Other nasopharyngeal cysts include more lateral benign seromucinous retention cysts (Fig. 10), pharyngeal bursae of Luschka (between the longus colli muscle heads) and oncocytic cysts (Warthin's tumor, not reported in children).
Herniated Nucleus Pulposus. Definition. A herniated disc is a fragment of the disc nucleus which is pushed out of the outer disc margin, into the spinal canal through a tear or rupture.. In the herniated disc's new position, it presses on spinal nerves, producing pain down the accompanying leg. This produces a sharp, severe pain down the entire leg and into the foot.
Disc Extrusion. Disc Extrusion. What is a Disc Extrusion â Definition. An extrusion, also known as herniated disc, is a spinal condition that can lead to pain and increase the risk of further injury to the spine, and it can cause arthritis and other conditions. Both injury and aging can trigger this type of back condition.