Relation Between Disc Herniation & Compressed Nerve Root Levels

The video explains why a posterolateral disc herniation at the L4-L5 level compresses the L5 nerve root instead of the L4 nerve root. It covers the anatomy of the vertebral canal, intervertebral regions, and nerve root exit points. The L4 nerve root exits above the herniation level, while the L5 nerve root descends through the L4-L5 space, making it susceptible to compression. The video generalizes this concept to other spinal levels, emphasizing the importance of understanding cauda equina nerve roots within the vertebral canal.

Why does a posterolateral disc herniation at the L4L5 level compress the L5 nerve root instead of the L4 nerve root?

• Because the L5 nerve root exits above the herniation.

• Because the L4 nerve root is protected by the vertebral body.

• Because the L4 nerve root is more lateral.

• Because the L5 nerve root descends through the herniation level.

What is the role of intervertebral foramina in the vertebral column?

• They house the spinal cord.

• They connect the vertebrae to the ribs.

• They allow nerve roots to exit the spinal column.

• They support the vertebral bodies.

Where does the L4 nerve root exit in relation to its associated vertebra?

• At the L3 vertebra.

• Above the L4 vertebra.

• Below the L4 vertebra.

• At the L5 vertebra.

How does the L5 nerve root's path make it susceptible to compression by a herniation at the L4L5 level?

• It is located anterior to the herniation.

• It is protected by the L4 vertebra.

• It descends through the herniation level within the vertebral canal.

• It exits immediately above the herniation.

What general rule can be applied to nerve root compression due to disc herniation?

• The nerve root above the herniation is compressed.

• The nerve root at the level below the herniation is compressed.

• The nerve root two levels below the herniation is compressed.

• The nerve root at the same level as the herniation is compressed.

If a herniation occurs at the L3L4 level, which nerve root is likely to be compressed?

• L5

• L2

• L3

• L4

Why is it important to consider the cauda equina nerve roots within the vertebral canal?

• They determine the height of the vertebrae.

• They influence the curvature of the spine.

• They are crucial for understanding nerve root compression.

• They are responsible for vertebral stability.