What is L5 - S1 located?

Answer 1

They are the names of specific vertebrae in the spine. The anatomy of the spine is sectioned for better identification and specificity. There is the neck area, the cervical spine; the main upper part of the back is the thoracic spine; the area at the "small of the back" is the lumbar spine; the part below that is the Sacral spine (also called the sacrum) which is five fused together vertebrae; and then finally the tailbone is called the coccyx and is actually four fused vertebrae.

Each of the vertebra in a section is numbered. There are normally 33 vertebrae in humans (counting the fused ones). There are 7 in the cervical area, 12 in the thoracic area, 5 in the lumbar area, and the 9 making up the sacrum and coccyx.

So L5 is the fifth Lumbar vertebra (counting from the top down). It is also the most common vertebra involved in lumbar disorders and low Back pain. It is the last of the lumbar vertebrae. L4 is in the general area of the waist or at the highest point of the pelvic bones. So just down from there is L5 and S1 is the next one down.