Tag Archives: thoracolumbar fascia

Notes on Anatomy and Physiology: Slings at the Front, Slings at the Back

For awhile now, we’ve been delineating hand to foot continuities that run throughout the body, providing strength, flexibility and a more developed sense of one’s body in space as they unfold. These patterns of uninterrupted flow, created by sequences of muscle, tendon, fascia and bone, come and go with movement.

We saw, last time, how motion of the hands helps create lines of pull that travel by various routes up into the torso. Our task today is to look for some of the strings that will convey these impulses from the torso down into the pelvis, legs and feet.

Back of the torso

A good place to start is at the back of the trunk. Remember that you can enlarge an image simply by clicking on it.

The next two drawings provide an overview of what Myers calls the Back Functional Line. Both illustrations reveal the same continuous line of pull running across the back and linking up each hand with the opposite leg.

           

Fig 1 The Back Functional Line. Myers, page 170

Fig 2 Diane Lee refers to this same line as the posterior oblique sling. No matter the name, the linkages connect thorax, pelvis and leg. Lee, page 52

Setting off from the left side, we begin with the left latissimus dorsi at its origin on the left upper arm, follow down to where the tendons of the latissimus merge with the thoracolumbar fascia, cross the midline over to the right gluteus maximus on the other side, travel with the right vastus lateralis as it passes along the outside aspect of the thigh, and end up where the vastus lateralis inserts onto the right tibia just below the knee cap.

If we had started with the right latissimus, we would have ended up at the left tibia. These two potential lines of pull crisscross the back of the torso to form an X. I use the word “potential’ because we can choose to either engage these lines or leave them dormant.

Other links carry the line eventually to the foot but you get the idea: myofascia working together with bone to form a continuous chain.

Now, let’s examine Continue reading

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Notes on Anatomy and Physiology: Function of the Thoracolumbar Fascia, Part 2

In the last note, we learned that bending forward with the low back in Step Up and Punch or Push Needle to Sea Bottom reverses the normal lumbar lordosis, lengthens the thoracolumbar fascia, tautens its fibers and stores elastic energy. We saw that simply letting the weight settle in the don yu , tor yu and set causes the pelvis to descend and gently rotate backwards, serving as another mechanism for drawing out the fascia. And we discussed how the elastic recoil energy stored by this expansion of connective tissue can be used to return the body to an upright position.

But the muscles of the low back are equally capable of bringing the body up from a forward bend, albeit at a much greater energy cost to the body. So, why the redundancy? Why design two different systems for bringing the body to an upright posture?

To answer this, we need to briefly review the concept of viscoelasticity.

Collagen is the principle fiber making up all connective tissue. Its behaviour is fundamentally shaped by viscoelasticity – the tendency for loaded structures to deform over time. I say over time but, in fact, this happens remarkably quickly. Within 1/3 of a second of loading and then holding collagen at a fixed, lengthened position, it will begin to sag and lose its stored elastic energy. When this happens to the thoracolumbar fascia, Continue reading

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Notes on Anatomy and Physiology: Function of the Thoracolumbar Fascia, Part 1

Today we want to take another look at the purposes served by our thoracolumbar fascia during the activities of a normal day.

The first thing to point out is that western medicine has only discovered the functional significance of this fascial sheet over the last 40 years. And yet the ancient art we practice has made routine use of this aspect of our physiology for centuries. A reminder that what is seen as discovery is often actually rediscovery. And an indication of the sophisticated understanding of human physiology that guides us in the practice hall.

Many in our culture still do not appreciate the crucial role played by the thoracolumbar fascia and other connective tissues of the body. It is good to keep this in mind when discussing the benefits of the Taoist Tai Chi™ internal arts of health with western health practitioners.

We have already looked at the structure of the thoracolumbar fascia and how it links hands to feet, the back to the front, the outside to the inside. It is time now to examine how it adds both structure and power to the spine.

Let’s start with thoracolumbar fascia as structure, as scaffold of the spine.

In our world, things are either supported from above with  Continue reading

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Notes on Anatomy and Physiology: The Thoracolumbar Fascia

Thus far, we have devoted considerable time to a review of the form and physiology of the spine, a structure that plays a central role in the body and in the Taoist Tai Chi™ internal arts of health.

There is one last element of the spinal region we need to examine and that is the thoracolumbar fascia.

Earlier, we described the deep fascia of the body as a thin, tough membrane that envelops the body’s muscles and then penetrates down through the muscle onto the bones beneath. As it extends out from the torso to the limbs and inserts into the base of the skull, the deep fascia forms part of a larger network of connective tissue whose function is to support, connect and separate all parts of the organism. Before proceeding further with this article, it might be useful to have another look at Notes on Anatomy and Physiology: Anatomy of the Fascial System that was posted several months ago.

Now, the thoracolumbar fascia is a large, diamond-shaped sheet that forms part of the deep fascia. Most developed in the lumbar region, it consists of multiple layers of crosshatched collagen fibers that cover the back muscles in the lower thoracic and lumbar area before slipping through these muscles to attach to the sacral bone.

As you review the images below, remember that you can enlarge any picture by simply clicking on it.

