A disc becomes herniated when you tear the annulus, the basket-weave-type supporting structure of the disc, by twisting. This weakens the structure and makes it work abnormally. A herniation is ...

A posterior annular tear is a painful condition characterized by tear or rupture in the annulus fibrosus (outer layer of an intervertebral disc, particularly in the posterior (back) region of the ...

Thus, a left L5-S1 disc herniation compresses the left S1 nerve root. The nucleus pulposus is posterior in the annulus and the posterior longitudinal ligament (PLL) is midline, creating a somewhat ...