Introduction to 3-D Lumbar Spine

"Baby, do you understand me now

Sometimes I feel a little mad

But don't you know that no one alive

Can always be an angel

When things go wrong, I seem to be bad

But I'm just a soul whose intentions are good

Oh Lord, please don't let me be misunderstood"

Those are a few of my favorite lines from "Don't let me be misunderstood" originally performed by The Animals.

As we look at the Lumbar Spine, we see that this area of the body is where we can get a lot of pain. It's been said that over 80+% of people will have Low Back Pain (LBP) sometime in their lives. This is an amazing statistic but unfortunately, its a true. What is more interesting is that the Lumbar Spine, because it is the site of pain, is the most misunderstood. We call it the "Noisemaker" because when it's in pain, it can literally make you scream. However, as we look into the Lumbar Spine with Applied Functional Science, we see that the Lumbar Spine is the part of the body who gets beat up on the most and the actual cause may lie somewhere else in the body like at the Hips or Thoracic Spine.

In this post, we will explore:

• SIMPLE SIDE OF LUMBAR SPINE ANATOMY
• CHAIN REACTION BIOMECHANICS OF THE LUMBAR SPINE

The posts that follow will focus on Probable Suspects for the Lumbar Pain as well as a Movement Focus on preventative measures for Lower Back Pain.

SIMPLE SIDE ANATOMY OF THE LUMBAR SPINE

As we look at the entire spine, we have to remember that it serves many purposes but the two main ones are:

1) Protects the Spinal cord/nerves

2) Transmitter of force and movements throughout the body.

Looking at the 5 Lumbar Vertebrae, we see that they are larger than the thoracic and cervical spine. In fact, they become larger and larger as we descend from L1 to L5. These vertebrae are kidney shaped and constructed to participate in the weight-bearing of the entire column.

Functionally, the posterior arches are developed with large SPINOUS PROCESSES that project directly posterior. The TRANSVERSE PROCESSES are large and those at L3 are the usually the most broad. Interestingly, the lumbar lordosis is an anterior convexity with L3 being the most anterior. L4 and L5 have limited motion because of the strong attachments of of the iliolumbar ligaments to the pelvis, so L3 becomes the segment that is freely movable. This is interesting as many of the disc herniation that I encounter happen between L4 and L5.

The articular pillar has a:

1. SUPERIOR zygapophysial joint that faces POSTERIOR AND MEDIAL and is CONCAVE.
2. INFERIOR zygapophysial joint that faces ANTERIOR AND LATERAL and is CONVEX.

In between the zygapophysial joints lies the Pars Interarticularis. Disruption or fracture of this area is called spondylolysis. When the pedicle and superior articular pillar slide anteriorly while the spinous process, laminae and inferior articular pillar are held posteriorly this is called a Spondylolisthesis. According to Gary Gray, PT even though the vertebrae ends up moving in the Sagital plane, it is actually caused in the TRANSVERE PLANE. Unfortunately, because of the orientation of the facets, there is limited Transverse plane motion.

CHAIN REACTION BIOMECHANICS OF THE LUMBAR SPINE

This is where the Lumbar spine really starts to get interesting. As it has been noted many times in this blog, a Principle of Function is that Function is 3-D. Relating this to the spine, we know that the the vertebrae will have motion (of some degree) in all three planes of motion. In Applied Functional Science, we call this TRI-PLANAR COUPLING OR TROUPLING. This means that if there is motion in one plane there will also be motion in the other planes of motion.

Because of the Troupling of the Lumbar Spine we see that we can have both:

• Type I motion: lateral flexion and rotation to opposite sides
• Type II motion: lateral flexion and rotation to the same side
• Type III motion: lateral flexion and rotation to the same or opposite side WITH Sagital Plane flexion or extension.

Because of the ability of the Lumbar Spine to have the Type I, II, III motion, it can be considered a "Main Street" of the body, meaning that motion from the ground up and top down are transmitted into the Lumbar Spine. If we are lacking motion somewhere in the body, the Lumbar Spine is a great friend and will take up that motion. Unfortunately, due to the repetitive nature of these movements, we see that the lower back is beaten up a lot.

In the upcoming posts, we will examine some Lower Back Pain causes as well as some preventative work that can be done.

As always, questions, comments and suggestions are welcome.

Happy Monday!

Will