body of C2 and the dens.

Step-by-step explanation:

Os Odontoideum is a rare developmental anomaly that involves the second cervical (C2) vertebra, also known as the axis. In a normally developed C2 vertebra, the cephalic part of the dens fuses with the C2 body, creating a stable joint. However, in cases of Os Odontoideum, the cephalic part of the dens does not fuse with the C2 body, resulting in a smooth, wide lucent defect between the body of C2 and the dens.