Fig 1 A surface view of the diamond-shaped thoracolumbar fascia which, by means of its extensions, connects with the upper and lower limbs, abdomen and pelvis. The muscles deep to the thoracolumbar fascia are depicted in red. The deltoid, trapezius and latissimus dorsi on the right side have been removed. Biel, page 194

As seen in the figures below, the thoracolumbar fascia has 3 layers – posterior, middle and anterior.  These insert on the transverse and spinous processes of the lumbar vertebrae. They also attach themselves to the iliac crest near the dimples of the low back and fuse with the posterior surface of the sacrum.

Fig 2 A view from above of a horizontal cross-section through the front wall of the abdomen. The top of the picture is the front of the body. The transversus abdominis and internal oblique muscles act as extensions of the thoracolumbar fascia as they sweep forward, thus connecting the back with the front. Neumann, page 390

Fig 3 A view from above of a horizontal cross-section through the torso at the level of L3. The bottom of the picture is the back of the body. The posterior, middle and anterior layers of the thoracolumbar fascia surround various muscles. Neumann, page 362

Because of its rich connections, the thoracolumbar fascia links up with most of the rest of the body:

  • the upper limbs, head and neck by virtue of it ties with the trapezius and latissimus dorsi. See figure 1 and 5.
  • the midline of the abdomen. The posterior and middle layers of the thoracolumbar fascia fuse laterally to form the lateral raphe, a weave of connective tissue that then joins with 2 abdominal  muscles, the transversus abdominis and internal oblique. These muscles wrap around to the front, surround the rectus abdominis and merge at the linea alba. See figures 2 and 3.
  • the deep structures of the spine by extending down to the spinal muscles, spinal ligaments, vertebral column and spinal canal. See figures 3 and 4.
  • the lower limbs by melding with the gluteus maximus. See figures 1 and 5.

Figure 4 Horizontal view of the lumbar region. The top of the image is at the back of the body. We see the continuous nature of the thoracolumbar fascia-supraspinous ligament-ligamentum flavum connection. The multifidus is one of the muscles running along the spine. Lee, page 29

Fig 5 The sweep of the thoracolumbar fascia as it connects disparate regions of the body with one other. Myers, pg. 171

Its centrality and its way of rippling out in all directions, allows the thoracolumbar fascia to serve as a nodal point. It draws together all corners of the body – the head and neck, hands, abdomen, pelvis and feet. With the spine lying in the midst of it all.

Using the analogy of a circus tent, the spine is the centre pole, the soft tissues of the body (including the thoracolumbar fascia) are the fabric of the tent wall, the arms and legs serve as guy wires, and the hands and feet are tent pegs.

Many of the lessons learned in our practice of the Taoist Tai Chi™ internal arts of health have to do with rhythmically drawing taut/separating out/lengthening, and then releasing, the entire fabric of the thoracolumbar fascia and its connections.

Next time, we will examine further the roles played by the thoracolumbar fascia in everyday life, something that has become much better understood over the last few decades.

1. Trail Guide to the Body, Third Edition, 2005, Andrew Biel, Books of Discovery, ISBN 0-9658534-5-4

2. Kinesiology of the Musculoskeletal System, 2010, Donald A. Neumann, Mosby Elsevier, ISBN 978-0-323-03989-5

3. The Pelvic Girdle, Second Edition, 1999, Diane Lee, Churchill Livingston, ISBN 0 443 05814 8

4. Anatomy Trains, Second Edition, 2009, Thomas W. Myers, Churchill Livingston Elsevier, ISBN: 978-0-443-10283-7

Bruce McFarlane MD

© Taoist Tai Chi Society of Canada 2010

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Notes on Anatomy and Physiology: Anatomy of the Fascial System

Recent work1, 2 on connective tissue has helped us better understand how all the seemingly disparate parts of our physiology are assembled into a coherent whole. For it is the connective tissue that literally knits us together, forming a web that binds, supports, connects and separates all regions of the body. From top to bottom. From structures at the surface to those lying deep in the interior.

Later, we will see how each individual cell is also implicated in this web and how the cell’s internal structure, its cytoskeleton, interacts with and is powerfully influenced by the larger web. But, for now, let’s look at the fascia, one specific form of connective tissue. By appreciating the impact of our art on fascia, we will begin to see how regular practice influences every element of the entire body.

The fasciae come in sheets and present as four distinct fascial layers. Intimately related to one another, they are constructed much like Russian dolls, each tube nestled inside another. Tubes within tubes. Each tube is continuous, ties into the structures that lie within the space it creates, and connects with the other layers.

Fig 1 Tubular structure of the fascial layers. Grant's Anatomy

Grant’s depiction of the fascial layers in figure 1 is not entirely accurate but it does give us a sense of their tubular nature. You can see how they each encompass a space within their borders and how they lie longitudinally, one inside the other.

The superficial fascia is the outermost layer. It covers the body’s entire surface, including the head. Loosely constructed and rich in adipose tissue, it warms and insulates. Because of its elasticity, it bends and moves as we do. It is the endpoint for the nerves and vessels that originate from Continue reading

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