L5-S1 is the exact spot where the lumbar spine ends and the sacral spine begins. The lumbosacral joint connects these bones.

You may have heard your practitioner mention something about your L4-L5 spinal segment. The lower back (lumbar spine) is a ...

Objectives: To observe the prevalence of lumbar intervertebral disc degeneration in elite athletes as compared with published literature of changes seen in non-athletes—that is, normal population.